愛玉子瘦果殘渣水萃物功能性質之研究

Abstract

本研究主要探討愛玉子種子殘渣水萃物(water extract from the residue of jelly fig seeds, WERJFS)之抗氧化活性和WERJFS對食品中毒菌及蔬果軟腐菌的抑制情形等功能性質。 愛玉子種子殘渣以蒸餾水萃取後，收集100%飽和度之硫酸銨沉澱，再以DEAE-Sephacel 陰離子交換樹脂處理，結果顯示果膠酯酶抑制劑(PEI)會與DEAE-Sephacel鍵結而殘留於DEAE-Sephacel管柱中。對此PEI添加過量之polyvinyl polypyrrolidone (PVPP)，添加經熱處理及未經熱處理之胰蛋白酶或牛血清蛋白(BSA) 做實驗，結果顯示愛玉子種子PEI並非單由蛋白質組成。 WERJFS能有效抑制食品中毒菌Escherichia coli O157:H7和Bacillus cereus的生長。在高於150~200 μg/mL的濃度下，WERJFS清除DPPH自由基的能力和還原能力皆比α-tocopherol和BHA強。WERJFS對於亞鐵離子的螯合能力也比檸檬酸佳。至於抗氧化活性、超氧陰離子清除活性和過氧化氫清除活性，WERJFS則明顯比BHA差。以安姆氏試驗發現， WERJFS並無致突變性。 Erwinia 是一種重要的細菌性植物病原菌，廣泛的寄生於植物而造成軟腐。本研究發現，WERJFS能抑制蔬果軟腐菌E. carotovora 和 E. chrysanthemi之生長，以及軟腐菌所分泌之果膠裂解酶(PL)之活性。 綜合言之，WERJFS具有潛力可能發展成為能抑制食品中毒菌和蔬果軟腐菌的安全天然添加物。

The aim of this study is to investigate the functions of water extracts from the residue of jelly fig seeds (WERJFS), including antioxidant activity and the inhibition of food-borne pathogens and bacterial phytopathogens. The residue of jelly fig achenes was extracted with distilled water, precipitated with ammonium sulfate at 100% saturation, and run through a DEAE-Sephacel anion exchange column. The PEI was retained in the column presumably through some kind of molecular interaction. In addition, the result of the addition of excess polyvinyl polypyrrolidone (PVPP), BSA or heated and/or unheated trypsin showed that the PEI is not just a protein. The WERJFS was found to inhibit the growth of Escherichia coli O157:H7 and Bacillus cereus effectively. The DPPH free radical scavenging ability and reduction capacity of WERJFS at a concentration of 150 μg/mL or higher was better than those of α-tocopherol and BHA at the same concentration. The ferrous ion chelating activity of WERJFS was higher than that of citric acid. However, the antioxidant activity, the superoxide anions radical scavenging activity and the hydrogen peroxide scavenging activity of WERJFS were inferior to those of BHA. The WERJFS showed no mutagenicity in the Ames test. The WERJFS was found to inhibit the growth and the PL activity of Erwinia species (BCRC 13137 and BCRC 12613), which are important bacterial phytopathogen to cause soft rot on many plant hosts. In general, WERJFS can be a material to be developed into an additive from natural source to extend the shelf-life of food, to inhibit the growth of foodborne pathogenic bacteria, and to protect plants against bacterial soft rot disease.