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以二氯乙烷作溶剂,炔酸烯丙酯在K2CO3催化下,可以顺利发生分子内串联环化反应得标题化合物,产率65% ~88%.产物经1HNMR、13CNMR和GC-MS确证. 相似文献
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王维义许帅强何宏燕王威 《中国油脂》2020,45(4):83-85
亚麻籽是世界十大油料作物之一,营养价值较高。亚麻籽含有α-亚麻酸、亚麻籽蛋白、亚麻木酚素、膳食纤维和亚麻胶等多种营养成分,从而使亚麻籽具有降血糖、降血脂和预防心脑血管疾病等多种功能。对亚麻籽的营养成分及其功能研究进展进行综述,以期为促进亚麻产业发展提供参考。 相似文献
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为提高亚麻木酚素的纯度,在对提取液进行冷冻干燥前,用中空纤维超滤装置对亚麻木脂素提取液进行澄清、净化。以超滤理论为基础,建立了超滤过程中表达平均通量与膜进口压力关系的理论渗透模型。以试验数据为基础,对理论渗透模型进行求解,建立了适合本试验的简略渗透模型。验证试验表明,简略渗透模型能较好地预测中空纤维超滤膜澄清亚麻籽木脂素提取液的平均通量,试验值略高于计算值,最大绝对误差为2.9×10<sub>-6</sub>m<sub>3</sub>/(m<sub>2</sub>.s)),最大相对误差为3.8%。 相似文献
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为了确定高芝麻酚芝麻油的最适微波预处理条件,将芝麻水分含量调节为5个梯度,在不同微波预处理时间下制得芝麻油样品,对其芝麻木酚素含量、酸值、茴香胺值、氧化诱导时间、脂肪酸组成、生育酚含量、有害物质(多环芳烃和杂环胺)含量及感官品质进行了分析,探究芝麻水分含量和微波预处理时间对芝麻油中芝麻木酚素含量及油脂品质的影响。结果表明:微波预处理时间6 min、芝麻水分含量7%条件下制得的芝麻油芝麻酚含量较高,芝麻油酸值符合国家标准限定要求,氧化稳定性较强,有害物质杂环胺和多环芳烃含量处于适当的可控水平,同时兼顾了芝麻油的固有风味,消费者的喜爱度较高。综上,高芝麻酚芝麻油的最适微波预处理条件为微波预处理时间6 min,芝麻水分含量7%。 相似文献
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The aim of the study was to determine the effect of selected variables on fermentation of decoction of Saraca asoca bark to develop a suitable method for preparing its polyherbal formulation. S. asoca bark has been fermented using Wickerhamomyces anomalus (nonsaccharomyces yeast) and the method was optimized using response surface methodology (RSM). The independent variables, substrate volume (ml), temperature (°C), and time (hours), were optimized using three-factor, three-level Box–Behnken design to obtain the good content of secoisolariciresinol, lyoniresinol, and 5-methoxy isolariciresinol. Secoisolariciresinol and 5-methoxy isolariciresinol were first isolated from S. asoca bark. The method yielded a quadratic polynomial equation to predict the effect of independent variables on selected responses (<0.0001). All three variables significantly (p-value < 0.0001–0.0068) affected the selected responses. The experimental values agreed closely with the predicted values and the analysis of variance signified a good model fit. The optimum conditions were 67.03 ml substrate volume, 30.95°C, and 64.86 h resulting in 23.24, 21.20, 25.06 μg of secoisolariciresinol, lyoniresinol, and 5-methoxy isolariciresinol content. This is the first report of biotechnological production of Asokarista using W. anomalus in 48 h rather than 35 days as mentioned in traditional method. Also, secoisolariciresinol has been found in fermented S. asoca bark for the first time. It has been ascertained that W. anomalus causes deglycosylation in traditional ayurvedic formulations during fermentation. Present study proved the possibility of using pure strain, Wi. anomalus, for formulating traditional formulation. 相似文献
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Cong-Cong Zhuang Xu Feng Hai-Yan Xu Li Zhang Ling Liu Gong Zhang Zhong Zheng Chao-Mei Ma 《Journal of dairy science》2021,104(1):391-396
Mammalian lignans are phytoestrogens with important bioactivities, and their concentrations in livestock milk may influence the health of consumers. This research aimed to establish a method to quantify multiple mammalian lignans in the biofluids of dairy sheep using ultra-HPLC-triple quadropole mass spectrometry with multiple-reaction monitoring. Secoisolariciresinol, 2-[(4-hydroxy-3-methoxyphenyl)methyl]-3-[(3-hydroxyphenyl)methyl]-1,4-butanediol, enterodiol (ED), enterolactone (EL), ED-sulfate (ED-S), and EL-sulfate (EL-S) were purified from the urine of flaxseed cake–fed dairy sheep. The structures of these lignans were identified by a combination of mass and nuclear magnetic resonance spectra. These purified lignans were used as standards to optimize their quantification conditions in urine, milk, and plasma of dairy sheep. On this basis, the lignan metabolites in biofluids were quantified. To improve analysis sensitivity, plasma and milk were pretreated with acetonitrile containing 1% formic acid and passed through a HybridSPE-PL 55261-U column (Supelco, Bellefonte, PA). The limit of quantification of the lignans ranged from 1.43 to 18.3 ng/mL in plasma, and from 1.01 to 18.7 ng/mL in milk. The linearity of the calibration curves ranged from their limit of quantification to at least 217 ng/mL in plasma, and 217 ng/mL in milk. Regression coefficient of the calibration curves were above 0.99 for secoisolariciresinol, 2-[(4-hydroxy-3-methoxyphenyl)methyl]-3-[(3-hydroxyphenyl)methyl]-1,4-butanediol, ED, EL, ED-S, and EL-S, indicating satisfactory relationships between the peak areas and concentrations in the quantification range. The relative concentrations of ED-glucuronide and EL-glucuronide (EL-G) in different biofluids were compared based on their chromatogram peak areas. The sheep plasma contained all forms of mammalian lignans (i.e., ED, EL, ED-S, EL-S, ED-glucuronide, and EL-G.); the urine contained ED, EL, ED-S, and EL-S; and the milk contained ED, EL, ED-S, EL-S, and EL-G. Milk-to-plasma concentration ratios of the mammalian lignans indicated that the free forms were more permeable than the sulfated conjugates. Mammalian lignans found in sheep plasma and milk may provide health benefits to the sheep and sheep-product consumers. The analytical method established in this work could be used to quantify mammalian lignans in livestock products. 相似文献
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