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排序方式: 共有2062条查询结果,搜索用时 171 毫秒
1.
Maria A. Ospina Monica Pizarro Thierry Tran Julien Ricci John Belalcazar Jorge L. Luna Luis F. Londoño Sandra Salazar Hernan Ceballos Dominique Dufour Luis A. Becerra Lopez-Lavalle 《International Journal of Food Science & Technology》2021,56(3):1343-1353
The objective of this study was to characterise the nutritional potential of leaves and identify a diversity centre with low cyanide and high nutrient content among 178 Latin American cassava genotypes. This field-based collection represents the seven diversity centres, held at The International Center for Tropical Agriculture (CIAT Palmira, Colombia) by the Cassava Program. The cyanide, all-trans-β-carotene and lutein concentrations in cassava leaves ranged from 346 to 7484 ppm dry basis (db), from 174–547 μg g−1 db and 15–181 μg g−1 db, respectively. Cassava leaves also showed significant levels of essential amino acids leucine, lysine, phenylalanine, valine and threonine, and average total protein content of 26.24 g 100 g−1 db. Among seven diversity centres, South American rainforest group showed low cyanide and high carotene content in leaves. In addition, VEN77 and PAN51 genotypes stood out for having low cyanide in leaves and roots and high carotene in leaves. This genetic diversity can be used to select high potential progenitors for breeding purposes. 相似文献
2.
蒋志斌 《徐州工程学院学报》2002,(1)
对新鲜茶树叶中六六六和滴滴涕共八种异构体的残留量进行测定,与同地点成品茶叶农药残留量相比较基本无差异。本法检测限为>1.8ng/g,回收率为78.2%-99.0%,相对标准偏差<10.0%。 相似文献
3.
Frdric Ampe Alain Brauman Serge Treche Aurelien Agossou 《Journal of the science of food and agriculture》1994,65(3):355-361
Retting, a spontaneous and traditional fermentation of cassava roots in Central Africa, was optimised in terms of time and the quality of the end-product. Optimal conditions were achieved by using an experimental research methodology. Temperature is the most influential factor, with an optimum of 34°C for quicker retting. The roots should be peeled and soaked in water immediately after harvesting to increase the quality of cassava foods. Inoculation of water with juice from a prior retting helps in cassava detoxification but has no influence on the time or the quality of foo-foo. Foo-foo samples had the most favourable organoleptic quality when an incubation temperature of between 28 and 37°C was used. Using optimal conditions, retting time was reduced 3-fold, and foo-foo of high and constant quality could be processed. 相似文献
4.
Osasere Faraday F. Orumwense 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1994,60(4):405-411
Dispersion–flocculation studies on a Goethite–clay system using flocculants were carried out as a function of flocculant concentrations, pH of slurry, time of agitation and dispersant dosage. Also, the effects of pH and polymer concentrations on the adsorption behaviour of the system were investigated. Results show that well flocculated goethite was preferentially obtained from 4% goethite/kaolinite clay suspensions, with 50 ppm causticised starch in the slurry at pH values of 3–11·5 and with 50 ppm polyacrylamide at pH values of 3–8. Good flocs were also obtained on flocculation of the goethite suspension with 50 ppm polyacrylamide at pH values of 5–7, while the kaolinite suspension did not respond to the same dosage of causticised starch in the same pH range. Results further reveal that for the goethite/kaolinite suspension, the best results was obtained with 50 ppm polyacrylamide at pH values of 7–10. Based on the data generated in the study, it was concluded that causticised starch is a better flocculant than polyacrylamide for goethite suspensions although polyacrylamide is an excellent flocculant for kaolinite suspensions. 相似文献
5.
针对叶片垂直分片机使用过程中出现的劈坏烟箱、纵向移动刀架失控和系统无报警功能等问题,分析故障产生的原因,并对其控制系统进行改进。 相似文献
6.
首先介绍了三种动力学模拟超临界流体萃取的模型(经验模型、基于热传递类推的模型以及基于微分质量平衡的模型),然后模拟了在超声存在的条件下超临界流体从香椿叶中萃取黄酮类化合物的动力学过程,最后通过该例子展示了现有大多数动力学模型的缺点. 相似文献
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9.
银杏叶中四种银杏内酯的含量测定 总被引:3,自引:0,他引:3
建立HPLC-ELSD法测定了30批银杏叶中4种银杏内酯的含量,并对所得数据进行分析研究.色谱条件为:phenonoonon C18色谱柱(250 mm×4.6 mm,5 μm),35%(体积分数)甲醇为流动相,1.000 mL/min的流速,ELSD检测器漂移管温度为60 ℃,氮气压力为1.72×105 Pa.得出红土栽培,未嫁接,树龄6~7 a的银杏叶中银杏内酯含量较高;4种银杏内酯总量集中在0.3%~0.5%(质量分数).该方法准确,重现性好,适用于银杏叶中4种银杏内酯的含量测定;银杏内酯的含量受生长环境影响差别较大,影响因素有待深入研究. 相似文献
10.
银杏叶中黄酮类化合物的提取工艺研究 总被引:3,自引:0,他引:3
研究了乙醇-水体系浸取银杏叶中黄酮类化合物的工艺条件,通过分光光度法测定黄酮的含量并计算它的浸出率。根据黄酮类化合物浸出率的计算结果,选用70%乙醇溶液为提取剂,并通过正交试验给出了黄酮类化合物的最佳浸出条件:浸取温度70℃,固液比1∶20,浸取剂pH=8,银杏叶中黄酮类化合物的浸出率可达到92.2%。 相似文献