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At least 1,297 records · Page 72Linked to original sources
PubMed1989

[Antibacterial actions of denture base resin on oral bacteria].

Antibacterial action of various denture base resins on thirteen species of bacteria were studied in vitro. Antibacterial effect of 5% tannin-fluoride preparation, 5% tannic acid and 5% chlorhexidine added to resins on these thirteen bacterial species were also investigated using heat-curing denture base resins. Fresh microwave-curing resin and pour-type resin each showed an antibacterial action on one bacterial strain. Fresh self-curing resins had antibacterial actions on several bacterial strains. However, after storage in water at 37 degrees C for one week, antibacterial action of microwave-curing and pour-type resin were diminished and self-curing resins partially lost their antibacterial actions. Denture base resin containing tannin-fluoride preparation or tannic acid showed an antibacterial effect on one bacterial strain. On the other hand, denture base resin containing chlorhexidine had an antibacterial action on eleven bacterial strains. However, color and mechanical properties of the drug-containing resins were not satisfactory.

Bacteria↗
PubMed2002

Nutritional quality of extruded kidney bean (Phaseolus vulgaris L. var. Pinto) and its effects on growth and skeletal muscle nitrogen fractions in rats.

The influence of extrusion cooking on the protein content, amino acid profile, and concentration of antinutritive compounds (phytic acid, condensed tannins, polyphenols, trypsin, chymotrypsin, alpha-amylase inhibitors, and hemagglutinating activity) in kidney bean seeds (Phaseolus vulgaris L. var. Pinto) was investigated. Growing male rats were fed diets based on casein containing raw or extruded kidney beans with or without methionine supplementation for 8 or 15 d. Rates of growth, food intake, and protein efficiency ratio were measured and the weight of the gastrocnemius muscle and the composition of its nitrogenous fraction was determined. Extrusion cooking reduced (P < 0.01) phytic acid, condensed tannins, and trypsin, chymotrypsin, and (alpha-amylase inhibitory activities. Furthermore, hemagglutinating activity was abolished by extrusion treatment. Protein content was not affected by this thermal treatment. Rats fed raw kidney bean lost BW rapidly and the majority died by 9 d. Pretreatment of the beans by extrusion cooking improved food intake and utilization by the rats and they gained BW. Supplementation of extruded kidney bean with methionine further enhanced (P < 0.01) food conversion efficiency and growth. However, BW gains and muscle composition still differed (P < 0.01) from those of rats fed a high-quality protein.

Animals↗
PubMed2000

Screening of selected plant extracts for in vitro inhibitory activity on HIV-1 reverse transcriptase (HIV-1 RT).

Methanolic-aqueous extracts of 70 plants were investigated for their ability to inhibit HIV-1 reverse transcriptase activity in vitro. Two thirds of the extracts screened showed more than 50% inhibition. Two extracts inhibited the enzyme completely while four exhibited more than 90% inhibition. Tannins as nonspecific HIV-1 RT inhibitors were detected and removed from the extracts. The IC50 values of the most potent extracts after the removal of tannins for the HIV-1 RT inhibition are as follows: Sambucus racemosa 0.017 mg/ml and Geranium phaeum 0.067 mg/ml. Daunomycine was chosen as a standard substance in the non-radioactive immuno assay used for screening. As a result from the future isolation and characterization of these compounds, new leading structures are expectable.

Enzyme-Linked Immunosorbent Assay↗
PubMedDate not supplied

[Preparation of tormentila tincture using ultrasound].

The procedures of preparation of ultrasound tannin extraction for preparation of Tormentillae rhizome tincture are described and the comparison was made with maceration and biomaceration methods. The contents of the isolated tannin determined volumetrically was the same, but the time of ultrasound extraction is significantly shorter and also the procedure can be performed under field conditions.

Plant Extracts↗
PubMed2005

[Influence of process methods on contents of chemical component Radix Polygoni Multiflori].

Different methods of processing Radix Polygoni Multiflori and the change of chemical components including emodin, physcion, 2,3,5,4'-stilbene glucoside, and tannin were investigated. The dried roots of polygoni were processed in different ways, such as, steamed with black bean sauce, steamed with water, stewed with black bean sauce, and stewed with black bean sauce at high pressure, for h and 36 h, respectively. The process stewing with black bean sauce was also investigated for 12, 24, 36 h, and 48 h, respectively. The results indicated that 2,3,5,4'-stilbene glucoside and total free anthraquinones varied in different processes. In the process of black bean sauce stewing, the content of 2,3,5,4'-stilbene glucoside decreased with processing time, reached 17% of original at 48 h. The content of tannin and combined and free anthraquinones also decreased with processing time. It was concluded, therefore, that the processing of Radix Polygoni Multiflori should be standardized to avoid significant variation of chemical contents.

