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A waste-based circular economy approach is proposed for the phycoremediation of an X-ray developer (XD) solution. The present study emphasizes the utilization of food waste (FW) and agri-compost media (ACM) as growth media for D. armatus for the subsequent bioremediation potential of XD solution-coupled lipid production. A 3:1 dilution (FW/ACM: XD.) was found to be suitable for the phycoremediation study of XD solution towards the % removal of biological oxygen demand (BOD), chemical oxygen demand (COD) and silver. The phycoremediation studies of diluted XD solution in FW demonstrated a 74.50% BOD removal, 81.69% COD removal, and 54.70% removal of silver. The growth of D. armatus in diluted XD solution in food waste was 1.37% lipid content. The phycoremediation of diluted XD solution with ACM resulted in 83.05% BOD removal, 88.88% COD removal and 56.30% silver removal with the concomitant lipid production of 1.42%. The optimal bioremediation coupled lipid production of D. armatus was observed on the 19th day of D. armatus cultivation in the developer effluent, along with food waste and agri-compost media, for 31 days. The study suggests a sustainable utilization of waste (FW and ACM) as a nutritive medium to scrutinize the phycoremediation of XD solution with a concomitant lipid production that can open up new avenues in phycoremediation coupled energy commodities production.

The present study involves the characterization and microalgal toxicity screening of diagnostic X-ray fixer solution toward utilization as a probable full-scale bioremediation study. The characterization results showed a BOD value of the waste X-ray fixer solution 11,833 ± 485.62 mg/l and 506,733 ± 251.66 ppm COD. The Scendesmus abundans was well grown using BBM, 1500 lx light intensity, 12 h:12 h light and dark conditions with 100 rpm shaking at 25 ± 1 °C on 1-month cultivation. The executed toxicity screening results of the diagnostic fixer solution on S. abundans with different dilutions have shown a promisable growth between 15 and 21 days with the 3 BBM:1 X-ray fixer solution dilution with a maximum cell count of 370 × 104 cells/ml on the 21st day of microalgal cultivation. The present study puts forth the physical and chemical parameters of X-ray fixer solution with proven toxicity tolerance limits of S. abundans toward the probable logical step of algal-based bioremediation of fixer solution.

Background: Bioactive peptides from κ-casein have immense therapeutic potential as prophylactic formulations. Among these, casoplatelin is a κ-casein derived bioactive peptide with anti-thrombotic activities. Aim: Herein, we report the production of casoplatelin in an E. coli expression system (using a pBAD vector) and show in silico modeling of its interactions. Methods: A synthetic DNA construct encoding casoplatelin was designed with pepsin cleavage sites before and after the synthetic construct to allow the release of the peptide from the pro-peptide. Results: A novel recombinant approach was demonstrated for the production of casoplatelin, and anti-platelet aggregation activities of the product were confirmed. Also, casoplatelin structures were characterized in silico and then implemented to determine potential structural interactions with fibrinogen. Conclusion: The present study showcases the recombinant approach for biopeptide production and its interaction with fibrinogen through in silico approach.

Sustainable transformation of biomass into a wide range of valuable chemicals, fuels, and materials is the eventual goal of a biorefinery. Algal feedstock (microalgae and macroalgae) is a principal component of third-generation (3G) biorefinery empowering the bio-renewables industry. While first-generation (1G) biorefineries are commercially viable, products (fuels and commodity chemicals) from second-generation (2G) and 3G biorefinery are not yet commercially competitive due to the gross technical challenges, scalable and production cost issues. Because of the inherently diversified nature of feedstock used in 3G biorefineries, a myriad of specific bioproducts can be produced. Furthermore, stable food/feed supply, environmental concerns, climate change, and geopolitical issues have necessitated the exploration of 3G feedstocks into fuels and renewable chemicals. Considerable success has been seen in research laboratories in the last two or three decades which led to mature technical developments in algal biomass conversion. However, the scale-up issues are still posing a big challenge for the commercial exploitation of algal feedstock into fuels and chemicals. Nevertheless, various products such as nutraceuticals, pharmaceuticals, and cosmetics are successfully being produced from algal feedstock. This review paper describes the technical developments, industrial scenario, environmental issues, and range of diversified products from 3G biorefineries. Specially, we focus on the exploration of algal biomass into fuels and biochemicals via multidisciplinary technological routes.

