Degradation of 3-phenoxybenzoic acid by a filamentous fungus Aspergillus oryzae M-4 strain with self-protection transformation.
A novel filamentous fungus M-4 strain was isolated from soy sauce koji and identified as Aspergillus oryzae (Collection number: CGMCC 11645) on the basis of morphological characteristics and internal transcribed spacer sequence. M-4 could degrade 80.62 % of 3-phenoxybenzoic acid (3-PBA; 100 mg L-1) within 5 days. 3-PBA degradation occurred in accordance with first-order kinetics. The degradation metabolites of 3-PBA were identified through high-performance liquid chromatography-mass spectrometry (HPLC-MS). Relevant enzymatic activities and substrate utilization were also investigated, which indicated that M-4 could effectively degrade the intermediates of 3-PBA. Base on analysis of these metabolites, a novel biochemical pathway for the degradation of 3-PBA was proposed. There exists a mutual transformation between 3-phenoxy-benzyl alcohol and 3-PBA, which was firstly reported about the degradation of 3-PBA and may be attributed to self-protection transformation of M-4; subsequently, 3-PBA was gradually transformed into phenol, 3-hydroxy-5-phenoxy benzoic acid, protocatechuic acid and gallic acid. The safety of M-4 was evaluated via an acute toxicity test in vivo. The biodegradation ability of M-4 without toxic effects reveals that this fungus may be likely to be used for eliminating 3-PBA from contaminated environment or fermented foods.
College of Food Science, Sichuan Agricultural University, Ya'an, Sichuan, 625014, People's Republic of China.
Yuanting
Y
Zhu
College of Food Science, Sichuan Agricultural University, Ya'an, Sichuan, 625014, People's Republic of China.
Jianlong
J
Li
College of Light Industry and Food, Sichuan University, Chengdu, Sichuan, 610065, People's Republic of China.
Kai
K
Yao
College of Food Science, Sichuan Agricultural University, Ya'an, Sichuan, 625014, People's Republic of China.
Nan
N
Zhao
College of Food Science, Sichuan Agricultural University, Ya'an, Sichuan, 625014, People's Republic of China.
Kang
K
Zhou
College of Food Science, Sichuan Agricultural University, Ya'an, Sichuan, 625014, People's Republic of China.
Xinjie
X
Hu
The Laboratory of Microbiology, Dujiangyan Campus, Sichuan Agricultural University, Dujiangyan, Sichuan, 611830, People's Republic of China.
Likou
L
Zou
College of Food Science, Sichuan Agricultural University, Ya'an, Sichuan, 625014, People's Republic of China.
Xinfeng
X
Han
College of Food Science, Sichuan Agricultural University, Ya'an, Sichuan, 625014, People's Republic of China.
Aiping
A
Liu
College of Food Science, Sichuan Agricultural University, Ya'an, Sichuan, 625014, People's Republic of China. lsliang999@163.com.
Shuliang
S
Liu
D001236:Aspergillus oryzae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001565:Benzoates / Q000378:metabolism*; D001711:Biotransformation; D002853:Chromatography, Liquid; D016000:Cluster Analysis; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D005658:Fungi / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D013058:Mass Spectrometry; D053858:Metabolic Networks and Pathways; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D045730:Soy Foods / Q000382:microbiology
D001565:Benzoates; D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer; C017618:3-phenoxybenzoic acid
3-phenoxy-benzyl alcohol; 3-phenoxybenzoic acid; Aspergillus oryzae M-4 strain; Biodegradation; Self-protection; Soy sauce koji