Emodin↗
PubMed1989

[Antienzymatic activities of two Leguminosae: bean pods and bean bulls. Antiamylase activity].

Amylase inhibitory activities have been sought in the powders of Phaseolus vulgaris pods and of Vicia faba bean hulls. Unlike to the bean, Phaseolus vulgaris pod has no amylase inhibitory activity and the presence of tannin could not be determined. Contrary, Vicia faba bean hull shows an obvious amylase inhibitory activity. It contains an appreciable content of tannins which may be responsible of this activity. The quantities of amylase whose are inhibited increase in some measure with the quantities of enzyme added. They are not in direct ratio to the quantities of extract, then, inhibition may be of no competitive type.

Amylases↗
PubMed1986

[Chemical composition and evaluation of the protein quality of beans in adult humans by the short-term nitrogen balance method].

Three varieties of common beans were chemically analyzed and their protein quality was evaluated in 12 human male adult subjects by the short-term nitrogen balance method. Chemical analyses were performed for both raw and cooked grains. Cooking reduced the trypsin inhibitors in 28 to 73%, hemagglutinins, 100%, tannins as acid tannic equivalents, 9 to 72%, and 55 to 75% as catequin equivalents, and alkali-soluble nitrogen in 65%. Red and black beans contained more residual trypsin inhibitors and tannins than white beans, while the latter contained more alkali-soluble nitrogen. Although cooked colored beans had more antinutritional factors that affect protein digestibility, their protein quality was similar to that of white beans. This could be explained by the fact that the amino acid composition and/or balance of red and black beans absorbed nitrogen is better than that of white beans, so that the final nutritional value will be determined by the sum of interactions between all factors. In this study, each of the three varieties presented at least one protein quality depressor in higher concentration than the other two varieties. Therefore, the overall differences found between treatments and residual effect, were small or non existent, while significant differences (p greater than 0.05) were found between subjects and nitrogen balance periods. A level of 0.65 g of bean protein/kg/day was not enough to maintain nitrogen balance in subjects fed a diet where beans were the only protein source. According to calculations, 0.9-1.0 g of bean protein/kg/day are necessary for nitrogen balance in male adults, and 1.2-1.3 g of protein bean would be the recommendation for a normal population.

Adult↗
PubMed1986

[Peeling of sorghum by a dry method: continuous and discontinuous methods].

A study was carried out wherein two dry dehulling sorghum grain methods, the continuous and discontinuous types, were quantitatively compared in a laboratory abrasive dehulling device. Reflectance values, expressed as dehulling percentage, the percentage of kernels removed, and of kernel cracking were evaluated. Graphs of the dehulled and removed percentages as function of the contrast time for each method, revealed that the continuous process was the most efficient of both procedures. Analysis of the broken kernels indicated a similar behavior for both methods. The macrocomponent and tannin variations as dehulling advanced, as well as the reflectance values were determined with the continuous method. Findings showed that the greater proportion of tannin, fiber and ashes has been removed at the 85% extraction rate. Thus, abrasion of grains above the 65% extraction rate is not convenient, since an excessive loss of nutrients is produced without any important decrease in polyphenolic pigments and of those imparting color to the sorghum grain milling products.

Edible Grain↗
PubMed1977

[Influence of several experimental conditions on the quantity of E- and EAC-rosette forming cells in peripheral human blood].

The authors analysed the influence of some conditions of studying the rosette-formation between the human peripheral blood lymphocytes and sheep red blood cells, not loaded (a) and loaded with antibodies and a complement (b). It was shown that rosette formation depended on the temperature at which the experiment was conducted. Thus, after the incubation of a mixture of cells at 37 degrees C, and then at 4 degrees C the number of rosette-forming cells was greater than after the incubation at 4 degrees C alone. Substances used for their fixation also influenced the formation of rosettes: in the treatment of erythrocytes with formalin, tannin and glutaraldehyde, as well as introduction of the latter into the mixture of erythrocytes and leukocytes considerably increased the number of a and b (the sum of T- and B-lymphocytes exceeded 100%). Among a and b in such experimental conditions there was seen a great number of monocytes and of segmented leukocytes. Fixation of smears prepared from a mixture of cells after the incubation in formalin vapour did not lead to such increase in the number of rosette-forming cells. Apparently in case of using glutardehyde, formalin and tannin cells for the treatment of cells additional investigations are necessary with the purpose of identification of a and b as T- and B-lymphocytes.

