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81.
后季稻秧田健秧配剂的研制及其应用效果 总被引:1,自引:0,他引:1
在水稻秧田中使用二氯喹啉酸防除杂草,对水稻生长发育安全,应用多效唑矮化促蘖,有利于减轻水稻败苗,增加产量,这在后季稻秧田中已普遍使用。本试验在多配方中筛选出二氯喹啉酸与多效唑具有相互增效作用的基础上,添加助剂复配,就其含量比例、对 相似文献
82.
Santaclara FJ Espiñeira M Cabado AG Vieites JM 《Journal of agricultural and food chemistry》2007,55(2):305-310
In the present study a technique was developed with the aim of guaranteeing the composition and security of fish meals, since it allows verification of whether these meals contain land animal remains. The method is based on polymerase chain reaction (PCR) and length polymorphism, followed by a restriction fragment length polymorphism (RFLP). Specific primers for every species were designed and calibrated, generating exclusively a PCR product with a specific size when DNA for each species was present in the sample. This technique allows the detection of land animal remains in fish meals, specifically cow, chicken, pig, horse, sheep, and goat. The identity of the PCR products can be confirmed by RFLP analysis using only one restriction enzyme. The selected restrictase generated one characteristic restriction profile for every species included in this study. The detection limit of this method was calculated by using mixtures of fish meals in different proportions and meal that exclusively contained remains of one of these land species studied. The analytical strategy herein proposed was applied to fish and meat meals, giving good results, both in the analyzed standards and in commercial samples. 相似文献
83.
为研发高效硅肥和防治农田镉污染提供借鉴资料,本文综述了施加硅肥对水稻生长发育的影响,包括提高水稻产量和品质,增强抗倒伏、抗病虫害及干旱等逆境的能力,尤其是增强抗镉毒害等能力。并从生理学机制和土壤学机制两方面重点分析了施加硅肥对缓解镉毒害作用的可能机理。生理学机制方面:硅通过参与水稻的生理代谢活动,使水稻抗氧化系统酶的活性和清除自由基的能力增强;抑制镉的吸收及其在水稻体内的运输;硅与镉在水稻体内的螯合和区隔作用。土壤学机制方面:硅肥改变土壤理化性质,降低土壤中有效态镉的含量;硅镉吸附沉淀作用,减少水稻对镉吸收。最后针对硅肥的开发利用及技术推广提出展望。 相似文献
84.
以富含纤维素酶的茶叶半成品为原料试制速溶茶。首先采用单因素试验方法分析了此酶的酶学性质,再通过正交设计优化了速溶茶的浸提条件。结果表明,此纤维素酶适合在30~60℃、p H 3.5~5.5范围内反应;在30~40℃范围、p H 3.0~5.0范围内较稳定;50℃保温60 min后残余酶活为40%。浸提温度60℃、液固比20、浸提50 min为速溶茶的最佳浸提条件,茶汤中茶多酚浸出率达85.6%,与原料相比,氨基酸、可溶性糖、咖啡碱含量显著提高23.7%、6.3%、2.9%,水浸出率达96%。 相似文献
85.
利用刚毛藻处理水中NH3-N、NO3-N、NO2-N、TN、TP,选择藻量、温度、光照、处理时间作为控制因子,研究不同条件及实际不同水环境下刚毛藻对水中N、P控制的影响。结果表明,藻量控制在1.5 g/L时藻对水样中NH3-N、NO3-N、NO2-N、TN、TP的去除效果较好;T-P的去除速率较快,在5 d即能取得较好效果,其次是NH3-N,在12 d左右达动态平衡,T-N的去除14 d为适应处理时间;当温度为20℃时,NH3-N、NO3-N、NO2-N、TP水体处理效果较好,TN处理最适宜温度出现在30℃;光照则表现为照度3 000 lx±100 lx时,NH3-N、NO3-N、NO2-N、TP去除效果较好。刚毛藻对不同水环境的N、P处理,T-N、T-P、NO2-N、NH3-N的处理均能达到较好的处理效果,且差异明显,但对NO3-N处理效果不甚理想。 相似文献
86.
