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2016
ANTIMICROBIAL ACTIVITY OF STAR ANISE,
ANISEED AND CINNAMON AGAINST FOODBORNE
BACTERIA
NIK NOR FATIN BINTI ROZIK
MASTER OF SCIENCE
2016
Antimicrobial Activity of Star Anise, Aniseed and
Cinnamon Against Foodborne Bacteria
by
Nik Nor Fatin Binti Rozik
A thesis submitted in fulfillment of the requirements for the degree of
Master of Science
Faculty of Veterinary Medicine
UNIVERSITI MALAYSIA KELANTAN
i
THESIS DECLARATION
I hereby certify that the work embodied in this thesis is the result of the original
research and has not been submitted for a higher degree to any other University or
Institution.
OPEN ACCESS
EMBARGOES
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I agree that my thesis is to be made immediately available
as hardcopy or on-line open access (full text).
I agree that my thesis is to be made available as hardcopy
or on-line (full text) for a period approved by the Post
Graduate Committee.
Dated from _ until
(Contains confidential information under the office
Official Secret Act 1972)*
(Contains restricted information as specified by the
organization where research was done)*
I acknowledge that Universiti Malaysia Kelantan reserves the right as follows.
1. The thesis is the property of Universiti Malaysia Kelantan.
2. The library of Universiti Malaysia Kelantan has the right to make copies for the
purpose of research only.
3. The library has the right to make copies of the thesis for academic exchange.
SIGNATURE SIGNATURE OF SUPERVISOR
IC/ PASSPORT NO. NAME OF SUPERVISOR
Date: Date:
ii
ACKNOWLEDGEMENTS
In the name of Allah, the Most Gracious and Most Merciful. Alhamdulillah, all praises
to Allah S.W.T for giving me strength to face all challenges and problems in
accomplishing my thesis project succesfully.
First and foremost, special thanks to my parents (Rozik Abas & Tuan Norizan Tuan
Soh), my beloved husband (Nik Mohd Hafizuddin Mohd Zuhdi) and family for giving
me their continuos support, pray and encouragement. To my dedicated supervisor, AP
Dr. Mohd Mokhtar Arshad, thank you for the advised and guidance in completing my
thesis project. I would like to show my gratitute to my co-supervisor, Datin Prof. Dr.
Kalthum Hashim, FPV lecturers especially to Prof. Dr. Wan Zahari Bin Mohamed and
Dr. Erkihun Aklilu Woldegiorgis and committee for the helps and guidancesv. Special
appreciations goes to Miss Nani Izreen, Miss Siti Rokiah, Miss Ain Basirah and other
laboratory staffs, without them, this study would not have been successful.
Last but not least, I would like to thank my beloved friends (Nurul Afiqah, Nur
Fadhilah, Suhaily Suhana, Ain Auzureen and Nadiah) for giving me help and support
without any hesitation. Lastly, thanks to those who have directly or indirectly involved
in helping me to finish my thesis project succesfully.
