Abstract:
Water samples from the surface waters of Balabagon Boiling
Lake in Manito, Albay in December 2002 were passed through a
membrane filtration device with membranes with 0.45 pm pore size.
The membranes were placed in TGYE plates and incubated at 50°C
for 48 hours. The isolates were purified and subjected to various
morphological and physiological tests for the purposes of
presumptive identification. A total of fifty-two heterotrophic
bacterial strains were isolated. They were found to be thermophilic
and/or thermotolerant strains of Bacillus species, namely Bacillus
acidocaldarius, B. brevis, B. circulans, B. coagulans, B.
laterosporus, B. Hcheniforniis, B pumilits, B. sphaericus, B.
stearothermophilus, and B. subtilis
The ubiquity of Bacillus species is attributed to its
endospores, which are heat-resistant, disperse easily, and are able to
survive in extreme conditions. The proximity of the sampling to the
shoreline may account for the identified Bacillus species commonly
of soil origins. The absence of other probable organisms may be due
to limiting factors in the collection and cultivation procedures.