Search

Actinobacteria are an important and interesting group of Gram-positive bacteria. Although rare, they are regular members of ruminal microbes. However, there is a significant lack of information on the existence and biology of rumen actinobacteria. Therefore, this study aimed to isolate unknown actinomycetes from ruminal fluid and characterize them for bioprospection. Twenty-six strains were isolated and analyzed for biological activity using direct serial dilution on humic acid vitamin agar. Seventeen isolates have been identified and belong to the genus Streptomyces. Of these 26 strains, 16 exhibited antibiotic activity against Staphylococcus aureus InaCC B-4 and 12 against Escherichia coli InaCC InaCC B-5. Enzymatic screening assays showed that the rumen actinobacteria isolates possessed protease, amylase, lipase, and cellulase enzymatic activities. A total of 18 isolates (69.5%) of rumen actinobacteria could produce protease enzymes, 13 isolates (56.52%) could produce amylase enzymes, and 12 isolates (52.17%) were capable of producing lipase enzymes, and 11 isolates (47.82%) had the potential to produce cellulase enzymes. In conclusion, the present study demonstrated that actinobacteria exhibiting bioactive compounds had been isolated from bovine rumen fluid. In addition, antibacterial compounds active against the pathogens S. aureus InaCC B-4 and E. coli InaCC B-5 and several industrially important enzyme producers have also been demonstrated in this study. These findings may be necessary to produce potentially new antibiotics and enzymes from actinobacteria indigenous to Indonesia. [ABSTRACT FROM AUTHOR]

Marine sponges are known as the producers of marine-derived bioactive compounds. Among all, sponges from Indonesia were reported as the second-highest contributors to many new sponge-derived compounds. A recent review on the bioactive potential of Indonesian sponges reported the potential of sponges from Indonesia to produce bioactive compounds, including alkaloids, terpenoids, peptides, macrolides, and polyketides. In addition to their ability to produce bioactive compounds, sponges harbor many different prokaryotic phyla, including Proteobacteria, Actinobacteria, and Cyanobacteria. Many reports have indicated the bioactive potential of Indonesian sponges. However, research on bioprospecting bacteria associated with Indonesian sponges remains limited and under-explored. The present study reviewed available reports on the diversity of bacteria associated with Indonesian sponges, including their bioactive potential. Available reports from 2011 to 2021 were collected, aiming to provide a general overview of bioprospecting sponge-associated bacteria in Indonesia. The bioactive potential of compounds derived from bacteria associated with Indonesian sponges was analyzed, for example for antimicrobial and anticancer. In addition to the review, the present study also discusses the opportunity and challenge of conducting marine bioprospecting, especially for bioprospecting sponge-associated bacteria. [ABSTRACT FROM AUTHOR]