Antioxidant Activities of Streptomyces sp. strain MUSC 14 from Mangrove Forest Soil in Malaysia

Abstract

The mangrove ecosystem of Malaysia remains yet to be fully explored for potential microbes that produce biologically active metabolites. In the present study, a mangrove-derived Streptomyces sp. strain MUSC 14 previously isolated from the state of Pahang, Malaysia Peninsula, was studied for its potential in producing antioxidant metabolites. The identity of Streptomyces sp. strain MUSC14 was consistent with the genotypic and phenotypic characteristics of the Streptomyces genus. The antioxidant potential of Streptomyces sp. strain MUSC 14 was determined through screening of its methanolic extract against sets of antioxidant assays. The results were indicative of Streptomyces sp. strain MUSC 14 displaying strong antioxidant activity against ABTS, DPPH free radicals and metal chelating activity of 62.71 ± 3.30%, 24.71 ± 2.22%, and 55.82 ± 2.35%, respectively. The result of ferric reducing activity measured in terms of dose was equivalent to 2.35–2.45 μg of positive control ascorbic acid. Furthermore, there was a high correlation between the total phenolic content and the antioxidant activities with r = 0.979, r = 0.858, and r = 0.983 representing ABTS, DPPH, and metal chelation, respectively. Overall, the present study suggests that Streptomyces sp. strain MUSC 14 from mangrove forest soil has potential to produce antioxidant metabolites that can be further exploited for therapeutic application.

Streptomyces sp. Strain MUSC 125 from Mangrove Soil in Malaysia with Anti-MRSA, Anti-Biofilm and Antioxidant Activities

“…In addition to ABTS, DPPH and metal chelating antioxidant methods, the FRAP antioxidant assay was also conducted. In the FRAP experiment, the Fe 3+ and the methanolic extract MUSC 125 participate in a redox reaction which resulted in the Fe 3+ being reduced to Fe 2+ [29]. The reduced potassium ferrous cyanide was afterwards allowed to react with ferric chloride forming a dark blue complex which has an absorbance wavelength at about 700 nm [29].…”

“…In the FRAP experiment, the Fe 3+ and the methanolic extract MUSC 125 participate in a redox reaction which resulted in the Fe 3+ being reduced to Fe 2+ [29]. The reduced potassium ferrous cyanide was afterwards allowed to react with ferric chloride forming a dark blue complex which has an absorbance wavelength at about 700 nm [29]. Based on the current FRAP experiment, the absorbance (p < 0.05) of methanolic extract MUSC 125 ranged from 1.53 ± 0.06 to 1.55 ± 0.05 in the dose range of 1-2 mg which was equivalent to 0.22-0.23 µg of ascorbic acid ( Figure S4).…”

“…The TPC test using Folin-Ciocalteu's reagent was performed to determine the presence of phenolic compounds in the methanolic extract MUSC 125. In the presence of a reducing agent, the yellow Folin-Ciocalteu's reagent will be reduced, indicated by the change in colour of the solution to dark blue [29]. The visible colour change suggested the presence of phenolic compounds with the strongest blue colour at 4 mg/mL of the methanolic extract MUSC 125.…”

“…It is not surprising to find Streptomyces from stressful ecosystem such as mangrove forest, produces secondary metabolites to assist in the defence mechanisms, particularly antioxidants are used to prevent oxidative damage. The antioxidant potential of several mangrove Streptomyces in Malaysia have been reported [27][28][29]. To date, the mangrove forest remains largely an understudied ecosystem with respect to investigating their secondary metabolites which are valuable sources for future development of therapeutics [24].…”

Comprehensive Insight of Neurodegenerative Diseases and The Role of Neurotoxin Agents — Glutamate

“…Studies demonstrated that radical scavengers like vitamin E, in the form of tocopherol and tocotrienol, can protect the glutamate-injured cells from oxidative stress. Other than vitamin E, other sources such as microbial resources were also demonstrating strong antioxidants [116][117][118][119][120][121][122][123][124][125][126] and neuroprotective properties [127][128][129][130][131][132] such as metal chelating and radical scavenging potentials [133][134][135][136][137][138][139][140] . In conclusion, neuronal cell seemed to be the most vulnerable brain cells toward glutamate toxicity.…”