Genome shuffling of Hansenula anomala to improve flavour formation of soy sauce.
Genome shuffling of mutagenized Hansenula anomala was used to improve soy-sauce flavour by enhancing its salt-tolerance, because the concentration of salt was about 17% in high-salt liquid fermentation of soy sauce. A mutant strain H3-8, with stronger resistance to salt, was selected and screened after three rounds of genome shuffling. It was found that H3-8 could grow in YPD media containing a high salt content and within a wide range of pH. In high-salt liquid fermentation, the soy-sauce flavour components produced by H3-8 were distinctly improved compared with the control strains Zygosaccharomyces rouxii and Torulopsis versatilis. Notably, hydroxyethylmethylfuranone produced by H3-8 was 6.3 times as high as that formed by Z. rouxii. Ethyl acetate synthesized by H3-8 was 734 times higher than that yielded by T. versatilis. Another important aroma component, 4-ethylguaiacol was increased by up to 10.84% compared with T. versatilis.
Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Ministry of Education, 300457 Tianjin, China.
Xiaohong
X
Cao
Qian
Q
Song
Chunling
C
Wang
Lihua
L
Hou
D000935:Antifungal Agents / Q000378:metabolism / Q000633:toxicity; D041221:Candida glabrata / Q000254:growth & development / Q000378:metabolism / Q000276:immunology; D002177:Candidiasis / Q000378:metabolism; D032621:DNA Shuffling; D004271:DNA, Fungal / Q000235:genetics; D025141:Drug Resistance, Fungal; D005421:Flavoring Agents / Q000378:metabolism*; D016681:Genome, Fungal; D006863:Hydrogen-Ion Concentration; D060847:Metabolic Engineering / Q000379:methods*; D010843:Pichia / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D012492:Salts / Q000378:metabolism* / Q000633:toxicity; D045730:Soy Foods / Q000382:microbiology*; D020068:Zygosaccharomyces / Q000254:growth & development / Q000378:metabolism
D000935:Antifungal Agents; D004271:DNA, Fungal; D005421:Flavoring Agents; D012492:Salts