iii
TABLE OF CONTENTS
PAGE
THESIS DECLARATION i
ACKNOWLEDGEMENT ii
TABLE OF CONTENT iii
LIST OF TABLES vi
LIST OF FIGURES viii
LIST OF ABBREVIATIONS ix
LIST OF SYMBOLS x
ABSTRAK xi
ABSTRACT xii
CHAPTER 1 INTRODUCTION 1
1.1 General Introduction 1
1.2 Problem Statement 4
1.3 Research Question 5
1.4 Hypothesis 5
1.5 Objectives 5
1.6 Significance of Research 6
CHAPTER 2 LITERATURE REVIEW 7
2.1 Spices 7
2.1.1 Star anise 8
iv
2.1.2 Aniseed 11
2.1.3 Cinnamon 13
2.2 Foodborne Illness 15
2.3 Foodborne Bacteria 19
2.4 Extraction of Essential Oil From Spices 24
CHAPTER 3 MATERIALS AND METHODS 27
3.1 Spices 27
3.2 Preparation of Crude Extract 27
3.3 Tested and Control Bacteria 28
3.4 Antimicrobial Activity of Crude Extraction by Agar Diffusion Method 28
3.5 Statistical Analysis 29
3.6 Extraction of Essential Oils 29
3.7 Antimicrobial Activity of Essential Oils using Hole Plate Agar 30
Diffusion Method
3.8 Minimal Inhibitory Concentration of Essential Oil 31
3.9 Decontaminating Chicken Carcasses 31
CHAPTER 4 RESULTS 33
4.1 Result of Antimicrobial Activity of Crude Extract by Agar Diffusion 33
Method
4.2 Result of Antimicobial Activity of Essential Oils Extract using Hole 42
Plate Agar Method
4.3 Result of Minimal Inhibitory Concentration of Essential Oils 49
4.4 Result of Decontaminating Chicken Carcasses 50
v
CHAPTER 5 DISCUSSION 51
5.1 Crude Extract 51
5.2 Essential Oils Extract 54
CHAPTER 6 CONCLUSION AND RECOMMENDATION 59
REFERENCES 61
APPENDIX A 69
APPENDIX B 73
vi
LIST OF TABLES
NO. PAGE
3.1 Diameter of zone of inhibition according sensitivity 29
against bacteria
4.1.1 Mean diameter of inhibition zone of different concentration 34
of extracts and method of extraction of star anise against
Salmonella Typhimurium
4.1.2 Mean diameter of inhibition zone of different concentration 35
of extracts and method of extraction of star anise against
Staphylococcus aureus
4.1.3 Mean diameter of inhibition zone of different concentration 36
of extracts and method of extraction of star anise against
Escherichia coli
4.1.4 Mean diameter of inhibition of different concentration of extracts 37
and method of extraction of star anise against S. aureus
ATCC 6538
4.1.5 Mean diameter of inhibition of different concentration of extracts 38
and method of extraction of star anise against
Escherichia coli ATCC 25922
4.1.6 Mean diameter of inhibition of different concentration of extracts 39
and method of extraction of star anise against
Salmonella Typhimurium ATCC 14028
4.1.7 Mean diameter of inhibition of different concentration of extracts 40
and method of extraction of cinnamon against S.aureus
4.1.8 Mean diameter of inhibition of different concentration of extracts 41
and method of extraction of cinnamon against S. aureus
ATCC 6538
4.2.1 Mean diameter of zone of inhibition of essential oil of different 43
spices against E. Coli
4.2.2 Mean diameter of zone of inhibition of essential oil of different 44
spices against E. coli ATCC 25922
4.2.3 Mean diameter of zone of inhibition of essential oil of different 45
spices against S. aureus
4.2.4 Mean diameter of zone of inhibition of essential oil of different 45
spices against S. aureus ATCC 6538
vii
4.2.5 Mean diameter of zone of inhibition of essential oil of different 46
spices against S. Enteritidis
4.2.6 Mean diameter of zone of inhibition of essential oil of different 47
spices against S.Typhimurium ATCC 14028
4.2.7 Mean diameter of zone of inhibition of essential oil of different 48
spices against S.Typhimurium
4.3 Mnimal Inhibitory Concentration of essential oil of different 49
spices against different bacteria
4.4 Mean total plate count for decontamination of chicken meat 50
viii
LIST OF FIGURES
NO.
