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为了考察牛大力乙醇提取物中总黄酮的含量及抗氧化活性。通过L16(45)正交实验,超声波辅助提取牛大力中总黄酮,得到最佳工艺,再测试乙醇提取物和四个萃取物对羟基自由基(.OH)和DPPH自由基(DP-PH.)的清除效果。最佳工艺为:φ(EtOH)=75%、m(牛大力,g)∶V(EtOH,mL)=1∶25、温度60℃、时间60min,该条件下,牛大力总黄酮得率可达2.14mg.g-1。其中,牛大力乙醇提取物中氯仿萃取物中黄酮含量最高,为5.52mg.g-1;而且氯仿萃取物对DPPH.的清除效果最好,其半数抑制浓度(IC50)为40.97μg.mL-1;乙酸乙酯萃取物对羟基自由基的清除效果最好,其IC50值为90.5μg.mL-1。牛大力乙醇提取物中石油醚、氯仿、乙酸乙酯萃取物都有很好的抗氧化活性,且稳定性、重复性好。 相似文献
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采用超声波辐照、臭氧氧化以及超声波辐照-臭氧氧化降解废水中的结晶紫;考察了废水初始pH、超声波功率和频率、氧气流量、反应温度等因素对降解效率的影响.结果表明:超声波和臭氧对结晶紫的降解具有协同作用;当废水溶液初始质量浓度为200mg.L-1、pH为10.0时,控制超声波功率和频率分别为100 W和30kHz,氧气流量为0.4L.min-1,反应温度为25℃,反应时间为90 min,则总有机碳(TOC)的去除率可达89.2%,相应的一级反应速率常数为2.38×10-2min-1. 相似文献
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应用响应面法优化了乙醇微波提取板栗花中总黄酮的工艺条件。用光度法在波长510 nm处测定提取液中总黄酮的含量(以芦丁为标准),从而判断提取条件的优劣。经试验确定最优提取条件为:①微波功率700 W;②提取时间80 s;③提取溶剂乙醇与水的体积比为40比60;④板栗花料与提取溶剂的比值为1比100。在此选定条件下板栗花总黄酮的提取率达到(3.47±0.14)g/100 g,与理论值(3.49 g/100 g)很接近。 相似文献
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Fang Wang Shuo Zhang Guowei Deng Kun Xu Haiyan Xu Jialei Liu 《Molecules (Basel, Switzerland)》2022,27(14)
This study aimed to develop an effective technique for extracting total anthocyanins from purple sweet potato (Mianzishu 9) (PSP9) by ultrasound-assisted compound enzymatic extraction (UAEE). Single-factor experiments, Plackett-Burman experimental design, and response surface methodology were utilized for optimizing extraction conditions, and the antioxidant activities were evaluated. Anthocyanins were also measured using an ultra-performance liquid chromatograph linked to a mass spectrometer (UPLC-MS). The maximum yield of total anthocyanins was 2.27 mg/g under the following conditions: the ethanol concentration was 78%, the material-to-liquid ratio was 1:15 g/mL, the enzyme ratio (cellulase: pectinase: papain) was 2:2:1 and its hydrolysis was at 41 °C, pH = 4.5, 1.5 h, the ultrasonication was at 48 °C and conducted twice for 20 min each time. In addition to higher yield, anthocyanins extracted from purple sweet potato by UAEE showed great ability to scavenge DPPH (IC50 of 0.089 μg/mL) and hydroxyl radicals (IC50 of 100.229 μg/mL). Five anthocyanins were found in the purple sweet potato extract from UAEE. Taken together, the ultrasound-assisted compound enzymatic method can rapidly and effectively extract anthocyanins with greater antioxidant capacity from purple sweet potato. 相似文献
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Yuqin Zhang Shiquan Bian Jing Hu Gang Liu Shouhua Peng Hongjiang Chen Zhenying Jiang Tongyong Wang Quan Ye Haibo Zhu 《Molecules (Basel, Switzerland)》2022,27(18)
Natural deep eutectic solvents (NADESs) coupled with microwave-assisted extraction (MAE) were applied to extract total flavonoid compounds from spent sweet potato (Ipomoea batatas L.) leaves. In this study, ten different NADESs were successfully synthesized for the MAE. Based on single-factor experiments, the response surface methodology (RSM) was applied, and the microwave power, extraction temperature, extraction time, and solid–liquid ratio were further evaluated in order to optimize the yields of total flavonoid compounds. Besides, the extracts were recovered by macroporous resin for the biological activity detection of flavonoid compounds. As a result, NADES-2, synthesized by choline chloride and malic acid (molar ratio 1:2), exhibited the highest extraction yield. After that, the NADES-2-based MAE process was optimized and the optimal conditions were as follows: microwave power of 470 W, extraction temperature of 54 °C, extraction time of 21 min, and solid–liquid ratio of 70 mg/mL. The extraction yield (40.21 ± 0.23 mg rutin equivalents/g sweet potato leaves) of the model validation experiment was demonstrated to be in accordance with the predicted value (40.49 mg rutin equivalents/g sweet potato leaves). In addition, flavonoid compounds were efficiently recovered from NADES-extracts with a high recovery yield (>85%) using AB-8 macroporous resin. The bioactivity experiments in vitro confirmed that total flavonoid compounds had good DPPH and O2−· radical-scavenging activity, as well as inhibitory effects on E. coli, S. aureus, E. carotovora, and B. subtilis. In conclusion, this study provides a green and efficient method to extract flavonoid compounds from spent sweet potato leaves, providing technical support for the development and utilization of sweet potato leaves’ waste. 相似文献
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Andrea Torres Lilia G. Noriega Claudia Delgadillo-Puga Armando R. Tovar Arturo Navarro-Ocaa 《Molecules (Basel, Switzerland)》2021,26(2)
Owing to their antioxidant properties, caffeoylquinic acid (CQA)-derivatives could potentially improve the impaired metabolism in hepatic cells, however, their effect on mitochondrial function has not been demonstrated yet. Here, we evaluated the impact of three CQA-derivatives extracted from purple sweet potato, namely 5-CQA, 3,4- and 4,5-diCQA, on mitochondrial activity in primary hepatocytes using an extracellular flux analyzer. Notably, an increase of maximal respiration and spare respiratory capacity were observed when 5-CQA and 3,4-diCQA were added to the system indicating the improved mitochondrial function. Moreover, 3,4-diCQA was shown to considerably increase glycolytic reserve which is a measure of cell capability to respond to an energy demand through glycolysis. Conversely, 4,5-diCQA did not modify mitochondrial activity but increased glycolysis at low concentration in primary hepatocytes. All compounds tested improved cellular capacity to oxidize fatty acids. Overall, our results demonstrated the potential of test CQA-derivatives to modify mitochondrial function in hepatic cells. It is especially relevant in case of dysfunctional mitochondria in hepatocytes linked to hepatic steatosis during obesity, diabetes, and metabolic syndrome. 相似文献
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目的:测定三个品种红薯(黄心红薯、白心红薯、紫红薯)中Cu、 Fe微量元素含量。方法采用V(硝酸)+V(高氯酸)=4+1体系分解样品,火焰原子吸收光谱法( FAAS)测定。结果黄心红薯、白心红薯、紫红薯中Cu、 Fe微量元素均含量丰富,其Cu含量由大到小次序为:紫红薯,黄心红薯,白心红薯, Fe含量的由大到小次序为:黄心红薯,白心红薯,紫红薯。回收率在99.00%~104.00%之间, RSD<2.2%。结论测定结果可为进一步研究红署营养价值与微量元素的关系提供参考。 相似文献
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为建立对红薯粉丝中有害元素铅含量的测定方法,采用微波消解法处理红薯粉丝样品,加入2%NH4H2PO4和0.2%Mg(NO3):混合液作为基体改进剂,用石墨炉原子吸收分光光度法测定了红薯粉丝中铅含量。结果表明,红薯粉丝样品中铅在2.0—40.0ng/mL的范围内吸光度与含量呈良好的线性关系(r=0.9956),平均回收率为98.06%,RSD=1.67%(n=5)。可见该法简单、准确,可作为检测红薯粉丝中铅含量的方法。 相似文献
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叶菜型甘薯茎尖中微量元素和氨基酸的含量分析 总被引:4,自引:0,他引:4
采用等离子体发射光谱法测定了叶菜型甘薯茎尖中K、Ca、Mg、Fe、Zn、Cu、Se等7种微量元素的含量,氨基酸分析仪测定了18种氨基酸的含量。结果表明,与其它12种叶菜类蔬菜相比较,叶菜型甘薯茎尖中K、Ca、Se含量较高;含有18种氨基酸,人体必需的氨基酸种类齐全,含量较高的氨基酸是天冬氨酸、谷氨酸、亮氨酸;高Se是叶菜型甘薯茎尖的显著特点。为探讨叶菜型甘薯茎尖中微量元素和氨基酸与保健功能之间的关系提供了有用的数据。 相似文献
