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Summary The types and quantities of defense compounds found in plants occupying ecologically distinct habitats have received much theoretical and little empirical attention. Here we characterize the leaf phenolic chemistry of eight species in two genera of tropical rainforest shrubs; four species in each genus are typical of disturbed sites, and four are typical of mature forest understory. Two Miconia species growing in light gaps had significantly higher leaf tannin and total phenolic contents than congenors growing in the primary forest; this pattern was not found among the gap- and forest-adapted Piper species. Tannin patterns were not mirrored by leaf cinnamic acids. These results indicate that plant phylogeny must be considered when predicting plant defense investment. 相似文献
2.
We observed the foraging behavior of orangutans in Central Indonesian Borneo during October, November, and December 1980,
and analyzed food and nonfood items for water content, neutral detergent fiber, crude protein, available crude protein, and
protein:fiber ratio and the presence of alkaloids and tannins. The diet of the orangutan during this season was unusual because
it consisted predominantly of seeds and unripe, rather than ripe, fruits. Also, the major diet item, the seeds ofIrvingia malayana, had been ignored in previous years when it had fruited. In leaves, protein content was more closely associated with food
choice than either neutral detergent fiber or the protein:fiber ratio. Flowers had the highest protein content and protein:fiber
ratio of any food item. Tannins were found in most food items, but the presence of alkaloids was found in only one. 相似文献
3.
Summary Tannin, cell wall, and nitrogen composition of green foliage and needle litter of similar-aged Douglas-fir (Pseudotsuga menziesii Mirb. Franco) from two stands differing in density and crown closure were compared. Trees in the closed-canopy stand had a lower basal area growth rate than those in the open-canopy stand. Stands did not differ in wood basal area/ha or forest floor C/N ratios, but the closed-canopy stand had a significantly larger accumulation of forest floor biomass and significantly higher levels of field-extractable nitrogen and nitrogen mineralization rates. Green foliage from trees in the closed-canopy stand had significantly lower nitrogen, astringency, and lignin contents, but higher cellulose concentration than trees in the open-canopy stand. These trends, inconsistent with the inverse relationship often observed between nitrogen and polyphenol contents of foliage, may result from differences in relative resource availability in the two stands. In contrast to green foliage, needle litter from the two stands had comparable contents of nitrogen, cellulose, and lignin, but astringency was significantly higher in litter from the closed-canopy stand. It is suggested that, within the constraints imposed by site conditions, evergreens may alter the tannin composition of senescing foliage, potentially affecting herbivory and decomposition differently. 相似文献
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Why are grape/fresh wine anthocyanins so simple and why is it that red wine color lasts so long? 总被引:1,自引:0,他引:1
Vitis vinifera red berries are characterized by anthocyanins whose chemical structures are among the simplest encountered in higher plants. On the contrary, many plants, including orchids, petunias, red cabbage, elderberries, potatoes for instance, have developed very complicated anthocyanins featuring side-chains at the available positions of the aglycone skeleton. Such pigments were shown to possess bio-physico-chemical properties not to be seen with the grape common anthocyanins. Among beverages (water, tea, beer, wine, coffee, juices, milk), red wine is the only one whose organoleptic properties improve with time and this is called ageing. The grape/fresh red wine pigments, after a few months, disappear from the wine giving birth to new pigments resulting from the wine spontaneous chemistry allowing it to remain red for many years. What are the wine pigments and why are they so stable is the purpose of this mini-review. The structural simplicity of grape anthocyanins and the long lasting colour of red wine is another French paradox; we call it French paradox II. 相似文献
6.