2.1
Star anise (Illicium verum)
PAGE
9
2.2 Aniseed (Pimpinella anisum) 11
2.3 Cinnamon (Cinnamomun verum) 14
ix
LIST OF ABBREVIATIONS
µ g Microgram
µ L Microlitre
ANOVA Analysis of Variance
ATCC American Type Culture Collection
CFU Colony Form Unit
mL Mililitre
mg Miligram
MIC Minimal Inhibitory Concentration
SD Standard deviation
DIZ Diameter of inhibition zone
mm Milimetre
HIV Human immunodeficiency virus
EO Essential oils
g Gram
mbar Milibars
MHA Mueller hinton agar
DMSO Dimethyl sulfoxide
TPC Total plate count
Eh Oxidation-reduction potential
h Hour
GRAS Generally recognized as safe
x
LIST OF SYMBOLS
ºC Degree Celsius
% Percentage
xi
Aktiviti Antimikrob Bunga Lawang, Jintan Manis dan Kulit Kayu Manis
Terhadap Bakteria Bawaan Makanan
ABSTRAK
Salmonella spp, Escherichia coli and Staphylococcus aureus adalah bakteria yang
kebiasaannya terlibat dalam pencemaran daging ayam, sehingga menyebabkan wabak
keracunan makanan. Bahan kimia sering digunakan sebagai bahan pengawet untuk
mengurangkan pencemaran bakteria. Objektif kajian ini adalah untuk mengetahui
aktiviti antimokrob ekstrak mentah dan pati minyak dari jintan manis, bunga lawang
dan kayu manis terhadap bakteria bawaan makanan dan menialai potensi dekontaminasi
pati minyak ke atas daging ayam. Air, etanol dan metanol digunakan untuk
menghasilkan ekstrak mentah jintan manis, bunga lawang dan kayu manis. Pati minyak
dihasilkan menggunakan radas ‘Soxhlet’. Aktiviti antimikrob ditentukan dengan
menguji ekstrak mentah dan pati minyak ke atas Salmonella spp, E. coli and S. aureus
menggunakan “agar well diffusion assay”. “Minimal inhibitory concentration (MIC)”
pati minyak ditentukan menggunakan kaedah “microtitre broth dilution”. Aktiviti
dekontaminasi pati minyak ditentukan dengan menjalankan ujian “total plate count
(TPC)” ke atas daging ayam sebelum dan selepas dirawat dengan 0.1%, 0.5% and 1.0%
pati minyak. Ekstrak air dari bunga lawang menghasilkan diameter zon perencatan
paling panjang ke atas S. aureus (12.33 mm) berbanding dengan ekstrak etanol dan
metanol pada kepekatan 200 mg/mL. Ekstrak etanol dan metanol kayu manis
menghasilkan diameter zon perencatan yang sama ke atas S. aureus (15.67mm). Pati
minyak kayu manis menghalang pertumbuhan E. coli pada semua kepekatan yang
digunakan. Pati minyak bunga lawang menghalang pertumbuhan E.coli pada kepekatan
80% (purata diameter zon perencatan = 9.33 mm) and 100% (purata diameter zon
perencatan = 11.67 mm). Pati minyak jintan manis tidak menghalang pertumbuhan S.
Enteritidis pada semua kepekatan yang digunakan. Pati minyak kayu manis menghalang
pertumbuhan S. Enteritidis pada semua kepekatan yang digunkan. Pati minyak bunga
lawang menghalang pertumbuhan S. Enteritidis pada kepekatan 80% and 100%. MIC
jintan manis ke atas S. aureus dan S. aureus ATCC 6538 adalah 0.6 µ g/µ l. MIC paling
rendah pati minyak bunga lawang adalah 0.08 µ g/µ l ke atas S. aureus dan yang paling
tinggi adalah 0.8 µ g/µ l ke atas E. coli, S. Typhimurium dan E. coli ATCC 25922. MIC
kayu manis mempunyai MIC yang rendah (0.02 µ g/µ l) ke atas S. aureus dan S. aureus
ATCC 6538 dan MIC yang tinggi ke atas S. Enteritidis (0.1 µ g/µ l). Selepas dirawat
dengan 1.0% pati minyak selama 24 jam “TPC” daging ayam berkurangan dari 6.14
log CFU/mL kepada 5.28 log CFU/mL bagi jintan manis, kepada 5.16 log CFU/mL
bagi bunga lawang dan kepada 5.04 log CFU/mL bagi kayu manis. Kesimpulan nya
kajian ini menunjukkan pati minyak dari rempah yang digunakan mempunyai aktiviti
antimikrob yang lebih baik dari ekstrak mentah.
