Ashish Sachan

Detection of major phenolic acids from dried mesocarpic husk of mature coconut by thin layer chromatography

Abstract This is a report of extraction and identification of phenolic acids present in the dried mesocarpic husks of mature coconut fruit. The total phenolic content of the husk material was 13.0 mg/g dry wt. 4-Hydroxybenzoic acid (4-HBA) and ferulic acid contents were identified and analysed in the husk fractions extracted by mild alkali hydrolysis (with 0.1 M NaOH). Detection of ether-linked phenolic acids (by treatment with 2 M NaOH) yielded 2.2 mg/g dry wt. of 4-HBA and 0.1 mg/g dry wt. of ferulic acid. Our results demonstrate that mesocarpic husk materials can form an alternative source of 4-HBA.

Biotransformation of p-coumaric acid by Paecilomyces variotii

Aims:  To investigate the biotransformation of p‐coumaric acid into p‐hydroxybenzoic acid (p‐HBA) by Paecilomyces variotii Bainier MTCC 6581.

An efficient isocratic separation of hydroxycinnamates and their corresponding benzoates from microbial and plant sources by HPLC

A rapid HPLC‐based separation method was developed to analyse phenolic flavour components. In the present study, ferulic acid, 4‐coumaric acid, 4‐hydroxybenzoic acid, 4‐hydroxybenzaldehyde, vanillic acid and vanillin were chromatographed on various C18 columns (Prodigy™ ODS2, Synergi™ Hydro‐RP, Lichrosorb® and Columbus™). A dual‐wavelength UV detector was used for the precise identification of the eluted components. An isocratic elution with aqueous trifluoroacetic acid (1 mM)/methanol (17:8) at a flow rate of 1.0 ml/min separated all the above six phenolic compounds within 21 min on a C18 reverse‐phase column (Synergi™ Hydro‐RP) with stable baseline resolution.

Production of natural value-added compounds: an insight into the eugenol biotransformation pathway

During the past few years, the production of natural value-added compounds from microbial sources has gained tremendous importance. Due to an increase in consumer demand for natural products, various food and pharmaceutical industries are continuously in search of novel metabolites obtained from microbial biotransformation. The exploitation of microbial biosynthetic pathways is both feasible and cost effective in the production of natural compounds. The environmentally compatible nature of these products is one major reason for their increasing demand. Novel approaches for natural product biogeneration will take advantage of the current studies on biotechnology, biochemical pathways and microbiology. The interest of the scientific community has shifted toward the use of microbial bioconversion for the production of valuable compounds from natural substrates. The present review focuses on eugenol biotransformation by microorganisms resulting in the formation of various value-added products such as ferulic acid, coniferyl alcohol, vanillin and vanillic acid.

Transformation of ferulic acid to 4-vinyl guaiacol as a major metabolite: a microbial approach

The majority of the flavours and fragrances used worldwide are produced by chemical synthesis at low price. However, consumers prefer natural compounds because of increasing health and nutrition awareness in routine life. Hence, biotransformation is an alternative process to produce natural aroma compounds. Microorganisms have been gradually used more to produce natural aroma compounds with various applications in food, agriculture and pharmaceutical industries. This paper reviews the role of microorganisms in the transformation of ferulic acid to 4-vinyl guaiacol. The microbial processes based on biocatalytic method are discussed in terms of their advantages over chemical synthesis, plant cell cultures and enzyme catalyzed reactions. Thus, the transformation of ferulic acid by microorganisms could have possible use in food, pharmaceutical industry and become an increasingly important platform for the production of natural aroma compounds.

Syntrophics Bridging the Gap of Methanogenesis in the Jharia Coal Bed Basin

The bituminous and sub-bituminous rank of coals is being produced from the Jharia basin of Jharkhand which is the largest producer of CBM in India. Although there have been many reports on methanogenesis from Jharia, the present study deals with the special emphasis on the syntrophic microbes which can act as catalyst for the hydrogenotrophic methanogenesis. Using the metagenomic approach followed by 454 pyro sequencing, the presence of syntrophic community has been deciphered for the first time from the formation water samples of Jharia coal bed basin. The taxonomic assignment of unassembled clean metagenomic sequences was performed using BLASTX against the GenBank database through MG-RAST server. The class clostridia revealed a sequence affiliation to family Syntrophomonadaceae and class Deltaproteobacteria to family Desulfobacteraceae, Pelobacteraceae, Syntrophaceae, and Syntrophobacteraceae. Results revealed the possibility of thermobiogenic methanogenesis in the coal bed due to the presence of syntrophs related to Syntrophothermus genus. The presence of such communities can aid in biotransformation of coal to methane leading to enhanced energy production

