Analysis of culturable yeast diversity in spontaneously fermented orange wine, orange peel and orangery soil of a Ponkan plantation in China

Abstract

A culturable diversity analysis of yeast species in spontaneous fermentation orange wine, orange peel and orangery soil of a Ponkan plantation in China was followed in this study. A total of 160 isolated yeast strains were identified at the species level through 5.8S-ITS-RFLP and sequence analysis of the 26S rDNA D1/D2 domain. The ten identified species were Barnettozyma californica, Candida humilis, Candida tropicalis, Clavispora lusitaniae, Hanseniaspora occidentalis, Hanseniaspora opuntiae, Hanseniaspora uvarum, Pichia kudriavzevii, Pichia terricola and Torulaspora delbrueckii. Barnettozyma californica and H. occidentalis were the most abundant species in orangery soil. Pichia terricola and H. opuntiae were the prevailing species in orange peel. Additionally, P. kudriavzevii, C. lusitaniae and T. delbrueckii were the dominant species during the beginning, middle and final stages of fermentation, respectively. As a first step in exploring untapped yeast resources of the region, it is important to investigate the yeast microbiota in spontaneous fermentations and screen indigenous yeast which will produce orange wine with regional characteristics.