美国豆芋花总皂苷制备及其α-葡萄糖苷酶抑制活性

为高效利用美国豆芋花皂苷类化合物,以皂苷得率和纯度为指标,研究美国豆芋花总皂苷的提取工艺及大孔树脂纯化工艺,并对制备的美国豆芋花总皂苷的抗氧化及α-葡萄糖苷酶活性抑制能力进行研究。结果表明,美国豆芋花总皂苷的提取工艺为提取溶剂90%乙醇,料液比1∶20,温度70℃,提取时间2 h。得到的提取物石油醚脱脂后用水饱和正丁醇萃取,D-101大孔树脂吸附柱纯化的工艺为上样皂苷质量浓度1 mg·m L~(-1),上样量40 m L·g~(-1)树脂,洗脱剂为80%乙醇(pH值6),洗脱剂用量4 BV(树脂柱体积)。制备的美国豆芋花总皂苷样得率4.24%,纯度达65.35%,比粗提物(纯度15.27%)提高了约3倍;抗氧化性能(清除DPPH和ABTS自由基IC50值分别为51.08、29.24μg·m L~(-1))和α-葡萄糖苷酶活性抑制能力(IC50值为83.62μg·m L~(-1))也均优于粗提物(清除DPPH、ABTS自由基IC50值分别为286.51、69.92μg·m L~(-1),α-葡萄糖苷酶的抑制浓度(IC50)值为1 043.57μg·m L~(-1)),表明该工艺可用于高活性美国豆芋花总皂苷的富集和纯化。此外,美国豆芋花总皂苷抑制α-葡萄糖苷酶活性的抑制类型为竞争型抑制,抑制常数为49.68μg·m L~(-1)。本研究结果为开发具有降血糖功能的医药中间体或功能性食品提供了新资源和实践基础。     

灵芝三萜高产菌株原生质体紫外诱变选育

对灵芝（Ganoderma lucidum）HG菌株进行原生质体紫外诱变处理,经过初筛和复筛,获得了生长速度、菌丝干重和三萜含量明显高于出发菌株的9株诱变株;通过10次PDA斜面继代培养、液体培养以及栽培试验筛选,获得了菌丝干重和三萜含量稳定提高的诱变株UV-3,该菌株在栽培袋中的菌丝生长速率及子实体中三萜含量分别比出发菌株高58．6％和29．4％。SRAP-PCR结果表明,诱变株UV-3与出发菌株相比,DNA指纹图谱发生了明显改变。     

灵芝主要有效成分超声提取工艺的优化

目的研究灵芝三萜和灵芝多糖的超声提取工艺．方法采用超声波辅助法,探讨了提取剂的pH（碱醇）、提取剂用量、提取温度、超声时间4个因素对灵芝三萜提取效果的影响,并用无水乙醇做对照实验．探讨超声时间、提取温度、提取剂用量3个因素对灵芝多糖提取效果的影响．结果醇的pH和超声时间对灵芝三萜的提取效果有明显影响,其他两因素影响效果不大;提取时间和提取温度两个因素对灵芝多糖提取效果达到极显著水平．结论灵芝三萜最佳提取条件为：乙醇用量30倍＋提取温度60℃＋提取时间60min＋碱醇pH8．5,对无水乙醇调pH可以明显提高乙醇提取灵芝三萜的能力;灵芝多糖提取最佳条件为：超声提取时间55min＋提取温度55℃＋提取剂用量50倍．     

Crude Polysaccharide and Triterpene Content of Ganoderma Fruit Bodies at Different Stages of Development

Crude polysaccharide and triterpene levels were determined in the fruit bodies of eleven Lingzhi samples,designated as Ganoderma lucidum,G.capense and G.tsugae,harvested at four different stages of development: budding,elongation,maturation and senescence.In most cases,crude polysaccharide levels were highest at the budding stage,decreased during the elongation stage,increased again at maturation and were lowest at senescence.Triterpene levels generally remained relatively high during the first three develo...     

茶枝屑代料栽培对灵芝生物转化率和质量的影响

添加不同用量的茶枝屑进行灵芝的代料栽培,并分析灵芝的生物转化率和灵芝多糖和总三萜的含量.结果表明:灵芝在茶枝屑代料培养基上能正常生长、出芝,产生和释放孢子,灵芝的生物转化率比杂木屑代料栽培降低了6.25％～31.33％,灵芝多糖含量高3.03％～28.28％,灵芝总三萜含量高2.62％～17.40％.认为茶枝屑可以作为...     

