ABSTRACT
A bacterium Stenotrophomonas sp. TRMK2 capable of utilizing cinnamic acid was isolated from agro-industrial waste by enrichment culture technique. This strain completely utilizes 5 mM cinnamic acid within 18 h of incubation. The different metabolites formed during the degradation of cinnamic acid were characterized by GC-HRMS. The involvement of various enzymes, namely cinnamate reductase, 3-phenylpropionic acid hydroxylase, p-hydroxybenzoic acid hydroxylase and protocatechuate 3,4-dioxygenase in cinnamic acid degradation was demonstrated. A catabolic pathway for cinnamic acid in Stenotrophomonas sp. TRMK2 is as follows: Cinnamic acid; 3-Phenylpropionic acid; 3-(4-Hydroxyphenyl) propionic acid; 4-Hydroxy benzoic acid and Protocatechuic acid. Further, this strain is capable of utilizing various phenolic compounds.
ABSTRACT
Three bacterial strains; Pseudomonas sp. TRMK1, Stenotrophomonas sp. TRMK2 and Xanthomonas sp. TRMK3 were isolated from agro-industrial waste by enrichment culture technique that are capable of utilizing phenolic acids as sole source of carbon and energy. These strains were found to utilize p-coumaric, ferulic and caffeic acid. The individual strains utilized 5 mM of mixed phenolic acids within 20 h of incubation. The bacterial consortium composing these strains was prepared and studied the efficient degradation of phenolic compounds. The bacterial consortium showed the enhanced utilization of 30 mM individual and 25 mM mixed phenolic acids within 32 and 40 h of incubation, respectively. The degradation efficiency of these strains in all the above experiments was above 90%. The prepared bacterial consortium serves as a suitable method for the in situ application of sites contaminated with wide range of phenolic compounds.