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Because colony formation is essential to seek bacterial functions by the direct observation of phenotype, the diversification of colony formation for culturable bacteria is a big challenge in the research field of Environmental Biotechnology. In this study, the biodiversity of cultivable bacteria (colony or liquid culture) was compared by using Luria-Bertani (LB) medium and waste sewage sludge (WSS) under different dilutions and temperatures. When WSS was used as a bacterial source, whereas the highest number of colonies was found at the concentration of WSS (5%), a particular concentration of LB (10%) or WSS (1%) as a growth medium showed the best number of the operational taxonomic units (OTUs) of colonies. The results of bacterial community structure indicated that there are 1, 8, and 12 bacterial genera found uniquely in the agar plates of LB, 10% LB, and 5% WSS. By contrast, when palm oil mill effluent sludge was used as a bacterial source, the effect of dilution was different with WSS. When comparing the biodiversity between colonies and liquid culture, a high OTU value was observed in the colonies on the plate. In addition, 30°C showed the highest number of colonies in LB, 10% LB, and 5% WSS whereas the best OTUs were observed at 37°C for LB and 10% LB, and at 25°C for 5% WSS. This study demonstrates the diversification of cultivable bacteria through the number of OTUs in diluted LB medium and WSS, which is beneficial to isolate a unique bacterial strain. Key points • Impacts of diluted LB medium and WSS for colony formation were determined. • Difference of concentration of LB and WSS made different effects on colony formation. • Temperature change affected on diluted LB and WSS as media.

Fermented jackfruit (Artocarpus heterophyllus) extracts were produced using pure symbiotic culture of bacteria and yeast (SCOBY) under controlled fermentation process. Both female and male Sprague‐Dawley rats were orally administrated with 4,000 mg/kg of fermented jackfruit pulp and leaves extracts for 28 consecutive days. Body weight of rats was recorded at 1‐week interval until necropsy day. There was no mortality reported along the experiment with no significant differences (p > .05) record among organ histopathology and blood biochemical parameters in treated groups when compared to control group. Interestingly, there were significant differences (p, No toxicity symptoms were observed in Sprague‐Dawley rats for both sexes after 28 days oral administration with fermented jackfruit pulp and leaves. There were significant differences (p

The jackfruit (Artocarpus heterophyllus L.) is one of the Southeast Asia’s popular tropical fruit trees...

Herein, we prepared and characterized two antimicrobial cyclic peptides immobilized on reduced graphene oxide (rGO) and accessed their anti-bacterial towards Gram-negative (Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus) bacterias. The covalent interaction between the tyrosine and histidine based cyclic peptides and the rGO occurred via the carboxylic groups of the reduced graphene and the amino side chain groups of the cyclic peptides. A selective antibacterial effect is observed for the cyclic peptides functionalized rGO. The inhibition zone test showed that both the tyrosine and histidine cyclic based peptide immobilized on rGO exhibited higher anti-bacterial potency towards the bacteria in comparison to bare rGO which can be attributed to the synergistic effect of the antimicrobial peptide and rGO.