Animals↗
PubMed1975

[The effect of heating and drugs on HL-A antigens and their reactions with cytotoxins].

In some instances the heating of lymphocytes for 2 to 3 minutes at 56 degrees C enhances HL-A antigens or makes it possible to detect these antigens by a twostage microlymphocytotoxic test on preheated lymphocytes only. Similar phenomenons are observed in some tannin (1: 40 000) or 0.1% phenol-treated lymphocytes and after the addition of these solutions during the first stage of the lymphocytotoxic test. Prolonged heating at 56 degrees C leads to nonspecific polyreactivity of lymphocytes, giving false results with all sera. For similar reasons also higher concentrations of tannin and phenol solutions were found dissatisfactory for the pretreatment of lymphocytes. The pretreatment of lymphocytes with 36-0.5% formaline induces full inhibition of specific cytotoxic reactivity of HL-A antigens and their absorption ability with regards to respective HL-A sera. The addition of formaline at 0.06-0.3% concentration during the first and second stages of the test and at the end of the second stage (or simultaneously with eosine) gives also negative results of the cytotoxic test owing to the inhibitory effect of formaline on rabbit complement and HL-A antigens.

Antigen-Antibody Reactions↗
PubMed1995

Rational approach to fractionation, isolation, and characterization of polysaccharides from the lichen Cetraria islandica.

Polysaccharides, isolated from the lichen Cetraria islandica, have antimicrobial effectiveness. For pharmaceutical applications the two glucan components lichenan and isolichenan as well as the galactomannan component are of actual interest. Especially the a-glucan isolichenan ist used as an active ingredient in cough lozenges. The conditions for the extraction of the raw material, mainly pH and temperature, have a strong influence on the yield of lichenan, isolichenan, and galactomannan, and also on the amount of tannins in the extract. Target products and also by-products give higher extraction yields with increasing extraction temperatures. Hot water extraction with subsequent fractionation of the extracted polysaccharides by multiple freezing/thawing steps and water removal applying ethanol and ether permitted the isolation of the target polysaccharides in preparative quantities. Tannins were removed by reversed phase chromatography. IR and NMR spectroscopy were used for structural characterization of lichenan and isolichenan. After optimization of the hot water extraction process no significant lower extraction and fractionation yields have been obtained compared to the established tricky DMSO extraction procedure.

Chromatography, High Pressure Liquid↗
PubMed1993

Isoproterenol/tannin-dependent R15 expression in transgenic mice is mediated by an upstream parotid control region.

Transgenic mice were used to locate the cis-acting DNA elements that are essential for tissue-specific and inducible expression of the rat proline-rich protein gene, R15. Chimeric genes with up to 10 kb of R15 5'-flanking region fused to chloramphenicol acetyltransferase (CAT) or polyomaviral large T-antigen (PyLT) reporter genes were tested. Our results demonstrate that (1) the isoproterenol/tannin-inducible, parotid-specific transgene expression requires an upstream cis-regulatory domain, namely the parotid control region, which extends from -6 to -1.7 kb of the R15 gene; (2) this parotid control region functions with a heterologous promoter and is indispensable for achieving a reproducible chromosomal position-independent transgene expression; (3) deletion of the R15 5'-flanking region up to -1.7 kb results in a pleiotropic effect on the transgene expression, which includes ectopic (nonsalivary) reporter expression and lack of inducibility by either the beta-agonist isoproterenol or dietary tannin stimulation; (4) when the -10 to -6 kb region from the R15 gene is deleted in the construct, the inducible expression in the parotid glands of the transgenic mice decreases by over 30-fold, but position-independent and tissue-specific transgene expression is retained. Moreover, the mechanism of induction by either catecholamine isoproterenol or dietary tannin appears to be through a beta 1-adrenergic receptor-mediated pathway for both normal (non-transgenic) and transgenic animals.

Animals↗
PubMed1978

[Indirect hemagglutination test at the ultrastructural level].

