date fruit (chemical composition,nutritional, and medicinal values, products

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ReviewReceived: 22 December 2012 Revised: 5 March 2013 Accepted article published: 28 March 2013 Published online in Wiley Online Library: 3 May 2013

(wileyonlinelibrary.com) DOI 10.1002/jsfa.6154

Date fruit: chemical composition, nutritionalandmedicinal values, productsZhen-Xing Tang,a,b Lu-E Shic and SalahM Aleidb

Abstract

Date fruit has served as a staple food in the Arab world for centuries. Worldwide production of date fruit has increasedalmost threefold over the last 40 years, reaching 7.68 million tons in 2010. Date fruit can provide many essential nutrients andpotential health benefits to the consumer. Date fruit goes through four ripening stages named kimri, khalal, rutab and tamer.The main chemical components of date fruit include carbohydrates, dietary fibre, enzymes, protein, fat, minerals, vitamins,phenolic acids and carotenoids. The chemical composition of date fruit varies according to ripening stage, cultivar, growingenvironment, postharvest conditions, etc. The nutritional and medicinal activities of date fruit are related to its chemicalcomposition. Many studies have shown that date fruit has antioxidant, antimutagenic, anti-inflammatory, gastroprotective,hepatoprotective, nephroprotective, anticancer and immunostimulant activities. Various date fruit-based products such asdate syrup, datepaste, date juice and their derivedproducts are available.Dateby-products canbeusedas rawmaterials for theproductionof value-addedproducts suchasorganic acids, exopolysaccharides, antibiotics, date-flavouredprobiotic-fermenteddairy produce, bakery yeasts, etc. In this paper the chemical composition and nutritional and medicinal values of date fruit aswell as date fruit-based products are reviewed.c 2013 Society of Chemical Industry

Keywords: date; nutritional values; medicinal activities

INTRODUCTIONDate palm (Fig. 1) is a particularly important crop in arid andsemi-arid regions of the world.1 It may be one of the oldestcultivated plants, with a history of more than 6000 years.1 Theearliest planting of date palm extended from northeast Africa tonorthwest of the Tigris and Euphrates plateau. The Phoenicianspromoted the planting of date palm around the Mediterranean,possibly because date fruit provided rapid energy to the consumerand could also be preserved for a long time. It was a perfect food forpeople such as soldiers during military expeditions and merchantsand explorers during long journeys, who may have scatteredand spread the plant by throwing away date seeds after eatingthe fruit.1 Today, more than 2000 varieties of dates are grownthroughout the world.2 They are mainly cultivated in the MiddleEast, North Africa, parts of Central and South America, southern

Europe, India and Pakistan.24 Based on FAO statistics, Egypt,Saudi Arabia, Iran, United Arab Emirates and Algeria are the mainproducing countries.5 Worldwide production of date fruit reached7.68 million tons in 2010, and expectations are that it will continueto increase.6,7 However, the average per capita consumption ofdate fruit has decreased recently owing to changing dietary habits

and lifestyles.810

The major component of date fruit (Fig. 2) is carbohydrate (themain sugars being sucrose, glucose and fructose), which may reachmore than 70%. Date fruit is also a good source of fibre and containsmany important vitamins and minerals such as calcium, iron,fluorine, selenium, etc.2,11,12 Based on its chemical composition,date fruit can be considered as one of the most appropriatesubstrates for manufacturing value-added products such asorganic acids, exopolysaccharides, antibiotics, date-flavouredprobiotic-fermented dairy produce, bakery yeasts, etc.13 Recent

studies have shown that date fruit and its aqueous extract havefree radical-scavenging, antimutagenic and immunomodulatoryactivities.8,14,15 Considering the importance of date fruit to thedate-producing regions, the chemical composition and nutritionaland medicinal values of date fruit as well as date fruit-basedproducts are discussed in this review.

CHEMICAL COMPOSITION OF DATE FRUITThe maturation stages of date fruit are usually described bythe Arabic terms kimri, khalal, rutab and tamer (Fig. 3). Manyphysical characteristics of date fruit at different stages have beenreported.2,8 Fruit at the kimri stage is the youngest, with a greencolour and hard texture. Fruit at the khalal stage may turn yellow,purplish-pink, red or yellowish-scarlet in colour depending on thecultivar; it still has a firm texture and maximum size and weight.Fruit at the rutab stage is less astringent, with a soft texture anddarker colour. At the tamer stage, whole fruit becomes dark brownin colour, with a soft texture and wrinkled appearance; it also has

Correspondence to: Zhen-Xing Tang, Department of Food Science, AnqingVocational and Technical College, 246003, Anqing, Anhui, China and DatePalmResearchCenter, KingFaisalUniversity, POBox420, Al-hasa, 31982, SaudiArabia. E-mail: [email protected]

a DepartmentofFoodScience,AnqingVocationalandTechnicalCollege,246003,Anqing, Anhui, China

b Date Palm Research Center, King Faisal University, PO Box 420, Al-hasa, 31982,Saudi Arabia

c College of Life and Environmental Sciences, Hangzhou Normal University,310016, Hangzhou, Zhejiang, China

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www.soci.org Z-X Tang, L-E Shi, SM Aleid

Figure 1. Photograph of date palm (published with permission of DatePalm Research Center, King Faisal University, Saudi Arabia).

Figure 2. Photographs of date fruit (published with permission of DatePalm Research Center, King Faisal University, Saudi Arabia).

A B

C D

Figure 3. Different stages of date ripening (published with permission ofDate Palm Research Center, King Faisal University, Saudi Arabia).

maximum soluble solid content, highest sweetness and lowestastringency. The chemical components of date fruit are describedin more detail in the following sections.

CarbohydrateOwing to its high carbohydrate content, date fruit can providerapid energy to the consumer.16 The most important carbohydratecomponents in date fruit are glucose, fructose and sucrose,

which can reach up to 7080% (Table 1).1,1719 Variation in

Table 1. Chemical composition of date fruit6,19

Component Concentration

Carbohydrate (g kg1) 526886Fructose 136368

Glucose 176414

Sucrose 0.533.9

Total fibre (g kg1) 35.7109Fat (g kg1) 114Ash (g kg1) 1019Protein (g kg1) 1126Minerals (101 g kg1) 41.74198.2Vitamins (103 g kg1) 22.55200.24

the carbohydrate concentration of date fruit can be attributed todifferences in cultivar, harvest/postharvest factors and growing

environment (temperature, humidity, fertiliser use, etc.).2023

Borchani et al.21 analysed the main chemical components ofdate fruits from 11 Tunisian cultivars and found that they were richin sugar (799.3880.2 g kg1 dry matter). Ali et al.23 found thatthe total sugar concentration in three Omani date cultivars rangedfrom 685.3 to 753.7 g kg1, the highest level being observedin Khalas cultivar. Amoros et al.24 found that the total sugarconcentration in Caqui 24 and Caqui 22 date fruits ranged from424 to 542 g kg1.

The total sugar concentration and the proportion of glucose andfructose in date fruit also change with growth stage (Table 2).25

The total sugar concentration usually increases from the kimristage to the tamer stage. Ahmed et al.26 reported that the totalsugar concentration at the kimri stage varied from 3.4 to 7.7%,while that at the tamer stage varied from 44.3 to 64.1%. In anotherdate cultivar the total sugar concentration in the tamer stage wasas high as 88%.2 The increase in sugar concentration from the kimristage to the tamer stage is related to loss of moisture from datefruit.2 The proportion of glucose and fructose in Barhi dates wasfound to increase from the kimri stage (4.9 and 2.8% respectively)to the tamer stage (29.7 and 27.6% respectively).

The date cultivar can also significantly affect the proportionof glucose and fructose in date fruit.8,23,25 Ali et al.23 observedan overall glucose/fructose ratio of 1.3 in three different Omanidate cultivars. However, Ismail et al.9 reported a higher fructoseconcentration (glucose/fructose ratio

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Date fruit www.soci.org

Table 3. Total dietary fibre concentration in different varieties ofdates21

Cultivar Total dietary fibre (%)

Alligh 11.45

Tranja 11.26

Deglet Nour 8.09

Bajo 16.95

Boufeggous 10.05

Goundi 10.16

Ikhouat 17.82

Kenta 12.18

Kentichi 20.25

Lgou 18.53

Touzerzaillet 17.25

FibreDate fruit can be considered as a good source of dietary fibresuch as cellulose, hemicellulose, lignin, pectin, etc.16,27 Like thecarbohydrate concentration in date fruit, the fibre concentrationis also dependent on date cultivar and ripening stage (Table 3).20

Elleuch et al.28 reported the dietary fibre concentration of twoTunisian date cultivars (Deglet-Nour and Allig) and studiedits characteristics. The dietary fibre concentration obtained forDeglet-Nour and Allig was 14.4 and 18.4% respectively. The dietaryfibre showed a high water-holding capacity (15.5%) and a highoil-holding capacity (9.7%). Borchani et al.21 found that the fibreconcentration in 11 Tunisian cultivars ranged from 80.9 to 202.5g kg1 dry matter. The date fibre presented a high water-holdingcapacity (6.2 103 g kg1) and a high oil-holding capacity (1.8 103 g kg1). Mrabet et al.29 determined the composition andwater- and oil-holding capacities of date dietary fibre from Tunisianoases. The total fibre concentration decreases when date fruitbecomes soft at the tamer stage.30 During the ripening process,enzymes gradually break down polysaccharides into more solublecompounds, thus decreasing the fibre concentration and makingthe fruit more tender and softer.16,29 The crude fibre concentrationin date fruit at the kimri stage is higher (6.213.2%) than that at thetamer stage (2.13.0%).1 Al-Turki etal.31 found that the proportionof pectin in date fruit decreased from the kimri stage (44.4 g kg1)to the tamer stage (16.8 g kg1).

