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31.
Epidemiological studies support the belief that whole grains are protective against several chronic diseases. The health benefits of whole grains are attributed in part to their unique phytochemical composition. Major phytochemicals in grains include various classes of phenolic compounds, flavonoids and coumarin derivatives, etc. Phenolic compounds present in grains possess antioxidant properties that are associated with the health benefits of grains and grain products. Sorghum is one of the main staple cereal grains in hot dry tropics and ranks fifth among cereal crops in the world. Although sorghum is rich in phenolics and tannins which are proven anticancer and cardioprotective constituents, human consumption of sorghum is limited. To our knowledge, there is limited literature on the profile of antioxidant phytochemicals in the local white variety of sorghum. Hence, the objective of this study was to investigate the antioxidant property of white sorghum flour extracts in vitro and also to identify the fractions responsible for the antioxidant activity. In the present study, we analyzed the antioxidative properties of various extracts (water, 60% methanol, 60% ethanol, and 60% t-butanol) of white sorghum flour employing the 1,1-diphenyl-2-picrylhydrazyl (DPPH) model system. Phenolics, antiradical and antioxidant activities were also examined in chromatographic sub-fractions of the soxhlet methanolic extract. Our results indicated that the various extracts exhibited significant antioxidant activity that did not correlate with the phenolic content. Further, two sub-fractions eluted with methanol and acetone/methanol were found to possess strong antioxidant activity in two assay systems. Our results suggest that a diet rich in sorghum may be useful in combating diseases in which free radical production plays a key role.  相似文献   
32.
Digestive enzyme profile is a good indicator of the nutritional and health status of the fish. The present investigation aims to evaluate the effect of exogenous bath treatment of hormones, cortisol and triiodothyronine, on the digestive enzyme activities and growth of carp Catla catla (Ham.) during ontogenic development. Catla larvae (4 days old) were given bath treatment with cortisol (hydrocortisone, 0.2 mg L?1), 3,5,3′‐triiodothyronine (T3, 2.5 mg L?1) and a combination of cortisol and T3 for 30 min. Digestive enzyme profile was recorded on every third day and was continued for 30 days. Larvae were fed with live food for initial 14 days and then weaned to mix feeding of live food and prepared diet. Significantly (P < 0.05) higher amylase, total protease, trypsin, chymotrypsin, lipase, chitinase and chitinobiase activities were found in the hormone‐treated groups compared to the control one during ontogenic development. Among the treated groups, amylase activity was highest in cortisol‐treated larvae. Total protease, trypsin, chymotrypsin, lipase, chitinase and chitinobiase activities were significantly (P < 0.05) higher in larvae exposed at combined treatment of cortisol and T3 compared to the other two groups in most sampling days. Average length, weight and specific growth rate of treated larvae were higher compared to the control one. The combined bath treatment of cortisol and triiodothyronine influenced the digestive enzyme activities of catla larvae and thereby enhanced the growth at early developmental stage. This helps the larvae to overcome the problems associated with early developmental stage.  相似文献   
33.
Isolation and enumeration of amylase, cellulase and protease‐producing autochthonous bacteria in the proximal intestine (PI) and distal intestine (DI) of three species of Indian major carps, catla (Catla catla), mrigal (Cirrhinus mrigala) and rohu (Labeo rohita), were investigated using the conventional culture‐based technique. Population levels of amylolytic strains were the highest in the PI of catla and the lowest in the DI of rohu. The highest viable count of cellulase and protease‐producing bacteria was recorded in the DI and PI of mrigal respectively. Among the bacteria isolated, 10 strains (five from PI and five from DI) were selected as potent enzyme producers according to a quantitative enzyme assay. The chosen strains were further identified by 16S rRNA gene sequence analysis. The five strains isolated from catla showed high similarity to Citrobacter sp. clone W2, Enterobacter sp. JA24, Bacillus coagulans strain TR, uncultured bacterial clone Hel3bc04 and Bacillus cereus strain UST2006‐BC004. The four strains isolated from mrigal were most closely related to Bacillus sp. KCd2, uncultured bacterial clone Hel3bd09, B. cereus strain BU040901‐020 and Citrobacter freundii strain YRL11, while the strain isolated from rohu probably belonged to Bacillus sp. GV.  相似文献   
34.
35.
Calli were obtained from leaf, cotyledon and internode explants of in vitro-grown plants of Indian cultivar of Withania somnifera in MS medium supplemented with 2, 4-D (2.0 mg l−1) and Kinetin (0.2 mg l−1). The brown, semi-friable callus (500 mg FW) derived from leaf explants produced higher number of primary adventitious roots (9 roots/callus) in half strength MS medium fortified with IBA (0.5 mg l−1) and NAA (0.1 mg l−1). The primary adventitious roots with an inoculum mass of 15 g FW were cultured for 6 weeks in the same medium for secondary adventitious root proliferation. Elicitation of abiotic elicitor, aluminium chloride at 10 mg l−1 at the end of 4 weeks culture with 4 h exposure time enhanced withanolides productivity. Under similar culture conditions, the biotic elicitor, chitosan at 100 mg l−1 stimulated higher production of all withanolides when compared to aluminium chloride treatment. This is the first report on the use of callus-derived adventitious root culture for the enhanced production of withanolides upon chitosan elicitation.  相似文献   
36.