高效液相色谱法测定白桦树皮中白桦酯醇的含量

为了提取白桦三萜炎物质，建立了高效液相色谱法测定白桦(Betula platyphylla Suk．)树皮中白桦酯醇含量的方法、色谱柱为ODS C18；流动相为甲醇：水(88：12)，紫外检测波长为210nm，柱温30℃；柱压6．4MPa，流速1mL／min，白桦酯醇的线性范围为15．0～300．0μg，平均回收率为93.93％。对同一样品重复测定5次，相对标准偏差为0．36％，与比色法和气相色谱法相比，本法更准确、简便。     

Good Practices in Sponge Natural Product Studies: Revising Vouchers with Isomalabaricane Triterpenes

Species misidentification in the field of natural products is an acknowledged problem. These errors are especially widespread in sponge studies, albeit rarely assessed and documented. As a case study, we aim to revisit reports of isomalabaricane triterpenes, isolated from four demosponge genera: Jaspis, Geodia, Stelletta and Rhabdastrella. From a total of 44 articles (1981–2022), 27 unique vouchers were listed, 21 of which were accessed and re-examined here: 11 (52.4%) of these were misidentified. Overall, 65.9% of the studies published an incorrect species name: previously identified Jaspis and Stelletta species were all in fact Rhabdastrella globostellata. We conclude that isomalabaricane triterpenes were isolated from only two Rhabdastrella species and possibly one Geodia species. In addition to shedding a new light on the distribution of isomalabaricane triterpenes, this study is an opportunity to highlight the crucial importance of vouchers in natural product studies. Doing so, we discuss the impact of species misidentification and poor accessibility of vouchers in the field of sponge natural products. We advocate for stricter voucher guidelines in natural product journals and propose a common protocol of good practice, in the hope of reducing misidentifications in sponge studies, ensure reproducibility of studies, and facilitate follow-up work on the original material.     

木质素对灵芝菌丝体生长的影响

为了解添加外源木质素对灵芝菌丝体生长的影响,该研究通过在灵芝培养基中添加纤维素、半纤维素和木质素,考察了外源添加木质纤维素主要组分对灵芝菌体生长的影响,发现木质素添加明显促进灵芝菌丝体生长;进一步考察添加不同浓度木质素灵芝菌丝体生长情况以及灵芝产多糖、三萜变化规律。结果表明少量添加木质素对灵芝菌丝体生长有明显促进作用,木质素加量为1.0%时,灵芝菌丝体生长情况最好,生物量比对照提高了56%,同时灵芝胞外多糖、胞内多糖及灵芝胞外三萜、胞内三萜的合成均有明显提高,其中胞内多糖提高43%;4种灵芝菌株发酵产多糖、三萜结果对比分析表明1.0%木质素添加均能提高不同菌株发酵多糖、三萜含量,木质素作为营养基质在不同灵芝菌株培养过程中添加均能促进菌丝体活性物质合成。研究结果可为灵芝菌生长代谢研究及人工栽培提供科学依据和参考。     

灵芝菌丝体及发酵液中三萜化合物的研究进展

三萜类化合物是灵芝(Ganoderma lucidum)的关键药效成分之一.笔者综述灵芝菌丝体及发酵液中三萜化合物的主要组分、深层发酵技术和合成关键酶、抗肿瘤作用及其构效关系.     

不同日常食用加工方法对灵芝中活性成分利用的比较

为阐明日常的食用加工方法是否能充分利用灵芝(Ganoderma lingzhi)中的活性成分,用苯酚硫酸法和HPLC法分别检测龙芝二号子实体片经水煮、焖烧、水泡、酒浸四种加工处理的提取液中灵芝多糖和灵芝三萜含量,结果水煮、焖烧、水泡40min后多糖基本全部溶出,三萜溶出率分别为85.5%、83.1%、51.1%;50%的白酒浸泡7d后三萜溶出率为95.0%,而多糖溶出率仅为0.31%;用这些方法比较龙芝二号与菌草灵芝的处理结果,结果多糖和三萜溶出效果基本相同;通过比较,焖烧40min能使灵芝片中有效成分大部分溶出。