Herbivores and Plant Tannins

Bernays, Elizabeth A.; Driver, G. Cooper; Bilgener, Mahmut

doi:10.1016/s0065-2504(08)60160-9

Cited by 309 publications

(224 citation statements)

References 156 publications

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“…Chemical constituents in A. occidentale can allow its use in medicine or cosmetics and food industries (Calixto, 2000, Newman, et al 2003, Burnes et al 2001Sluis et al, 2001, Novais, et al, 2003. There is also used to get soft leather with higher durability, cleanse impurities from gasoline, food & beverage manufacturing, etc (Bernays et al, 1989). Harbone et al, 1991;Schreiber et al, 1993).…”

Section: Introductionmentioning

confidence: 99%

Influence of gamma radiation on the antimicrobial activity of crude extracts of Anacardium occidentale L., Anacardiaceae, rich in tannins

Santos¹,

Silva²,

Silva³

et al. 2011

Rev. bras. farmacogn.

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Anacardium occidentale L. Anacardiaceae, known as cashew, commonly found in northeastern of Brazil, has high levels of secondary metabolites, particularly tannins, used as raw material for herbal medicines. An effi cient alternative to decontaminate plant products is the total sterilization or reduction of the initial microbial count, the process of gamma irradiation with 60 Co. The objective of this study was to analyze the antimicrobial activity of crude extracts of bark and leaves of A. occidentale, based on the quantifi cation of total phenols and tannins, before and after exposure to gamma radiation from 60 Co. The extracts were obtained in the laboratory by cold maceration in ethanol, fi ltered and dryness. They were divided into non-irradiated control group (0 kGy) and irradiated: groups exposed to gamma radiation at doses of 5, 7.5 and 10 kGy. The total phenols was obtained by the Folin-Ciocalteau method and tannins, by the precipitation of casein. The antimicrobial potential activities of these extracts were also evaluated. The results showed that gamma radiation doses employed in this study did not infl uence statistically the percentage of total phenols and tannins in the bark extracts, at levels ranging from 5.73±0.14 and 5.20±0.14, respectively. The levels of metabolites in the leaves were statistically (p<0.05) infl uenced by radiation, observed average total phenols between 3.13±0.04 (0 kGy) and 3.50±0.08 (10 kGy), and tannin between 2.47±0.06 (0 kGy) and 2.93±0.04 (10 kGy). The extracts of bark and leaves were active against Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis, Enterococcus faecalis, Mycobacterium smegmatis, Candida albicans. Gamma radiation caused an increase in antimicrobial activity of extracts against Staphylococcus aureus (Gram positive), with average inhibition zones for shells: 14.33±058 (0 kGy) and 22.33±0.58 (10 kGy), and leaves: 11.33±0.58 (0 kGy) and 19.00±1.00 (10 kGy). Exposure to radiation caused changes in physical and chemical constituents of phenolic extracts of leaves of cashew, increasing levels of tannins.

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Section: Introductionmentioning

confidence: 99%

Influence of gamma radiation on the antimicrobial activity of crude extracts of Anacardium occidentale L., Anacardiaceae, rich in tannins

Santos¹,

Silva²,

Silva³

et al. 2011

Rev. bras. farmacogn.

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“…Phlorotannins may also possess primary metabolic functions, for example contributing to cell wall structure and reproduction, which could lead to misinterpretation of data testing ecological theories of chemical defense (Arnold & Targett 2003). Similar difficulties have restricted generalizations about the function of terrestrial plant tannins, which were originally proposed to act as digestibility reducers that few herbivores could tolerate (Feeny 1976), but which were later found to occasionally act as toxins and, in other cases, to be tolerated or even to stimulate some grazers (reviewed in Bernays et al 1989). …”

Section: Introductionmentioning

confidence: 99%

Ambiguous role of phlorotannins as chemical defenses in the brown alga Fucus vesiculosus

Kubanek

Lester²,

Fenical³

et al. 2004

Mar. Ecol. Prog. Ser.