MineralsMany minerals such as boron, calcium, cobalt, copper, fluorine,iron, magnesium, manganese, potassium, phosphorus, sodium,zinc, etc. are found in date fruit.11,12,20,21 Of all the minerals presentin date fruit, the potassium concentration is probably the highest,reaching up to 0.9%.

The mineral concentration in date fruit is influenced by soilfertility, date cultivar and ripening stage (Table 4).32 Amira et al.25

found that the mineral concentration in five Tunisian date cultivarsincreased with ripening. The mineral concentration in DegletNour variety at the kimri stage was increased from 1.06% atthe rutab stage and 3.25% at the tamer stage. However, otherresearchers found that the mineral concentration decreased withdate ripening.30,3335 Al-Shahib and Marshall2 reported that themineral concentration in date fruit decreased from 3.7% at the kimristage to 2.8% at the khalal stage, 2.6% at the rutab stage and 1.7%at the tamer stage. The concentrations of phosphorus, potassium,calcium, magnesium, sodium and zinc decreased from the kimri

stage to the tamer stage. Al-Hooti et al.36 found that the mineralconcentration in five date varieties was dependent on the ripeningstage. The concentration of iron in four cultivars decreased fromthe kimri stage to the tamer stage, whereas it increased in Luludate. The concentrations of calcium, magnesium, phosphorus,potassium, sodium and zinc in all five cultivars decreased fromthe kimri stage to the tamer stage. Rastegar et al.37 also foundthe mineral concentration decreased from the kimri stage to thetamer stage. Among the studied minerals, potassium was mostabundant at 11.727.2 g kg1.

EnzymesEnzymes in date fruit, namely invertase, -galactosidase,endo-1,4--D-glucanase, pectin methyl esterase, cellulase andpolyphenol oxidase, play an important role in fruit softening

and maturation.3840 The activities of these enzymes changewith ripening stage.37,41 Invertase is responsible for hydrolysingsucrose to glucose and fructose. The activity of invertase increasessharply from the kimri stage, reaching its maximum at the tamerstage.37 Pectin methyl esterase can convert protopectin to solublepectin. The activity of pectin methyl esterase increases from thekhalal stage to the rutab stage and then decreases sharply atthe tamer stage.2,27,37 The role of cellulase in date fruit softeningis uncertain. Awad et al.38 showed that the activity of cellulasewas relatively low at the kimri stage, then increased sharply toits maximum at the khalal stage, followed by a slight decreaseat the rutab stage. Similar results were reported by Rastegaret al.37 -Galactosidase activity is very low at the green stage, thenincreases gradually to its maximum at the tamer stage.37,40 Datefruit softening during ripening may be due, at least partially, to theaction of -galactosidase.42 Loss of galactosyl residues from pectinfractions during ripening, probably caused by -galactosidase, hasbeen reported.41,43 The involvement of endo-1,4--D-glucanase inthe softening process of date fruit was reported by Rastegar etal.37

The activity of endo-1,4--D-glucanase increased significantly withfruit growth and reached its maximum at the rutab stage (withthe exception of Shahani cultivar), followed by a slight decreaseat the tamer stage. Polyphenol oxidase is mainly involved inthe metabolism of tannins. The activity of polyphenol oxidasedecreases from the kimri stage to the tamer stage.30,34 Therelation between polyphenol oxidase activity and the intensityof date colour during ripening has been studied.44 Through themetabolism of tannins, the colour of date fruit changes from yellowto brown.

CarotenoidsMajor carotenoids in date fruit include lutein, -carotene,zeaxanthin and neoxanthin.45 The carotenoid concentration indate fruit may be dependent on many factors such as date cultivar,maturation stage and drying and postharvest conditions.11,45

Carotenoid degradation occurs during ripening from the khalalstage to the tamer stage, so ripe date fruit has a low carotenoidconcentration. Al-Farsi et al.11,14 reported that around 430% ofcarotenoids in date fruit were degraded after sun drying. Accordingto the USDA National Nutrient Database for Standard Reference,Release 19 (2007), the total carotenoid concentration in DegletNoor and Medjool dates is 0.81 and 1.12103 g kg1 respectively.The -carotene concentration in Algerian date varieties DegletNoor, Tantebouchte and Hamraya was found to be 6.44, 3.3 and2.5 105 g kg1 respectively, while the lutein concentration was1.56, 0.28 and 0.336 103 g kg1 respectively.6,45

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Table 4. Mineral concentration in different varieties of dates at different ripening stages37

Mineral concentration (102 g kg1)

Macroelements Microelements

Cultivar Ripening stage K Ca Mg Na Mn Zn Fe

Shahani Kimri 2720 440 330 120 3.6 3.5 3.5

Khalal 2330 300 240 132 1.3 2.3 2.0

Rutab 1350 150 130 123 0.7 1.4 1.8

Tamer 1170 140 114 129 0.4 1.4 1.6

Piarom Kimri 2440 360 275 124 1.3 2.5 2.4

Khalal 1940 230 156 129 1.1 1.7 1.5

Rutab 2040 238 225 128 0.6 2.8 2.3

Tamer 1380 160 123 126 0.4 2.0 1.7

Deiry Kimri 2630 490 340 133 1.3 2.1 2.5

Khalal 2300 450 370 128 1.1 1.9 2.0

Rutab 1440 200 173 123 0.6 1.5 1.2

Tamer 2440 385 250 134 1.6 2.3 1.8

Phenolic acidsPhenolic acids are a class of bioactive substances containing ahydroxylated benzene ring with one or more carboxyl groups.Many studies have showed that date fruit is rich in phenolicacids.11,46 Differences in date fruit phenolic acid concentrationare attributed to date cultivar, environmental conditions, etc.Mansouri et al.47 found that the main phenolic acids in sevenAlgerian varieties of date fruit were p-coumaric acid, ferulic acid,sinapic acid, some cinnamic acid derivatives and three differentisomers of 5-O-caffeoyl shikimic acid. The main phenolic acids inOmani date fruit were ferulic acid, caffeic acid, p-coumaric acidand o-coumaric acid.6,14 The total concentration of these phenolicacids varied from 0.0261 to 0.1227 g kg1 and from 0.0606 to0.1477 g kg1 in fresh and dried dates respectively. Chaira et al.48

found the lowest phenolic acid concentration in Mermella cultivar(0.0573 g kg1) and the highest in Korkobbi cultivar (0.5466 gkg1). The main phenolic acids were ellagic acid, gallic acid andp-coumaric acid. Caffeic acid was not detected.

FlavonoidsFlavonoids are important phenolic compounds that include proan-thocyanidins, flavanoid glycosides and anthocyanins.11,47,49,50

Hong et al.49 identified 13 flavonoid glycosides of luteolin,quercetin and apigenin in date fruit at the khalal stage. Chairaet al.48 found the highest concentration of flavonoids in Tunisiandates in Korkobbi cultivar (544.6 g kg1). Biglari et al.51 reportedthat the flavonoid concentration in Iranian date fruit varied from0.0162 to 0.8179 g kg1.