The growing, existing demand for low-cost and high-quality hyaluronic acid (HA) needs an outlook of different possible production strategies from renewable resources with the reduced possibility of cross-infections. Recently, the possibility of producing HA from harmless microorganisms appeared, which offers the opportunity to make HA more economical, without raw material limitations, and environmentally friendly. HA production is mainly reported with Lancefield Streptococci A and C, particularly from S. equi and S. zooepidemicus. Various modes of fermentation such as batch, repeated batch, fed-batch, and continuous culture have been investigated to optimize HA production, particularly from S. zooepidemicus, obtaining a HA yield of 2.5 g L-1 - 7.0 g L-1. Among the different utilized DSP approaches of HA production, recovery with cold ethanol (4 degrees C) and cetylpyridinium chloride is the ideal strategy for lab-scale HA production. On the industrial scale, besides using isopropanol, filtration (0.22 um), ultrafiltration (100 kDa), and activated carbon absorption are employed to obtain HA of low molecular weight and additional ultrafiltration to purify HA of higher MW. Even though mature technologies have already been developed for the industrial production of HA, the projections of increased sales volume and the expansion of application possibilities require new processes to obtain HA with higher productivity, purity, and specific molecular weights. In this review, we have put forth the progress of HA technological research by discussing the microbial biosynthetic aspects, fermentation and downstream strategies, industrial-scale scenarios of HA, and the prospects of HA production to meet the current and ongoing market demands.

The present study explores the potential of Brassica juncea as a low-cost substrate for biodiesel production through the growth of oleaginous yeast. Firstly, the selected lignocellulosic biomass, i.e., Brassica juncea, was thermochemically pretreated using dilute sodium hydroxide. Optimization of thermochemical pretreatment resulted in significant removal of lignin and hemicellulose with 8.4% increase in cellulose content. Further, the sugar hydrolysate of pretreated biomass was used as a substrate for the growth of selected oleaginous yeast (Cryptococcus sp. MTCC 5455). Lipid and biomass production was optimized using central composite design (CCD) based on response surface methodology (RSM). Maximum biomass and lipid content of 32.50 g/L and 11.05 g/L, respectively, was obtained at 30 °C temperature, pH 6.0, and after 5 days of incubation. The oleaginous yeast lipid was further transesterified using immobilized lipase. The highest fatty acid methyl ester 15% FAME yield was obtained after 10 h of enzymatic reaction. Next, the results of specific gravity, viscosity, flash points, and cloud point of obtained biodiesels were conformed to the ASTM D975 standard. Overall, the present study put forth the cost-effective approach for lignocellulosic biomass-based oleaginous lipid production toward the green synthesis of biodiesel.

Study background: Traditional fermented foods are the source of probiotic bacteria which can be envisaged as formulation ingredients in various food and beverages. Scope and approach: The present research aimed to explore one of the Indian traditional recipes, “Tarvaani,” for nutritional and probiotic potential as a part of its healthy perspectives. Main findings and conclusion: The traditional recipe was found to contain the lactic acid bacteria and isolated. The isolated product showed prominent curdling activity after 48 h, and bacterial growth was seen in all the pH (pH 3–7) tested. The antibiotic susceptibility test found that streptomycin, vancomycin, and kanamycin were resistant to the bacterial culture, and imipenem, gentamycin, rifampicin, and tetracycline were found to be resistant susceptible to the bacterial culture according to zone diameter interpretative criteria given in ICMR SOP 2015. A clear halo zone around the tested colony was obtained in the amylase test, which indicated that starch was degraded and α-amylase was produced. The culture also showed prominent antimicrobial action and inhibited the growth of the pathogenic strains tested by a well-diffusion assay. Moreover, the isolates only showed no haemolysis activity after incubation at 30 ◦C for 24 h under anaerobic conditions. Overall, the present research findings showcase the nutritional and probiotic potential of Lactobacillus sp. of “Tarvaani” as a viable option as a formulation ingredient in traditional-based functional foods Universidade de Vigo/CISUG