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性信息素;甘薯象鼻虫信息素(E)-2-丁烯酸-(Z)-3-十二烯基酯的全合成 相似文献
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Rong Zhang Chaochen Tang Bingzhi Jiang Xueying Mo Zhangying Wang 《Molecules (Basel, Switzerland)》2021,26(19)
Volatile compounds are the main chemical species determining the characteristic aroma of food. A procedure based on headspace solid-phase microextraction (HP-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) was developed to investigate the volatile compounds of sweet potato. The experimental conditions (fiber coating, incubation temperature and time, extraction time) were optimized for the extraction of volatile compounds from sweet potato. The samples incubated at 80 °C for 30 min and extracted at 80 °C by the fiber with a divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) coating for 30 min gave the most effective extraction of the analytes. The optimized method was applied to study the volatile profile of four sweet potato cultivars (Anna, Jieshu95-16, Ayamursaki, and Shuangzai) with different aroma. In total, 68 compounds were identified and the dominants were aldehydes, followed by alcohols, ketones, and terpenes. Significant differences were observed among the volatile profile of four cultivars. Furthermore, each cultivar was characterized by different compounds with typical flavor. The results substantiated that the optimized HS-SPME GC-MS method could provide an efficient and convenient approach to study the flavor characteristics of sweet potato. This is the basis for studying the key aroma-active compounds and selecting odor-rich accessions, which will help in the targeted improvement of sweet potato flavor in breeding. 相似文献
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Laiquan Shi Yibo Li Lingshang Lin Xiaofeng Bian Cunxu Wei 《Molecules (Basel, Switzerland)》2021,26(23)
Three sweet potato varieties with purple-, yellow-, and white-fleshed root tubers were planted in four growing locations. Starches were isolated from their root tubers, their physicochemical properties (size, iodine absorption, amylose content, crystalline structure, ordered degree, lamellar thickness, swelling power, water solubility, and pasting, thermal and digestion properties) were determined to investigate the effects of variety and growing location on starch properties in sweet potato. The results showed that granule size (D[4,3]) ranged from 12.1 to 18.2 μm, the iodine absorption parameters varied from 0.260 to 0.361 for OD620, from 0.243 to 0.326 for OD680 and from 1.128 to 1.252 for OD620/550, and amylose content varied from 16.4% to 21.2% among starches from three varieties and four growing locations. Starches exhibited C-type X-ray diffraction patterns, and had ordered degrees from 0.634 to 0.726 and lamellar thicknesses from 9.72 to 10.21 nm. Starches had significantly different swelling powers, water solubilities, pasting viscosities, and thermal properties. Native starches had rapidly digestible starch (RDS) from 2.2% to 10.9% and resistant starch (RS) from 58.2% to 89.1%, and gelatinized starches had RDS from 70.5% to 81.4% and RS from 10.8% to 23.3%. Two-way ANOVA analysis showed that starch physicochemical properties were affected significantly by variety, growing location, and their interaction in sweet potato. 相似文献