Actinomycetes are Gram positive bacteria that have been detected in diverse ecological niches. Their member species are known to be a main source of various bioactive compounds. The discovery of Actinomycetes from diverse and unexplored resources has also been linked to increased opportunities to obtain novel bioactive compounds. Insect nest material is being investigated as a new source of novel antimicrobial producing Actinomycetes, which could be harnessed for therapeutic potential. A total of 10 Actinomycetes isolates were collected from the nest of Nasutitermes sp. in Pananjung Pangandaran Nature Reserve. These isolates were evaluated for antimicrobial activity against the challenge bacteria (Eschericia coli, Staphylococcus aureus, Bacillus subtilis, Serratia marcescens) and fungi (Fomitopsis palustris, Fusarium oxysporum, Trichoderma viridae) by dual culture method. The result revealed that several isolates were active against fungi and bacteria. Isolate Pn-TN2 showed the highest level of antibacterial inhibition and the highest antifungal inhibition with Inhibition Rate value more than 80%. By morphological and 16S rRNA gene sequence analysis strongly suggested that the isolate Pn-TN2 belonged to Streptomyces prasinopilosus. We suggested that termite nest is a potential source of bioactive strains of cultivable Actinomycetes for future biotechnological needs. active compounds for further biotechnology application in the medical, pharmaceutical, and agricultural fields.

Spodoptera litura (F.) (Lepidoptera: Noctuidae) is one of the agricultural pests that attacking almost all kinds of herbaceous plants, especiallyvegetables. Insect control using entomopathogenic bacteria is an alternative strategy that is effective and has a lower environmental impact than the use of synthetic insecticides. The purpose of this research was to explore entomopathogenic bacteria that have insecticidal activity against S. litura larvae at various stages of instars. The result showed that 25% of total number of isolated bacteria have potency as entomopathogenic bacteria. Isolate Staphylococcus sciuri strain BLSP-3 and isolate Serratia sp. strain BLSP-4 showed the highest larvicidal activity against the first and second instar larvae of S. litura 83% and 86%, respectively. The activity against on the third instar larvae however was only by 40%. However, the mortality caused by both isolates was lower than that of Bacillus thuringiensis (more than 90% mortality to the first and second instars and 80 % of the third instar larvae). It is suggested that both of isolates are potential to be developed further as a biocontrol agent to control S. litura population.

Entomopathogenic fungi have the potential to infect most arthropods including termites which are economically important major insects pest of wood, wood products and building structures. However, the application of this fungus in the field has not shown satisfactory results yet, one of which is constrained in mass production of conidia. The purpose of this study was to evaluate 16 types of biodegradable products and waste as substrates for mass production of conidia using solid state fermentation method and two types of inoculum namely solid and liquid inoculum. Toxicity tests were carried out on subterranean termites (Coptotermes sp.) based on JIS K 1571, 2010. The parameters observed were the number and dry weight of the conidia produced, conidial viability, nutrient content of the substrate, and percentage of termite mortality. The results showed that rice, sorghum and corn were the best media for the growth of entomopathogenic fungi based on the number of conidia and dry weight of the conidia produced. Metarhizium sp. T4.B23 produced the highest number of conidia, 1.12 x 1011 conidia/100 g substrate and yielded 180.9 ± 0.623 g dry conidia/kg of rice; followed by Metarhizium sp. B2.2 grown on sorghum that resulted in 1.11 x 1010 conidia/100 g substrates and 8 ± 0.570 g /kg sorghum; and B. bassiana produced 8.3 x 109 conidia/100 g substrate and 31.24 ± 0.407 gr/ kg sorghum. Metarhizium sp. B2.2 showed the highest toxicity to termites with 100% mortality was observed within the second day of testing. Therefore the conidia of Metahizium sp. B2.2 is potential to be developed as a biopesticide using rice or sorghum substrate as a carrier.

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Karst regions in Indonesia have the uniqueness of the landscape and biodiversity. The karst is formed by the dissolution of rocks and the precipitation of mineral. In the cave, there are ornaments of stalactite and stalagmite which are formed by the process of mineral precipitation. We have isolated, screened, and identified the soil bacterium from the cave environment (Lysinibacillus macroides). These bacteria are able to precipitate calcium carbonate and can be developed as a self-healing agent concrete. We investigated the proportions and the properties of mixtures concrete containing lightweight aggregate and volcanic ash impregnated with bacteria. A comparison study was made by concrete cylinders subjected to compressive strength tests with and without the bacteria. It found that the strength of concrete with bacteria decreased by less than 10.56% for 28 days of cured specimens. This study showed that the effects of bacteria on the strength of concrete are not considerable. However, these bacteria are effective to repair in the microcrack less than 0.3 mm