Isolation and characterization of tyrosinase inhibitor-producing microorganisms from marine environment

Abstract

Tyrosinase inhibitor‐producing microorganisms were isolated from the marine environment and characterized. Out of about 500 isolates from various sea areas, only three strains that were isolated from sediment samples of Off‐Izu Islands and Sagami Bay were found to produce the inhibitors. Among the three, strain H1‐7 that was isolated from Off‐Izu Islands had significantly and constantly the strongest inhibitory activity (1000–2500 U/mL) and was selected for further studies on the identification of the strain and production of the inhibitor. The strain showed abundant to moderate growth covered with aerial mycelium on most media except for Miura’s medium and cornmeal agar, forming a white sparse mycelial mat at first and later a conidial area shaded yellowish white to greenish yellowish gray. The diameter of the aerial mycelium without seawater was much larger than the medium with seawater on all the media tested. It had antimicrobial activity against most microbes tested. Based on the taxonomical characteristics, strain H1‐7 belonged to the genus Trichoderma and was named Trichoderma sp. H1‐7. The optimal medium for the production of the inhibitor was investigated by using shake flasks and an improved basal medium. The maximum production of the inhibitor was observed in a medium consisting of 2% soluble starch, 1% glucose, 0.5% Bacto‐peptone (Difco) and 0.5% Bacto‐yeast extract (Difco) at pH 7.5 in 50% (v/v) seawater for 2 days with shaking.

Phenotypic characterization and cultivation conditions of inhibitor-producing fungus isolated from marine sediment

“…strain H1-7 was used in the present study. 9 The strain was grown in a medium containing, 2.0 g/L glucose, 0.5 g/L Bacto-peptone (BD Difco, New York, NY, USA) and 15.0 g/L agar in distilled water, pH 8.0. Trichoderma atroviride ATCC 32173 was obtained from ATCC (Manassas, VA, USA).…”

“…H1-7, isolated from the Off-Izu Islands, had the strongest inhibitory activity of all the positive isolates. 9 After it was discovered, the strain's ability to prevent the black discoloration of perishable food was investigated. 10 However, its taxonomical characterization and TI production have not yet been elucidated.…”

“…Among them, Trichoderma sp. H1‐7, isolated from the Off‐Izu Islands, had the strongest inhibitory activity of all the positive isolates 9 . After it was discovered, the strain's ability to prevent the black discoloration of perishable food was investigated 10 .…”

Tyrosinase inhibitory activity of supernatant and semi-purified extracts from squid pen fermented with Burkholderia cepacia TKU025

“…H1-7 [14], Aspergillus oryzae BCRC 32288 [3], Myrothecium sp. MFA58 [15], fungus YL185 [16], and the bacterium of Streptomyces roseolilacinus NBRC 12815 [17].…”

Screening of Tyrosinase Inhibitor, Antioxidant and Cytotoxicity of Dried Sea Cucumber from Tomini Bay, Indonesia

“…This is related to the content of collagen, fucoidan, and phenolic compounds that found in sea cucumbers. 11,12 Aside from being a cosmetics ingredient, biodiscovery of anticancer compounds from sea cucumber is also carried out by many researchers. 1 Sea cucumbers have attractive anticancer properties because they contain high saponin compounds.…”