Application of Phenol Pretreatment for the Isolation of Rare Actinomycetes from Indonesian Soil

Abstract

Phenol treatment was applied for isolation of rare Actinomycetes using 25 soil samples collected from Pulau Seribu, Tanjung Redep, Manokwari, and Halmahera. The samples were air-dried and suspended in 1.5 % (w/v) phenol solution at 30 oC for 30 minutes, and subsequently cultured on plates of humic acid-vitamin agar (HVA) medium supplemented with cycloheximide (50 μg/mL) and nystatin (50 μg/mL). A total of 61 isolates were obtained and the most dominant isolates were not Streptomyces (only 24.6%), whereas other genera such as Micromonospora, Actinomadura, Microbispora and Polymorphospora were isolated with ratios of 49.2%, 13.1%, 9.8%, and 3.3%, respectively

Bacterial microbiome in tropical lichens and the effect of the isolation method on culturable lichen-derived actinobacteria

“…Even though the growth rate of actinobacteria is slow, the usual colony morphology was simple due to the color difference between the colonies and the black color of the medium. Humic acid activation of spore germination was thought to be one of the factors that caused an increase in the variety of actinobacterial colonies on the medium 56 . Furthermore, the colonization of actinobacteria on isolation media was prevented by the dominance of other microorganisms.…”

SELECTIVE ISOLATION OF Dactylosporangium AND Micromonospora FROM THE SOIL OF KARST CAVE OF SIMEULUE ISLAND AND THEIR ANTIBACTERIAL POTENCY

“…This pretreatment has been previously used to select genus Dactylosporangium from soil (Chiaraphongphon et al, 2010;Thawai et al, 2011;Thawa and Suriyachadkun, 2013) and genus Micromonaspora (Hayakawa et al, 1991). It also has been used to reduce the number of Streptomyces colonies on HV agar plates and could be beneficial to obtain other rare actinomycetes (Istianto et al, 2012). This method was also successfully used to explore the actinomycetes from tropical limestone caves and Thai coastal marine sediment (Niyomvong et al, 2012;Ruttanasutja and Pathom-Aree, 2015).…”

Characterization of Actinobacterial Communities from Arauca River Sediments (Colombia) Reveals Antimicrobial Potential Presented in Low Abundant Isolates

“…The isolates demonstrating activity against at least one microbe were derived mainly from the phenol, sonication and microwave pretreatments Table 2 . It has been established that phenol can cause a leakage of cellular contents by first injuring lipid-containing membranes and then producing hydrogen bonding with vital proteins such as microbial enzymes [ 54 ]. On the other hand, bubbles formed through the cavitation process during sonication pretreatments can generate pressure which leads to breaking of the cell wall in microorganisms [ 55 ].…”

“…Finally, molecules such as water, DNA and proteins, respond to non-ionizing waves (microwaves) producing friction with neighboring molecules resulting in vibration and cellular damage [ 27 ]. Although these three physicochemical pretreatments have been used previously, they serve as a powerful tool for actinobacteria isolation due to their capacity to inhibit the growth of other taxa of microorganisms without producing lethal damage to actinobacteria [ 54 ]. It is possible that resistance to such treatments could be associated with a singular feature of these actinobacteria making them capable of producing different responses against an array of harsh condition.…”