Oleaginous yeast lipids have myriad of industrial applications that are gaining significant interest owing to shorter incubation, ability to use broad spectrum substrates, and quality lipids. However, the lipid content produced is low and need to enhance by optimization of varied parameters. In the present study, crude glycerol a by-product of biodiesel industry was supplemented to Trichosporon shinodae for lipid accumulation using central composite design (CCD) of response surface methodology (RSM). The developed quadratic model was found to be significant with the R2 value of 95.20% and adj. R2 value of 91.97%. An optimal lipid content of 49.85 ± 0.8% (w/w) was obtained using T. shinodae with 6.2% (v/v) inoculum volume, pH 3.6, C/N ratio 105, 1.52 (g/L) of MgSO4, and 4.55 mM FeSO4 in 120.72 h at 30 °C. Lipid composition from T. shinodae depicted the presence of linoleic acid (C18:2), oleic acid (C18:1), stearic acid (C18:0), palmitic acid (C18:0), myristic acid (C14:0), and lauric acids (C12:0), respectively. T. shinodae lipids have 61.1% (w/w) saturated fatty acids and unsaturated fatty acids proportion accord to 38.9% (w/w). Lipid composition of T. shinodae indicates that these lipids were suitable for synthesis of high value products like fuel additives, surfactants, detergents, and cleaning applications.

Microbial electrochemical processes are primary platforms for generating electricity or value-added products by relying on the interaction between electroactive microorganisms and electrodes by utilizing electron carriers like hydrogen and enzyme through the oxidation–reduction reactions. Microbial electrosynthesis (MES), initially introduced as electricity-driven bioproduction from CO2, offered a novel pathway to produce biochemicals that eventually contribute to the CO2 sequestration. While most of the previous reviews concentrate on these microbial electrochemical platforms jointly referred to as MXC, such as Microbial fuel cell and microbial electrolysis cell, MES has grown tremendously in recent years, requiring a severe update on the scientific information on this topic. In this mini-review, the significant achievements in MES, specifically towards the production of a wide array of specialty chemicals, have been addressed by summarizing the recent scientific breakthroughs of the MES technology. Furthermore, improving MES's performance through modification of electrodes and membranes and outlook section with the technical challenges and probable solutions have been discussed. The review summarizes the technological drawbacks of the MES's towards a sustainable commercial platform for industrial commodities production and proposes ways to overcome the existing technical challenges in a nutshell towards turning MES in a full-fledged industrial-scale production platform.

Metals represent a large proportion of industrial effluents, which due to their high hazardous nature and toxicity are responsible to create environmental pollution that can pose significant threat to the global flora and fauna. Strict ecological rules compromise sustainable recovery of metals from industrial effluents by replacing unsustainable and energy-consuming physical and chemical techniques. Innovative technologies based on the bioelectrochemical systems (BES) are a rapidly developing research field with proven encouraging outcomes for many industrial commodities, considering the worthy options for recovering metals from industrial effluents. BES technology platform has redox capabilities with small energy-intensive processes. The positive stigma of BES in metals recovery is addressed in this review by demonstrating the significance of BES over the current physical and chemical techniques. The mechanisms of action of BES towards metal recovery have been postulated with the schematic representation. Operational limitations in BES-based metal recovery such as biocathode and metal toxicity are deeply discussed based on the available literature results. Eventually, a progressive inspection towards a BES-based metal recovery platform with possibilities of integration with other modern technologies is foreseen to meet the real-time challenges of viable industrial commercialization.

