Biocompatibility and radioprotection by newly characterized melanin pigment and its production from Dietzia schimae NM3 in optimized whey medium by response surface methodology

Abstract

Purpose To characterize and optimize the productivity of melanin using an extremotolerant actinobacterium, Dietzia schimae NM3, for the first time. Methods An extracellular brown pigment produced by D. schimae NM3 in the nutrient broth and cheese whey medium by adding L-tyrosine. The extracted melanin was analyzed by UV-visible, HPLC, and FTIR assays. The radical scavenging activity (by DPPH) and sun protection factor (SPF) of the extracted melanin were measured. The melanin cytotoxicity was assayed by MTT and chromate biosorption was measured by atomic absorption spectroscopy. Finally, melanin production by D. schimae NM3 was optimized by response surface methodology (RSM) using Box-Behnken design in the whey medium. Result The purified melanin showed similar peak to the standard melanin (SIGMA) at 3.5 min in HPLC, and C=O bands, NH2, CH, C-N, and aromatic groups by FTIR. The radical scavenging activity (by DPPH) and SPF of the extracted melanin were obtained 188.9% and 20.22, respectively. Using MTT assay, the melanin revealed non-toxic effect on the normal human fibroblast (HFB) cell culture. The melanin yield 790 mg l−1, and tyrosinase activity 3400 U ml−1 were obtained in the medium contained whey powder [5% (w v−1)], L-tyrosine 2.5 g l−1, CuSO4 0.013 g l−1, and pH 10.5, incubated at 32 °C for 3 days. The ANOVA results indicated significant P-value, model F-value, and probability, with insignificant lack of fit. After optimization with mono-factors, the nutrient broth came up with melanin yield as 1.2 g l−1 and tyrosinase activity as 4040 U ml−1. Conclusion This is the first report of melanin production by D. schimae NM3 and this natural melanin showed valuable biological properties such as high antioxidant activity and radioprotection (SPF) and the biocompatibility to human cell line.

Suggested Sustainable Medical and Environmental Uses of Melanin Pigment From Halotolerant Black Yeast Hortaea werneckii AS1

“…H. werneckii AS1 melanin was shown to be non-cytotoxic, with an IC 50 greater than 100 μg/ml. Similarly, but at a higher concentration, purified melanin from Dietzia schimae NM3 at a concentration of up to 250 μg/ml showed no toxicity toward normal human fibroblast cell culture (HFB) ( Eskandari and Etemadifar, 2021 ). Also, P. putida ESACB 191 melanin tested against A375, HeLa Kyoto, HepG2, and Caco2 cell lines, showed an elevated IC 50 values of 1.77, 2.51, 0.89, and 1.08 mg/ml, respectively ( Ferraz et al, 2021 ).…”

Simultaneous improvement of lincomycin A production and reduction of lincomycin B levels in Streptomyces lincolnensis using a combined medium optimization approach

“…The traditional "one-factor at a time" optimization strategy requires a considerable amount of time and labor, and often leads to unreliable results and inaccurate conclusions. As an alternative, statistical strategy is an efficient approach to accounting for a large number of variables and has been effectively applied to optimize cultivation processes (Mansouriieh et al 2019;Fridous et al 2020;Eskandari and Etemadifar 2021).…”

Phenotypic Switching of B16F10 Melanoma Cells as a Stress Adaptation Response to Fe3O4/Salicylic Acid Nanoparticle Therapy

“…Melanin is a vital molecule with many biological functions—as sunscreen and radioprotection [ 46 , 47 , 48 ], as an antioxidant [ 49 , 50 ], and as a scavenger of toxic materials [ 51 ]—and has immunomodulatory [ 52 , 53 ], hepatoprotective [ 54 ], anti-inflammatory [ 55 ], and anticarcinogenic properties [ 50 ]. Melanogenesis has been intensively studied, and the results, sometimes contradictory, have highlighted a wide range of pigmentation effects in modulating melanoma cell traits [ 56 ].…”