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At least 1,495 records · Page 83Linked to original sources
PubMed1995

Effect of processing on nutrient composition and anti-nutritive substances of African locust bean (Parkia filicoidea) and baobab seed (Adansonia digitata).

The effects of various processing techniques on nutrient composition and anti-nutritional factors in baobab seeds (Adansonia digitata L.) and locust beans (Parkia filicoidea L.) were investigated. The methods used for processing include boiling in water, acid or alkali and fermentation. Using the water treated samples as controls, there were slight decreases in protein and carbohydrate contents of the fermented and alkali-treated meals. However, an increase in extractable oil content was observed in acid, alkali and fermented samples. The alkali treatment appeared to be the most effective method for reducing trypsin inhibitor and tannin contents and has the additional advantage of improving the protein digestibility.

Fabaceae↗
PubMed1993

Chemical composition and nutritional potential of the tribal pulse (Bauhinia malabarica Roxb).

Proximate and mineral composition, seed protein fractions, amino acid composition, fatty acid profiles and antinutritional factors were analysed for the seeds of the tribal pulse, Bauhinia malabarica. The seeds contained higher amount of crude lipid when compared with most of the domesticated pulses. The seeds were rich in minerals like Ca, Mg and Fe. Glutelins (45%) constituted the major seed protein fraction followed by globulins which accounted for about 34%. Cystine and methionine were found to be the limiting essential amino acids; whereas tyrosine and phenylalanine content were fairly high when compared with WHO requirement pattern. The unsaturated fatty acids, oleic acid and linoleic acid, were predominant in seed lipids. Presence of antinutritional substances like total free phenols, tannins, L-DOPA and haemagglutinating activity also were analysed/assayed.

Amino Acids↗
PubMed1994

Chemical, nutritional and technological characteristics of buckwheat and non-prolamine buckwheat flours in comparison of wheat flour.

Chemical, nutritional, and technological characteristics of buckwheat and non-prolamine buckwheat flours in comparison to wheat for celiac patients use have been studied. The results suggested the following conclusions: the 56.5% extraction value for flour obtention is considered good; the buckwheat flour presents methionine and cystine as first limiting amino acids followed by threonine as the second limiting amino acid; the buckwheat flour presents higher content of lysine amino acids than the wheat flour; the buckwheat flour is superior to the wheat flour regarding iron, copper, and magnesium minerals; the buckwheat flour does not present haemagglutinin activity and the tannin content is negligible. Rheological assays indicate that the buckwheat flour does not contain gluten.

Brazil↗
PubMed1994

Chemical and nutritional evaluation of two germplasms of the tribal pulse, Bauhinia racemosa Lamk.

Two germplasms of the tribal pulse, Bauhinia racemosa Lamk. viz., Ayyanarkoil Forest and Mundanthurai Wildlife Sanctuary, were analysed for proximate composition, total (true) seed proteins, seed protein fractions, amino acid composition, fatty acids, minerals and antinutritional factors. Crude proteins, crude lipids, ash and nitrogen free extractives constituted 19.84%, 9.52%, 3.31% and 60.65%, respectively in Ayyanarkoil Forest germplasm; whereas, in Mundanthurai Wildlife Sanctuary germplasm they constituted 19.31%, 8.94%, 3.81% and 61.30%, respectively. The caloric values were found to be 407.64 KCal (Ayyanarkoil Forest) and 402.90 KCal (Mundanthurai Wildlife Sanctuary) germplasms. Essential amino acids like isoleucine, tyrosine, phenylalanine and lysine were found to be high in the seed proteins of both the germplasms. The fatty acids, palmitic, oleic and linoleic acids, were found to be relatively higher in the seed lipids of both the germplasms. Both the germplasms seemed to be a rich source of calcium, potassium, magnesium, zinc, manganese and iron. Antinutritional substances like total free phenols, tannins, L-DOPA and phytohaemagglutinating activity also were investigated.

Amino Acids↗
PubMed1994

Nutritional evaluation of spent grains from sorghum malts and maize grit.