A new class of polyol esters were prepared by esterification of 10-undecenoic acid (UDA) with three polyols namely trimethylolpropane (TMP), neopentyl glycol (NPG) and pentaerythritol (PE) in 92-96% yields. The esters were characterized by IR, 1H NMR, HPLC and mass spectral studies. Polyol esters were evaluated for basic lubrication properties and found to be: viscosity at 40 °C, 11.2-36.1 cSt; at 100 °C, 3.2-7.3 cSt; viscosity index (VI), 162-172; pour point +3 to −36 °C; flash point, 254-296 °C. All the three polyol esters synthesized exhibited good thermal stability with TGA onset temperatures above 260 °C. The lubricating properties of the products compared well with polyol esters based on oleic acid.  相似文献   
37.
Commercial Marek's disease (MD) vaccines produced by two manufacturers were tested for possible contamination with avian leukosis virus (ALV). Samples of MD vaccines manufactured by two companies (A and B) were received from a breeder company; samples were also received directly from vaccine company B. Using virus isolation tests, samples initially tested positive for subgroup E (endogenous) ALV. However, upon repassage, the vaccines also tested positive for exogenous ALV. The isolated exogenous ALV proved to be a subgroup A virus, as determined by flow cytometry using polyclonal chicken antibodies specific for various subgroups of ALV, and by DNA sequencing of the envelope glygoprotein (gp85). The exogenous ALV isolated from MD vaccines was inoculated in chickens from ADOL lines 15I(5) x 7(1) and 0 to determine its pathogenicity and compare it with that of Rous-associated-virus-1 (RAV-1), the prototype strain of ALV-A. Each chicken from each line was inoculated with approximately 10,000 infectious units of RAV-1 or the ALV-A isolated from vaccines termed B-39 virus at 7th day of embryonation. At hatch, and at 4, 8, and 16 wk of age, chickens were tested for viremia and cloacal shedding; chickens were also observed for ALV-induced tumors within 16 wk of age. Viremia and cloacal shedding results suggest that chickens from both lines were susceptible to infection with either virus. Within 16 wk of age, the proportion of ALV tumors induced by strain B-39 in line 0 and line 15I5 x 7(1) chickens was 0% and 12%, respectively, compared with 62% and 67% in chickens inoculated with RAV-1. The data indicate that commercial MD vaccines produced by two manufacturers were contaminated with endogenous subgroup E and an exogenous subgroup A ALV. Further, data from biological characterization suggest that the ALV-A isolated from commercial MD vaccines is of low oncogenicity, compared with that of RAV-1. GenBank accession numbers: The gp85 gene sequences of ALV isolated from commercial Marek's disease vaccines have been deposited in GenBank and assigned the following accession numbers: A46 subgroup A, DQ412726 ; B53 subgroup A, DQ412727; A46 subgroup E, DQ412728; B53 subgroup E, DQ412729.  相似文献   
38.
Potato processing in India has shown a tremendous growth in the recent past, creating a proportionate increase in demand for processing quality potatoes. Reliable annual demand estimates of processing quality potato tubers in India were not available; hence, the current study was undertaken to provide such estimates. The study was based on a survey of 442 households in the state Maharashtra in India, which was regarded to be representative for India in the consumption of processed potato products. The annual expenditure on potato products during 2006–2007 in Maharashtra was estimated to be INR 5,254 million (€ 93.82 million), which was equivalent to 28,148 Mg of physical processed potato products and 83,333 Mg of processing quality potato tubers (0.38% of national potato production during 2006–2007, i.e. 22.09 million Mg). When the estimates were generalised to a national level, the requirement of processing-quality potato tubers in 2006–2007 was equal to 4.04% of national potato production. The forecasted annual demand of potato products in Maharashtra during 2011–2012 was 75,375 Mg and the corresponding demand of processing quality potato tubers was 230,760 Mg (0.75% of the estimated national potato production during 2011–2012, i.e. 30.89 million Mg). When generalised at national level, the demand of processing quality potato tubers during 2011–2012 was found to be 8% of the estimated national potato production.  相似文献   
39.
This paper presents the low stress mechanical properties of plain fabrics woven from cotton, bamboo viscose and cotton-bamboo viscose blended yarns. Three blends (100 % cotton, 50:50 cotton-bamboo and 100 % bamboo) were used to produce three yarn counts (20, 25 and 30 Ne). Each of these yarns was used to make fabrics with different pick densities (50, 60 and 70 picks per inch). It was found that bending rigidity, bending hysteresis, shear rigidity, shear hysteresis and compressibility is lower for bamboo fabrics as compared to those of 100 % cotton fabrics. On the other hand, extensibility, tensile energy and compressional resilience are higher for 100 % bamboo fabrics than 100 % cotton fabrics. Higher pick density increases linearity of load-elongation curve, bending rigidity, shear rigidity and compressional resilience. Shear and bending rigidities show very good correlation with the respective hysteresis values.  相似文献   
40.
Leveraging the antibacterial properties of polyester-cotton knitted fabrics has been attempted in this research by admixture of small proportion of polyester-silver nanocomposite fibres. Polyester-cotton (50:50) yarns were spun by mixing 10, 20 and 30 % (wt.%) polyester-silver nanocomposite fibres with normal polyester fibres so that overall proportion of polyester fibre becomes 50 %. The proportion of cotton fibre was constant (50 %) in all the yarns. Three parameters, namely blend proportion (wt.%) of nanocomposite fibres, yarn count and knitting machine gauge were varied, each at three levels, for producing 27 knitted fabrics. Polyester-cotton knitted fabrics prepared from polyester-silver nanocomposite fibres showed equally good antibacterial activity (65-99 %) against both S. aureus and E. coli bacteria. Antibacterial properties were enhanced with the increase in the proportion of polyester-silver nanocomposite fibres, yarn coarseness and increased compactness of knitted fabrics. Yarn count and blend proportion of nanocomposite fibre were found to have very dominant influence in determining the antibacterial properties of knitted fabrics.  相似文献   
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