Production, purification, and process optimization of intracellular pigment from novel psychrotolerant Paenibacillus sp. BPW19

Abstract

A pink pigment-producing bacterial strain was isolated from wastewater and identified as Paenibacillus sp. BPW19. The motile bacterial strain was Gram-positive, acid fermenting, glucose, sucrose utilizing and rod-shaped with an average cell length of 1.55 μm as studied under the Environmental Scanning Electron Microscope. Even though being psychrotolerant, the cell growth condition of BPW19 was optimized as 25 ºC along with pH 8, and 2.25% inoculum concentration considering the operational ease of the production. Sonication assisted solvent extraction produced 5.41% crude pigment which showed zones of exclusion against gram-negative strains Escherichia coli DH5α, Enterobacter sp. EtK3, and Klebsiella sp. SHC1. Gas Chromatography-Mass Spectrometry analysis of the crude pigment exhibited the dominant presence of major compounds as dotriacontane; 3,7 dimethyl 7 octanal; 1-eicosene and erucic acid. While column chromatography (ethanol:chloroform in 1:4 (v/v) ratio) purified pigment was identified as erucic acid using Nuclear Magnetic Resonance with a net yield of 3.06%.

Keywords

• Bacterial pigment
• Intracellular
• Microstructure
• Solvent extraction
• Chromatography