Potential use of the high protein by-product of beer production from 77% sorghum malt and 23% maize grit was investigated. Red sorghum spent grains (RSSG) and white sorghum spent grains (WSSG) contained 23.4 and 19.3% crude protein (CP), 54 and 43% dietary fiber (NDF), 1.44 and 0.78% ash, 4.5 and 3.2% hexane extract and tannin content of 7.5 and 1.0 mg/g catechin equivalent respectively. Magnesium was the most abundant mineral in both RSSG and WSSG--185 and 140 mg/kg, respectively. Calcium, zinc, iron and copper were generally low. Both samples contained cadmium 1.12 (WSSG), 1.19 (RSSG) and lead at 1.38 mg/kg. Lysine was the limiting amino acid (chemical score 0.55) in both samples. Other essential amino acids were adequate or surplus. Stearic acid was the predominant fatty acid with varying levels of lauric, myristic, palmitic, and oleic acids in both samples. Feed intake and weight gain were highest in rats fed 26.3% WSSG (contributing 50% of the diet protein) but protein efficiency ratio (PER) and net protein retention (NPR) were highest in diets where spent grains contributed just 25% of the diet protein. True digestibility of diets decreased as dietary fiber content increased such that animals on diets containing 100% spent grain protein (above 20% NDF) lost weight.

Amino Acids↗
PubMed1996

Chemical composition and nutritional potential of yam bean seeds (Pachyrhizus erosus L. urban).

Pachyrhizus erosus seeds were analysed for proximate composition, minerals, protein fractions, antinutritional factors, and rotenoids. The seeds showed a high content of proteins, lipids, Fe and Ca, in comparison to other legumes. Glutelins constitute the highest protein fraction, followed by globulins. Antinutritional substances detected as tannins, hemagglutinating activity and trypsin inhibitory activity, were in low concentrations. Seeds were also processed to obtain a flour which showed proper characteristics, good in vitro digestibility, significant rotenoid reduction level and amino acid composition rich in essential amino acids, except methionine.

Amino Acids↗
PubMed1987

Stabilisation of collagen by betel nut polyphenols as a mechanism in oral submucous fibrosis.

Treatment of reconstituted collagen fibrils and pieces of rat dermis with the crude extract, purified tannins or (+)-catechin from betel nut (Areca catechu) increases their resistance to both human and bacterial collagenases in a concentration-dependent manner. These tanning agents may stabilise collagen in vivo following damage to the oral epithelium, and promote the sub-epithelial fibrosis which occurs in betel nut chewers.

Animals↗
PubMed1992

The biochemical composition and nutritional potential of the tribal pulse, Mucuna monosperma DC. ex Wight.

Two germplasms of the tribal pulse, Mucuna monosperma Dc. ex Wight, viz., Thirunelly Reserve Forest, Wynaad District (Kerala) and Siruvani Reserve Forest, Coimbatore District (Tamilnadu), were analysed for proximate composition, total (true) seed proteins, seed protein fractionation, amino acid composition, fatty acids, minerals and anti-nutritional factors. Crude proteins, crude lipids, ash and nitrogen free extractives constituted 23.10%, 4.36%, 3.80%, 61.74%, respectively, in Tamilnadu germplasm; whereas, in Kerala germplasm they constituted 20.13%, 8.99%, 3.60% and 61.69%, respectively. The calorific values of 100 g dry matter of seed material are 408.19 KCal (Kerala) and 378.60 KCal (Tamilnadu) germplasms. Essential amino acids like methionine, cystine, threonine and valine were found to be limiting in the seed proteins of both the germplasms. The fatty acids like lauric acid and palmitic acid are found to be common in both the germplasm seed samples, while linoleic and oleic acids in Kerala germplasm and stearic acid in Tamilnadu germplasm are present. The Tamilnadu germplasm seems to be a rich source of sodium, magnesium, zinc, manganese, copper and iron; whereas the Kerala germplasm seems to be a rich source of phosphorus. Antinutritional substances like total free phenols, tannins, L-DOPA, trypsin inhibitor activity and phytohaemagglutinating activity also were investigated.

