Screening of active antimicrobial and biological enzymes of microbial isolated from soil in Thailand

Abstract

Objective: The objectives of this study were to isolate microorganisms and screen for potential antimicrobial activities from the soil. Methods:In this study, a total of 425 isolates were isolated from 100 soil samples. The preliminary screening for antimicrobial activities of these isolates was performed by modified cross-streak, agar diffusion, and modified microdilution technique against 16 pathogenic bacteria and fungi. Results:In the anti-microbial activity, there were three isolates, namely, 277, 303, and 307 exhibited inhibitory activity against methicillin-resistant Staphylococcus aureus and Salmonella typhimurium respectively. This study also examined the various enzymes producing from soil microorganisms including chitinase, chitosanase, amylase, cellulose, caseinase, gelatinase, esterase, and lipase production of different selective media for 24 and 48 hrs using the direct spot method. The results revealed that 28 isolates could produce various enzymes with strong activity. Most of them produced gelatinase (5.65%) and caseinase (5.18%). There were four isolates that produce broad-spectrum enzyme. In addition, the investigation of selected microorganism identification showed that they can be divided into three groups: Burkholderia spp., Pseudomonas spp., and Rhodococcus spp. Conclusion:This study demonstrated that the microorganisms from soil are capable of producing potential, antibacterial, and bioactive enzymes.

Biocatalytic potential of Streptomyces spp. isolates from rhizosphere of plants and mycorrhizosphere of fungi

“…Soil microbial diversity is relatively unexplored with respect to enzymes with synthetically useful properties . The rhizosphere represents a unique environment, very crowded in comparison with the bulk soil, which results in high competition for nutrient sources .…”

Determination of Desirable Attributes of an Indigenous Burkholderia Isolate Towards Biological Control of Plant Pathogenic Fungi and Its Microbial Enzyme Production

“…Casein hydrolysis ability of the Burkholderia BSL isolate was determined according to Powthong et al, (2017). Briefl y, the bacterium was heavily inoculated on a Basal Mineral Salts Medium (BMSM) containing skim milk (10 g/L).…”

“…To determine the cellulolytic activity, the Burkholderia BSL isolate was heavily inoculated on the BMSM-containing carboxymethyl cellulose (10 g/L). The cellulose hydrolysis ability of the isolate was noted by checking for the presence or absence of clear halos around the colonies after 7 days of incubation and by fl ooding the culture plate with 0.2% Congo red and de-staining with 1 M NaCl for 15 min (Powthong et al,2017).…”

“…Burkholderia BSL isolate was heavily inoculated on the BMSM medium containing 0.08% chitin azure. The detection of chitinase activity of the isolate was done by checking the presence or absence of clear halos around the bacterial colonies after incubation at room temperature for 7 days (depending on the growth rate of the bacterium) (Powthong et al, 2017).…”

Arthrobacter as Biofactory of Therapeutic Enzymes

“…The information on the application of medically important enzymes produced by the members of the genus Arthrobacter is compiled in this review to explore the future prospects of these therapeutic enzymes as drugs. Soil represents a promising habitat for discovering and isolating new natural products, and only<1% of soil bacterial species are currently known [11]. The Arthrobacter genus is an indigenous flora of soil and usually consists of an important section of the rhizosphere microflora.…”