In:
Canadian Journal of Microbiology, Canadian Science Publishing, Vol. 56, No. 9 ( 2010-09), p. 707-714
Abstract:
To determine which yeasts are present in the naturally fermented milks of China, 69 samples made by the nomads of Tibet were collected from the Tibetan Plateau in China. From these samples, 225 strains of yeast were isolated and identified using conventional microbiological analysis and gene sequencing analysis of the D1/D2 domain of the large subunit (26S) ribosomal DNA. The results showed that the total concentration of yeasts in these samples ranged from 5.01 to 8.97 log 10 colony-forming units (CFU)/mL (6.91 ± 1.02 log 10 CFU/mL; mean ± SD). The number of cultivable yeasts was higher in the samples from Qinghai (7.55 ± 0.75 log 10 CFU/mL) than those from Tibet (6.21 ± 0.79 log 10 CFU/mL, P 〈 0.05). Moreover, there were 15 phylotypes in these 69 samples. Among these phylotypes, Kluyveromyces marxianus (49.3%, frequency percentage), Saccharomyces cerevisiae (62.3%), and Pichia fermentans (46.4%) appeared frequently and can be considered the most common culturable species in naturally fermented milk products. Traditional fermented Mongolian cow milk featured a wide diversity of yeast species, including Issatchenkia orientalis , Kazachstania unisporus , Rhodotorula mucilaginosa , Candida pararugosa , Torulaspora delbrueckii , Geotrichum sp., Kazachstania unisporus , Geotrichum fragrans , Debaryomyces hansenii , Yarrowia lipolytica , Trichosporon gracile , and Pichia membranifaciens . This study provides new data on yeast composition in naturally fermented milk and shows the yeast biodiversity of fermented milk products from the Tibetan Plateau of China.
Type of Medium:
Online Resource
ISSN:
0008-4166
,
1480-3275
Language:
English
Publisher:
Canadian Science Publishing
Publication Date:
2010
detail.hit.zdb_id:
280534-0
detail.hit.zdb_id:
1481972-7
SSG:
12