Biosurfactants: A Multifunctional Microbial Metabolite

During the 1960s, the science of biosurfactants was in its infancy and received attention mainly as hydrocarbon dissolving agents. Recently biosurfactants have emerged as the most versatile product of the modern microbial biotechnology. Owing to its biodegradable nature, it has been considered as “green chemical.” Recently, increasing awareness toward sustainable ecosystem and environmental protection has resulted in a concerted research in biosurfactant as a promising substitute of chemical surfactants. It can be produced from nonrenewable resources, with alternative synthesis from economical renewable feedstocks. Apart from the stability at relatively adverse environments, these compounds are readily biodegradable in the environment. Functional properties of these compounds are being conferred by their structural diversity which varies among the microbial community. These compounds may provide advantages in a particular ecological niche or may be responsible for the niche-specific behavior of the producer microorganism. Diverse properties encompassed by biosurfactants are wetting, dispersion, emulsification, foaming, cleansing, phase separation, reduction in viscosity, and surface activity. It serves a broad spectrum of industries like petroleum, paint, paper, textile, leather, agriculture, cosmetic, food processing, agriculture, and pharmaceutical industries, thereby plays a significant role in white biotechnology.

Microbial production of 4-vinylguaiacol from ferulic acid by Bacillus cereus SAS-3006

Abstract Ferulic acid is an abundant cinnamic acid derivative found in the plant kingdom. It is a commercially available substrate utilized to produce flavor compounds such as 4-vinylguaiacol (4-VG), vanillin, and vanillic acid. The isolate Bacillus cereus SAS-3006 was screened and selected based on its ability to produce 4-VG upon ferulic acid biotransformation. It was identified based on morphological and physiochemical characteristics and its 16S ribosomal DNA sequence (GenBank accession number: KF699134). A maximum amount (79.4 mg/L) of 4-VG accumulation was observed on the 5th day of incubation when the culture was grown on 2.5 mM ferulic acid as sole carbon source. Further conversion of 4-VG to other intermediates such as vanillin, vanillic acid, protocatechuic acid, acetovanillone, and vanillyl alcohol was not observed. In-vitro conversion of ferulic acid to 4-VG was also studied with cell extracts of B. cereus SAS-3006. The present study provides the first evidence for production of 4-VG as the sole product using B. cereus SAS-3006.

Ferulic Acid Decarboxylase from Bacillus cereus SAS-3006: Purification and Properties

The cell-free extract of Bacillus cereus SAS-3006 strain grown on the medium containing ferulic acid was used as a source of the enzyme ferulic acid decarboxylase. This key enzyme, playing a vital role in the conversion of ferulic acid, was purified to homogeneity by anion-exchange chromatography from Bacillus cereus SAS-3006. The optimal pH and temperature for enzyme activity were found to be 6.5 and 37 °C, respectively. Kinetic studies indicated the K m and V max values of the purified ferulic acid decarboxylase were 0.0118 mM and 0.333 U, respectively. The enzyme activity was not inhibited by any of the studied metal ions viz. Fe2+, Fe3+, Ca2+, Mg2+, Mn2+, and Zn2+ at 2.0 mM of concentration. The enzyme was found to be activated and expressed inside the cells adequately by the substrate ferulic acid.

Biosurfactant Production by Pseudomonas fluorescens NCIM 2100 Forming Stable Oil-in-Water Emulsions

Pseudomonas fluorescens NCIM 2100 was studied for its potential to produce extracellular biosurfactant in the nutrient broth medium supplemented with diesel (2%) as an additional carbon source. Biosurfactant production was checked based on oil spread and drop collapse test. Emulsification index test was conducted to determine the emulsifying ability of the crude biosurfactant produced. The emulsification index, minimum surface tension and production of crude bioemulsifier were found to be 90.38% with diesel, 34.40 ± 0.03 mN/m and 2.80 ± 0.45 g/L respectively. Maximum product accumulation occurred during stationary phase of the bacterial growth curve. Crude biosurfactant produced was stable, withstanding a wide temperature (37–80 °C) and pH range (7–10.5), with an E-24 Index value greater than 50%. Produced biosurfactant has an efficient emulsifying ability. Most of the emulsions formed with tested aliphatic hydrocarbons and ester-based vegetable oils were stable. Emulsions formed with different hydrophobic substrates were oil-in-water (o/w) in nature.