Cerdá B Periago P Espín JC Tomás-Barberán FA 《Journal of agricultural and food chemistry》2005,53(14):5571-5576
Dietary ellagic acid and related polyphenols are metabolized in humans to dibenzopyran-6-one derivatives, and the microbial origin of these metabolites has been suggested. However, this has not been demonstrated so far. Fecal samples donated by six volunteers were incubated under anaerobic conditions, and aliquots were used to evaluate the fecal metabolism of ellagic acid, the ellagitannin punicalagin, and an ellagitannin rich extract from walnuts. The isoflavone daidzein was also incubated with the same fecal samples to follow the production of the microbial metabolites previously reported (dihydrogenistein, O-demethylangolensin, and equol) as a positive control of the system and to evaluate similarities between isoflavone and ellagic acid fecal flora metabolism. After fermentation the metabolite "urolithin A" (3,8-dihydroxy-6H-dibenzo[b,d]pyran-6-one) was produced from ellagic acid, punicalagin, and the ellagitannin extract in all the fecal cultures from different volunteers, but with very different production rates and concentrations. This large variability in the concentration of metabolite and kinetics of metabolite production is consistent with the large variability found in the excretion of these metabolites in urine in vivo after human consumption of ellagitannins, and with differences in the composition of the fecal microflora. No correlation between isoflavone and ellagic acid metabolism by fecal microflora was observed. The present study confirms the microbial origin of the recently reported in vivo generated hydroxy-6H-dibenzo[b,d]pyran-6-one derivatives in humans and is a further step in the study of the bioavailability and metabolism of ellagic acid and ellagitannins. 相似文献
87.
Sampedro I Aranda E Rodríguez-Gutiérrez G Lama-Muñoz A Ocampo JA Fernández-Bolaños J García-Romera I 《Journal of agricultural and food chemistry》2011,59(7):3239-3245
Byproducts generated from food industries, such as olive oil mills, have been studied to decrease harmful pollution and their environmental consequences. In this work, a new thermal pretreatment and saprobic fungal incubation to detoxify alperujo (two-phase olive mill waste) have been evaluated in view of its use as fertilizer in agriculture. The sequential use of both methods simplifies the thermal conditions and incubation times of the fungal treatment. Optimization of the thermal treatment from 150 to 170 °C for 45 and 15 min, respectively, reduced the incubation time with Coriolpsis rigida from 20 to 10 weeks needed to reduce phytotoxic effects on tomato plants. Therefore, the combination of thermal and biological treatments will allow the development of the potential benefits of alperujo to improve nutrients in agricultural soil. 相似文献
88.
Cytoprotection by neutral fraction of tannat red wine against oxidative stress-induced cell death 总被引:1,自引:0,他引:1
Echeverry C Blasina F Arredondo F Ferreira M Abin-Carriquiry JA Vasquez L Aspillaga AA Diez MS Leighton F Dajas F 《Journal of agricultural and food chemistry》2004,52(24):7395-7399
Some of the beneficial effects of the Mediterranean diet on human pathologies have been attributed to red wine polyphenols. It has been postulated that the antioxidant activity of the latter would be also responsible for the cytoprotective capacity of red wine that has been reported in a few papers. Nevertheless, red wine shows a complex composition, and the active fraction is not known yet. In this context, the protective capacity of total lyophilized extracts of red wine and anthocyanin, neutral, or acidic fractions, was explored in PC12 cells in culture after a hydrogen peroxide insult. Although all fractions showed high antioxidant activity, only the neutral fraction was cytoprotective. The analysis of this active fraction showed that it was rich in the aglycons quercetin and myricetin as well as the glycosides of kaempferol, isorhamnetin, epicatechin, and catechin, some of which are known to be cytoprotective. This is the first paper to reveal the active fraction of total wine responsible of its cytoprotection. 相似文献
89.
新疆石榴果实品质主成分分析 总被引:1,自引:0,他引:1
【目的】对新疆石榴果实品质进行主成分分析,为新疆石榴品质综合评价提供理论参考。【方法】以新疆主栽石榴对象,测定和比较其果实可溶性固形物、可滴定酸、可溶性糖和VC含量,采用主成分分析对不同石榴的果实内在品质进行综合评价。【结果】不同石榴在果实品质上存在一定差异,其中叶城大籽甜石榴的可溶性固形物含量最高(17.9 %±0.6 %),喀什甜石榴最低(14.9%±0.5%);叶城酸石榴的可滴定酸含量最高(2.19%±0.38%),叶城酸石榴、喀什甜石榴、喀什酸石榴三者之间的可滴定酸含量没有显著差异;叶城甜石榴的可溶性糖含量最高(17.9%±0.6%),显著高于其他石榴;皮亚曼石榴的VC含量超过[(28.3 ±1.1) mg/100 g],显著高于其他石榴。【结论】通过主成分分析综合评判叶城大籽甜石榴内在品质最佳,其后依次是叶城甜石榴、皮亚曼石榴、叶城酸石榴、喀什甜石榴和喀什酸石榴。 相似文献
90.