A study on ultra-thin sections was made of the preparations of agglutinate produced during the reaction of the immunoglobulin erythrocytic diagnostic agent with dry corpuscular Rickettsia prowazeki antigen, fluoresceine isothiocyanate labeled, and also SRBC used for the preparation of the diagnostic agent after formalinization, tannin treatment, sensitization with hyperimmune horse serum immunoglobulins and lyophilization, respectively. Formalin and tannin treatment of erythrocytes failed to be reflected on the ultrastructure of their cellular membranes; the treatment with hemosensitin was accompanied by the appearance of spheroid protrusions of the erythrocyte cytoplasmic membrane with the preservation of its three-layer structure. Specific interaction of sensitized erythrocytes with the antigen corpuscles was expressed morphologically in their apposition or connection through a gap of 20--30 nm.

Animals↗
PubMed2001

Species/variety differences in biochemical composition and nutritional value of Indian tribal legumes of the genus Canavalia.

Seeds of the Indian tribal pulses Canavalia gladiata (red and brown varieties), C. ensiformis and C. virosa were analysed for their physical characters, proximate composition, minerals, amino acid composition, dietary fibre constituents, starch fractions, fatty acid profiles and various antinutritional and/or toxic factors. Among the different species/varieties of Canavalia, the brown variety of C. gladiata was found to have the highest amount of protein (35.0%). The essential amino acid profile of total seed proteins compared favourably with the FAO/WHO reference pattern established for pre-school children, except for a deficiency of sulphur containing amino acids in both varieties of C. gladiata and C. ensiformis, whereas high concentrations of cystine and methionine were detected in C. virosa. However, tryptophan in the red variety and lysine in the brown variety of C. gladiata seemed to be the second most limiting amino acids. Generally, these Canavalia seeds appear to be a good source of potassium, phosphorus and calcium. They contain low levels of sodium. Even though the samples contained a high proportion of total starch (31.8-36.9%), the percentage of digestible starch appeared to be much higher in C. ensiformis (70.6%) and C. virosa (71.8%) than in C. gladiata. The seed lipids of all the Canavalia samples investigated had a large proportion of unsaturated fatty acids (71-78%) with oleic acid as the major one (38.6-47.4%). All samples were rich in dietary fibre (17.5-23.6%), most of which was insoluble dietary fibre. The level of the toxic amino acid, canavanine, was found to be relatively low (27-42%) in C. gladiata and C. ensiformis compared to previous literature reports for the same species. The other antinutrients such as phenolics, tannins, condensed tannins, saponins, protease inhibitors, alpha-amylase inhibitor and haemagglutinating activity were also analysed and reported here. C. ensiformis seeds exhibited a relatively high level (69.0%) of in vitro protein digestibility compared to the red (67.2%) and brown (65.4%) varieties of C. gladiata and C. virosa (62.5%).

Amino Acids↗
PubMed2000

Solid state cultivation--an efficient method to use toxic agro-industrial residues.

Studies were carried out to screen twelve strains of Lentinus edodes for their efficiency to grow on toxic agro-industrial residues of coffee industry in solid state cultivation (SSC). Based on best mycelial growth (7.57 mm/day) and biomass production (48.78 mg/plate in 12 days at 24 degrees C) in coffee husk extract medium, a strain, L. edodes LPB 02 was selected for mushroom cultivation in SSC on coffee husk (treated and untreated), coffee spent ground, and a mixed-substrate comprising coffee husk and coffee spent ground (1:1). SSC was carried out under different conditions of moisture and spawn rate. Spawn rate of 10% and moisture level of 55-60% was found suitable for all the substrates. Treatment of the coffee husk with hot water was found useful for its utilization by the fungus. Results showed that there was an increase in the protein content and decrease in the fibre content of the substrates after SSC. Fruiting bodies were obtained from the treated coffee husk, spent ground and mixed-substrate, and the biological efficiency achieved was 85.8, 88.6 and 78.4% for these substrates, respectively. However, no fruiting body was obtained with raw coffee husk was used as the substrate. Results showed that after SSC, there was a decrease of about 27, 40 and 24% in caffeine and about 18, 49 and 12% in tannin contents in the treated coffee husk, coffee spent ground and mixed substrate, respectively. No caffeine or, tannins were found in fruiting body indicating their degradation by the fungal strain.

