Data on the characterization of non-cytotoxic pyomelanin produced by marine Pseudomonas stutzeri BTCZ10 with cosmetological importance

The article focuses on data dealing with characterization of black brown melanin produced by marine bacteria Pseudomonas stutzeri BTCZ10. Figures deal with the production of melanin by strain BTCZ10 and characterization of the pigment using biophysical techniques. Table presents the data on photo-protective ability of melanin when blended with commercial sunscreens.


a b s t r a c t
The article focuses on data dealing with characterization of black brown melanin produced by marine bacteria Pseudomonas stutzeri BTCZ10. Figures deal with the production of melanin by strain BTCZ10 and characterization of the pigment using biophysical techniques. Table presents

Subject area
Biotechnology More specific subject area Pigment Biology, Bacterial Melanins Type of data Value of the data Data explores the biophysical characteristics of bacterial melanin which will help in understanding the structural and functional characteristics of the pigment.
The data presented deals with the Sun Protection Factor (SPF) enhancement by bacterial melanin when blended with commercial sun screens; SPF enhancement is of great cosmetological importance.
The cytotoxicity data of melanin gives insight into the utility of the pigment for more applications.

Data
The data describes the production of melanin by Pseudomonas stutzeri BTCZ10 ( Fig. 1) and its biophysical characterization (Fig. 2). Sun Protective factor enhancement by the bacterial pigment is tabulated (Table 1). Dataset on cytotoxicity is presented (Fig. 3).

Experimental materials
Kojic Acid and Sulcotrione were purchased from Sigma Aldrich, USA. All other chemicals used were analytical grade from Himedia chemicals, India. L929 mouse fibroblast cell lines utilized for cytotoxicity evaluation were maintained in Dulbecco's modified eagles media (Himedia, India) supplemented with 10% FBS (Fetal Bovine serum) (Invitrogen, USA) and grown to confluence at 37°C at 5% CO 2 in a CO 2 incubator (Eppendorf, Germany).The melanin producing Pseudomonas stutzeri BTCZ10 was isolated from 96 m depth grab samples collected during Sagar Sampada Cruise #305 from Arabian Sea (9°6′N, 75°22′ E).

Production, extraction and purification of melanin
The bacteria was inoculated in tyrosine basal broth [1] and incubated at 37°C for 180 h. Melanin production kinetics was studied by sampling at 12 h intervals and estimating bacterial growth (O.D 600 nm) and melanin production (O.D 400 nm) spectrophotometrically. The production medium was then centrifuged (5000 g for 10 min) to remove the cell debris. Resultant cell free supernatant was acidified (using 1N HCl) to pH below 2, allowed to stand for a week to precipitate melanin. Later, the melanin precipitate was boiled for one hour and washed thrice with 0.1N HCl, followed by water.  Thereafter, the precipitate was boiled with absolute ethanol for 10 min and kept at room temperature for a day; followed by two washes in ethanol and air dried to get purified melanin [2].
The 1 H NMR spectra were obtained at 27.4°C on Bruker Avance III, 400 MHz. The NMR conditions were as follows: spectral width, 8223 Hz; acquisition time, 3.98 s; recycle delay, 2 s; and number of scans, 64.
The thermal properties of the extracted, purified melanin were examined by TGA instrument (Perkin Elmer, Diamond, USA). The sample was scanned from 40-930 o C with a heating rate of 10 o C min −1 .
For melanin metabolism evaluation, inhibitors like Kojic acid (50-400 μM) and Sulcotrione  μM) and the combination of both were added to the melanin production medium [1]. And melanin production was monitored spectrophotometrically at 400 nm.

Sun Protection Factor of melanin
Sun Protection Factor (SPF) of melanin blended with commercial sunscreens was estimated by a modified protocol of Suryawanshi et al., 2015 [4]. Commercial sunscreens of 0.1 g were added to 10 mL of absolute ethanol. Melanin was added at a concentration of 0.005% to this mixture. Absorbance of the mixture in the UV range (290-320 nm) was quantified at 5 nm intervals using ethanol as the blank.

Transparency document. Supporting information
Supplementary data associated with this article can be found in the online version at https://doi. org/10.1016/j.dib.2018.04.123.