海藻多酚处理对采后草莓腐烂与贮藏品质的影响

以鼠尾藻为原料提取多酚,研究海藻多酚处理对采后草莓腐烂的控制与贮藏品质的影响。结果表明,鼠尾藻海藻多酚单体组成主要为儿茶素、表儿茶素、儿茶酚、阿魏酸和芦丁,其质量浓度分别为1.95,9.60,43.98,0.63,0.23 mg/mL。总酚质量浓度为16 mg/mL的鼠尾藻提取物可100%抑制草莓灰霉菌(Botrytis cinerea)的生长。新鲜草莓经质量浓度10 mg/mL的海藻多酚处理并于(2±1)℃,90%~95%RH贮藏12 d后,其腐烂率和腐烂指数分别比对照低61.6%和52.5%,草莓硬度、可溶性固形物及VC含量均明显高于对照(p<0.05)。在常温刺伤接种和冷藏不接种Botrytis cinerea 2种条件下,海藻多酚处理的草莓苯丙氨酸解氨酶(PAL)和过氧化物酶(POD)活性均明显高于对照(p<0.05)。结果表明,海藻多酚不但具有直接抗菌活性,可控制草莓的采后腐烂,而且能诱导草莓的采后抗病性,提高抗病相关酶活性,从而降低草莓果实的腐烂,保持草莓品质。

Effects of Phlorotannins Treatment on Fungal Decay and Quality of Harvested Strawberries

In this study,effects of phlorotannins from brown alga Sargassum thunbergii on fungal decay and quality of harvested strawberry(Fragaria ananassa cv Aromas) fruit are investigated.The results show that the phlorotannins composition of brown alga Sargassum thunbergii is catechin,epicatechin,catechol,ferulic acid and rutin,and the contant is 1.95,9.60,43.98,0.63,0.23 mg/mL,respectively.Phlorotannins inhibits the in vitro growth of Botrytis cinerea by 100 % at 16 mg/mL.Decay percentage and decay index in phlorotannins-treated fruit are 61.6 % and 52.5 % lower than that of in control fruit on 12 d after cold storage(2 ℃±1 ℃,90%~95%),respectively.Firmness,soluble solids and VC contents in phlorotannins-treated fruit are higher than those of control(p<0.05).Activities of defense enzymes,including phenylalanine ammonia-lyase(PAL) and peroxidase(POD) in fruit inoculated or non-inoculated with Botrytis cinerea are significantly enhanced by phlorotannins treatment(p<0.05).The results show phlorotannins not only affect the infection of pathogen,but also the defense system and ripening process of harvested fruit.