Other chemical componentsProteinMost proteins with molecular weight between 12 and 72 kDa indate fruit are soluble albumins. The protein concentration in datefruit is around (1.53.2) 103 g kg1, varying with date cultivarand ripening stage.9,11 The protein concentration in date fruitat the kimri stage is 5.56.4%. After the kimri stage the proteinconcentration begins to decrease gradually, reaching 2.02.5% atthe tamer stage.16,20,33,52 The decrease in protein concentrationduring ripening is attributed to non-enzymatic browning (Maillard)reactions and tannin precipitation. Twenty-three amino acids have

been found in date fruit, most of which are not found in otherpopular fruits such as oranges, apples and bananas.2 The aminoacid composition of date fruit varies with maturation stage. Highconcentrations of glutamic acid, aspartic acid, lysine, leucine,alanine and serine are found at the kimri stage, while glutamicacid, aspartic acid, lysine, leucine, proline and glycine are mostabundant during the ripening stages.53

Fat and fatty acidsThe fat concentration in date fruit is very low, usually in the range0.10.9%.22,25,30,52 The fat of date fruit is concentrated in the skin.The role of fat in date fruit is to protect the fruit. Major fatty acids indate fruit include lauric acid, myristic acid, palmitic acid and oleicacid.2,27,54 Hasnaoui et al.20 reported fat concentrations between 1and 4.76 g kg1. Analysis of variance of fat concentration showeda significant difference between cultivars.

VitaminsDate fruit has reasonable amounts of vitamins, including vitaminA, vitamins B1 and B2, niacin (nicotinic acid), vitamin C and folicacid.2,6,18,27 The vitamin concentration in date fruit decreases withmaturation owing to drying and environmental factors.2,8,34,55

PhytosterolsDate fruit contains many phytosterols.56,57 However, the changein phytosterol concentration in date fruit during ripeningis still unclear. In a recent study, Liolios et al.58 identifiedvarious phytosterols in date fruit, including campesterol,stigmasta-5,22-dien-3-ol, -sitosterol, sitosterol, lupenone,lupeol, 24-methylenecycloartanol, (E)-24-propylidenecholesterol,stigmastan-3,5-diene, cholest-4-en-3-one, 4-methyl-cholest-4-en-3-one, spinasterone, stigmast-4-en-3-one and cholesta-3,5-diene.

PhytoestrogensPhytoestrogens in date fruit were revealed by Thompson et al.59

The chemical structure of phytoestrogens is similar to thatof estradiol. There are three major classes of phytoestrogens,namely isoflavones, coumestans and lignans. The distributionof phytoestrogens in different date cultivars and the change inphytoestrogen concentration during ripening have not yet beeninvestigated.

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Table 5. Nutritional and medicinal values of date fruit

Nutritional or medicinal value Observed effect(s) and reference(s)

Antioxidant activity Inhibits peroxidation and protein oxidation and neutralises superoxide and hydroxyl radicals6365,132

Antimutagenic activity Inhibits benzo(a)pyrene-induced mutagenecity in the Ames test75

Gastrointestinal-protective activity Increases gastrointestinal transit time and reduces ethanol-induced gastric ulceration84,85

Hepatoprotective activity Reduces CCl4-induced elevation of plasma enzyme and bilirubin concentrations90

Anti-inflammatory activity Reduces erythrocyte sedimentation rate (ESR) and plasma fibrinogen and increases body weight gain andfood efficiency ratio80

Nephroprotective activity Inhibits hepatic lipid peroxidation and ameliorates superoxide dismutase (SOD), glutathione peroxidase(GPx) and catalase (CAT) activities63

Anticancer activity Significantly stimulates IFN- mRNA expression in cells and increases Th1 immune response65

Gonadotropic activity Increases sperm count in guinea pigs, enhances spermatogenesis and increases testosterone andfollicle-stimulating hormone concentrations98

NUTRITIONAL ANDMEDICINAL VALUES OFDATE FRUITAntioxidant activityAntioxidant activity of date fruit has been reported by manyinvestigators (Table 5).14,24,31,47,60,61 Date fruit extract can inhibitprotein oxidation as well as neutralise superoxide and hydroxylradicals. Many medicinal values such as hepatoprotective,nephrotoprotective and neuroprotective effects are related to

the antioxidant activity of date fruit.10,6265 Chaira et al.66 foundthat Korkobbi cultivar had the best lipoperoxyl radical-scavengingactivity, while Rotbi cultivar had good ability to scavenge hydroxylradicals. The antioxidant activity of date fruit is attributed tophytochemical compounds such as phenolic acids, flavonoids,anthocyanins, etc. as well as the mineral selenium.14,61,67 Seleniumcan contribute to the antioxidant effect through its important rolein activating enzymes related to reactive oxygen species (ROS)detoxification.68,69

Three methods are currently used to evaluate the antioxidantcapacity of date fruit in vitro, namely 2,2-diphenyl-1-picrylhydrazyl(DPPH) radical-scavenging ability, ferric-reducing ability of plasma

(FRAP) and oxygen radical absorbance capacity (ORAC).7072

Chaira et al.73 demonstrated that 100 g of ethyl acetate extract ofDeglet Noor cultivar could inhibit DPPH radical formation by 54%,while the same amount of extract from Alig cultivar did not havethe ability to scavenge DPPH radicals. Rock et al.72 showed thatMedjool and Hallawi date cultivars could inhibit DPPH radicals by44 and 39% respectively at a concentration of 10 g mL1. AbdulAmeer61 investigated the antioxidant capacity of 16 date cultivarscommonly grown in Bahrain using the FRAP assay. Fruit at theunripened stage had the highest antioxidant activity (57.1 4.31mmol kg1), followed by fruit at the rutab (12 mmol kg1) andtamer (9.4 0.21 mmol kg1) stages. Al-Farsi et al.11 evaluatedthree Oman date cultivars using the ORAC method and found thatthe antioxidant ability of fresh dates was higher than that of drieddates. Investigation of the free radical-quenching activity of datefruit extract in a cell culture system has also been carried out.Asadi-Shekaari et al.74 showed that aqueous extract of date fruithad potent activity against H2O2-induced cell damage in HEPG-2,A172, U937 and PC12 cell lines.

Antimutagenic activityVayalil75 investigated the antimutagenic activity of date fruit usingthe Ames mutagenicity assay (Table 5). The results showed thatdate fruit could inhibit benzo(a)pyrene-induced mutagenicity

on Salmonella tester strains TA-98 and TA-100 with metabolicactivation. Components such as proanthocyanidins, anthocyanins,-carotene, phenolic acids and selenium present in date fruit have

been reported to have an antimutagenic effect.7679 However,more studies are needed to evaluate the antimutagenic effect ofthese compounds.

Anti-inflammatory activityIt is very important for human health to control the excessivegeneration of free radicals by inflamed leukocytes. Mohammedand Al-Okbi80 investigated the anti-inflammatory potential of datefruit. The results showed that oral administration of methanolicor aqueous extract of date fruit could suppress adjuvant-inducedinflammation in the foot, reduce erythrocyte sedimentation rate(ESR) and plasma fibrinogen and increase body weight gain andfood efficiency ratio compared with adjuvant-treated controls.Date fruit constituents such as proanthocyanidins, flavonoids,polyphenols, -carotene and selenium may contribute to the

anti-inflammatory effect.8183

Gastrointestinal-protective activityDate fruit is traditionally used to protect the gastric mucosafrom the damaging effects of stomach acids.84 Al-Qarawiet al.85 investigated the influence of date fruit extract ongastrointestinal mobility and found that it caused a concentration-dependent increase in transit time (Table 5). Aqueous andethanolic extracts of date fruit could be effective in amelioratingethanol-induced gastric ulceration. The gastroprotective activityof date fruit is correlated with antioxidant compounds suchas proanthocyanidins, flavonoids, -carotene, -sitosterol and

selenium.8689

Hepatoprotective activityLiver disease is one of the most serious health problems, andno satisfactory protective drugs are available. Saafi et al.63

reported that date fruit extract could decrease the levels ofhepatic marker enzymes (transaminases, alkaline phosphatase, -glutamyl transferase and lactate dehydrogenase) and hepaticlevels of malondialdehyde and concomitantly increase thelevels of antioxidant enzymes. Al-Qarawi et al.90 found thatfeeding rats with date fruit extract could significantly reducethe CCl4-induced elevation of plasma enzyme and bilirubinconcentrations. Histopathological studies also confirmed thebiochemical observations that date fruit extract possessed a


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hepatoprotective effect. Many studies have indicated that thehepatoprotective activity of date fruit may be due to compoundssuch as selenium, anthocyanins, ferulic acid, caffeic acid, quercetin,

-carotene, proanthocyanidins, luteolin, etc.89,9194

Nephroprotective activityNephrotoxicity is a common side effect of pharmacological agentssuch as analgesics, antibiotics, cytostatics and other drugs. Al-Qarawi et al.95 investigated the nephroprotective effect of datefruit extract on gentamicin-induced nephrotoxicity in rats. Theresults showed that feeding rats with date fruit extract couldreduce the levels of plasma creatinine and urea and ameliorategentamicin-induced damage to the proximal tubular region ofthe kidney. Saafi et al.63 found that date fruit extract couldcombat liver damage induced by dimethoate, as revealed byinhibition of hepatic lipid peroxidation, amelioration of superoxidedismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT)activities and improvement of histopathological changes. Someresearch has suggested that vitamin E, ascorbic acid, selenium,quercetin and melatonin in date fruit may be responsible for itsnephroprotective activity.96,97

