Isolation of 4-chlorocinnamic acid from Streptomyces griseocarneus R132, and its inhibition activity against sweet pepper postharvest anthracnose

Streptomyces griseocarneus R132 is an actinobacterium capable of controlling fungi in sweet peppers. The crude S. griseocarneus R132 methanol extract was fractionated in a polystyrene-divinylbenzene column eluted with 20–100% acetone gradient. Compound 1 isolated from the 60% fraction was identified as 4-chlorocinnamic acid. This fraction and 4-chlorocinnamic acid inhibited Colletotrichum gloeosporioides growth by 28% and 65%, respectively, and reduced the diameter of lesions caused by the phytopathogen in Capsicum annuum L. fruits by 33.19% and 31.92%, respectively. The isolated 4-chlorocinnamic acid was not toxic to MRC-5 fibroblasts.灰肉链霉菌R132（Streptomyces griseocarneus R132）是一种能够防治甜椒真菌病害的放线菌（actinobacterium）。对粗提的灰肉链霉菌R132甲醇提取物采用聚苯乙烯-二乙烯基苯色谱柱（polystyrene-divinylbenzene column）进行分级分离，以20%~100%丙酮洗脱梯度（acetone gradient）进行洗脱。从60%洗脱组分中分离得到的化合物1被鉴定为4-氯肉桂酸（4-chlorocinnamic acid）。该组分与4-氯肉桂酸对胶孢炭疽菌（Colletotrichum gloeosporioides）的生长抑制率分别为28%与65%；同时可使该植物病原菌（phytopathogen）在一年生辣椒（Capsicum annuum L.）果实上引发的病斑直径分别降低33.19%与31.92%。分离得到的4-氯肉桂酸对MRC-5成纤维细胞（fibroblasts）无细胞毒性。