超声波和溶剂法提取山茱萸中总皂甙的工艺研究

本文通过溶剂法和超声法对山茱萸中总皂甙的提取工艺进行了研究,以提取温度、提取时间、95%乙醇用量等为因素,选用L16(43×26)和L9(34)正交表进行试验。结果表明,超声波的提取效率高于溶剂提取,大大缩短提取时间,优化工艺条件是:提取温度为85℃,提取时间为120min,95%乙醇用量为50ml。在此条件下,总皂甙的提取效率较高,其水解产物人参二醇含量可达5.16mg/g。     

化香树果序中总黄酮不同提取方法对比研究

以化香树果序为原料,对水提醇沉法、乙醇回流提取法、超声提取法等三种方法提取黄酮工艺过程进行了研究,结果表明乙醇回流提取法具有提取率高、操作简便、成本低等特点。并通过响应面实验得到了乙醇回流提取法的最优条件为:温度60℃,提取时间4.5h,提取次数三次,醇浓度70.00%,料液比1:10;黄酮提取率4.25%。     

大孔吸附树脂对虎杖中自藜芦醇吸附性能的研究

本文研究了多种大孔吸附树脂对白藜芦醇的吸附与脱附性能,从中选出H103树脂具有较大吸附量和解吸率.动态吸附实验研究了提取液浓度、pH、流速对H103树脂吸附量的影响,适合的上柱浓度为0.7157mg/ml,上柱液的pH为4.10,上柱液流速为2BV/h.4倍树脂床体积的80%乙醇以1BV/h的流速进行洗脱即可基本将白藜芦醇完全从H103树脂上解吸下来.     

Identifying Wild Versus Cultivated Gene-Alleles Conferring Seed Coat Color and Days to Flowering in Soybean

Annual wild soybean (G. soja) is the ancestor of the cultivated soybean (G. max). To reveal the genetic changes from soja to max, an improved wild soybean chromosome segment substitution line (CSSL) population, SojaCSSLP5, composed of 177 CSSLs with 182 SSR markers (SSR-map), was developed based on SojaCSSLP1 generated from NN1138-2(max)×{"type":"entrez-nucleotide","attrs":{"text":"N24852","term_id":"1139002"}}N24852(soja). The SojaCSSLP5 was genotyped further through whole-genome resequencing, resulting in a physical map with 1366 SNPLDBs (SNP linkage-disequilibrium blocks), which are composed of more markers/segments, shorter marker length and more recombination breakpoints than the SSR-map and caused 721 new wild substituted segments. Using the SNPLDB-map, two loci co-segregating with seed-coat color (SCC) and six loci for days to flowering (DTF) with 88.02% phenotypic contribution were identified. Integrated with parental RNA-seq and DNA-resequencing, two SCC and six DTF candidate genes, including three previously cloned (G, E2 and GmPRR3B) and five newly detected ones, were predicted and verified at nucleotide mutant level, and then demonstrated with the consistency between gene-alleles and their phenotypes in SojaCSSLP5. In total, six of the eight genes were identified with the parental allele-pairs coincided to those in 303 germplasm accessions, then were further demonstrated by the consistency between gene-alleles and germplasm phenotypes. Accordingly, the CSSL population integrated with parental DNA and RNA sequencing data was demonstrated to be an efficient platform in identifying candidate wild vs. cultivated gene-alleles.     

瑞香科植物芫花杀虫有效成分研究

通过水煮沸、热苯萃取、95%乙醇重结晶方法从野生植物芜花中提取到一种黄色结晶，生测实验证明该物质具有良好的杀虫效果，使用柱层析法对这种物质进行再提纯，进而通过UV、NMR及化学方法，证明这种黄色结晶为5，4′-二羟基-7-甲氧基黄酮（芜花素）。     

内部汽化法提取牡荆总黄酮的工艺研究

内部汽化法是一种新的中药提取方法,文章考察了影响内部汽化法提取牡荆总黄酮的主要因素,在单因素实验的基础上,选取解吸剂用量、解吸时间、热提剂用量和热提时间4个因素进行正交实验,最后确定了内部汽化法提取牡荆总黄酮的最优提取工艺,结果表明,最佳工艺为用固液比为1︰7的60%乙醇溶液解吸15 min,再用固液比1︰20的L20%乙醇溶液热提15 min,提取率高达6.75%。     

软枣猕猴桃多糖的体外抗氧化活性

利用水提醇沉法提取软枣猕猴桃粗多糖,经脱蛋白、脱脂,软枣猕猴桃粗多糖的提取率为1.41%。利用DEAE-52纤维素离子交换层析对软枣猕猴桃多糖进行初步分离,得到4种软枣猕猴桃多糖组分。利用SephadexG-200凝胶柱层析对组分Ⅱ和Ⅲ实现了完全分离。通过测定清除自由基能力,评价软枣猕猴桃多糖组分Ⅱ的抗氧化活性。结果表明:软枣猕猴桃多糖对DPPH自由基及烷基自由基(R)有较强的清除能力,IC50值分别为0.497、0.547mg/mL。在受试范围内,随软枣猕猴桃多糖质量浓度的增加,清除能力增强,当软枣猕猴桃多糖质量浓度达到1mg/mL时,其对DPPH自由基及R的清除率分别达到86.4%、87.1%,与VC的清除率相近。软枣猕猴桃多糖对羟自由基(OH)有一定的清除能力,IC50值为0.668mg/mL。其清除能力随多糖质量浓度的增加而有所增加,但其对OH的清除率较VC有一定的差距。软枣猕猴桃多糖对O-2.的清除率较低,清除能力较弱。由此可见,软枣猕猴桃多糖具有较强的抗氧化活性。     

青花椒的热稳定性研究

研究了加热对青花椒的影响.用差热-热重分析(TG-DTA)对青花椒进行了热分析研究.青花椒果皮和青花椒籽的热分解分为几个阶段,其分解特征峰明显.青花椒果皮的特征峰可作为青花椒的辅助鉴别;青花椒的保存使用温度不宜过高.     

杨梅提取物抑制二羰基化合物活性研究

目的 分离纯化杨梅果实提取物并考察不同组分对模型及饼干中甲基乙二醛(methylglyoxal, MGO)、乙二醛(glyoxal, GO)的抑制效果。方法 乙醇浸提制备杨梅果实粗提物(crude extract, CE),采用AB-8大孔吸附树脂,以不同体积分数的乙醇(20%、40%、60%)洗脱,得到三种杨梅提取物;采用NaNO₂- Al(NO₃)₃-NaOH比色法、pH示差法、液相色谱-质谱法测定提取物中花色苷、总黄酮含量和主要成分,并用气相色谱法考察其对模型和曲奇中MGO/GO的抑制活性。结果 40%乙醇组分F₁得率最高,活性最好,主要成分为矢车菊素-3-O-葡萄糖苷(cyanidin-3-O-glucoside, C-3-Glu)和杨梅素-3-O-鼠李糖苷(myricetin-3-O-rhamnoside, M-3-Rha);60%乙醇洗脱组分F₂成分主要为槲皮素-3-O-鼠李糖苷(quercetin-3-O-rhamnoside, Q-3-Rha);当曲奇中提取物添加量为0.4%时,F_1、F₂对MGO和GO均有抑制活性,其中F₁效果最佳,分别为61.5%和40.4%。结论 杨梅果实提取物具有良好清除MGO/GO的能力,为其作为添加剂应用于抑制食品加工中的MGO和GO提供了一定的理论基础。