tannins - bogor agricultural universityanuragaja.staff.ipb.ac.id/files/2016/03/2-tannins.pdf ·...

Tannins

Anuraga Jayanegara

Department of Nutrition and Feed Technology

Outline

A. IntroductionB. StructureC. InteractionD. Analytical methodsE. Biological effectsF. Treatments/processing methods


A. Introduction

Plant secondary compounds- Do not function in primary metabolism such as biosynthesis,

biodegradation and other energy conversions of intermediary metabolism

- Do have diverse biological activities ranging from toxicity to hormonal mimicry

- May play a role in protecting plants from herbivory and disease- Examples: alkaloids, terpenes, phenolics

Tannins, definitionWater-soluble phenolic compounds that have ability to precipitate proteins


ClassificationCondensed tannin (CT, proanthocyanidins): oligomers of two or more flavan-3-ols such as catechin, epicatechin, or gallocatechin.Hydrolysable tannin (HT): consisting of a central core of carbohydrate to which phenolic carboxylic acids are bound by ester linkage.


Why plants produce phenolics?

A strategy adopted by plants to deter attack by microorganisms,

insects and higher animals.

Factors affecting tannin levels:

- Nutrient stress (N, P, K, S deficiencies)

- High light intensity

- High temperature

- Severe drought

- Tissue damage

Increase tannin

levels


Condensed tannin (CT)

Hydrolysable tannin (HT)

B. Structure


Diversity of tannin structures

Source: Mueller-Harvey (2006)

J. Sci. Food Agric. 86, 2010-2037.


Multiple hydroxyl groups: enable phenolics to form complexes

with proteins, polysachharides and minerals.

Tannin-protein complex:

1. Hydrogen bonds: free phenolic hydroxyl groups

2. Hydrophobic bonds: aromatic ring structures

3. Covalent bonds: polymerization reactions due to heating,

exposure to UV radiation and the action of polyphenol

oxidase

C. Interaction


Illustration of protein precipitation by tannins

Marangon et al. (2010)Analytica Chimica Acta 660, 110-118


D. Analytical methods

- Categorized into: (1) chemical methods, (2) protein precipitation methods, (3) gravimetric assays, (4) tannin bioassay, (5) Others.

- Chemical assays: - Total phenols and total tannins: Folin-Ciocalteu (oxidation-reduction),

ferric chloride (metal-complexing property of phenolics)- Condensed tannins: vanilin assay, butanol-HCl assay- Hydrolysable tannins: rhodanine method, HPLC

- Protein precipitation assays: ninhydrin assay, BSA method, radial diffusion assay

- Gravimetric methods: ytterbium acetate, PVPP- Tannin bioassay: in vitro gas production + PEG (e.g. Jayanegara &

Sofyan, 2008)

More detailed methods ....

Jayanegara_2008_MP_Tannin bio.pdf

14-Tannins.pdf


E. Biological effects

Negative effects:- Decreasing nutrient utilization, in particular protein utilization- Decreasing feed intake- Toxicity and death of animals

Positive effects:- Prevention of bloat- Protection of protein from rumen degradation- Mitigating methane emission- Modulation of PUFA biohydrogenation in the rumen- Controling of gastro-intestinal nematode parasites


Decreasing nutrient utilization


Toxicity problems


Prevention of bloat


Protection of protein from rumen degradation


Mitigating methane emission

Source: Morgavi et al. (2010)

Animal 4, 1024-1036

• Global warming

• Loss of energy


Evidences:- Jayanegara et al. (2009), Animal Feed Science and Technology 150, 230-

237- Jayanegara et al. (2009), Media Peternakan 32, 120-129- Jayanegara et al. (2010), Sustainable Improvement of Animal Production

and Health (Odongo, N.E., Garcia, M., Viljoen, G.J. (Eds.)), FAO, Rome, pp. 151-157

- Jayanegara et al. (2011), Animal Feed Science and Technology 163, 231-243

- Jayanegara et al. (2012), Journal of Animal Physiology and Animal Nutrition 96, 365-375

- Jayanegara et al. (online first), British Journal of Nutrition

Jayanegara_2009_AFST_Tannin method CH4.pdf

Jayanegara_2009_MP_Supl hijauan tanin CH4.pdf

Jayanegara_2010_SIAPH FAO_tannin saponin CH4.pdf

Jayanegara_2011_AFST_Trop CH4.pdf

Jayanegara_2012_JAPAN_Meta tannin CH4.pdf

Jayanegara_2012_BJN_Assoc effect CH4_OF.pdf


Source: Bhatta et al. (2009)

J. Dairy Sci. 92, 5512-5522 Phenolics and microbial population


Protozoa colonized by

methanogens

Ruminal methanogens attached to protozoal

species interspecies H transfer

Protozoa-associated methanogens contribute

up to 37% of total rumen methane emissions

Removal of protozoa from the rumen

(defaunation) may ↓ CH4 emission


Source: Chilliard et al. (2007)

Eur. J. Lipid Sci. Technol. 109, 828-855

α-Linolenic acid

Linoleic acid

Rumenic acid

Vaccenic acid

Stearic acid

• Reduce the risk of

cardiovascular disease

• Lowering plasma

cholesterol level

• Prevent cancer

proliferation

• Decrease atherosclerosis

• Improve immune system

Modulation of PUFA biohydrogenation


Source: Khiaosa-ard et al. (2009)

J. Dairy Sci. 92, 177-188

CH: grass-clover hay (control)

TF: dried sainfoin (7.9% CT)

TH: CH + A. mearnsii extract (7.9% CT)

SH: CH + Y. schidigera extract (1.1% saponins)

Condensed tannins (CT)


Influence of tannins on biohydrogenating bacteria

Source: Vasta et al. (2010)

Appl. Environ. Microbiol. 76, 2549-2555

Containing 6.4% tannins

from quebracho powder


Inhibition of phenolics on lipase activity

Source: Van Ranst et al. (2011)

Animal 5, 512-521


Other evidences:- Jayanegara et al. (2011), Animal Production Science 51, 1127-1136- Jayanegara et al. (2012), Livestock Science 147, 104-112- Palupi et al. (online first), Journal of the Science of Food and Agriculture

Jayanegara_2011_APS_Trop biohydrogenation.pdf

Jayanegara_2012_LS_Biohydrogenation alpine.pdf

Palupi_2012_JSFA_Convent organic dairy meta.pdf


F. Treatment methods

- Wood ash: a good source of alkali; 10% solution of oak wood ash decreased the content of TP, CT and protein precipitation capacity by 66, 80 and 75% in oak leaves, respectively.

- Urea-ammoniation: 4% urea in fresh leaves. - Drying: but not effective.- Chemicals: extraction with organic solvents (30% acetone, 50%

methanol, 40% ethanol) removed ca 70% tannins from oak leaves.- Solid-state fermentation: biodegradation of tannins using white-rot

fungi.- Addition of tannin-binding polymers: PEG (polyethylene glycol)

incorporation, PVPP.


Thank you for your attention!

tannins - bogor agricultural universityanuragaja.staff.ipb.ac.id/files/2016/03/2-tannins.pdf ·...

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