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91.
枇杷叶总黄酮提取工艺研究 总被引:6,自引:0,他引:6
研究了从枇杷叶中提取黄酮的生产工艺.将枇杷叶煎煮液经大孔树脂吸附,用70%乙醇洗脱,洗脱液浓缩后用乙醇溶解,沉淀去杂后减压浓缩,经真空干燥,得到黄色粉末,其黄酮含量43%以上. 相似文献
92.
以龙泉枇杷为原料研究枇杷果酒生产工艺,考察不同发酵温度、糖浓度对果酒质量的影响.结果表明,发酵温度和糖浓度对酒的品质有比较明显的影响. 相似文献
93.
Huaijing Rui Shifeng Cao Haitao Shang Peng Jin Kaituo Wang Yonghua Zheng 《Journal of the science of food and agriculture》2010,90(9):1557-1561
BACKGROUND: Chilling injury (CI) limits the storage period and shelf‐life of red‐fleshed loquat fruit (Eriobotrya japonica Lindl.), which leads to a remarkable loss after cold storage. To develop an effective technique to reduce CI, the effects of a 38 °C heat treatment in air for 5 h, plus storage at 1 °C for 35 days, on internal browning (IB) and membrane fatty acid composition of the loquat cv. Jiefangzhong were investigated. RESULTS: Heat treatment delayed the occurrence of IB and inhibited the increase of IB index in ‘Jiefangzhong’ loquat fruit. Heat treatment maintained lower levels of electrolyte leakage and malondialdehyde content, and inhibited the increases in phospholipase D and lipoxygenase activities compared with the control fruit. Meanwhile, heat treatment inhibited the increases in palmitic, stearic and oleic acid levels and delayed the decreases in linoleic and linolenic acid contents, thus maintaining higher unsaturated/saturated fatty acid ratio than the control. CONCLUSION: These results suggest that the reduction of IB in chilled loquat fruit by heat treatment might due to maintenance of membrane integrity and higher unsaturated/saturated fatty acid ratio. Copyright © 2010 Society of Chemical Industry 相似文献
94.
大五星枇杷果实大,果皮、果肉颜色金黄,汁液丰富,糖分高,是制作罐头和酿酒的好原料。以新鲜大五星枇杷果实为原料,对其酿酒工艺进行了研究,对产品质量进行了综合评价,并通过正交设计,对成品酒调配进行了优化配方研究。 相似文献
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96.
Haiyan Gao Fei Tao Lili Song Hangjun Chen Wenxuan Chen Yongjun Zhou Jinlin Mao Yonghua Zheng 《Journal of the science of food and agriculture》2009,89(7):1159-1163
BACKGROUND: Loquat fruit is susceptible to microbial decay and quality deterioration during postharvest distribution. In this study, in a search for effective alternatives to methods currently used for quality maintenance, the effects of short‐term pre‐storage N2 treatment on the quality and antioxidant ability of loquat fruit were investigated. RESULTS: Loquat fruits were exposed to 100% N2 for 6 h at 20 °C and then stored at 5 °C for 35 days. Short‐term N2 treatment significantly delayed the increase in fruit decay rate and decreases in total soluble solid and titratable acidity contents, thereby maintaining better eating quality and extending the storage life of fruits. It also markedly delayed increases in membrane permeability, malondialdehyde content and superoxide anion production rate. In addition, N2‐treated fruits exhibited significantly higher superoxide dismutase and catalase activities and lower lipoxygenase activity than control fruits. CONCLUSION: Short‐term pre‐storage N2 treatment effectively reduced fruit decay and maintained quality in loquat fruits during cold storage. The reduction in fruit decay and quality deterioration by the treatment was correlated with enhanced antioxidant ability and reduced lipid peroxidation. Copyright © 2009 Society of Chemical Industry 相似文献
97.
