Study of polygalacturonase production by an Antarctic yeast and obtention of dragon fruit juice by maceration at mild temperature  

作　　者：Brenda Bezus Juan Carlos Contreras Esquivel Sebastian Cavalitto Ivana Cavello 

机构地区：[1]Centro de Investigacion y Desarrollo en Fermentaciones Industriales(CINDEFI,UNLP,CCT-La Plata,CONICET),Calle 47 y 115,B1900ASH,La Plata,Provincia de Buenos Aires,Argentina [2]Laboratory of Applied Glycobiotechnology,Academic Group of Food Science and Technology,School of Chemistry,Universidad Autonoma de Coahuila,Unidad Saltillo,Saltillo,2528,Coahuila,Mexico

出　　处：《Food Bioscience》2022年第5期893-903,共11页食品生物科学（英文）

基　　金：supported by grants from the National Scientific and Technological Research Council and the National Agency for the Promotion of Science and Technology(ANPCyT,PICT 2018-3194 and PICT 2019-3123).

摘　　要：The objectives of the present survey were to study the production and the biochemical characterization of an enzymatic cold-active extract with polygalacturonase activity,to perform a first insight into its possible application in fruit-juice obtention process,and to use this juice for food products preparation.The enzymatic extract was produced by the Antarctic yeast Mrakia sp.LP January 7,2016 in a bioreactor with citric pectin as substrate.The polygalacturonase activity showed optimum conditions for reaction at 45◦C and pH 5.0.This activity was stable until 40◦C but deactivated at higher temperatures.Inhibition by Hg+2 suggested the presence of a thiol-dependent enzyme.A high-molecular polygalacturonase was detected in an SDS-PAGE and zymography analysis.Reaction-products were observed by thin-layer chromatography and suggested the endo-mode of action.The enzymatic extract had some accessory enzymes,such as pectin methylesterase,β-glucosidase,cellulase and inulinase.As a first insight into the potential use of this enzymatic extract for fruit maceration at mild temperatures,red and white dragon fruits were selected as models.At 23◦C,juice yields of 15%-23%higher than control were obtained after treatments,with a decrease of remanent solid of 25%-35%.The color of red dragon fruit juice increased with enzymatic treatment.Alginate balls that were prepared with the juices demonstrated a hardness of~10 N.The compression force of low-calorie sugar gels was 3.8 N.This work provided a complete study of the production,characterization,application and food product production using a new cold-active polygalacturonase extract of Antarctic origin.

关 键 词：Antarctic enzymes Cold active pectinases Mrakia sp Hylocereus monacanthus Hylocereus undatus 

分 类 号：TS255.4[轻工技术与工程—农产品加工及贮藏工程]