Gonadotropic activityDate fruit has been used as an important ingredient in variousaphrodisiacs and tonics. El-Mougy et al.98 found that datefruit extract could increase the sperm count in guinea pigsas well as enhance spermatogenesis and increase the levelsof testosterone, follicle-stimulating hormone and luteinisinghormone in rats (Table 5). Phytochemicals such as genistein,vitamin A and selenium have been reported to protect testicularfunctions against various stresses and to possess gonadotropic

activity.99101

Prevention and control of cancerDate fruit has shown potential benefit against many types ofcancer, but only a few studies have been reported on theanticancer activity of date fruit. Vayalil75 found that date fruitwas effective against chemical carcinogens by demonstratingits antimutagenic activity on Salmonella tester strains. Excessiveproduction of reactive oxygen radicals and other reactive radicalspecies is related to the formation of cancer. Thus an antioxidantwith the ability to scavenging such radicals can be considered asa potential anticancer agent.75 Since date fruit can scavenge freeradicals, it can be considered as a potential anticancer agent. Manyphytochemicals in date fruit, including phytoestrogens such asgenistein, glycitein and daidzein, phenolic acids such as gallic acidand ferulic acid, anthocyanins, flavonoids, phytosterols, vitaminsand minerals such as magnesium, manganese, zinc, copper andselenium, have shown anticancer activity.

Activation of the immune system is another approach tocancer prevention. Puri et al.102 showed that date fruit extractcould improve immune activity in rats. Seven days of continuoustreatment with date fruit extract could stimulate the antibody titreand plaque-forming cells. In a recent study, Karasawa et al.65 alsofound that date fruit extract could significantly stimulate IFN-mRNA expression in cells and increase Th1 immune response.These effects were attributed to polyphenols and polysaccharidespresent in date fruit.67

Some studies showed that dietary fibre could be considered asan antimutagen in the intestinal tract because it could dilute

mutagen concentrations and increase faecal transit time byincreasing faecal mass through its water-binding capacity. Al-Qarawi et al.84 showed that date fruit extract could be effective indecreasing ethanol-induced gastric ulceration owing to the dietaryfibre contained in date fruit. Recently, Ishurd and Kennedy103

extracted the glucans from date fruit and validated their dose-dependent anticancer activity.

Prevention and control of diabetes mellitusDate fruit has potential medicinal value for the prevention andcontrol of diabetes mellitus owing to its richness in antioxidantsand minerals. Phenolic compounds in date fruit can inhibit theactivities of -glucosidase and -amylase.71 The digestion rate ofcarbohydrate is reduced when the activities of these enzymes areinhibited; as a result, less glucose is absorbed into the circulation.

Many studies have indicated that there is a deficiency of certainminerals in diabetic patients. Therefore the use of minerals canbe investigated as a potential preventive and treatment strategyfor diabetes. As mentioned above, date fruit is rich in mineralsinvolved in glucose metabolism, so it may be potentially beneficialfor the prevention of diabetes. Such minerals include magnesium,zinc, chromium and selenium.104 Therefore regular consumptionof date fruit may prevent the development of diabetes in healthypeople as well as control diabetes in patients who are deficient inthese minerals.

Generally, diabetes is accompanied by increased oxidative stressdue to hyperglycaemia, which leads to micro- and macrovascularcomplications. Several studies have shown significantly decreasedlevels of - and -tocopherol, lycopene, - and -carotene, lutein,-cryptoxanthin, retinol, zeaxanthin and ascorbic acid in diabeticpatients.105 Therefore the use of antioxidants is considered as atreatment strategy for diabetes either alone or in combinationwith other treatment strategies.106 As mentioned above, date fruithas strong antioxidant activity owing to its content of phenoliccompounds and carotenoids. These compounds can effectivelyreduce ROS production by inhibiting several ROS-producingenzymes, chelating trace metals and inhibiting phospholipasesA2 and C.107

Evidence has shown that dietary phytoestrogens may play abeneficial role in diabetes. Phytoestrogens such as isoflavones,lignans, genistein and daidzein appear to act through variousmechanisms that modulate pancreatic insulin secretion or regulateglucose homeostasis.108,109 Thus the high levels of phytoestrogensin date fruit may potentially help to maintain normal glucosemetabolism in healthy people as well as in diabetic patients.

Weickert and Pfeiffer110 showed that consumption of date fruitrich in dietary fibre could improve insulin sensitivity, modulate thesecretion of certain gut hormones and affect various metabolicand inflammatory markers that are associated with metabolicsyndrome. Therefore the dietary fibre in date fruit may help toprevent the development of diabetes.

Therapy for cardio- and cerebrovascular diseases (CCVD)Date fruit can provide a therapy against the initiation andprogression of CCVD in many ways, e.g. by reducing hypertension,hypercholesterolaemia and lipoprotein oxidation, enhancingserum antioxidant status and alleviating harmful effects ofoxidative stress.

Hypertension is a major risk factor for the development of CCVD.Date fruit has been used for centuries as an antihypertensive foodand medicine in eastern Africa as well as in the Middle East.


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However, only recently has the antihypertensive activity of datefruit been studied.

Controlling the activity of angiotensin-converting enzyme (ACE)in the pulmonary circulation as well as in the endothelium ofblood vessels is an important treatment strategy to reduce bloodpressure. Braga et al.111 showed that date fruit had potent ACE-inhibitory activity. Also, the total phenolics in date fruit possessedACE-inhibitory activity.

The minerals in date fruit can play an important role inmaintaining the blood pressure. A high sodium intake coupled witha low potassium intake can cause a rise in blood pressure.112,113

The best way to maintain the blood pressure is to consumefruits and vegetables with low sodium content. Date fruit isan excellent dietary source of potassium with very low sodiumcontent. Consumption of date fruit may prevent the developmentand progression of hypertension by maintaining the electrolytebalance within the body. Other major elements that have beenshown to protect against hypertension are magnesium andcalcium.

Hypercholesterolaemia is another major risk factor for thedevelopment of CCVD. Alsaifetal.114 found that adding date fruit toa high-cholesterol diet fed to hamsters could significantly reducethe cholesterol-induced increase in organ weights and plasma totalcholesterol, triglyceride and LDL cholesterol levels and increase theplasma HDL cholesterol level. The study thus suggested that datefruit supplementation had good potential to modulate cholesterolabsorption or metabolism. The dietary fibre and phytochemicals indate fruit may be responsible for this effect. Date dietary fibre mayexert significant hypocholesterolaemic activity by three potentialmechanisms: (a) it may reduce the absorption of cholesterol andreabsorption of bile acids in the intestinal lumen; (b) it mayreduce insulin secretion; (c) its fermentation can produce short-chain fatty acids that may inhibit hepatic cholesterol biosynthesis.Phytochemicals such as phytosterols and phytoestrogens caninhibit intestinal cholesterol absorption by displacing cholesterolfrom micellar binding and thereby lower the cholesterol level.115

The pronounced cholesterol-lowering effects of stigmasterol andsitosterol have been demonstrated in animals116 and humans.117

FOOD PRODUCTS FROMDATE FRUITFresh date fruit can be eaten directly without any fumigationor washing. To meet the high quality standards expected byconsumers, date fruit is also processed into many types of product,and a number of date-packing and date-processing factories havebeen built.

Date juice-based productsIn the most common method for producing date juice, a mixtureof pitted (or sometimes unpitted) date fruit and water is heatedto boiling and then filtered and concentrated.118 Date juice has atendency to lose flavour, vitamins and colour during processingwhen subjected to open conditions.119 To overcome this problem,some mild technologies have been applied during the productionof date juice. The juice can be extracted at lower temperatureunder vacuum.118

Date juice (Fig. 4A) has considerable antioxidant andantimutagenic activity.75 Many products such as carbonated andnon-carbonated beverages, date juice wine, ice cream, jam andjelly (as a sugar substitute) are made using date juice.1

A B

C D

E F G

Figure 4. Date products: A, date juice; B, date syrup; C, date paste; D, datepickle; E, date bar; F, date butter; G, date jam (published with permissionof Date Palm Research Center, King Faisal University, Saudi Arabia).

Date syrup-based productsDate syrup (Fig. 4B) has the same quality as date juice but is moreconcentrated. Date syrup is one of the most common date fruitderivatives. Date fruit at the khalal stage of maturity, being highin soluble sugars, is an excellent raw material for the preparationof date syrup.120 Like the method for producing date juice, thegeneral process for the production of date syrup includes pitting,hot water extraction, autoclaving, filtration and concentration.Recently, Ei-Sharnouby et al.121 reported that the recovery ofsoluble solids obtained by pectinase and cellulase extractionwas almost twice that obtained by conventional hot water andautoclaving extraction. The date syrup extracted with pectinaseand cellulase was found to be a good substitute for sucrose inbakery products.

