Microbiotechnology Based Surfactants and Their Applications

Biosurfactants are structurally diverse group of bioactive molecules produced by a variety of microorganisms. They are secondary metabolites that accumulate at interfaces, reduce surface tension and form micellar aggregates. This research topic describes few novel microbial strains with a focus on increasing our understanding of genetics, physiology, regulation of biosurfactant production and their commercial potentials. A major stumbling block in the commercialization of biosurfactants is their high cost of production. Many factors play a significant role in making the process cost-effective and the most important one being the use of low-cost substrates such as agricultural residues for the production of biosurfactants. With the stringent government regulations coming into effect in favor of production and usage of the bio-based surfactants, many new companies aim to commercialize technologies used for the production of biosurfactants and to bring down costs. This Research Topic covers a compilation of original research articles, reviews and research commentary submitted by researchers enthusiastically working in the field of biosurfactants and highlights recent advances in our knowledge of the biosurfactants and understanding of the biochemical and molecular mechanisms involved in their production, scale-up and industrial applications. Apart from their diverse applications in the field of bioremediation, enhanced oil recovery, cosmetic, food and medical industries, biosurfactants can also boast off their unique eco-friendly nature to attract consumers and give the chemical surfactants a tough competition in the global market. This biosurfactant focused research topic aims to summarize the current achievements and explore the direction of development for the future generation of biosurfactants and bioemulsifiers. Some of the biosurfactant optimization processes presented are well-structured and already have a well-established research community. We wish to stimulate on-going discussions at the level of the biosurfactant production including common challenges in the process development, novel organisms and new feedstock and technologies for maximum benefit, key features of next generation biosurfactants and bioemulsifiers. We have compiled the research outputs of international leaders in the filed of biosurfactant particularly on the development of a state-of-the-art and highly-efficient process platform

Anaerobic digestion enhancement with microbial electrolysis cells: Is biomethane production the direction to go for commercialization?

The engineering of replacements for crude oil is a priority within industrial biotechnology. Biogas, produced by anaerobic digestion (AD) during organic waste degradation, has been used for electricity generation and heating. Microbial electrolysis cells (MECs) are an emerging technology which when combined with AD can produce higher yields of such energy whilst simultaneously treating waste water and sludge. MECs are bioelectrochemical systems which utilize the metabolism of microbes to oxidize organics. The majority of the research has been focused on biohydrogen production, despite associated issues, which has resulted in poor commercialization prospects. Consequently, scientists are now suggesting that methane production should be the focus of MEC technology. This chapter presents lab research on the bioprocessing of biomethane using AD and MECs and addresses important issues, namely the lack of pilot-scale studies. Downstream processing techniques are discussed, as well as a novel suggestion of further utilising MECs in the purification process

Bioprocessing Requirements for Bioethanol:Sugarcane vs. Sugarcane Bagasse

This chapter discusses alternative energy sources and the advantages of biofuels over fossil fuels. It outlines the main steps of bioethanol production and suggests some alternative sources as potential feedstock. The core focus of this chapter is to examine new research which considers the use of agricultural waste as a feedstock for bioethanol production rather than conventional feedstocks such as sugarcane and corn. The advantages of sugarcane bagasse as a feedstock are discussed in detail and the bioprocessing requirements are studied in comparison to traditional methods that use sugarcane as the feedstock. The chapter concludes by briefly outlining further research that could potentially improve these processes. </jats:p

Biological reduction of iron to the elemental state from ochre deposits of Skelton Beck in Northeast England

Ochre, consequence of acid mine drainage, is iron oxides-rich soil pigments that can be found in the water drainage from historic base metal and coal mines. The anaerobic strains of Geobacter sulfurreducens and Shewanella denitrificans were used for the microbial reduction of iron from samples of ochre collected from Skelton Beck (Saltburn Orange River, NZ 66738 21588) in Northeast England. The aim of the research was to determine the ability of the two anaerobic bacteria to reduce the iron present in ochre and to determine the rate of the reduction process. The physico-chemical changes in the ochre sample after the microbial reduction process were observed by the production of zero-valent iron which was later confirmed by the detection of elemental Fe in XRD spectrum. The XRF results revealed that 69.16% and 84.82% of iron oxide can be reduced using G. sulfurreducens and S. denitrificans respectively after 8 days of incubation. These results could provide the basis for the development of a biohydrometallurgical process for the production of elemental iron from ochre sediments

Rhamnolipid biosurfactants – Past, Present and future scenario of global market

Biosurfactants are natural surface active agents produced by various microbes (bacteria, yeast and fungi) and plants. There are several categories of biosurfactants which are marking their presence felt in the international market viz. sophorolipids, lipopeptides, methyl ester sulphonate (MES), alkyl polyglucoside (APG), sorbitan esters and sucrose esters however rhamnolipids - the glycolipid biosurfactants - produced mostly by Pseudomonas species are believed to be the future biosurfactant market leaders due to their significant applications. Pseudomonas species produce rhamnolipids in the presence of immiscible substrates such as n-alkanes, hexadecane and several oils. The global biosurfactant market is expected to reach $2.8 billion in 2023, which includes both microbial and plant based surfactants. The rhamnolipid market is expected to grow at a compound annual growth rate of 5.4% from 2014 to 2020 owing to the widespread applications of rhamnolipids in various sectors. The present article gives analytical opinion on the current market growth rate of rhamnolipids, key players in rhamnolipid manufacturing, the obstacles faced by the industry and the factors that are holding back rhamnolipids to become market leaders