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141.
Mbatia B Kaki SS Mattiasson B Mulaa F Adlercreutz P 《Journal of agricultural and food chemistry》2011,59(13):7021-7027
Lipase-catalyzed synthesis of lipophilic phenolic antioxidants was carried out with a concentrate of n-3 polyunsaturated fatty acids (PUFAs), recovered from oil extracted from salmon ( Salmon salar ) byproduct. Vanillyl alcohol and rutin were selected for the esterification reaction, and obtained esters yields were 60 and 30%, respectively. The antioxidant activities of the esters were compared with those of commercial butylated hydroxytoluene (BHT) and α-tocopherol using DPPH radical scavenging and thiobarbituric acid assays. In the DPPH assay, rutin esters showed better activity than vanillyl esters, and on the contrary in lipophilic medium, vanillyl esters were found to be superior to rutin esters. In bulk oil system, the antioxidant activities of rutin and vanillyl derivatives were lower than that of BHT and α-tocopherol, but in emulsion, they showed better activity than α-tocopherol. By attaching to natural phenolics, the PUFAs are protected against oxidation, and PUFA improves the hydrophobicity of the phenolic, which could enhance its function in lipid systems. 相似文献
142.
Biffa D Inangolet F Bogale A Oloya J Djønne B Skjerve E 《Tropical animal health and production》2011,43(2):529-538
This study was aimed at investigating risk factors associated with prevalence of tuberculosis (TB)-like lesions and associated
mycobacteria in Ethiopian cattle slaughtered. The study was carried out during 2006–2007 in five selected municipal and export
abattoirs. Methods of investigation involved detailed necropsy examination of carcasses and isolation of mycobacteria from
pathologic tissue specimens. Factors of animal and environment origin were recorded and examined as explanatory variables
in relation to the presence or absence of TB-like lesions and the presence of viable mycobacteria. Multivariable logistic
regression analysis was used to identify risk factors associated with prevalence of TB-like lesions and mycobacteria. Out
of 3,322 carcasses inspected, 10.2% (95% confidence interval (CI) [9.2–11.3]) and 3.2% (95% CI [2.6–3.8]) were positive, respectively,
based on necropsy and bacteriologic examinations. The highest and lowest lesion prevalence was recorded in Adama (24.7%) and
Yabello (4.2%), respectively. Multivariable logistic regression analysis identified age, breed, abattoir location, geographic
origin and management system as being risk factors for prevalence of TB-like lesions and occurrence of viable mycobacteria
in Ethiopian cattle. The study demonstrated mycobacterial infection as important infectious disease of Ethiopian cattle. The
reported confirmed cases of the disease in different management and geographic settings in Ethiopia disproved the earlier
held opinion of its occurrence as a low sporadic profile. In view of a dietary proclivity of Ethiopian communities (milk and
meat are predominantly consumed raw) and lifestyle (close contact of people with animals), the risk of bovine tuberculosis
as a public health threat is eminent. 相似文献
143.
144.
145.
Jalal Jamalian Francis Aylward Bertram J. F. Hudson 《Plant foods for human nutrition (Dordrecht, Netherlands)》1977,27(2):213-219
Ingestion of broad bean seeds will precipitate an acute haemolytic anaemia (favism) in certain sensitive subjects. Aqueous extracts from both fresh and dried mature broad bean seeds, obtained from a favism-endemic area in Iran, were incubated with blood from favism-sensitive and control subjects. Changes in the reduced glutathione content of red blood cells were determined as an index of toxicity. The results showed that:
- The toxic principles in broad beans were at least partially water soluble.
- The seed coats of dry mature seeds and the flesh from fresh seeds had low toxicity.
- The immature whole seeds and the seed coats of fresh mature seeds were toxic.
146.
Four of five major cultivars of the potato (Solanum tuberosum L. ssp.tuberosum) from different sources were found to vary genetically. This variability was detected by an electrophoretic study of enzymatic activity for alkaline phosphatase and glucosephosphate isomerase. An examination of red cultivars from Beltsville, Md. suggests that the apparent intracultivar variability observed for Red Pontiac may be due to cultivar mislabeling rather than mutation or mitotic recombination. The results of this study raise concerns about potato cultivar certification and interpretations of some of the previous cultivar work. We suggest that a more extensive survey of intracultivar variability be carried out. Further, we suggest that these genetic markers and others could be used in cultivar identification. 相似文献
147.
J. Bota M. À. Conesa J. M. Ochogavia H. Medrano D. M. Francis J. Cifre 《Genetic Resources and Crop Evolution》2014,61(6):1131-1146
Tomàtiga de Ramellet (Ramellet) is a traditional long-storage tomato from the Mediterranean Islands of Mallorca, Menorca, Eivissa (Ibiza), and Formentera (Balearic Islands). To investigate the observed phenotypic and shelf life variability within local varieties, we studied 142 accessions characterized as Ramellet varieties, and 29 accessions representing other local varieties. The 171 accessions constitute a new germplasm collection at the University of Balearic Islands (UIB). The evaluation of the collection demonstrated wide variability in most agronomic, morphological and quality traits of Ramellet accessions and clearly differentiates them from other local varieties with respect to fruit shape, size, fruit composition, and fruit storage. All accessions of Ramellet evaluated have the ripening mutation alcobaça (alc), suggesting an important role for this variant in controlling shelf life. Results of evaluation also showed wide variability between the Ramellet accessions for storage time, suggesting that other traits like fruit size and composition may play a role in fruit conservation. Observed variation within the Ramellet accessions is consistent with a genetically variable population or landrace group. The establishment of this collection will help prevent genetic erosion of this local landrace group and constitute a resource for future investigation and breeding. 相似文献
148.
Summary A cross was made between a unique highly branched, early flowering line, U. S. Department of Agriculture (USDA) 846-1 (P1; 7 to 11 lateral branches), and ‘Topmark’ (P2; 2 to 4 lateral branches), a U.S. Western Shipping melon, to produce an array of 119 F3 families. Subsequently, a genetic analysis was conducted at Arlington and Hancock, Wisconsin in 2001 to evaluate the segregating
progeny for factors likely involved in yield-formation, including days to anthesis, percentage of plants with early pistillate
flowering, primary branch number, fruit number and weight per plant, average weight per fruit, percentage of plants with predominantly
crown fruit set, and percentage of plants with early maturing fruit. Although, genotype × environment (G × E) interactions
were important for some traits (e.g., fruit number and fruit weight), considerable additive and/or dominance variance was
detected for all traits. This research provides critical data associated with highly branched melon germplasm including trait
correlations and heritabilies (broad- and narrow-sense ranged between 0.28 and 0.91) that used judiciously will allow the
development high yielding melon cultivars with early, basally concentrated fruit suitable for once-over or machine harvesting
operations. 相似文献
149.
150.
A simple trapping procedure for concentration of volatile organic compounds present in a head space and the subsequent analysis of the retained compounds by combined gas chromatographymass spectrometry is described. The procedure was used to study the organic metabolites evolved from various soils when they were amended with glucose and incubated under argon. A number of organic acids, alcohols, aldehydes and esters were evolved during a 4 week period. Less than 10 per cent of the added carbon was recovered as organic compounds, which was largely due to poor recovery of volatile organic acids from soil. Some implications of the observations to microbial ecology are discussed. 相似文献