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81.
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83.
Protein isolates from hydrolyzed and unhydrolyzed shrimp waste were prepared using the pH shift method. The conditions for protein isolation from unhydrolyzed shrimp waste by the pH shift method were standardized with respect to waste to distilled water ratio (1:2.5, 1:5, 1:7.5, and 1:10 w/v) and the alkaline pH (9.0, 10.0, and 11.0) to which the waste was to be adjusted before protein precipitation for higher yield of protein isolate. The yield of precipitate with waste to distilled water ratio of 1:2.5 (17.3 ± 0.9) was lower (p < 0.05) compared to the other three dilutions. The pH to which the waste is adjusted before precipitating the proteins at pH 4.5 had no effect (p > 0.05) on the yield. The antioxidant activity of the protein isolate obtained by the pH shift method from unhydrolyzed waste was compared with that obtained from the waste hydrolyzed with Alcalase®. The DPPH scavenging activity of protein isolate after enzyme hydrolysis was significantly higher than that of protein isolate from unhydrolyzed waste. With respect to recovery of total antioxidant activity, protein isolation from unhydrolyzed waste was superior to hydrolyzed waste due to higher yield.  相似文献   
84.
Ammonia is present in the aquatic environment due to agricultural runoff, sewage effluents and decomposition of biological waste. High level of ammonium in the aquatic environment or in aquaculture farms is a serious problem for aquatic organisms. In the present investigation, the sublethal effects of total ammonia nitrogen (TAN) at 9.98 mg L?1 on plasma electrolytes (Na+, K+ and Cl?) level of Indian major carp Catla catla fingerlings was studied for a period of 35 days under semistatic conditions. Exposure of fish to sublethal concentration of TAN at 9.98 mg L?1 caused changes in the levels of plasma electrolytes (Na+, K+ and Cl?) compared with control fish. No mortality was observed in any group during the treatment period. The present study reveals that the levels of plasma sodium and potassium (except on 7th day) electrolytes were significantly (< 0.05) decreased throughout the study period. However, the decrease in plasma chloride level was found to be not significant when compared with control group. The present study concludes that the measurements of plasma electrolytes levels can be used as potential biomarkers for monitoring nitrogenous chemicals in aquatic environment.  相似文献   
85.
Indole Acetic Acid (IAA) producing bacterium was isolated from the Rhizosphere soil and identified as Rhizobium sp. and Bacillus sp., Optimization of Indole acetic acid production was carried out at different cultural conditions, such as pH, temperature and substrate with Rhizobium sp., Bacillus sp. and Rhizobium sp., produced higher amount of Indole acetic acid (6.1 mg mL(-1)) than the Bacillus sp., (4.4 mg mL(-1)) at pH 7 and 37 degrees C in the Bengal gram substrate. Partial purification of Indole acetic acid was done by Thin Layer Chromatography (TLC). In conclusion Rhizobium sp., appear to be a suitable soil microorganism for high level of IAA production.  相似文献   
86.
Cryomilling of rice starch was evaluated as a non-chemical way to modify starch structure and properties. Cryomilling in a liquid nitrogen bath (63–77.2 K) was done to Quest (10.80% amylose) and Pelde (20.75% amylose) rice starch at five different time frames (0, 15, 30, 45, and 60 min). The viscosity of the cryomilled rice starch decreased significantly (p < 0.05) with increasing milling duration, including peak viscosity, hot-paste viscosity, cold-paste viscosity, breakdown, and consistency. Increasing milling time significantly increased (p < 0.05) water solubility index and water absorption index. Infra-red spectroscopy and X-ray diffraction crystallography both showed that the crystallinity of the cryomilled starch decreased with increasing milling time. Differential scanning calorimetry (DSC) analyses showed that after 60 min cryomilling there was partial loss of crystallinity (86% for Quest and 91% for Pelde) of both cryomilled starches. The cryomilling process modified the rice starch by causing a loss of crystallinity, that reduced its pasting temperature and increased water absorption, and by fragmentation of starch (probably the amylopectin fraction) that reduced the viscosity and increased solubility.  相似文献   
87.
Pro-poor value chains intend to integrate smallholding farmers into high value markets to contribute to poverty alleviation and food security. Although income benefits of pro-poor value chains have been found, scant evidence exists regarding the potential for these markets to enhance food security. This study focuses on components of food access—dietary diversity, physical and financial access, and social acceptability—among households that participate in pro-poor value chains and non-participating households in the central highlands of Peru where development interventions have created high value market niches for the native potato varieties that smallholding farmers have conserved for thousands of years. Using a mixed methods approach, this study assessed dietary diversity among households that participate and do not participate in pro-poor value chains, as well as their perceptions of their food access. Findings indicated that households that participate in value chains have higher dietary diversity than non-participating households but that these differences are likely due to pre-existing differences in socioeconomic status rather than any causal effect provided by value chains. The study also concluded that while participation in pro-poor value chains sometimes enhance the purchasing power of participating households, they may also weaken financial access, important for both purchasing food and travel to make those purchases. Community perspectives also indicated concerns with the acceptability of diets, which cannot likely be comprehensively addressed by pro-poor value chains. Collectively, the findings from this study cast doubt on the assumption that a linear flow exists between pro-poor value chains and enhanced food access.  相似文献   
88.
Pigeonpea (Cajanus cajan [L.] Millspaugh) is an important multipurpose grain legume crop primarily grown in tropical and subtropical areas of Asia, Africa and Latin America. In Africa, the crop is grown for several purposes including food security, income generation, livestock feed and in agroforestry. Production in Eastern and Southern Africa (ESA) is however faced with many challenges including limited use of high‐yielding cultivars, diseases and pests, drought, under‐investment in research and lack of scientific expertise. The aim of this review is to highlight the challenges facing pigeonpea breeding research in ESA and the existing opportunities for improving the overall pigeonpea subsector in the region. We discuss the potential of the recently available pigeonpea genomic resources for accelerated molecular breeding, the prospects for conventional breeding and commercial hybrid pigeonpea, and the relevant seed policies, among others, which are viewed as opportunities to enhance pigeonpea productivity.  相似文献   
89.
Tropical Animal Health and Production - The present study was conducted to evaluate the efficacy of dietary supplementation of 0.5 and 1% of fatty acid (FA) compound containing conjugated linoleic...  相似文献   
90.
Adoption of pigeonpea hybrids in central and southern India is showing high impact with on‐farm yield advantages of >30%. The hybrid pigeonpea technology, the first in any legume crop, is based on a cytoplasmic‐nuclear male‐sterility (CMS) system. For a long‐term sustainability of hybrid programme, it is imperative that both nuclear diversity and cytoplasmic diversity are maintained among hybrid parents. In this context, a continuous search for new CMS‐inducing cytoplasms is necessary. This paper reports detection of maternal inheritance of male sterility in the progeny derived from a natural hybrid between a wild relative [Cajanus lineatus (W. & A.) Maesen comb. nov.] of pigeonpea and an unknown pigeonpea [Cajanus cajan (L.) Millsp.] genotype. In the present study, the male sterility was maintained up to BC7F1 generation by an advanced breeding pigeonpea line ICPL 99044. This male sterility inducing cytoplasm of C. lineatus was tagged as A6. In future, this CMS genetic stock can be used to develop a range of new pigeonpea hybrids with high yield and adaptation.  相似文献   
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