2-phenylethanol (rose aroma) production potential of an isolated pichia kudriavzevii through solid-state fermentation

摘要

2-phenylethanol (2-PE) is a higher alcohol widely used in industry that can be obtained by solid-state fermentation (SSF) using low-cost raw materials. This report describes the 2-PE production potential of an indigenous Pichia kudriavzevii isolated from solid-state fermented sugarcane bagasse that possesses attractive characteristics for processing waste streams such as its low-pH tolerance, high growth rate and temperature resistance. Besides, 2-PE production was optimized in batch-SSF using sugarcane bagasse supplemented with L-phenylalanine as substrate. Full factorial design allowed identifying the pH adjustment, micronutrient addition, inoculum and cosubstrate load effects, and response surface methodology served to identify the maximum production based on temperature, initial moisture content (MC0) and specific airflow rate (S-AFR). While the pH adjustment and micronutrient addition did not affect the 2-PE production, temperature and MC0 resulted critical for the process. After optimization, the maximum 2-PE content was 27.2 +/- 0.2 mg per gram of dry substrate at 31 degrees C, 76 % MC0 and 0.129 L h(-1) g(-1) S-AFR. This result was 23.8 % higher than the sub-optimal condition, and it is the highest 2-PE production via SSF reported so far. These results confirm the ability of P. kudriavzevii for producing 2-PE, and its potential for using waste streams as substrate.