Amino Acids↗
PubMed1991

The biochemical composition and nutritional potential of the tribal pulse, Mucuna gigantea (Willd) DC.

Seeds of the tribal pulse, Mucuna gigantea, were analysed for proximate composition, total (true) seed proteins, seed protein fractionation, amino acid composition, minerals and antinutritional factors. Crude proteins, crude lipids, ash and nitrogen free extractives constituted 30.62%, 9.03%, 5.99% and 42.79%, respectively. The calorific values of 100 g dry matter of seed material is 374.91 kCal. The essential amino acids, leucine + isoleucine, are present in relatively large quantities. The seeds are rich in minerals like K, Ca, Mg and Fe. Antinutritional substances like total free phenols and tannins, trypsin inhibitor activity and haemagglutinating activity also were investigated.

Albumins↗
PubMed1997

Physicochemical characteristics of five date fruit cultivars grown in the United Arab Emirates.

The physical measurements and chemical analyses of date fruits of five cultivars grown in the United Arab Emirates were measured in this study. Due to differences in seed weight, the flesh accounted for 83-92% of the total fruit. At the tamr stage, the absence of sucrose and the presence of higher concentrations of reducing sugars, especially fructose and glucose, characterized these cultivars as the soft type. On maturation from the kimri to the tamr stage, the sugar content had increased, but other constituents like moisture, crude protein, crude fat, ash, crude fiber, tannins, and pectin had decreased.

Carbohydrates↗
PubMed1997

Complement activating agents in allergenic extracts.

OBJECTIVE: Extracts of environmental allergens, moulds and plant pollens are known to consume haemolytic complement (huC) in human serum in vitro through the antibody-independent engagement of the first component C1 of the classical pathway. The present work was undertaken to establish the nature and characteristics of the complement activating agents in allergenic extracts and to probe their relationship with the IgE-binding allergens. MATERIALS AND METHODS: A large series of different > 10 kDa allergenic products was investigated for their capacity to consume haemolytic complement in the sera of allergic patients with specific anti-allergen IgE antibodies, as well as in normal control sera. UV-spectroscopy was used for categorizing the non-protein components in the extracts. RESULTS: The experiments confirmed that huC is consumed in an antibody-independent fashion and in a qualitatively similar, but quantitatively distinct manner. The ratio of the complement activating potencies among the different allergenic preparations thereby remained constant and independent of the serum source, while an overt relationship with specific IgE-antibodies could not be established. UV-spectroscopy of the allergenic preparations revealed the presence of chemical decomposition products in nearly every extract and roughly in proportion to the complement activating potencies. CONCLUSION: The data support the idea that huC-activation by traditional allergenic extracts is mainly due to by-stander degradation products of the melanoidin (Maillard) or tannin type, which may or may not occur in physical association with the IgE-binding protein allergens.

Allergens↗
PubMed2002

Development of CAPS markers based on three key genes of the phenylpropanoid pathway in tea, Camellia sinensis (L.) O. Kuntze, and differentiation between assamica and sinensis varieties.

The genetic diversity of tea, Camellia sinensis (L.) O. Kuntze, including the two main cultivated sinensis and assamica varieties, was investigated based on PCR-RFLP analysis of PAL, CHS2 and DFR, three key genes involved in catechin and tannin synthesis and directly responsible for tea taste and quality. Polymorphisms were of two types: amplicon length polymorphism (ALP) due to the presence of indels in two introns of PAL and DFR, and point mutations detected after restriction of amplified fragments with appropriate enzymes. A progeny test showed that all markers segregated in a Mendelian fashion and that polymorphisms were exclusively co-dominant. CHS2, which belongs to a multi-gene family, allowed for greater variation than the single-copy PAL gene. Based on Nei's gene diversity index, var. sinensis was revealed to be more variable than var. assamica, and that a higher proportion of overall diversity resided within varieties as compared to between varieties. Even though no specific DNA profile was found for either tea varieties following any single PCR-RFLP analysis, a factorial correspondence analysis carried out on all genotypes and markers separated the tea samples into two distinct groups according to their varietal status. This reflects the large difference between var. sinensis and var. assamica in their polyphenolic profiles. The STS-based markers developed in this study will be very useful in future mapping, population genetics and fingerprinting studies of this important crop species and other Camellia species, as the primers have also proven successful in the three other subgenera of this genus.

