Low Cost Production Of Biosurfactant From Different Substrates And Their Comparative Study With Commercially Available Chemical Surfactant

Samadhan Waghmode, Chandrashekhar Kulkarni, Sneha Shukla, Priyanka Sursawant, Chaitanya Velha

Abstract:

Biosurfactants are amphiphilic compounds produced by various bacteria and fungi which reduce surface and interfacial tension. In this work, the biosurfactant produced by Bacillus subtilis strain  isolated from soil samples was characterized and its properties compared with commercially available chemical surfactants. Bacillus subtiliswas used for the production of biosurfactant and its activity was tested against crude vegetable oil. The crude biosurfactant was produced using four different  substrates and its emulsification activity was compared against sodium dodecyl sulphate (SDS). The results showed that the isolated bio surfactant from coconut waste showed the highest emulsification activity even more than sodium dodecyl sulphate (SDS) which is a commercial chemical surfactant. Furthermore its antimicrobial activity was checked against Staphylococcus aureus, Escherichia coli, Pseudomonas and Salmonella typhimurium. The study concludes that coconut and soyabean waste  are the most ideal substrate for biosurfactant biosynthesis, which may have potential industrial applications.

Keywords: Biosurfactant, Bacillus subtilis, Emulsification, Waste Management

1. INTRODUCTION
In recent years industries have generated a large amount of tropical agricultural residues. Their disposal causes several environmental problem therefore there has been an increasing trend towards more efficient utilization of agro industrial residues like oil cakes, wheat bran, soya bean waste, sesame waste, coconut waste, bagasses etc. These residual by-products serve as an ideal substrate for fermentation processes to produce different commercially important compounds.[1] Mostly agricultural products are utilized as source of raw material as they are produced in large quantities, contain large amount of usable proteins and carbohydrates with some amount of oil residues, no storage problem, easily available and cheap. Surfactants are molecules that concentrate at interfaces and decrease surface and interfacial tension [2]. These compounds find applications in an extremely wide variety of industrial processes involving emulsification, foaming,  detergency, wetting, dispersing or solubilization [3, 4]. However, naturally occurring surface-active compounds derived from microorganisms, also called biosurfactants, are attracting attention as they offer several advantages over chemical surfactants, such as low toxicity, inherent good biodegradability and ecological acceptability [5]. Biosurfactants are amphiphilic biological compounds produced extracellularly or as part of the cell membranes by a variety of yeast, bacteria and filamentous fungi [6, 7] from various substances including sugars, oils and wastes. The unique properties of biosurfactants allow their use and possible replacement of chemically synthesized surfactants in a number of  industrial operations [8]. Biosurfactants reduce surface tension, Critical Micelle Concentration (CMC) and interfacial tension in both aqueous solutions and hydrocarbon mixtures [9, 10] In the present study, we have optimized the production of biosurfactant from Bacillus subtilis and characterized it. Investigation was carried out on its emulsification capacity as bio preservative in food. Different parameters were tested to optimize for the growth of the strain.

Download Complete Research Paper