Kei Tamaya Toshiro Matsui Asami Toshima Mai Noguchi Qiu Ju Yuji Miyata Takashi Tanaka Kazunari Tanaka 《Journal of the science of food and agriculture》2010,90(5):779-783
BACKGROUND: In the field of food science, much interest has been focused on the development of alternative medicinal foods with the ability to regulate excess blood glucose level (BGL) rise. The authors have successfully developed a new fermented tea product (LG tea) by co‐fermentation of loquat (Eriobotrya japonica) leaf and summer‐harvested green tea leaf. The objective of this study was to examine the acute suppression effect of LG tea on BGL rise in disaccharide‐loaded Sprague‐Dawley (SD) rats and to evaluate its possible usage as an antidiabetic functional food material. RESULTS: As a result of single oral administration of hot water extract of LG tea (50 mg kg?1) to maltose‐loaded SD rats, BGL at 30 min was significantly decreased by 23.8% (P < 0.01) compared with the control. A corresponding reduction in serum insulin secretion was also observed. The ED50 value of LG tea (50.7 mg kg?1) was estimated to be about 16‐fold higher than that of the therapeutic drug acarbose (3.1 mg kg?1). CONCLUSION: No significant change in BGL was observed when sucrose or glucose was administered, suggesting that the suppression effect of LG tea was achieved by maltase inhibition, not by sucrase inhibition or glucose transport inhibition at the intestinal membrane. Copyright © 2010 Society of Chemical Industry 相似文献
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Asami Toshima Toshiro Matsui Mai Noguchi Ju Qiu Kei Tamaya Yuji Miyata Takashi Tanaka Kazunari Tanaka 《Journal of the science of food and agriculture》2010,90(9):1545-1550
BACKGROUND: A new fermented tea produced by tea‐rolling processing of loquat (Eriobotrya japonica) leaf with green tea leaf (denoted as LG tea) showed a potent antihyperglycaemic effect in maltose‐loaded rats. The aim of this study, therefore, was to identify α‐glucosidase inhibitors in the antihyperglycaemic tea product. RESULTS: LG tea had a threefold higher maltase‐inhibitory activity (IC50 0.065 mg dried extract mL?1) than either the constituent loquat leaf or green tea alone. In addition, LG tea favourably inhibited maltase action rather than sucrase action. As a result of bio‐guided high‐performance liquid chromatography separations of LG tea, theasinensin A, theasinensin B, strictinin and 1,6‐digalloylglucose were newly identified as maltase inhibitors with IC50 values of 142, 225, 398 and 337 µmol L?1 respectively, along with previously identified catechins and theaflavins. CONCLUSION: Judging from the magnitude of the α‐glucosidase‐inhibitory contribution of each isolated compound to the overall inhibition of LG tea, catechins were the main candidates responsible for α‐glucosidase or maltase inhibition in LG tea, followed by theaflavins, theasinensins, strictinin and 1,6‐digalloylglucose. Copyright © 2010 Society of Chemical Industry 相似文献
99.
目的采用响应面法优化枇杷幼果总黄酮提取工艺,并考察其抗氧化活性。方法以总黄酮含量作为评价指标,以料液比、乙醇浓度、提取温度、提取时间为考察因素,采用单因素实验与响应面分析相结合的方法,探索最佳提取工艺,并采用总抗氧化能力检测试剂盒(total antioxidant capacity assay kit,ABTS)、1,1-二苯基-2-三硝基苯肼(1-diphenyl-2-picrylhydrazyl,DPPH)和亚铁还原能力实验(fluorescence recovery after photobleaching,FRAP)法分析其抗氧化活性。结果枇杷幼果总黄酮的最佳提取工艺为:液料比为1:64(g:mL),乙醇浓度为49%,提取温度为65℃,提取时间为20 min。在此条件下,枇杷幼果总黄酮的实际得率为76.038 mg/g,与预测得率75.046 mg/g接近。提取的枇杷幼果总黄酮经AB-8大孔树脂纯化,其抗氧化活性明显高于维生素C(VC)。结论响应面法提取枇杷幼果总黄酮工艺可行,且提取物具有很好的抗氧化活性。 相似文献
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以枫香叶分离物(枫香叶依次经乙醇提取、乙酸乙酯萃取、大孔树脂层析、50%乙醇洗脱后所得产物)为实验材料,分别研究其还原力及对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基、O2-·、·OH的清除能力和对枇杷的贮藏保鲜效果。用10、30、50 mg/100 mL的枫香叶分离物溶液对枇杷果实进行浸泡处理,6 ℃贮藏,每5 d测定一次枇杷果实的腐烂指数、硬度、可溶性固形物含量、可滴定酸含量、相对电导率、过氧化物酶(POD)活性、苯丙氨酸解氨酶(PAL)活性、木质素含量等果实的品质和生理指标。结果表明:枫香叶分离物具有较高的还原力和DPPH自由基、O2-·、·OH清除率;且枫香叶分离物处理可以有效控制枇杷果实腐烂指数、硬度、细胞膜渗透性及PAL活性和POD活性的升高,延缓可溶性固形物、可滴定酸含量的下降和木质素的积累,对于长期贮藏的枇杷果实具有较好的保鲜作用,其中以10 mg/100 mL枫香叶分离物的实用性较好。 相似文献