Acyltransferases↗
PubMed2005

Purification and characterization of tannase from Paecilomyces variotii: hydrolysis of tannic acid using immobilized tannase.

An extracellular tannase (tannin acyl hydrolase) was isolated from Paecilomyces variotii and purified from cell-free culture filtrate using ammonium sulfate precipitation followed by ion exchange and gel filtration chromatography. Fractional precipitation of the culture filtrate with ammonium sulfate yielded 78.7% with 13.6-folds purification, and diethylaminoethyl-cellulose column chromatography and gel filtration showed 19.4-folds and 30.5-folds purifications, respectively. Molecular mass of tannase was found 149.8 kDa through native polyacrylamide gel electrophoresis (PAGE) analysis. Sodium dodecyl sulphate-PAGE revealed that the purified tannase was a monomeric enzyme with a molecular mass of 45 kDa. Temperature of 30 to 50 degrees C and pH of 5.0 to 7.0 were optimum for tannase activity and stability. Tannase immobilized on alginate beads could hydrolyze tannic acid even after extensive reuse and retained about 85% of the initial activity. Thin layer chromatography, high performance liquid chromatography, and (1)H-nuclear magnetic resonance spectral analysis confirmed that gallic acid was formed as a byproduct during hydrolysis of tannic acid.

Carboxylic Ester Hydrolases↗
PubMed2003

The resource economics of chemical and structural defenses across nitrogen supply gradients.

In order to better understand the role of nutrient supplies in determining the prevalence of plant defense types, we investigated the theoretical relationships between ecosystem N supply and the net C gain of shoots that were undefended or defended in one of three ways: (1) by N-free chemical compounds, (2) by N-containing chemical compounds, or (3) by structural defenses. By extending economic models of shoot resource balance to include the relative value of C and N, depreciation, and amortization, we were able to show that the relative net C gain of the three defense types were similar to changes in their generally understood abundance along an N supply gradient. At low N supply, the additional C acquired when investing C in defense is much higher than investing N in defenses. Only at high N supply is it better to invest large quantities of N in defense rather than additional photosynthesis. In a sensitivity analysis, net C gain of shoots was most sensitive to factors that affect the relative value of C and N and the rate of herbivory. Although there is support for the relative value of C and N influencing defense strategies, more research is necessary to understand why tannins are not more prevalent at high N supply and why moderate amounts of N-based defenses are not used at low N supply.

Adaptation, Physiological↗
PubMed2004

A comparison of morphological and chemical fruit traits between two sites with different frugivore assemblages.

Large-scale comparisons might reveal matching between fruit traits and frugivore assemblages that might be cryptic on a local scale. Therefore, we compared morphological (colour, size, husk thickness) and chemical fruit traits (protein, nitrogen, sugar, lipid, tannin and fibre content) between Malagasy and South African tree communities with different frugivore communities. In Madagascar, where lemurs are important seed dispersers, we found more tree species with fruit colour classified as "primate fruits". In contrast, in South Africa we found more tree species with fruits classified as "bird coloured". This correlated with the greater importance of frugivorous birds in South Africa vs. Madagascar. Additionally, we found higher sugar concentrations in fruits from the South African tree community and higher fibre content in fruits from the Malagasy tree community. However, fibre content could be related to differences in abiotic conditions between the two study sites. This suggests that fruit colour more than other morphological and chemical fruit traits, reflects food selection by the different frugivore assemblages of those two sites.

Animals↗
PubMed2004

Perfect is best: low leaf fluctuating asymmetry reduces herbivory by leaf miners.