xii
Antimicrobial Activity of Star Anise, Aniseed and Cinnamon against Foodborne
Bacteria
ABSTRACT
Salmonella spp, Escherichia coli and Staphylococcus aureus frequently contaminate
chicken meat and result in outbreaks of food poisoning. Chemical preservatives were
commonly used to reduce bacterial contamination.The objectives of this study wereto
determine the antimicrobial activity of the crude extracts and essential oil of aniseed,
cinnamon and star anise against foodborne bacteria and to evaluate the decontamination
potential of the essential oil of the spices on chicken meat. Crude extract of star anise,
aniseed and cinnamon were extracted using water, ethanol and methanol. Essential oils
were extracted using Sohxlet apparatus. Antimicrobial activity was determine by testing
the crude extracts and essential oils against Salmonella spp, E. coli and S. aureus using
agar well diffusion assay. Minimal inhibitory concentration (MIC) of essential oil was
determined by microtitre broth dilution method. Decontamination activity of the
essential oil was determined using total plate count (TPC) of chicken meat before and
after treatment with the 0.1%, 0.5% and 1.0% essential oils. Aqueous extract of star
anise had the highest mean of inhibition zone against S. aureus (12.33 mm) compared to
ethanol and methanol extract. Ethanol and methanol extracts of cinnamon gave the same
mean of inhibition zone (15.67 mm) against S. aureus. Essential oil of cinnamon
inhibited the growth of E. coli at all the tested concentration and essential oil of star
anise inhibited E. coli at the concentration of 80% (mean diameter of zone of
inhibition= 9.33 mm) and 100% (mean diameter of inhibition zone = 11.67 mm).
Aniseed oil did not inhibited growth S. Enteritidis at all concentration but cinnamon oil
inhibited the growth of S. Enteritidis at all concentration tested while star anise oil
inhibited S. Enteritidis at the concentration of 80% and 100% respectively. MIC of
aniseed against S. aureus and S. aureus ATCC 6538 was 0.6 µ g/µ l. The lowest MIC of
essential oil of star anise was 0.08 µ g/µ l against S. aureus and the highest was 0.8 µ g/µ l
against E. coli, S. Typhimurium and E. coli ATCC 25922. Cinnamon oil had the lowest
MIC which is 0.02 µ g/µ l against S. aureus and S. aureus ATCC 6538 where its highest
value was against S. Enteritidis which is 0.1 µ g/µ l. After being treated with 1.0%
essential oil for 24h the TPC of the chicken meat reduced from 6.14 log CFU/mL to
5.28 log CFU/mL for aniseed, to 5.16 log CFU/mL for star anise and to 5.04 log
CFU/mL for cinnamon. In conclusion, this study showed that the essential oils of the
spices had better antimicrobial activity compared to the crude extracts.
1
CHAPTER 1
INTRODUCTION
1.1 General Introduction
Consumer demand for food rises yearly. In order to meet the demand,
many food are locally produced and processed locally under very intensive
production and processing systems. In addition, food are also imported from
foreign countries. During the production, processing and importation, the food
can be contaminated with microorganisms, resulting in foodborne illness in
humans, if they are not stored, processed and cooked properly (Beuchat & Ryu,
1997).
The globalization of the food industry has resulted in increased cases of
foodborne illness due to the unhygienic condition present during processing and
handling of food, along with workers involved in the production line. People
who are busy and live a hectic lifestyle often dine at fast food outlets or
restaurants. These eateries generally have many people involved in preparing
and handling the food, thus increasing the chance of contamination resulting in
foodborne illness (Abdul-Mutalib, Syafinaz, Sakai & Syirai, 2015).
