SYNTHESIS OF PHENYLALANINE AND PRODUCTION OF OTHER RELATED-COMPOUNDS FROM PHENYLPYRUVIC ACID AND PHENYLACETIC ACID BY RUMINAL BACTERIA, PROTOZOA, AND THEIR MIXTURE IN-VITRO

Authors
Citation
Mr. Amin et R. Onodera, SYNTHESIS OF PHENYLALANINE AND PRODUCTION OF OTHER RELATED-COMPOUNDS FROM PHENYLPYRUVIC ACID AND PHENYLACETIC ACID BY RUMINAL BACTERIA, PROTOZOA, AND THEIR MIXTURE IN-VITRO, Journal of General and Applied Microbiology, 43(1), 1997, pp. 9-15
Citations number
32
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Microbiology,"Biothechnology & Applied Migrobiology
ISSN journal
0022-1260
Volume
43
Issue
1
Year of publication
1997
Pages
9 - 15
Database
ISI
SICI code
0022-1260(1997)43:1<9:SOPAPO>2.0.ZU;2-W
Abstract
Phenylalanine (Phe) synthesis and the production of other related comp ounds by mixed ruminal bacteria (B), protozoa (P), and a combination o f the two mixture (BP) in an in vitro system were quantitatively inves tigated using phenylpyruvic acid (PPY) and phenylacetic acid (PAA) as substrates. Rumen microorganisms were collected from fistulated goats fed lucerne cubes (Medicago sativa) and a concentrated mixture twice a day. Microbial suspensions were anaerobically incubated at 39 degrees C for 12 h. Phe and some other related compounds in both supernatants and microbial hydrolysates of the incubations were analysed by HPLC, A large quantity of Phe was produced from both PPY and PAA not only in a but also in P. In B suspensions, free Phe also accumulated in the m edium only when PPY was used as a substrate. The ability of B to synth esize Phe from both PPY and PAA (expressed as unit 'per microbial nitr ogen') was 5.1 and 24.8% higher than P, respectively. Phe production f rom PPY in a and P was 43.5 and 55.2% higher than that from PAA. Large amounts of PAA (17-27%) were produced from PPY in all microbial suspe nsion and production amounts were similar in a and P. Small amounts of benzoic acid (BZA) were produced from PPY and PAA in a, P,and BP, and higher BZA production was observed in P as compared to a, Phenylpropi onic acid (PPR) was produced in a from both PPY and PAA, but not in P or BP, A trace amount of phenyllactic acid (PLA) was detected only fro m PPY in a. Higher concentrations of an unknown compound from PPY and PAA were found to be accumulated in the body protein of a and also in the medium of P, and production of the compound from both PPY and PAA was also higher in a than P.