通过饲喂自然种子及人工饲料块等单宁和皂苷含量不同的食物,研究了食物中单宁或皂苷水平对小白鼠(Mus musculus domesticus)食物选择的影响,以及取食经历在其食物选择中的作用。结果表明,(1)无论有无取食经历,小白鼠均优先取食次生物质含量低的锥栗(Castanea henryi)或花生(Arachis hypogaea),而很少取食单宁含量高的栓皮栎(Quercus variabilis)或皂苷含量高的油茶(Camelia oleifera);(2)小白鼠的取食经历能增强其对种子中单宁或皂苷水平的识别,从而减少其摄入;(3)小白鼠的食物摄入量随单宁或皂苷含量的增加而显著降低。本研究说明单宁或皂苷均可显著影响动物的食物选择,且取食经历能增强动物对食物的识别能力。 相似文献
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Deer can have severe effects on plant communities, which in turn can affect insect communities. We studied the effects of
Key deer herbivory on the incidence of insect herbivores that occur within deer habitats in the lower Florida Keys, within
the National Key Deer Refuge (NKDR). We analyzed plant chemistry (tannins, nitrogen) and surveyed for the occurrence of insects
(above the browse tier) among plant species that were either deer-preferred or less-preferred. Results indicated higher levels
of foliar tannins on islands with fewer Key deer and larger amounts of foliar nitrogen on islands with a high density of Key
deer. Consequently, leaf miners were significantly more abundant on islands with high deer density, irrespective of deer-preference
of plant species. On islands with a high deer density, incidence of leaves damaged by chewing insects was lower on preferred
plant species but greater on less-preferred species than on islands with fewer deer. No apparent patterns were evident in
the distribution of leaf gallers among plant species or islands with different deer density. Our results imply that plant
nutrition levels—either preexisting or indirectly affected by deer deposition—are more important than plant defenses in determining
the distribution of insect herbivores in the NKDR. Although high densities of the endangered Key deer have negative effects
on some plant species in the NKDR, it seems Key deer might have an indirect positive influence on insect incidence primarily
above the browse tier. Further research is warranted to enable fuller understanding of the interactions between Key deer and
the insect community. 相似文献
9.
Tannins occur commonly in the wastewaters from forestry, plant medicine, paper and leather industries. The treatment of this
kind of wastewaters, including settling and biodegradation, is usually difficult because tannins are highly soluble in water
and would inhibit the growth of microorganisms in activated sludge. The objective of this study is to investigate biodegradability
of tannin-containing wastewaters, so as to characterize the pollution properties of such wastewaters and provide a reference
for their biological treatment in wastewater treatment plants. The research was typified by using the wastewater collected
from vegetable tanning process in leather industry. A model was developed to describe the activated sludge process, and the
biodegradation kinetics of vegetable tanning wastewater (VET wastewater) was studied. It was found that the biodegradability
of tannin-containing wastewater varies heavily with the content of tannins in wastewater. The biodegradation of VET wastewater
with tannin content around 4,900 mg/l occurred inefficiently due to the inhibition of tannins to the activated sludge process,
and only 34.7% of biodegradation extent was reached in 14 days of incubation. The optimal biodegradability of VET wastewater
was observed when its tannin content was diluted to 490 mg/l, where the COD and tannin removals reached 51.3% and 45.1% respectively
in 6 days. Hence, it is suggested that a proper control of tannin content is necessary to achieve an effective biodegradation
of tannin-containing wastewaters in wastewater treatment plants. 相似文献
10.
Natalia Gutierrez C. M. Avila C. Rodriguez-Suarez M. T. Moreno A. M. Torres 《Molecular breeding : new strategies in plant improvement》2007,19(4):305-314
Faba beans are inexpensive, nutrient-dense sources of plant protein, but anti-nutritional factors such as condensed tannins
reduce the biological value of their protein. Two recessive genes, zt-1 and zt-2, control the absence of tannins in faba bean seeds and also determine a white flower character on the plant. However, crosses
between them produce coloured F1 plants with tannins that contaminate the crop. Therefore, it is important to identify the gene present in all tannin-free
cultivars and gene bank accessions to enable breeders to choose appropriate genitors for their crosses. The aim of this study
was the identification of markers linked to zt-1, one of the genes governing free tannin content in faba bean. A segregating F2 population derived from the cross between the coloured flower and high tannin content genotype Vf6 and a zt-1 line was developed and characterized phenotypically. Bulked Segregant Analysis (BSA) was used to identify Random Amplified
Polymorphic DNA (RAPD) markers linked to the zt-1 gene. Four RAPD loci (OPC5551, OPG15600, OPG111171 and OPAF20776) showed polymorphism between the contrasting bulks. The markers were sequenced to develop specific Sequence Characterised
Amplified Regions (SCARs). Amplification of SCC5551 produced a single product which was only observed in the white flowered and zero tannin content genotypes, whereas SCAR
SCG111171only produced a band in F2 plants with coloured flower and high tannin content. SCARs SCC5551 and SCG111171 were tested for their applicability for routine screening in 37 faba bean genotypes differing in flower colour and tannin
content. SCC5551, allowed the prediction of the zt-1 genotypes with a 95% of accuracy, underscoring the potential of this SCAR marker as a cost-effective tool for MAS in large
faba bean breeding populations. 相似文献