中文摘要：

在生物活性指导下,从一株来源于药用红树尖瓣海莲的内生真菌Penicillium sp.（J41221）中分离鉴定了6个化合物,包括4个四环三萜类化合物和2个甾醇类化合物,结构分别为：11-羰基-12α-乙酰氧基-4,4-二甲基-24-甲烯基-5α-胆甾-8,14-二烯-2α,3β-二醇（1）,12α-乙酰氧基-4,4-二甲基-24-甲烯基-5α-胆甾-8-单烯-3β,11β-二醇（2）,12α-乙酰氧基-4,4-二甲基-24-甲烯基-5α-胆甾-8,14-二烯-3β,11β-二醇（3）,12α-乙酰氧基-4,4-二甲基-24-甲烯基-5α-胆甾-8,14-二烯-2α,3β,11β-三醇（4）,啤酒甾醇（5）和（3β,5α,6β,22E）-6-甲氧基麦角甾-7,22-二烯-3,5-二醇（6）.其中化合物1为首次从生物中获得,且1和2的波谱数据迄今未见任何报道.抗菌活性结果表明,化合物2和4对金黄色葡萄球菌、大肠杆菌和四联球菌均显示一定的抑制活性,最小抑菌浓度（MIC）分别为5和4.86μmol/L.

英文摘要：

Under the guidance of bioassay, four tetracyclic triterpenoids and two steroids were isolated from the fermentation products of Penicillium sp.（J41221）, a fungus obtained from a mangrove Bruguiera sexangula var. Rhynchopetala. Their structures were identified as 11-oxo-12α-acetoxy-4,4-dimethyl-24-methylene-5α-cholesta-8,14-diene-2α,3β-diol（1）, 12α- acetoxy-4,4-dimethyl-24-methylene-5α-cholesta-8-momoene-3β,11β-diol（2）, 12α-acetoxy-4,4-dimethyl-24-methylene-5α-cholesta-8,14-diene-3β,11β-diol（3）, 12α-acetoxy-4,4-dimethyl-24-methylene-5α-cholesta-8,14-diene-2α,3β,11β-triol（4）, cerevisterol（5） and（3β,5α,6β,22E）-6-methoxyergosta-7,22-diene-3,5-diol（6）. Among them, compound 1 was a new naturally occurring compound, and 1 and 2 have no spectroscopic data reported until now. Compounds 2 and 4 showed inhibitory activities against Staphylococcus aureus, Escherichia coli and Micrococcus tetragenu, with minimum inhibitory concentration（MIC）values of 5 and 4.86 μmol/L, respectively.