Date syrup can be used in beverages, confectionery, biscuits,bread, ice cream and cakes as a sweetening and flavouringagent.122 Liquid date sugar is made from refined date syrup, beinga mixture of various sugars (i.e. glucose, fructose and sucrose)with a soluble solid content of 75%, and is used mostly in softdrinks, cakes, jellies, preserved fruits, confectionary products andice cream.

Date paste-based productsDate food producers are very interested in producing date pastein order to reduce transportation and storage costs but also toconvert dates of inferior quality into a value-added product.30

For the preparation of date paste (Fig. 4C), pitted date fruit issoaked in hot water or steamed under a certain pressure andthen ground. To improve the shelf life and desirable colour ofdate paste, citric acid or ascorbic acid (0.2%) is generally used.118

Date paste can be used as a substitute for flour in bakery andconfectionary products.118,123 The use of 48% date paste inbread formulation results in a significant improvement in thedough rheological properties, delays gelatinisation, improves gasproduction and retention, extends the shelf life, retards staling


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and improves the crumb and crust characteristics. Sanchez-Zapataet al.124 investigated the effect of date paste on the quality of acooked meat product. The results showed that the addition ofdate paste to the meat product could decrease its fat content andincrease the nutritive value of the product.

Date paste can also be used to prepare date candy and datepowder.123 To further enhance the nutritive value of date paste,it can be mixed with skim milk powder, chocolate and fruit juice(e.g. banana, orange, pineapple, apple, grape or strawberry juice)to yield a high-protein product, tamar heep.

Products from by-products of date processingDate processing results in substantial losses of date palm fruit.Dates of imperfect appearance are discarded as unsuitable forpackaging for the marketplace. However, these by-products canbe used as substrates for fermented products because of theirnutritive components for micro-organism growth and metabolism,such as sugars, protein, minerals and fibre. Many studies on thepotential use of date by-products as substrates for fermentedproducts have been reported.

Acourene et al.125 investigated the potential of date wasteas a substrate for the production of citric acid using strains ofSaccharomyces cerevisiae ATCC 1102 and Aspergillus niger ATCC16404. The results showed that 0.1264 kg L1 citric acid couldbe obtained under optimal fermentation conditions. Chauhanet al.126 investigated the possibility of lactic acid production byLactobacillus sp. KCP01 using date juice as a carbon source. Theresults showed that 0.0151 kg L1 lactic acid could be obtainedunder optimal pH and temperature conditions.

Moosavi-Nasab and Yousefi127 utilised low-quality date syrupfor the production of bacterial cellulose using Gluconacetobacterxylinus. The results showed that 0.0435 kg L1 bacterial cellulosecould be obtained. Moosavi-Nasab et al.128 used Xanthomonascampestris with date syrup as a substrate to produce xanthan gum.The results showed that the maximum gum concentration couldbe increased to 8.9 103 kg L1.

Radwan et al.129 obtained a high yield of bleomycin (0.138 103 kg L1) when date syrup was used as an additional carbonsource.

Aleid13 incorporated probiotic micro-organismsBifidobacteriumlactis Bb-12, Bifidobacterium longum Bb-46 and Lactobacillusacidophilus La-5 into date paste. All three probiotic bacteria werecapable of surviving in date paste. The viable count of L.acidophilusremained above 6 103 log10 CFU kg1 in date paste until thethird week of storage.

Al-Jasass et al.130 investigated the production of the bakeryyeast strain S. cerevisiae using substrates of pure date syrup andpure molasses. The results showed that the overall biomass yieldfrom the pure date syrup substrate was significantly lower thanthat from the pure molasses substrate. This may be due to theeffect of yeast-toxic organic acids contained in date syrup at highconcentrations.

Other productsDate pickles (Fig. 4D), including pickles-in-oil, brine and salt-stockpickles and chutney, are other popular products that can be madeusing date fruit at the kimri and khalal stages.30 Pickles-in-oil areprepared using pitted fruit at the kimri stage with various spices,condiments and mustard oil.118 Chutney is composed of date fruit,vinegar, vegetables and hot spices.

Date bars (Fig. 4E) can be made using date pulp, sesame seeds,almonds and oak flakes and are very popular with young children.

Such fortified date fruit bars can also supply a reasonable amountof fat, protein, fibre and minerals.

Tamer stage dates with high sugar content are suitable formaking date butter (Fig. 4F).30 The procedure is similar to jammaking, except that the pH is adjusted to 4.7.118

Date pulp and clear date fruit extract can be used to preparedate jam (Fig. 4G) and date jelly respectively. Good date jam can bemade with a sugar concentration of 65%, a pectin concentrationof 1% and a pH of 33.2. Some date fruit cultivars such as Khalas,Sukkary and Ruzeiz are very suitable for jam making. Masmoudiet al.131 reported that various types of jelly prepared from datefruit had high adhesiveness, chewiness, cohesiveness and tasteattributes.

CONCLUSIONDate fruit plays an important role in date-growing regions, espe-cially in countries of the Middle East. Many chemical componentsof date fruit have been reported, the major one being carbohydrate(mainly sucrose, glucose and fructose). Date fruit is also a goodsource of fibre, vitamins, minerals, enzymes and phytochemicals,including carotenoids, phenolics and flavonoids. Date fruit can notonly provide antioxidant, antimutagenic and immunomodulatorybenefits to health but also has diverse medicinal values, includingantihyperlipidaemic, anticancer, gastroprotective, hepatoprotec-tive and nephroprotective activities. The observed medicinalproperties have a good relationship with the composition ofdate fruit, such as its high concentration of minerals and antioxi-dants. Date fruit has been processed into many products such asdate juice, date paste, date syrup and other derived products. Dateby-products can be used as raw materials for the production ofvalue-added products such as organic acids, exopolysaccharides,antibiotics, date-flavoured probiotic-fermented dairy produce,bakery yeasts, etc.

In the future we need to characterise and quantify the variousantioxidants present in date fruit and study their bioavailability andmetabolism in humans. In order to further explore the nutritionaland medicinal benefits of date fruit, we also need to exploreits health benefits and develop value-added food products andsupplements based on its functional components.

REFERENCES1 Ashraf Z and Hamidi-Esfahani Z, Date and date processing: a review.

Food Rev Int 27:101133 (2011).2 Al-Shahib W and Marshall RJ, The fruit of the date palm: its possible

use as the best food for the future? Int J Food Sci Nutr 54:247259(2003).

3 Tengberg M, Beginning and early history of date palm gardencultivation in the Middle East. J Arid Environ 86:139147 (2012).

4 Barrreveld WH, Date Palm Products. Food and AgricultureOrganization of the United Nations, Rome (1993).

5 FAO. [Online]. (2010). Available: http://www.FAO.org/ [23 January2013].

6 Al-Farsi MA and Lee CY, Nutritional and functional properties of dates:a review. Crit Rev Food Sci Nutr 48:877887 (2008).

7 El-May Y, Jeguirim M, Dorge S, Trouve G and Said R, Studyon the thermal behavior of different date palm residues:characterization and devolatilization kinetics under inert andoxidative atmospheres. Energy 44:702709 (2012).

8 Allaith AAA, Antioxidant activity of Bahraini date palm (Phoenixdactylifera L.) fruit of various cultivars. Int J Food Sci Technol43:10331040 (2008).

9 Ismail B, Haffar I, Baalbaki R, Mechref Y and Henry J, Physico-chemicalcharacteristics and total quality of five date varieties grown in theUnited Arab Emirates. Int J Food Sci Technol 41:919926 (2006).


2359


10 Al-Shoaibi Z, Al-Mamary MA, Al-Habori MA, Al-Zubairi AS andAbdelwahab SI, In vivo antioxidative and hepatoprotective effectsof palm date fruits (Phoenix dactylifera). Int J Pharmacol 8:185191(2012).

11 Al-Farsi M, Alasalvar C, Morris A, Baron M and Shahidi F, Comparisonof antioxidant activity, anthocyanins, carotenoids, and phenolicsof three native fresh and sun-dried date (Phoenix dactylifera L.)varieties grown in Oman. J Agric Food Chem 53:75927599 (2005).

12 Khan M, Sarwar A, Wahab M and Haleem R, Physico-chemicalcharacterization of date varieties using multivariate analysis. JSci Food Agric 88:10511059 (2008).

13 Aleid SM, Date Palm Biotechnology. Springer, New York, NY, pp.675706 (2011).

14 Al-Farsi M, Alasalvar C, Morris A, Baron M and Shahidi, F,Compositional and sensory characteristics of three native sun-dried date (Phoenix dactylifera L.) varieties grown in Oman. J AgricFood Chem 53:75867591 (2005).