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Brown seaweeds (Fucales) produce phlorotannins that are often considered chemical defenses against herbivores. The many correlative and fewer direct tests conducted have shown effects of phlorotannins on herbivore feeding behavior to be variable. In an attempt to clarify the roles of phlorotannins versus other metabolites in defending brown algae, we conducted bioassay-guided fractionation of herbivore-deterrent extracts from the commonly studied brown alga Fucus vesiculosus. Feeding by the amphipods Ampithoe valida and A. longimana and the sea urchin Arbacia punctulata was suppressed by crude and water-soluble extracts of F. vesiculosus, but this deterrence was lost following storage or fractionation of the active, water-soluble extract. Phlorotannins in these extracts did not decompose in parallel with the loss of feeding deterrence. F. vesiculosus phlorotannins were fed to herbivores at 3 to 12 × the isolated yield (or 4.2 to 16.8% of plant dry mass). No herbivore was deterred from feeding by concentrations of 3 or 6 ×, but A. valida (the only test herbivore that readily consumes F. vesiculosus in the field) was deterred at 12 × isolated yield. When juvenile A. valida were raised on an artificial diet containing F. vesiculosus phlorotannins at 3 × isolated yield, the phlorotannin-rich diet significantly enhanced, rather than reduced, amphipod survivorship and growth relative to an equivalent diet without phlorotannins. Females ovulated only on the phlorotannin-rich diet. Compounds other than phlorotannins appear to defend the F. vesiculosus populations we investigated, but we were unable to identify these unstable compounds.

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“…Animals that regularly browse CT-containing plants have developed resistance to tannins, at least partly through the presence of tannin-resistant ruminal microorganisms (Bernays et al, 1989). Tannins have also been reported to induce changes in the morphology of several species of ruminal bacteria (Jones et al, 1994 ;McAllister et al, 1994).…”

Section: Introductionmentioning

confidence: 99%

Effect of hydrolysable and condensed tannins on growth, morphology and metabolism of Streptococcus gallolyticus (S. caprinus) and Streptococcus bovis

O’Donovan

Brooker

2001

Microbiology

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Streptococcus gallolyticus (S. caprinus) was resistant in vitro to at least 7 % (w/v) tannic acid and 4 % (w/v) acacia condensed tannin, levels 10-fold greater than those tolerated by S. bovis. Growth of S. gallolyticus in liquid medium was characterized by a lag period which increased, and a growth rate which decreased, with increasing tannin concentration. S. gallolyticus was also more tolerant to the presence of simple phenolic acid monomers than was S. bovis, but the lag period was still concentration dependent. Gallate decarboxylase activity in S. gallolyticus was elevated in the presence of tannic acid or gallic acid but not with other phenolic acids. Scanning electron microscopic analysis showed that both the size and shape of S. gallolyticus and S. bovis changed in response to tannin but only S. gallolyticus was surrounded by an extracellular polysaccharide matrix which accumulated in a tannin-concentration-dependent fashion. Washing of the cells to remove extracellular polysaccharide increased the lag period of S. gallolyticus in the presence of 1 % (w/v) tannic acid from 4 h to 6 h. In contrast, increasing extracellular polysaccharide synthesis in S. bovis did not increase its tolerance to tannic acid. These data demonstrate that S. gallolyticus has developed a number of mechanisms to reduce the potential effect of tannins on cell growth, and that these mechanisms provide the organism with a selective advantage over S. bovis when grown in the presence of tannins.

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Herbivores and Plant Tannins

Cited by 309 publications

References 156 publications

Influence of gamma radiation on the antimicrobial activity of crude extracts of Anacardium occidentale L., Anacardiaceae, rich in tannins

Influence of gamma radiation on the antimicrobial activity of crude extracts of Anacardium occidentale L., Anacardiaceae, rich in tannins

Ambiguous role of phlorotannins as chemical defenses in the brown alga Fucus vesiculosus

Effect of hydrolysable and condensed tannins on growth, morphology and metabolism of Streptococcus gallolyticus (S. caprinus) and Streptococcus bovis

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