Microorganisms which are already known to cause foodborne disease can appear
in a new way, for example, new form of infection associated with new food, or
2
found in a new geographical location, as well as changes in microbial genotypes.
(Altekruse, Cohen & Swerdlow, 1997).
About 76 million cases of foodborne illness occur every year in the
United States. Roughly, about 30% from 13.8 million cases occurred due to
bacterial contamination (McEntire, 2004). In 2002, more than 100 possible
foodborne and waterborne outbreaks have been investigated by the Illinois
Department of Public Health (IDPH) and local health departments. Ninety-one
were classified as foodborne outbreaks; 24 outbreaks were laboratory confirmed;
38 outbreaks were characteristic of a particular foodborne pathogen; and 29
outbreaks were of unknown origin. Salmonella was the cause of six outbreaks
while Escherichia coli O157:H7 accounted for three outbreaks (Austin, 2004).
Consumption of chicken and chicken products caused a high number of acute
Campylobacter enteritis or campylobacteriosis in humans (CDC, 2005).
Malaysia had a lower number of cases of foodborne diseases compared to
other countries owing to unreported cases as the affected persons had a minor
bacterial infection therefore had not sought treatment at the hospitals (Abdul-
Mutalib et al, 2015). Foodborne illness occured in schools were reported
because the students were treated at hospitals while incidences that involve
people who ate at food stores or restaurants were hardly detected as some of
them received treatment from private clinics and hospitals (Lim, 2002).
About 50% of foodborne cases occurred in Malaysia are due to
unhygienic food handling procedures (Abdul-Mutalib et al, 2015; Sharifa Ezat,
2013). Bacterial pathogens commonly isolated were non-typhoidal Salmonella
3
(57%), Aeromonas spp. (4%), Shigella spp. (11%), enteropathogenic E. coli
(EPEC) (14%) and Campylobacter spp. (5%) (Lim, 2002).
Acute food poisoning symptoms caused by foodborne bacteria include
nausea, vomiting, fever, abdominal pain, and diarrhea or bloody diarrhea. The
foodborne illness may also lead to chronic or long- lasting health problem such
as dehydration, Guillain-Barre syndrome, Reiter’s syndrome and Hemolytic
uremic syndrome (Marler, 2011).
Nowadays, consumers demand for more ready-to- cook and ready- to-eat
foods that are of high quality, long shelf-life and safe. Controlling microbial
growth can reduce the occurrence of food spoilage and food poisoning. One of
the methods is by using chemical preservatives on ready-to-cook and ready-to-
eat food. Pathogenic bacteria are inhibited by these chemical preservatives.
However, consumers nowadays are more inclined to use natural preservatives
instead of chemical ones. This is because continuous use of chemical
preservatives may result in residual toxicity and microbial resistance and may be
carcinogenic, which are health risks to consumers. Food were introduced with
synthetic chemicals in order to control deterioration caused by bacteria and also
used to alter the palatability of the food (Ozcan & Erkmen, 2001)
Natural sources of antimicrobial compound have been tested such as
essential oils from herbs or spices to replace the use of chemicals in food
preservatives. Many researchers have found natural substances that have a good
antimicrobial activity (Ead, Jangchud, Chonhenchob & Suppakul, 2006; Bin, Yi,
Brooks & Corke, 2007). Spices and herbs are some natural substances that
4
posses antimicrobial activity. Microbial resistance do not exist due to differences
of mechanism of actions in essential oils. They were also considered as
Generally Recognized as Safe (GRAS) by U. S. Food and Drug Administration
and safe for human consumption (Dobre, Gagiu & Petru, 2011).
Extracts of the spices exhibited antimicrobial activity towards
microorganism due to their secondary metabolites and can be utilised in food
industries to replace the chemical preservatives used in reducing food poisoning
and spoilage during food production. In this research, antimicrobial effect of
extracts from star anise, aniseed and cinnamon were evaluated against
Staphylococcus aureus, Salmonella Typhimurium, Salmonella Enteritidis, and
Escherichia coli.