15 Saffi EB, Arem AE, Issaoui M, Hammami M and Achour L, Phenoliccontent and antioxidant activity of four date palm (Phoenixdactylifera L.) fruit varieties grown in Tunisia. Int J Food Sci Technol44:23142319 (2009).

16 Habib HM and Irahim WH, Nutritional quality of 18 date fruit varieties.Int J Food Sci Nutr 62:544551 (2011).

17 Nehdi I, Omri S, Khalil MI and Al-Resayes SI, Characteristics andchemical composition of date palm (Phoenix canariensis) seedsand seed oil. Ind Crop Prod 32:360365 (2010).

18 Vayalil PK, Date fruits (Phoenix dactylifera Linn): an emergingmedicinal food. Crit Rev Food Sci Nutr 52:249271 (2012).

19 Baliga MS, Baliga BRV, Kandathil SM, Bhat HP and Vayalil PK, A reviewof the chemistry and pharmacology of the date fruits (Phoenixdactylifera L.). Food Res Int 44:18121822 (2011).

20 Hasnaoui A, Elhoumaizi MA, Hakkou A, Wathelet B and SindicM, Physico-chemical characterization, classification and qualityevaluation of date palm fruits of some Moroccan cultivars. J Sci Res3:139149 (2011).

21 Borchani C, Besbes S, Blecker C, Masmoudi M, Baati R and Attia H,Chemical properties of 11 date cultivars and their correspondingfiber extracts. Afr J Biotechnol 9:40964105 (2010).

22 Saffi EB, Trigui M, Thabet R, Hammami M and Achour L, Commondate palm in Tunisia: chemical composition of pulp and pits. Int JFood Sci Technol 43:20332037 (2008).

23 Ali A, Yusra M, Al-Kindi and Al-Said F, Chemical composition andglycemic index of 3 varieties of Omani dates. Int J Food Sci Nutr60:5162 (2009).

24 Amoros A, Pretel MT, Almansa MS, Botella MA, Zapata PJ and SerranoM, Antioxidant and nutritional properties of date fruit from Elchegrove as affected by maturation and phenotypic variability of datepalm. Food Sci Technol Int 15:6572 (2009).

25 Amira EA, Guido F, Behija SE, Manel I, Nesrine Z, Ali F, et al., Chemicaland aroma volatile compositions of date palm (Phoenix dactyliferaL.) fruits at three maturation stages. Food Chem 127:17441754(2011).

26 Ahmed IA, Ahemed AWK and Robinson RK, Chemical composition ofdate varieties as influenced by the stage of ripening. Food Chem54:305309 (1995).

27 Biglari F, Assessment of antioxidant potential of date (Phoenixdactylifera L.) fruits from Iran, effect of cold storage and addition tominced chicken meat. MSc Thesis, School of Industrial Technology,University Sains Malaysia, Penang (2009).

28 Elleuch M, Besbes S, Roiseux O, Blecker C, Derroanne C, Drira N, et al.,Date flesh: chemical composition and characteristics of the dietaryfibre. Food Chem 111:676682 (2008).

29 Mrabet A, Rodriguez-Arcos R, Gulen-Bejarano R, Chaira N, FerchichiA and Jimenez-Araujo A, Dietary fiber from Tunisian commondate cultivars (Phoenix dactylifera L.): chemical composition,functional properties, and antioxidant capacity. J Agric Food Chem60:36583664 (2012).

30 Hui YH, Fruit and Fruit Processing. Blackwell, Ames, IA, pp. 391411(2006).

31 Al-Turki S, Shahba MA and Stushnoff C, Diversity of antioxidantproperties and phenolic content of date palm (Phoenix dactyliferaL.) fruits as affected by cultivar and location. J Food Agric Environ8:253260 (2010).

32 Marzouk HA and Kassem HA, Improving fruit quality, nutritional valueand yield of Zaghloul dates by the application of organic and/ormineral fertilizers. Sci Hort 127:249254 (2011).

33 Shaheen MA and Al-Qurashi AD, Fruit chemical compositionand its correlation with some date palm cultivars during fruitdevelopment stages. J King Andulaziz Univ Meteorol Environ AridLand Agric Sci 18:1926 (2007).

34 Al-Qurashi AD, Physico-chemical changes during development andripening of Helali date palm fruit. J Food Agric Environ 8:404408(2010).

35 Mohammadzai I, Shah Z, Khan H, Ihsanullah and Khan H, Mineralcomposition of date palm fruit and pit by atomic absorptionspectrophotometry. J Chem Soc Pakistan 32:8790 (2010).

36 Al-Hooti S, Sidhu JS and Qabazard, H, Studies on the physico-chemicalcharacteristics of date fruits of five UAE cultivars at different stagesof maturity. Arab Gulf J Sci Res 13:553569 (1995).

37 Rastegar S, Rahemi M, Baghizadeh A and Gholami M, Enzyme activityand biochemical changes of three date palm cultivars with differentsoftening pattern during ripening. Food Chem 134:12791286(2012).

38 Awad MA, Adel D, Al-Qurashi S and Mohamed A, Biochemical changesin fruit of an early and a late date palm cultivar during developmentand ripening. Int J Fruit Sci 11:167183 (2011).

39 Zare Z, Sohrabpour M, Fazeli TZ and Kohan KG, Evaluation of invertase(B-fructo furanosidase) activity in irradiated Mazafaty dates duringstorage. Radiat Phys Chem 65:289291 (2002).

40 Mustafa AB, Harper DB and Johnston DE, Biochemical changes duringripening of some Sudanese date varieties. JSciFoodAgric37:4353(2006).

41 Cheng GY, Jiang Y, Chen S, Yang S, Liang H and Duan X,Combined effects of pectic enzymes on the degradation of pectinpolysaccharides of banana fruit. Pakistan J Bot 43:15011505(2011).

42 Farahnaky A and Afshari-Jouybari H, Physicochemical changes inMazafati date fruits incubated in hot acetic acid for acceleratedripening to prevent diseases and decay. Sci Hort 127:313317(2011).

43 Goulao LF, Santos J, Sousa I and Oliveira CM, Patterns of enzymaticactivity of cell wall-modifying enzymes during growth and ripeningof apples. Postharv Biol Technol 43:307318 (2007).

44 Al-Qarni SSM, Biochemical changes during date palm fruits ripening.MSc Thesis, Faculty of Science, King Saud University, Riyadh (2005).

45 Boudries H, Kefalas P and Hornero-Mendez D, Carotenoidcomposition of Algerian date varieties (Phoenix dactylifera) atdifferent edible maturation stages. Food Chem 101:13721377(2007).

46 Mattila P, Hellstrom J and Torronen R, Phenolic acids in berries, fruits,and beverages. J Agric Food Chem 54:71937199 (2006).

47 Mansouri A, Embarek G, Kokkalou E and Kefalas P, Phenolic profile andantioxidant activity of the Algerian ripe date palm fruit (Phoenixdactylifera). Food Chem 89:411420 (2005).

48 Chaira N, Mrabet A and Ferchichi A, Evaluation of antioxidant activity,phenolics, sugar and mineral contents in date palm fruits. J FoodBiochem 33:390403 (2009).

49 Hong YJ, Tomas-Barberan FA, Kader AA and Mitchell AE, The flavonoidglycosides and procyanidin composition of Deglet Noor dates(Phoenix dactylifera). J Agric Food Chem 54:24052411 (2006).

50 Gu LW, Kelm MA, Hammerstone JF, Beecher G, Holden J, HaytowitzD, et al., Screening of foods containing proanthocyanidins andtheir structural characterization using LC-MS/MS and thiolyticdegradation. J Agric Food Chem 51:75137521 (2003).

51 Biglari F, Alkarkhi AFM and Easa AM, Antioxidant activity and phenoliccontent of various date palm (Phoenix dactylifera) fruits from Iran.Food Chem 107:16361641 (2008).

52 Arem AE, Saffi EB, Flamini G, Issaoui M, Ferchichi A, Hammami M, etal.,Volatile and nonvolatile chemical composition of some date fruits(Phoenix dactylifera L.) harvested at different stages of maturity. IntJ Food Sci Technol 47:549555 (2012).

53 Ishurd O, Zahid M, Xiao P and Pan Y, Protein and amino acid contentsof Libyan dates at three stages of development. J Sci Food Agric84:481484 (2004).

54 Habib HM, Kamal H, Ibrahim WH and Al-Dhaheri AS, Carotenoids, fatsoluble vitamins and fatty acid profiles of 18 varieties of date seedoil. Ind Crop Prod 42:567572 (2013).

55 Mrabet A, Ferchichi A, Chaira N, Mohamed BS, Baaziz M and PennyTM, Physico-chemical characteristics and total quality of datepalm varieties grown in the Southern of Tunisia. Pakistan J Biol Sci11:10031008 (2008).