The enhanced lipid accumulation in microalgae is envisioned under special stress conditions with the cost of algal growth, which in turn affects the overall lipid productivity. The selection of suitable stress conditions facilitates better lipid productivity without any harmful effect on microalgae growth and algal biomass production. In the present study, we have attempted to select the best salinity conditions towards better growth, biomass accumulation, and lipid productivity of microalgae. The study also envisaged testing the feasibility of the stepwise salinity stress-induced cultivation approach to minimize the growth penalty effect of microalgae. The highest specific growth rate (0.129, 0.133, 0.113 µday−1) and doubling per day (0.185, 0.193, 0.163 per day) were obtained at salinity concentration of 40 mM NaCl in BG-11 medium for Scenedesmus quadricauda (Sq19), Scenedesmus dimorphus (Sd12), and Chlorella sp. (Chl16), respectively. Maximal lipid content of 18.28, 30.70, and 32.19%, and lipid productivity of 8.59, 13.81, and 10.27 mg l−1 day−1 were achieved at 160 mM of NaCl in BG-11 media with the Sq19, Sd12, and Chl16 algal isolates, respectively. The utilization of stepwise salinity stress (160 mM) induced cultivation of Sd12 algal isolate results in higher lipid content (39.42%) and slightly improved lipid productivity than the control (without any stress, 20.4% lipid content). The results indicate the feasibility of enhancing the lipid content and productivity through the salinity-induced stepwise cultivation strategy.

Biofuels/Bioenergy is renewable in nature by mitigating the greenhouse gas emissions despite rapid economic growth and energy demand. Biodiesel and bioethanol production from renewable sources are gaining much attention but unable to translate the technologies into commercially ventures. Several technical challenges like the screening of algae/yeast for higher lipid accumulation/ethanol production, separation and purification of microalgae from contaminants, harvesting of microalgae, improving transesterification efficiency with meager solvent consumption, energy and time have been addressed using microfluidic devices. Besides, it has shown promising results in microbial fuel cell domain. Microfluidics and microreactors offer miniaturization of experiments by a very little expense of solvents, energy and time with higher precision results. Moreover, it provides 19.2% higher surface to volume ratio when compared with Petri dish (35 mm diameter) and microchannel (50 µm tall, 50 µm wide, and 30 mm long). Higher surface to volume ratio is helpful in the integration of the whole laboratory (i.e., lab-on-a-chip), where efficient screening of ethanol/lipid producer, higher transesterification efficiency could be ascertained. Due to the overwhelming potential of microfluidics in biofuel and bioenergy sectors, the present review article illustrated several examples to depict the importance of microfluidics towards high-throughput analysis of screening the potent microbial/microalgal strain, fabrication of microfluidic bioreactor, quality analysis of biofuel and bioenergy products.

Potato peel waste is one of the zero-value wastes with the potential of bioethanol production through the Waste to Energy (WtE) approach. The newly isolated, phenotypically characterized, and molecular identified high-altitude strain, B. amyloliquefaciens, shown promising starch hydrolysis (12.06 g/L reducing sugars) over acid hydrolysis and is capable of working at 30-50 °C and pH 6.0-8.0. The ethanol production by Acinetobacter sp. (a newly isolated, phenotypically characterized, molecular identified) has been modelled and optimized through the central composite design of response surface methodology by taking the fermentation variables as input variables and ethanol yield as the output variable. The ethanol production by Acinetobacter sp. showcased a non-linear relationship of fermentation variables with the ethanol yield (5.83 g/L) with a 99.11% desirability function (R

Ecofriendly dye decolorization is a prerequisite for textile industries to tackle hazardous textile effluents. In the present study, we have reported a laccase producing (19.12 ± 3.45 U/mL...