1.2 Problem Statement
Foodborne bacteria such as Salmonella spp. and Campylobacter jejuni
are the common causes of food poisoning. Chicken meats are frequently
reported as the source of outbreak caused by bacterial contamination. Chemical
preservatives had been included in ready-to-cook and ready-to-eat food in order
to inhibit the growth of the undesirable bacteria. However, consumers nowadays
are more discerning to use natural preservatives instead of chemical. This is
because the continuous use of chemical preservatives may result in residual
toxicity and microbial resistance and may be carcinogenic, which are health
risks to consumers. Antimicrobial compound from natural sources such as
5
essential oils from herbs or spices can be used as natural preservatives in ready-
to-cook or ready-to-eat food.
In Malaysia, spices such as star anise, aniseed and cinnamon are
frequently used for cooking and are easily available in the market. However,
their antimicrobial activities against foodborne bacteria such as Salmonella spp,
Staphylococcus aureus and Escherichia coli have not been investigated.
1.3 Research Question
Do star anise, aniseed and cinnamon possess antimicrobial activity against
foodborne bacteria?
1.4 Hypothesis
Crude extracts and essential oil of star anise, aniseed and cinnamon possess
antimicrobial activity against foodborne bacteria such as Salmonella spp,
Staphylococcus aureus and Escherichia coli.
1.5 Objectives
To determine the antimicrobial activity of star anise, aniseed and cinnamon
extracts against foodborne bacteria.
6
To determine in vitro the minimal inhibitory concentration (MIC) of the
essential oil extracts against foodborne bacteria.
To evaluate the decontamination potential of essential oil from star anise on
chicken meat.
1.6 Significance of Research
The results of the research can help food producers to choose natural
preservatives to preserve ready-to-cook and ready-to-eat foods that they
manufacture in order to inhibit the growth of foodborne bacteria.
7
CHAPTER 2
LITERATURE REVIEW
2.1 Spices
Spices are plants that possess antimicrobial properties, medicative
properties and have stimulating effects in the animal digestive system (Rahman,
Parveez, Islam & Khan, 2011). The spices have been used in Europe, the Middle
East and Asia for thousands of years. Shelf life of vegetables, fishes, breads and
meats were prolonged using spices before refrigeration methods came to
existance. Spices were used in foods as seasonings, preservatives, food
additives, flavor enhancer and aroma and appetizing effects. Deterioration and
spoilage of food can be reduced by using spices together with pickling smoking,
and salting in order to extend shelf life of food (Bin et al., 2007).
Previous studies confirmed that growth of Gram-positive and Gram-
negative foodborne and food spoilage bacteria were inhibited by cinnamon, sage,
onion, cloves, garlic, thyme, and other spices (Hoque, Bari, Juneja &
Kawamoto, 2008). Ertuk (2006) reported that extracts of the spices were
effective against bacteria compared to fungi. Powders, extracts and essential oils
of various herbs and spices had antimicrobial activity and inhibited aflatoxin
formation by fungus ( Thanaboripat, Suvathi, Srilohasin & Sripakdee, 2007).
8
Antimicrobial activity of spices depends on the type of spice, and on the
condition of the spices when added upon, such as fresh, dried or extracted form.
It may also vary between strains within the same species and also depends on
storage conditions, geographical sources, processing and harvesting season, its
composition and concentration used (Hoque et al., 2008; Rahman et al., 2011).
Antimicrobial activity of spices is affected by the type and concentrations of the
targeted bacteria and its substrate composition. Bioactive compound that posses
antimicrobial potency in spices are essential oils, phenolic compounds, tannins,
saponins and flavonoids (Rahman et al., 2011).