2360


56 Marangoni F and Poli A, Phytosterols and cardiovascular health.Pharmacol Res 61:193199 (2010).

57 Brufau G, Canela MA and Rafecas M, Phytosterols: physiologic andmetabolic aspects related to cholesterol-lowering properties. NutrRes 28:217225 (2008).

58 Liolios CC, Sotiroudis GT and Chinou I, Fatty acids, sterols, phenolsand antioxidant activity of Phoenix theophrasti fruits growing inCrete, Greece. Plant Foods HumNutr 64:5261 (2008).

59 Thompson LU, Boucher BA, Liu Z, Cotterchio M and Kreiger N,Phytoestrogen content of foods consumed in Canada, includingisoflavones, lignans, and coumestan. Nutr Cancer 54:184201(2006).

60 Allaith AAA, In-vitro evaluation of antioxidant activity of differentextracts of Phoenix dactylifera L. fruit as functional foods. DtschLebensm Rundsch 101:305308 (2005).

61 Abdul Ameer AA, Antioxidant activity of Bahraini date palm (Phoenixdactylifera L.) fruit of various cultivars. Int J Food Sci Technol43:10331040 (2008).

62 Ali A and Abdu S, Antioxidant protection against pathologicalmycotoxins alterations on proximal tubules in rat kidney. FunctFoods Health Dis 4:118134 (2011).

63 Saafi EB, Louedi M, Elfeki A, Zakhama A, Najjar MF, Hammami M, et al.,Protective effect of date palm fruit extract (Pheonix dactylifera L.)on dimethoate induced-oxidative stress in rat liver. Exp ToxicolPathol 63:433441 (2011).

64 Pujari RR, Vyawahare NS and Kagathara VG, Evaluation of antioxidantand neuroprotective effect of date palm (Phoenix dactylifera L.)against bilateral common carotid artery occlusion in rats. Indian JExp Biol 49:627633 (2011).

65 Karasawa K, Uzuhashi Y, Hirota M and Otani H, A matured fruit extractof date palm tree (Phoenix dactylifera L.) stimulates the cellularimmune system in mice. J Agric Food Chem 59:1128711293(2011).

66 Chaira N, Smaali MI, Martinez-Tome M, Mrabet A, Murcia MA andFerchichi A, Simple phenolic composition, flavonoid contentsand antioxidant capacities in water-methanol extracts of Tunisiancommon date cultivars (Phoenix dactylifera L.). Int J Food Sci Nutr60:316329 (2009).

67 Yeh CT, Ching LC and Yen GC, Inducing gene expression of cardiacantioxidant enzymes by dietary phenolic acids in rats. J NutrBiochem 20:163171 (2009).

68 Steinbrenner H and Sies H, Protection against reactive oxygen speciesby selenoproteins. Biochim Biophys Acta 1790:14781485 (2009).

69 Ferguson LR, Philpott M and Karunasinghe N, Dietary cancer andprevention using antimutagens. Toxicology 198:147159 (2004).

70 Vinson JA, Zubik L, Bose P, Samman N and Proch J, Dried fruits:excellent in vitro and in vivo antioxidants. J Am Coll Nutr 24:4450(2005).

71 Ranilla LG, Kwon YI, Genovese MI, Lajolo FM and ShettyK, Antidiabetes and antihypertension potential of commonlyconsumed carbohydrate sweeteners using in vitro models. J MedFood 11:337348 (2008).

72 Rock W, Rosenblat M, Borochov-Neori H, Volkova N, JudeinsteinS, Elias M, et al., Effects of date (Phoenix dactylifera L., Medjoolor Hallawi variety) consumption by healthy subjects on serumglucose and lipid levels and on serum oxidative status: a pilotstudy. J Agric Food Chem 57:80108017 (2009).

73 Chaira N, Ferchichi A, Mrabet A and Sghairoun M, Chemicalcomposition of the flesh and the pit of date palm fruit andradical scavenging activity of their extracts. Pakistan J Biol Sci10:22022207 (2007).

74 Asadi-Shekaari M, Rajabalian S, Gholamhoseinian A, Ganjooei NA,Hoseini R and Mahmoodi M, Protective effect of aqueous extractof date fruit against in vitro H2O2-induced cell damages. Curr TopNutraceut Res 6:99103 (2008).

75 Vayalil PK, Antioxidant and antimutagenic properties of aqueousextract of date fruit (Phoenix dactylifera L. Arecaceae). J Agric FoodChem 50:610617 (2002).

76 Carvalho ALN, Annoni R, Silva PRP, Borelli P, Fock RA, TrevisanMTS, et al., Acute, subacute toxicity and mutagenic effects ofanacardic acids from cashew (Anacardium occidentale Linn.) inmice. J Ethnopharmacol 135:730736 (2011).

77 Rahden-Staron I, Suchocki P and Czeczot H, Evaluation of mutagenicactivity of the organo-selenium compound Selol by use of theSalmonella typhimurium mutagenicity assay. Mutat Res GenetToxicol EnvironMutagen 699:4446 (2010).

78 Aremu AO, Amoo SO, Ndhlala AR, Finnie JF and Staden JV, Antioxidantactivity, acetylcholinesterase inhibition, iridoid content andmutagenic evaluation of Leucosidea sericea. Food Chem Toxicol49:11221128 (2011).

79 Birosova L, Mikulasova M and Vaverkova S, Antimutagenic effect ofphenolic acids. Biomed Papers 149:489491 (2005).

80 Mohammed DA and Al-Okbi SY, In-vivo evaluation of antioxidantand anti-inflammatory activity of different extracts of date fruits inadjuvant arthritis. Pol J Food Nutr Sci 13:397402 (2004).

81 Adiba BD, Salem B, Nabil S and Addelhakim M, Preliminarycharacterization of food tablets from date (Phoenix dactylifera L.)and spirulina (Spirulina sp.) powders.PowderTechnol208:725730(2011).

82 Gescher A, Polyphenolic phytochemicals versus non-steroidal anti-inflammatory drugs: which are better cancer chemopreventiveagents? J Chemother 16:36 (2004).

83 Al-Mamary M, Al-Habori M and Al-Zubairi AS, The in vitro antioxidantactivity of different types of palm dates (Phoenixdactylifera) syrups.Arab J Chem (2010). DOI: 10.1016/j.arabjc.2010.11.014 in press.

84 Al-Qarawi AA, Abdel-Rahman H, Ali BH, Mousa HM and El-Mougy SA,The ameliorative effect of dates (Phoenix dactylifera L.) on ethanol-induced gastric ulcer in rats. J Ethnopharmacol 98:313317 (2005).

85 Al-Qarawi AA, Ali BH, El-Mougy SA and Mousa HM, Gastrointestinaltransit in mice treated with various extracts of date (Phoenixdactylifera L.). Food Chem Toxicol 41:3739 (2003).

86 Iwasaki Y, Matsui T and Arakawa Y, The protective and hormonaleffects of proanthocyanidin against gastric mucosal injury in Wistarrats. J Gastroenterol 39:831837 (2004).

87 Mota KS, Dias GE, Pinto ME, Luiz-Ferreira A, Souza-Brito AR, Hiruma-Lima CA, et al., Flavonoids with gastroprotective activity. Molecules14:9791012 (2009).

88 Li CY, Xu HD, Zhao BT, Chang HI and Rhee HI, Gastroprotective effectof cyanidin 3-glucoside on ethanol-induced gastric lesions in rats.Alcohol 42:683687 (2008).

89 Ipatova OM, Prozorovskaia NN, Rusina IF and ProzorovskiVN, Antioxidant properties of a leaf extract from aronia(Aroniamelanocarba) containing proanthocyanidins. BiomedKhim49:165176 (2003).

90 Al-Qarawi AA, Abdel-Rahman H, Ali BH, Mousa HM and El-Mougy SA,Protective effect of extracts from dates (Phoenix dactylifera L.) oncarbon tetrachloride-induced hepatotoxicity in rats. Int J Appl ResVet Med 3:176180 (2004).

91 Zheng QS, Sun XL, Xu B, Li G and Song M, Mechanisms of apigenin-7-glucoside as a hepatoprotective agent. Biomed Environ Sci18:6570 (2005).

92 Srinivasan M, Rukkumani R, Ram Sudheer A and Menon VP, Ferulicacid, a natural protector against carbon tetrachloride-inducedtoxicity. Fund Clin Pharmacol 19:491496 (2005).

93 Janbaz KH, Saeed SA and Gilani AH, Studies on the protective effectsof caffeic acid and quercetin on chemical-induced hepatotoxicityin rodents. Phytomedicine 11:424430 (2005).

