EFFECTS OF RUMINAL PROTOZOA ON CELLULOSE DEGRADATION AND THE GROWTH OF AN ANAEROBIC RUMINAL FUNGUS, PIROMYCES SP STRAIN OTS1, IN-VITRO

Citation
Dp. Morgavi et al., EFFECTS OF RUMINAL PROTOZOA ON CELLULOSE DEGRADATION AND THE GROWTH OF AN ANAEROBIC RUMINAL FUNGUS, PIROMYCES SP STRAIN OTS1, IN-VITRO, Applied and environmental microbiology, 60(10), 1994, pp. 3718-3723
Citations number
44
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Microbiology,"Biothechnology & Applied Migrobiology
ISSN journal
0099-2240
Volume
60
Issue
10
Year of publication
1994
Pages
3718 - 3723
Database
ISI
SICI code
0099-2240(1994)60:10<3718:EORPOC>2.0.ZU;2-Y
Abstract
An anaerobic rumen fungus, Piromyces sp. strain OTS1, was incubated in the presence or absence of a mixed, A-type, protozoal population obta ined from a goat, in a medium containing filter paper cellulose as ene rgy source and antibiotics to suppress bacterial growth. Fermentation end products, cellulose degradation, and chitin as an indicator of fun gal biomass were examined. In the presence of protozoa, total volatile fatty acids, notably propionate and butyrate, increased, and lactate decreased. In fungus-protozoan coincubations, formate was not detected at the end of the experiment and the amount of reducing sugars remain ed low throughout the incubation period. The fungal growth in the coin cubations was negatively affected. While protozoal predation on zoospo res was one mechanism of inhibition, mature fungal cells were also aff ected. Total cellulose degradation was greater in fungal monocultures, but the amount of cellulose degraded per unit of fungal biomass was 2 5% larger in the coincubations. The negative effects that the protozoa l predatory activity had on the fungal growth and subsequently on the amount of cellulose degraded by Piromyces sp. strain OTS1 were partial ly attenuated by the protozoal fibrolytic activity or by an enhanced f ungal activity due to a more favorable environment.