2.1.1 Star Anise (Illicium verum)
Star Anise or also known as Illicium verum is native spice of China,
which is the main ingredient in Chinese five-spice blend, and possess important
roles in food flavoring. Star anise is an uneven star-shaped fruit with a central
core joining the eight carpels with a seed in each carpel. Star anise are used
either in pieces, dried whole shaped and in powdered form. Star anise are sun
dried since their harvesting was done before the star anise ripens and hence
green in color (Chempakam & Balaji, 2008). Compared to fennel and anise, the
hard and reddish brown carpels of star anise have more sweet, licorice-like and
strong in flavor. Used in a high concentration can lead to a bitter aftertaste.
Spicy and sweet flavors are strongly detected during the cooking process. Star
9
anise pods contain more flavors compared to their seeds but the broken pieces of
pods are less aromatic compared to the original star anise whole shape.
Figure 2.1: Star anise (Illicium verum)
Chemical components of fresh fruit pod or pericarp has 5% to 8%
essential oil, and the dried fruit pericarp has 2.5% to 3.5%, mainly anethole
(85% to 90%), limonene, phellandrene, d-terpineol, ρ-cymene, α-pinene, and
1,4-cineole. Anethole has a higher antibacterial activity compared to anisyl
acetone, anisyl alcohol, and anisyl aldehyde against Acinetobacter baumannii,
with Minimal Inhibitory Concentration (MIC) value of 0.11 mg/mL (Yang et al.,
2010). MIC values indicate that the isolated anethole is as effective as the
standard anethole in not only inhibiting bacterial growth, but also fungal and
yeast growth (De M, De K, Mukhopadhyay, Miro & Anarjee, 2001).
Yang, Hong, Li, Dong & Xing (2010) reported that 67 clinical drug-
resistant isolates, including 27 A. baumannii, 20 Pseudomonas aeruginosa, and
20 strains of methicillin-resistant Staphylococcus aureus have been affected by
extract of star anise. (Singh, Maurya, deLampasona & Catalan, 2006) stated that
both essential oil and the acetone extract of star anise exhibited a broad spectrum
10
of antifungal and antibacterial activity, including inhibitory activity against S.
aureus , P. viridicatum, Bacillus spp., Fusarium moniliforme and P. citrinum.
Tamil-flu (oseltamivir phosphate) was the antiviral drug produced from star
anise to cure the illness caused by avian influenza H5N1 strain of virus (Li &
Liu, 2000).
Confectionery industries use essential oils of star anise as a flavor in
licorice and candies while in baking industries it is used to enhance flavor of
cakes, cookies and biscuits. Heath (1981) indicated that star anise had a volatile
oil content of 8-9% in dried material and 2.5-3.5% in the fresh fruit. It has about
20% fixed oil (Dang & Sarath, 1997;Raghavan, 2007). East Asians use star anise
to relieve colic and stomach pains. They chew it after a meal to promote
digestion and fresh breath. Star anise is also used in tea to cure sore throats and
coughs. Its oil is used as an ingredient in cough lozenges (Raghavan, 2007). Star
anise are used in its original shape and also its essential oils. East Asian people
used star anise to facilitate digestion, freshen the breath by chewing the star
anise, while sore throats and coughs can be reduced by adding some star anise in
tea.
11
2.1.2 Aniseed (Pimpinella anisum)
Aniseed is originally from India and southwest Asia. It is a flowering
plant in the family Apiaceae and can grow up to 1m tall. The leaves of this
herbaceous plant are 2- 5cm long and shallowly lobed located at the base of the
plant whereas the leaves at the higher stem of the plant are divided. Aniseed has
white flowers, 3 mm diameter and is formed in thick umbels. The fruit is 3- 5
mm long and has oblong shaped dry schizocarp. Each carpel of the aniseed fruit
splits apart to form two or more parts during maturity stages (Akhtar,
Deshmukh, Bhonsle, Kshirsagar & Kolekar, 2008). Anise seeds have a sweet
licorice- like taste and is warm, fruity, and camphoraceous. Aniseed’s flavour is
more camphor-like and delicate compared to star anise and fennel.
Figure 2.2: Aniseed (Pimpinella anisum)