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481.
Maywan Hariono Jeffry Julianus Ipang Djunarko Irwan Hidayat Lintang Adelya Friska Indayani Zerlinda Auw Gabriel Namba Pandu Hariyono 《Molecules (Basel, Switzerland)》2021,26(22)
Carica papaya (papaya) leaf extract has been used for a long time in a traditional medicine to treat fever in some infectious diseases such as dengue, malaria, and chikungunya. The development of science and technology has subsequently made it possible to provide evidence that this plant is not only beneficial as an informal medication, but also that it has scientifically proven pharmacological and toxicological activities, which have led to its formal usage in professional health care systems. The development of formulations for use in nutraceuticals and cosmeceuticals has caused this product to be more valuable nowadays. The use of good manufacturing practice (GMP) standards, along with the ease of registering this product facilitated by policies of the national government, will absolutely increase the value of papaya leaf extract as a vital nutraceutical and cosmeceutical products in the near future. In this article, we review the potential of papaya leaf extract to be a high-value commodity in terms of its health effects as well as its industrial benefits. 相似文献
482.
为了更好地探究酸性水稻土中有效态砷和糙米砷含量的相关性,采用土液比1:10、振荡时间240 min和振荡速度200 r·min-1为中间条件,比较4种浸提剂0.01 mol·L-1 CaCl2-DTPA,0.5 mol·L-1 NaHCO3,0.05 mol·L-1 NH4H2PO4和0.43 mol·L-1 HNO3提取酸性水稻土中有效砷的提取效果。结果表明,4种浸提剂提取的土壤有效态砷与其糙米砷含量之间均存在显著相关,0.43 mol·L-1 HNO3提取的土壤有效态砷与糙米砷含量的相关性最高为0.828,土壤有效态砷平均提取率最高为8.63。选择0.43 mol·L-1 HNO3为提取酸性水稻土有效态砷的最优浸提剂,进一步优化浸提剂的提取条件,确定土液比1:10、振荡时间120 min和振荡速度200 r·min-1为酸性水稻土有效态砷最佳提取条件,土壤有效态砷与糙米砷含量的相关性最高为0.831。0.43 mol·L-1 HNO3提取酸性水稻土中有效砷的方法操作简便、试剂用量少,提取的土壤有效砷和糙米砷的相关性好,确定为酸性水稻土有效态砷的提取方法,为科学评价酸性水稻土壤有效态砷与糙米砷的生物有效性以及酸性水稻土壤砷环境风险评价提供参考依据。 相似文献
483.
Hurok Oh Young-Jung Wee Jong-Sun Yun Hwa-Won Ryu 《Applied biochemistry and biotechnology》2003,107(1-3):603-613
The effect of various nitrogen sources on cell growth and lactic acid production was investigated. The most effective nitrogen
source was yeast extract; more yeast extract gave higher cell growth and lactic acid productivity. Yeast extract dosage and
cell growth were proportional up to a yeast extract concentration of 30 g/L, and lactic acid productivity was linearly correlated
up to a yeast extract dosage of 25 g/L. However, increasing the yeast extract content raises the total production cost of
lactic acid. Therefore, we attempted to find the optimum yeast extract dosage for a repeated-batch operation with cell recycling.
The results show that when using Enterococcus faecalis RKY1 only 26% of the yeast extract dosage for a conventional batch fermentation was sufficient to produce the same amount
of lactic acid, whereas the lactic acid concentration in the product stream (92–94 g/L) and lactic acid productivity (6.03–6.20
g/[L·h]) were similar to those of a batch operation. Furthermore, long-term stability was established. 相似文献
484.
