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1.
The ethanol and methanol extracts of Cassia auriculata flowers were screened for antioxidant activity. The antioxidant activity was determined by an improved assay based on the decolorization of the radical monocation of 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. The ethanol and methanol extracts of C. auriculata flowers showed antioxidant activity in both assays.  相似文献   
2.
There is a widely held view among smallholders that teak timber produced from small-scale agroforestry systems, especially home-garden forestry, fetches a lower price than that from conventional plantation forestry. To examine the veracity of this view, the wood quality attributes of teak from two home gardens in the district of Ernakulam (wet site) and Palakkad (dry site) in India were compared to those of forest plantation in Nilambur. The logs were graded using standard timber trade practices into high, medium and low quality as determined by the potential sawn timber grade-yield recovery pattern. Of 96 home garden teak logs (aged 35 years) from wet and dry sites, 59% belonged to timber Grade II–IV and the rest were classified as poles. Grade I logs (export quality) with a girth above 150 cm were not available from either of the homesteads. Faster-grown teak in the wet site produced large diameter logs (dbh 1.37 m) with average diameter of 39.6 cm, which is comparable to that of best site quality in India. In contrast, the average dbh for teak grown in the dry site was 24 cm as compared to the average dbh of 31 cm recorded from the same aged forest plantation in Nilambur. It was found that only 10% of logs belonged to Grade II timber and the rest fell under grades III and IV with more frequent visual defects. The sawn timber recovery percentage was lower for the dry site (66.8%), whereas there was no significant difference in grade from the wet and forest plantation sites, with recovery rates of 76.5% and 78.8%, respectively. The general notion that home garden teak has a large proportion of sapwood seems to be baseless, no significant difference being found between the heartwood-sapwood ratio of home-garden and forest plantation teak. Lack of appropriate silvicultural practices in home-garden forestry caused the production of more defective logs, adversely affecting the market price of timber.
Puthenpurayil Kumaran ThulasidasEmail:
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3.
Matured black pepper berries from 8 wild types, on chemical screening, showed wide variations in commercially important constituents. The results have been compared with those of the cultivated varieties. The possibility of exploitation of this information in black pepper quality improvement programmes is discussed.  相似文献   
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Aquaculture International - Pacific white shrimp (Penaeus vannamei) farming is an important commercial aquaculture production system contributing substantially to the economic and societal...  相似文献   
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Baitfish such as golden shiners are subjected to stress during harvesting, grading, and transport. Their small size makes it difficult to measure the stress response with the biological indicator cortisol using conventional assay methods for plasma. This paper examines the development and validation of methods for whole-body cortisol extraction from individual baitfish. Three types of extracts were tested: (1) an ethyl ether unaltered extract (UA); (2) an extract reconstituted in phosphate buffered saline (PBS); (3) an extract that had been increased in volume by the addition of food-grade vegetable oil (VO). These extracts were evaluated using validation tests with radioimmunoassays (RIA) and enzyme-linked immunosorbent assays (ELISA). The UA extract produced inadequate volumes of extract for multiple assays and could not be used for the determination of cortisol in a single fish. The PBS reconstitution method failed the precision recovery of serial dilutions (62.3%), linearity (R 2: 0.7864), and parallelism validation tests. The VO volume-boosting method passed all validation tests [intra-assay coefficent of variation (%CV): 16.3 for ELISA and 5.9 for RIA; inter-assay %CV: 10.3; spiked recovery: 102.0%; dilution recovery: 93.0%; linearity R 2: 0.9435; log of serial dilutions was parallel] and provided enough extract for multiple assays from an individual baitfish. Based on these results, we conclude that the VO volume-boosting method presents a means for determining cortisol from individual baitfish using either RIA or ELISA assays.  相似文献   
8.
An activity-directed fractionation and purification process was used to identify the nitric oxide (NO) scavenging components of Phyllanthus emblica. Dried fruit rind of P. emblica was extracted with methanol and then separated into hexane, ethyl acetate, and water fractions. Among these only the ethyl acetate phase showed strong NO scavenging activity in vitro, when compared with water and hexane phases. The ethyl acetate fraction was then subjected to separation and purification using Sephadex LH-20 chromatography. Five compounds showing strong NO scavenging activity were identified by spectral methods (1H NMR, 13C NMR, and MS) and by comparison with literature values to be Gallic acid, Methyl gallate, Corilagin, Furosin, and Geraniin. In addition, HPLC identification and quantification of isolated compounds were also performed. Gallic acid was found to be a major compound in the ethyl acetate extract and Geraniin showed highest NO scavenging activity among the isolated compounds.  相似文献   
9.
Coconut, Cocos nucifera L. is an important plantation crop of the tropics. Lakshadweep group of islands in the Arabian Sea are considered to be home to some important coconut cultivars. The present exploration was planned to sample the variability within the population of Laccadive ordinary tall (LCT), Laccadive micro tall (LMT) from two islands, Amini and Kadmat, of Lakshadweep. Sampling was done from 24 sites in Amini and 13 sites in Kadmat. On an average 10 palms were sampled from each site. During the trip, five accessions of LCT, three of LMT and one of Kaithathali were collected. Eight fruit component measurements were recorded to study the variability in the population. Intra-population variability was observed in both LCT and LMT. Three forms of LCT belonging to niu kafa, niu vai and introgressed types could be identified. Elongated angular fruits (elliptical) with 70% husk were niu kafa types, round or oval shaped ones with 55% husk were niu vai types and pear shaped ones with 58% husk were the introgressed forms. This exploration trip unearthed the missing link of niu vai type in the form of round fruit type which has not been reported earlier. Identification of different groups in LCT has far reaching implications in breeding. In the production of hybrids involving LCT, selection of mother palms of LCT is crucial. It is suggested that the elliptical fruit types may be avoided in the production of commercial hybrids, since it has high percentage of husk.  相似文献   
10.
Coconut palm is a multipurpose crop cultivated in tropics. Diversity in this crop is rich in South Pacific Ocean and Indian Ocean Islands. Foliar traits have not been studied extensively to understand the diversity. Seven traits relevant to wind tolerance, dry matter production and taxonomic discrimination known in palms are used in the study. An attempt was made using Shannon–Weaver index with an objective to understand the level of diversity for these traits in a germplasm collection from diversity hotspot areas. Seven tall groups and four dwarf groups representing seven island territories were studied using 206 individuals. Diversity estimate was the highest in Nicobar tall group whereas it was low in tall genotypes of Fiji and Tonga. Thickness of leaf sheath fiber of weft and warp strands had shown high diversity estimates. Results obtained in this study were analyzed in relation to adaptation, geographical affinity, mating system and taxonomic forms (typica and nana) along with the importance of foliar traits in diversity of coconut. *CPCRI Contribution No. 1181  相似文献   
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