Constituents from leaves of Macaranga hemsleyana

Objective:To study constituents of the leaves of Macaranga hemsleyana,and evaluate their inhibitory effects against NOD-like receptor thermal protein domain associated protein 3(NLRP3)inflammasome activation,and antiproliferative activity.Methods:The constituents were isolated and purified by column chromatography on MCI gel CHP20P/P120,silica gel,Sephadex LH-20,and HPLC.The structures of compounds were determined by 1D,2D NMR,and HR-ESI-MS data.The inhibitory effect of compounds on inflammasome activation was determined by lactate dehydrogenase(LDH)procedure.The antiproliferative activity was evaluated using MTT assay.Results:The study led to the isolation of 23 compounds,including one new compound,identified as(2Z)-3-[4-(β-D-glucopyranosyloxy)-2′-hydroxy-5′-methoxyphenyl]-2-propenoic acid(1),together with 22 known compounds recognized as 1,4-dihydro-4-oxo-3-pyridinecarbonitrile(2),methyl 4-methoxynicotinate(3),4-methoxynicotinonitrile(4),1-(3-O-β-D-glucopyranosyl-4,5-dihydroxyphenyl)-ethanone(5),neoisoastilbin(6),isoastilbin(7),aromadendrin(8),neoastilbin(9),astilbin(10),quercitrin(11),neoschaftoside(12),apigenin 6,8-bis-C-α-L-arabinoside(13),vitexin(14),bergenin(15),scopoletin(16),glucopyranoside salicyl(17),koaburside(18),benzylβ-D-glucoside(19),icariside B5(20),roseoside(21),loliolide(22),and adenosine(23).The tested compounds did not show LDH inhibition nor antiproliferative activity.Conclusion:Compound 1 was a new glycoside.Compounds 2 and 3 were obtained for the first time from natural source.The 22 known compounds constituted of alkaloids(2–4,23),phenolics(5,15,17,18),flavonoids(6–14),coumarin(16),benzyl glycoside(19),and norsesquiterpenes(20–22).All the compounds,1–23,were revealed from M.hemsleyana for the first time.This is the initial uncovering of molecules 1–10,12,13,17–19,and 23 from the genus Macaranga.The isolated compounds,11,14–16,and 20–22 established taxonomic classification of M.hemsleyana in Euphorbiaceae family.Flavonoids were outstanding as chemosystematic markers of Macaranga genus.

海南血桐茎皮脂溶性甾体和三萜类化学成分研究

目的:研究海南血桐茎皮中脂溶性部分的化学成分。方法:采用硅胶柱层析和制备薄层层析等分离纯化技术,对海南血桐茎皮中脂溶性部分进行了分离纯化,得到5种单体化合物。并采用现代波谱法结合理化分析提纯的单体化合物进行结构鉴定。结果:分离得到的单体化合物分别为:β-谷甾醇(1),豆甾-4-烯-3-酮(2),豆甾-4-烯-3,6-二酮(3),3β-O-乙酰油桐酸(4)和海棠果醇(5)。结论:该脂溶性部分主要为甾体和三萜类化合物。

壳聚糖和血桐提取液保鲜槟榔效果研究

[目的]证实血桐提取液对槟榔的保鲜效果。[方法]分别用血桐提取液和壳聚糖溶液处理槟榔,通过储存试验研究两者对槟榔的保鲜效果。[结果]壳聚糖以及壳聚糖与血桐提取液联合保鲜槟榔的效果均好于对照组,但是低于血桐提取液组。采用壳聚糖或血桐提取液涂膜能有效防止水分的蒸发。槟榔汁呈酸性,其pH值在2~3变化。在试验期间,槟榔的pH值先升高后降低,然后再次升高。VC含量总的变化趋势为先升高后降低。血桐提取液浸泡后存放槟榔的VC含量变化最小。血桐提取液浸泡后密封存放的槟榔总糖含量的变化最小,其次是血桐提取液和壳聚糖混合液浸泡后密封存放的槟榔。25 d后,血桐提取液浸泡槟榔的好果率为38%,壳聚糖溶液浸泡槟榔的好果率为23%。[结论]血桐提取液对槟榔的保鲜效果优于壳聚糖溶液。