Simultaneous quantification of 25 active constituents in the total flavonoids extract from Herba Desmodii Styracifolii by high‐performance liquid chromatography with electrospray ionization tandem mass spectrometry 下载免费PDF全文
Panpan Guo Wenying Yan Qingjie Han Chunying Wang Zijian Zhang 《Journal of separation science》2015,38(7):1156-1163
A sensitive and selective high‐performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry method has been developed and validated for the simultaneous determination of 25 active constituents, including 21 flavonoids and four phenolic acids in the total flavonoids extract from Herba Desmodii Styracifolii for the first time. Among the 25 compounds, seven compounds including caffeic acid, acacetin, genistein, genistin, diosmetin, diosmin and hesperidin were identified and quantified for the first time in Herba Desmodii Styracifolii. Chromatographic separation was accomplished on a ZORBAX SB‐C18 (250 mm×4.6 mm, 5.0 μm) column using gradient elution of methanol and 0.1‰ acetic acid v/v at a flow rate of 1.0 mL/min. The identification and quantification of the analytes were achieved using negative electrospray ionization mass spectrometry in multiple‐reaction monitoring mode. The method was fully validated in terms of limits of detection and quantification, linearity, precision and accuracy. The results indicated that the developed method is simple, rapid, specific and reliable. Furthermore, the developed method was successfully applied to quantify the 25 active components in six batches of total flavonoids extract from Herba Desmodii Styracifolii. 相似文献
485.
486.
建立HPLC法测定桑叶提取物中水解槲皮素和山萘酚的含量.先用甲醇-盐酸混合液(甲醇终浓度50%,盐酸终浓度2.0mol·L^-1)水解桑叶提取物中的黄酮类成分成槲皮素和山萘酚,以HPLC法测定槲皮素和山萘酚含量.色谱柱为Diamonsil钻石C18柱,流动相为甲醇-0.2%磷酸(63:37,体积分数),流速为1.0mL·min^-1,检测波长为370nm.结果表明槲皮素在0.84~26.8μg·mL^-1之间,山萘酚在0.44~14.2μg·mL^-1之间呈良好的线性关系,平均回收率分别为101.3%和99.5%.该测定方法准确、重复性好,可用于桑叶提取物中槲皮素和山萘酚的含量测定. 相似文献
487.
488.
Xiao Yu ZHANG Feng Hua CHEN Ping Hui WEI Jia Zuan NI 《中国化学快报》2006,17(8):1105-1108
Epimedium, one of representatives of traditional Chinese herb, is mainly composed of flavones and polysaccharide. It is famous for its antioxidant, antineoplastic and antiaging activities and has been widely used in the field of invigorating kidney and st… 相似文献
489.
《Analytical letters》2012,45(5):895-907
Abstract An amperometric biosensor for the determination of phenols is proposed using a crude extract of sweet potato (Ipomoea batatas (L.) Lam.) as an enzymatic source of polyphenol oxidase (PPO; tyrosinase; catechol oxidase; EC 1.14.18.1). The biosensor is constructed by the immobilization of sweet potato crude extract with glutaraldehyde and bovine serum albumin onto an oxygen membrane. This biosensor provides a linear response for catechol, pyrogallol, phenol and p-cresol in the concentration ranges of 2.0×10?5-4.3×10?4mol L?1, 2.0×10?5-4.3×10?4 mol L?1, 2.0×10?5-4.5×10?4 mol L?1 and 2.0×10?5-4.5×10?4mol L?1, respectively. The response time was about 3–5 min for the useful response range, and the lifetime of this electrode was excellent for fifteen days (over 220 determinations for each enzymatic membrane). Application of this biosensor for the determination of phenols in industrial wastewaters is presented. 相似文献
490.
《Biomedical chromatography : BMC》2018,32(6)
A simple, sensitive and rapid liquid chromatography tandem mass spectrometry method (LC‐MS/MS) was developed and validated for the determination of plasma isoorientin levels in rats. After simple protein precipitation using methanol, chromatographic analysis was performed using a Synergi 4μ polar‐RP 80A column (150 × 2.0 mm, 4μm) under isocratic conditions and a mobile phase consisting of 0.1% formic acid in water and methanol (80:20, v/v) at a flow rate of 0.2 mL/min. In positive electrospray ionization mode, the protonated precursor and product ion transitions of isoorientin (m/z 449.0 → 299.1) and of puerarin (the internal standard; m/z 417.1 → 297.1) were acquired by multiple reaction monitoring. Calibration curves obtained for plasma showed good linearity over the concentration range 1–1000 ng/mL. The lower limit of quantification was 1 ng/mL. Intra‐ and inter‐day precisions were within 8.8% relative standard deviation. Accuracies ranged from 92.1 and 109.7%. The isoorientin stability in rat plasma under typical handling/storage conditions also found to be acceptable. The developed method was applied successfully to a pharmacokinetic study of isoorientin orally administered as the methanol extract of Vaccinium bracteatum Thunb. or administered as pure isoorientin. 相似文献