Exploration and Characterization of Melanin Pigment Produced by Actinomycetes

2022 ◽  
pp. 671-681
Author(s):  
Puja Gupta ◽  
Madangchanok Imchen ◽  
Ranjith Kumavath
Keyword(s):  
Melanin Pigment

scholarly journals Characterization of brown-black pigment isolated from soil bacteria, Beijerinckia fluminensis

2021 ◽  
Author(s):  
Mahesh H Joshi ◽  
Ashwini A Patil ◽  
Ravindra V Adivarekar
Keyword(s):  
Soil Bacteria ◽  
Iron Ore ◽  
Uv Light ◽  
Melanin Pigment ◽  
Black Pigment ◽  
Vis Spectroscopy ◽  
Alkaline Conditions ◽  
Amorphous Compounds ◽  
Maximal Production

Melanin is a ubiquitous pigment found in most organisms it is a dark-brown or black pigment formed by the oxidation of phenolic compounds. They are negatively charged amorphous compounds having quinone groups. In this study; melanin-producing microorganism was isolated from soil obtained from iron ore mine. The soil was enriched in modified Ashbys glucose broth for 15 days at 30°C further to which it was isolated on modified Ashbys agar at 30°C for seven days; the colonies showing pigmentation were selected for further study. Conditions were optimized for maximal production of melanin pigment. The effect of carbon nitrogen tyrosine and metal salts on pigment production was studied. Alkaline conditions were used to extract the pigment from cells, further characterized by UV-VIS spectroscopy for λ-max. FTIR was done to identify the native functional groups and XRD was performed to determine the melanins structure. TGA analysis was done to check its thermal stability. SEM was carried out to check the size and shape of the melanin pigment. The melanin pigment was also analyzed for UV protectant property which was studied by exposure of both melanized and non-melanized cells to UV light at 254nm. Key words: Beijerinckia fluminensis iron ore soil melanin and UV-protection.

Isolation and characterization of melanin pigment from yesso scallop Patinopecten yessoensis

2017 ◽  
Vol 16 (2) ◽  
pp. 279-284 ◽  
Author(s):  
Xiujun Sun ◽  
Biao Wu ◽  
Liqing Zhou ◽  
Zhihong Liu ◽  
Yinghui Dong ◽  
...  
Keyword(s):  
Melanin Pigment ◽  
Patinopecten Yessoensis ◽  
Yesso Scallop ◽  
Isolation And Characterization

Characterization of the melanin pigment of a cosmopolitan fungal endophyte

2004 ◽  
Vol 108 (8) ◽  
pp. 974-978 ◽  
Author(s):  
Trichur S. Suryanarayanan ◽  
Jagadesa P. Ravishankar ◽  
Govindan Venkatesan ◽  
Thokur S. Murali
Keyword(s):  
Fungal Endophyte ◽  
Melanin Pigment

Characterization of melanin pigment produced by Aspergillus nidulans

2011 ◽  
Vol 28 (4) ◽  
pp. 1467-1474 ◽  
Author(s):  
R. C. R. Gonçalves ◽  
H. C. F. Lisboa ◽  
S. R. Pombeiro-Sponchiado
Keyword(s):  
Aspergillus Nidulans ◽  
Melanin Pigment

Morphological Characterization of Mycobacteriophage R1

1974 ◽  
Vol 32 ◽  
pp. 254-255
Author(s):  
B. L. Soloff ◽  
T. A. Rado
Keyword(s):  
Carbon Source ◽  
Stationary Phase ◽  
Growth Phase ◽  
Minimal Medium ◽  
Morphological Characterization ◽  
Logarithmic Growth Phase ◽  
Complete Lysis ◽  
Lysogenic Culture ◽  
Logarithmic Growth

Mycobacteriophage R1 was originally isolated from a lysogenic culture of M. butyricum. The virus was propagated on a leucine-requiring derivative of M. smegmatis, 607 leu−, isolated by nitrosoguanidine mutagenesis of typestrain ATCC 607. Growth was accomplished in a minimal medium containing glycerol and glucose as carbon source and enriched by the addition of 80 μg/ ml L-leucine. Bacteria in early logarithmic growth phase were infected with virus at a multiplicity of 5, and incubated with aeration for 8 hours. The partially lysed suspension was diluted 1:10 in growth medium and incubated for a further 8 hours. This permitted stationary phase cells to re-enter logarithmic growth and resulted in complete lysis of the culture.

AEM analysis of crystallization in Ti-based amorphous alloys

1983 ◽  
Vol 41 ◽  
pp. 270-271
Author(s):  
A.R. Pelton ◽  
A.F. Marshall ◽  
Y.S. Lee
Keyword(s):  
Magnetic Properties ◽  
Amorphous Alloys ◽  
Amorphous Materials ◽  
Isothermal Annealing ◽  
Amorphous Matrix ◽  
Nucleation And Growth ◽  
Current Interest ◽  
Amorphous Films ◽  
Electrical And Magnetic Properties

Amorphous materials are of current interest due to their desirable mechanical, electrical and magnetic properties. Furthermore, crystallizing amorphous alloys provides an avenue for discerning sequential and competitive phases thus allowing access to otherwise inaccessible crystalline structures. Previous studies have shown the benefits of using AEM to determine crystal structures and compositions of partially crystallized alloys. The present paper will discuss the AEM characterization of crystallized Cu-Ti and Ni-Ti amorphous films.Cu60Ti40: The amorphous alloy Cu60Ti40, when continuously heated, forms a simple intermediate, macrocrystalline phase which then transforms to the ordered, equilibrium Cu3Ti2 phase. However, contrary to what one would expect from kinetic considerations, isothermal annealing below the isochronal crystallization temperature results in direct nucleation and growth of Cu3Ti2 from the amorphous matrix.

Characterization of Coherent, Ordered Precipitates in Nickel-Base Alloys

1973 ◽  
Vol 31 ◽  
pp. 144-145
Author(s):  
B. H. Kear ◽  
J. M. Oblak
Keyword(s):  
Stable Phase ◽  
Nickel Base Superalloy ◽  
Alloy 718 ◽  
Commercial Alloy ◽  
Precipitate Morphology ◽  
Continuous Precipitation ◽  
Nickel Base ◽  
Base Superalloy ◽  
Strengthening Precipitate

A nickel-base superalloy is essentially a Ni/Cr solid solution hardened by additions of Al (Ti, Nb, etc.) to precipitate a coherent, ordered phase. In most commercial alloy systems, e.g. B-1900, IN-100 and Mar-M200, the stable precipitate is Ni3 (Al,Ti) γ′, with an LI2structure. In A lloy 901 the normal precipitate is metastable Nis Ti3 γ′ ; the stable phase is a hexagonal Do2 4 structure. In Alloy 718 the strengthening precipitate is metastable γ″, which has a body-centered tetragonal D022 structure.Precipitate MorphologyIn most systems the ordered γ′ phase forms by a continuous precipitation re-action, which gives rise to a uniform intragranular dispersion of precipitate particles. For zero γ/γ′ misfit, the γ′ precipitates assume a spheroidal.

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