Biodegradation, Environmental↗
PubMed2006

Nutritional chemistry of foods eaten by gorillas in Bwindi Impenetrable National Park, Uganda.

Foods eaten by gorillas (Gorilla beringei) in Bwindi Impenetrable National Park (BINP), Uganda, were analyzed for their nutrient content. The goal of the study was to assess the amounts of fiber, protein, and sugars in the foods eaten by the Bwindi gorillas, and to determine whether condensed tannins and cyanide are present in these foods. A total of 127 food plant parts representing 84 plant species eaten by two groups of Bwindi gorillas were collected, processed, and analyzed for their chemical contents. The Bwindi gorilla ate foods that contain 2-28% crude protein (CP), 21-88% neutral detergent fiber (NDF), 14-60% acid detergent fiber (ADF), 2-42% acid detergent lignin (ADL), and </=1-50% water-soluble carbohydrates (WSC) on a dry matter (DM) basis. Moisture in these foods ranged from 7% to 96%. Approximately 35% of the foods analyzed contained condensed tannins, and two foods contained cyanogenic glycosides. This is the first detailed report regarding the nutritional chemistry of gorilla foods in Bwindi, many of which are also eaten by other primates. This unique data set adds to our knowledge about the nutritional composition of foods eaten by gorillas across habitats, is useful for understanding aspects of feeding behavior, and provides valuable comparative data for optimizing the diets of gorillas ex situ.

Animal Nutritional Physiological Phenomena↗
PubMed1979

Betel quid chewing and oral cancer: experimental studies on hamsters.

Betel quid ingredients--betel nut, betel leaf, lime, catechu and tobacco--were tested separately and in various combinations for carcinogenicity, using hamster cheek pouch as the experimental site. The four modes of administration used were (1) tri-weekly painting of the cheek pouch with aqueous extracts of test materials, (2) deposition of replaceable wax pellets containing the test material, (3) gelatin capsules containing the powdered material and (4) insertion of natural material into the pouch for trauma and direct exposure. Untreated controls and standard carcinogen DMBA-treated controls were also maintained. A total of 317 young adult golden Syrian hamsters (Mesocricetus auratus) used for the experiments were killed in two age groups: 6-12 months and 13-24 months, only when signs of general debility were observed. In the untreated controls, animals were free of any malignancy. In the experimental series, various betel quid ingredient combinations under test induced both oral and gastric lesions ranging from massive atypia and precancerous lesions to frank carcinomas. Maximum lesions were observed in the groups receiving betel nut, lime and tobacco combinations and in the polyphenol fraction of betel nut containing major tannins. The mode of administration of test material resulted in distinct differences; tri-weekly paintings giving oral lesions in the range of 22-23% and gastric lesions 39-48%; the same material given either through the replaceable gelatin capsule or in natural form induced 69% oral lesions and 63 to 82% gastric lesions. Overall evaluation of the data of all the four series confirms the potent carcinogenicity of betel nut, particularly its tannin-containing polyphenolic fraction and its combination with lime and tobacco. Maximum oral lesions induced in the hamsters by continuous exposure to capsules and natural material, highlight the direct relationship of frequency of chewing in habitual chewers with oral carcinogenesis. The high incidence of gastric (forestomach) lesions invites special attention.

Animals↗
PubMedDate not supplied

Proanthocyanidins of mountain birch leaves: quantification and properties.

Proanthocyanidins (PAs; condensed tannins) are present in mountain birch leaves in soluble and cell wall-bound forms. Crude preparations of soluble PAs were isolated from birch leaves and purified by chromatography on a Sephadex LH-20 column with a yield of about 7% of leaf dry mass. Some chemical characteristics were elucidated with 13C-NMR and HPLC-ECI-MS. Birch leaf PAs were mainly delphinidin type oligo- and polymers with average molecular mass of about 3000. In order to quantify PAs, the method involving heating PA-containing materials in 1-butanol:hydrochloric acid (95:5, v/v), and spectrophotometric determination of the anthocyanidin monomers so formed was modified and optimised. Mature leaves were characterised by a relatively high content of PAs: mean values for soluble and bound PAs were 103 and 40 mg/g dry mass, respectively. In mature leaves the soluble PAs determined the total protein precipitation capacity (PPC) of extracts. In young leaves, the contribution of PAs to the total content of phenolics and the total PPC of tannins was about 20-25% only.

Anthocyanins↗