94 Domitrovic R, Jakovac H, Grebic D, Milin C and Radosevic-Stasic B, Dose- and time-dependent effects of luteolin on livermetallothioneins and metals in carbon tetrachloride-inducedhepatotoxicity in mice. Biol Trace Elem Res 126:176185 (2008).

95 Al-Qarawi AA, Abdel-Rahman H, Mousa HM, Ali BH and El-MougySA, Nephroprotective action of Phoenix dactylifera in gentamicin-induced nephrotoxicity. Pharmaceut Biol 46:227230 (2008).

96 Abdel-Raheem IT, Abdel-Ghany AA and Mohamed GA, Protectiveeffect of quercetin against gentamicin-induced nephrotoxicity inrats. Biol Pharmaceut Bull 32:6167 (2009).

97 Siddiqi N, El Shahat O, Bokhari E, Haytham Roujouleh H, Hamid H,Sheikh I, et al., The effect of use of dates on serum potassiumin no diabetic hemodialysis patients. Saudi J Kidney Dis Transpl20:10181022 (2009).

98 El-Mougy SA, Abdel-Aziz SA, Al-Shanawany M and Omar A, Thegonadotropic activity of Palmae in mature male rats. Alexandria JPharmaceut Sci 5:156159 (1991).

99 Eustache F, Mondon F, Canivenc-Lavier MC, Lesaffre C, FullaY, Berges R, et al., Chronic dietary exposure to a low-dosemixture of genistein and vinclozolin modifies the reproductiveaxis, testis transcriptome, and fertility. Environ Health Perspect117:12721279 (2009).

100 Said L, Banni M, Kerkeni A, Said K and Messaoudi I, Influence ofcombined treatment with zinc and selenium on cadmium induced


2361


testicular pathophysiology in rat.FoodChemToxicol48:27592765(2010).

101 Jana K, Samanta PK, Manna I, Ghosh P, Singh N, Khetan RP,et al., Protective effect of sodium selenite and zinc sulfateon intensive swimming-induced testicular gamatogenic andsteroidogenic disorders in mature male rats. Appl Physiol NutrMetabol 33:903914 (2008).

102 Puri A, Sahai R, Singh KL, Saxena RP, Tandon JS and Saxena KC,Immunostimulant activity of dry fruits and plant materials used inIndian traditional medical system for mothers after childbirth andinvalids. J Ethnopharmacol 71:8992 (2000).

103 Ishurd O and Kennedy JF, The anti-cancer activity of polysaccharideprepared from Libyan dates (Phoenix dactylifera L.). CarbohydrPolym 59:531535 (2005).

104 Farvid MS, Siassi F, Jalali M, Hosseini M and Saadat N, The impact ofvitamin and/or mineral supplementation on lipid profiles in type2 diabetes. Diabetes Res Clin Pract 65:2128 (2004).

105 Karppi J, Nurmi T, Kuri S, Rissanen TH and Nyyssonen K, Lycopene,lutein and -carotene as determinants of LDL conjugated dienesin serum. Atherosclerosis 209:565572 (2010).

106 Dembinska-Kiec A, Mykkanen O, Kiec-Wilk B and Mykkanen H,Antioxidant phytochemicals against type 2 diabetes. Br J Nutr99:ES109ES117 (2008).

107 Manach C, Mazur A and Scalbert A, Polyphenols and prevention ofcardiovascular diseases. Curr Opin Lipidol 16:7784 (2005).

108 Bhathena SJ and Velasquez MT, Beneficial role of dietaryphytoestrogens in obesity and diabetes. Am J Clin Nutr76:11911201 (2002).

109 Choi MS, Jung UJ, Yeo J, Kim MJ and Lee MK, Genistein and daidzeinprevent diabetes onset by elevating insulin level and alteringhepatic gluconeogenic and lipogenic enzyme activities in non-obese diabetic (NOD) mice. Diabetes Metabol Res Rev 24:7481(2008).

110 Weickert MO and Pfeiffer AFH, Metabolic effects of dietary fiberconsumption and prevention of diabetes. J Nutr 138:439442(2008).

111 Braga FC, Serra CP, Viana NS, Oliveira AB, Cortes SF and LombardiJA, Angiotensin-converting enzyme inhibition by Brazilian plants.Fitoterapia 78:353358 (2007).

112 Macdonald JE and Struthers AD, What is the optimal serum potassiumlevel in cardiovascular patients? J Am Coll Cardiol 43:155161(2004).

113 He FL and MacGregor GA, Beneficial effects of potassium on humanhealth. Physiol Plant 133:725735 (2008).

114 Alsaif MA, Khan LK, Alhamdan AAH, Alorf SM, Harfi SH, Al-Othman AM,et al., Effect of dates and gahwa (Arabian coffee) supplementationon lipids in hypercholesterolemic hamsters. Int J Pharmacol3:123129 (2007).

115 John S, Sorokin AV and Thompson PD, Phytosterols and vasculardisease. Curr Opin Lipidol 18:3540 (2007).

116 Batta AK, Xu G, Honda A, Miyazaki T and Salen G, Stigmasterol reducesplasmacholesterol levels and inhibits hepatic synthesis and intestinalabsorption in the rat. Metabolism 55:292299 (2006).

117 Temme EH, Van Hoydonck PG, Schouten EG and Kesteloot H, Effectsof a plant sterol-enriched spread on serum lipids and lipoproteins

in mildly hypercholesterolaemic subjects.ActaCardiol57:111115(2002).

118 Shi J, Ho C and Shahid F, Asian Functional Foods. CRC Press, New York,NY, pp. 508516 (2005).

119 Kulkarni SG, Vijayanand P and Shubha L, Effect of processing ofdates into date juice concentrate and appraisal of its qualitycharacteristics. J Food Sci Technol 47:157161 (2010).

120 Abbes F, Kchaou W, Blecker C, Ongena M, Lognay G, Attia H,et al., Effect of processing conditions on phenolic compounds andantioxidant properties of date syrup. Ind Crop Prod 44:634642(2013). DOI: 10.1016/j.indcrop.2012.09.008.

121 El-Sharnouby GA, Al-Eid SM and Al-Otaibi MM, Utilization of enzymesin the production of liquid sugar from dates. Afr J Biotechnol Res3:4147 (2009).

122 Gohari-Ardebili A, A survey on effects of replacement of sugar withdate syrup on physico-chemical characteristics of soft ice cream.MSc Thesis, Faculty of Agriculture, Ferdosi University, Mashhad(2004).

123 Ahmed J and Ramaswamy HS, Physico-chemical properties ofcommercial date pastes (Phoenix dactylifera). J Food Eng76:348352 (2006).

124 Sanchez-Zapata E, Fernandez-Lopez J, Penaranda M, Fuentes-Zaragoza E, Sendra E, Sayas E, et al., Technological propertiesof date paste obtained from date by-products and its effect onthe quality of a cooked meat product. Food Res Int 44:24012407(2011).

125 Acourene S, Djafri K, Ammouche A, Djidda A, Tama M and Taleb B,Utilisation of the date wastes as substrate for the production ofbakers yeast and citric acid. Biotechnology 10:488497 (2011).

126 Chauhan K, Trivedi U and Patel KC, Statistical screening of mediumcomponents by PlackettBurman design for lactic acid productionby Lactobacillus sp. KCP01 using date juice. Bioresour Technol98:98103 (2007).

127 Moosavi-Nasab M and Yousefi A, Biotechnological production ofcellulose by Gluconacetobacter xylinus from agricultural waste.Iran J Biotechnol 9:94101 (2011).

128 Moosavi-Nasab M, Shekaripour F and Alipoor M, Use of date syrupas agricultural waste for xanthan production by Xanthomonascampestris. Iran Agric Res 28:8997 (2009).

129 Radwan H, Alanazi FK, Taha EI, Dardir HA and Moussa IM,Development of a new medium containing date syrup forproduction of bleomycin byStreptomycesmobaraensisATCC 15003using response surface methodology.AfrJBiotechnol9:54505459(2010).

130 Al-Jasass FM, Aleid SM and Ali SHH, A comparative study on datesyrup (dips) as substrate for the production of bakers yeast(Saccharomyces cerevisiae). J Food Agric Environ 8:314316 (2010).

131 Masmoudi M, Besbes S, Blecker C and Attia H, Preparation andcharacterization of jellies with reduced sugar content from date(Phoenix dactylifera L.) and lemon (Citrus limon L.) by-products.Fruits 65:2129 (2010).

132 Al-Shoaibi Z, Al-Mamary MA, Al-Habori MA, Al-Zubairi AS andAbdelwahab SI, In vivo antioxidative and hepatoprotective effectsof palm date fruits (Phoenix dactylifera). Int J Pharamcol 8:185191(2012).


date fruit (chemical composition,nutritional, and medicinal values, products

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