Fluctuating asymmetry (FA) represents small, random variation from symmetry and can be used as an indicator of plant susceptibility to herbivory. We investigated the effects of FA of two oak species, Quercus laevis and Q. geminata, and the responses of three herbivore guilds: leaf miners, gallers, and chewers. To examine differences in FA and herbivory between individuals, 40 leaves from each tree were collected, and FA indices were calculated. To examine differences in FA and herbivory within-individuals, we sampled pairs of mined and unmined leaves for asymmetry measurements. Differences in growth of leaf miners between leaf types were determined by tracing 50 mines of each species on symmetric leaves and asymmetric leaves. Asymmetric leaves contained significantly lower concentrations of tannins and higher concentrations of nitrogen than symmetric leaves for both plant species. Both frequency of asymmetric leaves on plants and levels of asymmetry positively influenced the abundance of Brachys, Stilbosis and other leaf miners, but no significant relationship between asymmetry and herbivory was observed for Acrocercops. Brachys and Stilbosis mines were smaller on asymmetric leaves, but differences in mine survivorship between symmetric and asymmetric leaves were observed only for Stilbosis mines. This study indicated that leaf miners might use leaf FA as a cue to plant quality, although differential survivorship among leaf types was not observed for all species studied. Reasons for the different results between guilds are discussed.

Animals↗
PubMed2002

Epidermal and hypodermal characteristics in North American Cactoideae (Cactaceae).

Dermal and hypodermal anatomical features of 70 species representing 21 genera of North American Cactoideae were studied. Results show that all species examined have parallelocytic stomata and anticlinal wall surface varies from straight to undulate. Cuticle thickness is mostly narrow (1-10 microm) contrary to the general opinion that cuticle is thick in most cacti; however, few species such as Ariocarpus fissuratus and several species of Pachycereus show a distinctive thick cuticle. More than 80% of the species studied have a single-layered epidermis. Papillae occur in eight species belonging to four genera. Notable papillae are a feature shared by all members of Peniocereus subg. Peniocereus. Other species show a bullate surface produced by irregular patches of secondary epidermal cell divisions. Commonly, the hypodermis is composed of more than two cell layers with distinctive collenchymatous walls as reported in many South American species. Silica bodies, prismatic crystals, druses, sphaerocrystals, and tannins are the most common cellular inclusions that distinguish several genera and appear to have taxonomic value. However, a more thorough search in species of Cephalocereus, Coryphantha, Echinocereus, Mammillaria, Neobuxbaumia, Pilosocereus, and Turbinicarpus is needed to support the previous assertion.

Cactaceae↗
PubMed2005

The role of taste in food selection by African apes: implications for niche separation and overlap in tropical forests.

Ripe fruit eating shapes the behavior of most of the apes. Gorillas (Gorilla gorilla) and chimpanzees (Pan troglodytes) are very different sizes and, consequently, have been traditionally viewed as ecologically distinct, but few studies have explored the behavioral and physiological foundations of their diets. Debate continues on the extent that large-bodied gorillas may be less selective and more opportunistic fruit eaters than chimpanzees. Taste responses have been predicted to relate to body size and digestive strategies. This study employs laboratory research on taste perception and discrimination among captive zoo-housed chimpanzees and relates it to previous work on gorillas to better characterize diets and niche separation among these apes. During the captive trials, differences were recorded in consumption patterns of water and varying concentrations of dilute aqueous fructose (sweet) and tannic acid solutions (astringent), compounds commonly found in wild foods. The chimpanzees exhibited similar preference thresholds for fructose (50 mM) to other primates studied. They exhibited slightly lower inhibition thresholds for tannic acid solutions than gorillas, but higher than smaller primates studied to date. These preliminary findings suggest that tannin tolerance may well be mediated by body size, though possible species differences in salivary proteins or other sensory differences remain to be explored. This research furthers our efforts to understand the roles of body size and physiological adaptations in shaping diet and niche separation of chimpanzees and gorillas.

Animals↗