The future demands of transportation and industrial sectors necessitate groundbreaking research toward a sustainable energy source. Biogas from anaerobic digestion has been a well-studied research concept for the last two to three decades. The biogas technology suffers from the composition of unwanted contaminants (mainly CO2, H2S) in the production stream and utilization of cumbersome, energy-intensive removal technologies. The photosynthetic microalgae utilize the sequestered CO2 from biogas to synthesize different value-added products and aid biogas upgradation to attain the energy-rich biomethane. This chapter puts forth the positive attributes of photosynthetic microalgae-based biogas upgradation toward enhanced CO2 removal from biogas while meeting the natural grid system’s standards. Greater emphasis has been given toward photosynthetic biogas upgradation process set up, with possible integration with wastewater treatment and biomass production, the existing photobioreactors, influential process variables for better biogas upgradation, and discussion of the prospects of the photosynthetic biogas upgradation technology.

In the present scenario, the world’s energy demand is increasing every year in all the countries of world. Until now the major energy source is conventional fossil nonrenewable fuels, which are used for the daily applications of various types of energy. The needs of the bioeconomy are essential, and it will also reduce the dependence on nonrenewable energy source and also produce less pollution. In the last two decades, biohydrogen research has emerged as a promising alternative renewable energy source since it has a higher calorific value and did not produce CO2 during combustion process. However the biological production of biohythane (mixture of CH4 and H2) is more economically feasible to compare with CH4 or H2, and this also can be produced at the commercial level. In this chapter, the recent developments in the biomethane generation is discussed in detail along with their production from various substrates.

Oils and fats derived from oilseeds are important constituents of a healthy diet, which not only supplies calories but also help in absorbance of fat soluble vitamins such as A, D, E and K. Besides, oils/fats have multiple uses in medicine, cosmetics, fertilizers, biodiesel, paints and animal feeds. Similarly, oils/fats accumulated by oleaginous microbes (OM) are also gaining significant interest owing to the quality of lipids, which can be used either for food consumption or fuel purpose. To harness the potential of oils/fats from oilseeds and OM, development of efficient oil extraction techniques is quintessential. Oil extraction from oilseeds has been carried out widely using solvent extraction, where hexane is used; whereas in oleaginous microbes, widely used solvents are chloroform:methanol. However, usage of these solvents leads to toxicity and causes air pollution. Green solvents and extraction techniques have shown promising results in overcoming these advantages. These solvents and techniques are eco-friendly, green in nature, low in energy and solvent consumptions and higher efficiency in product formations. Moreover, through these solvents and techniques, the by-products in various applications of oilseeds like oilseed cake, which is rich in protein can be used effectively and ultimately reduce the overall cost of the process. In this chapter, green solvents such as bio-derived solvents, ionic liquids, deep eutectic solvents, their solubility parameters and optimization of solvent system for oil/lipid extraction have been discussed. In addition, green extraction techniques like enzyme assisted extraction (AEE), microwave assisted extraction (MAE) and ultrasound assisted extraction (UAE) have been lucidly elaborated.

An anodic syntrophic consortium (exoelectrogenic plus fermentative bacteria) able to use methanol as sole carbon source was developed for the first time in a bioelectrochemical system. In this frame, promising results were obtained in single chamber MFC, comparable to those obtained with readily biodegradable substrates. Regarding MEC operation, the presence of homoacetogenic bacteria led to electron recycling, avoiding net hydrogen production in single chamber MEC. In a double chamber MEC, satisfying results (in terms of coulombic efficiency and cathodic gas recovery) were obtained even though energy recovery still restrained the feasibility of the process. The approach used in this work with methanol opens a new range of possibilities for other complex substrates as electron donors for bioelectrosynthesis.

Lignocellulose biorefinery encompasses process engineering and biotechnology tools for the processing of lignocellulosic biomass for the manufacturing of bio-based products (such as biofuels, bio-chemicals, biomaterials). While, lignocellulose biorefinery offers clear value proposition, success at industrial level has not been vibrant for the commercial production of renewable chemicals and fuels. This is because of high capital and operating expenditures, irregularities in biomass supply chain, technical process immaturity, and scale up challenges. As a result, commercial production of biochemicals and biofuels with right economics is still lagging behind. To hit the market place, efforts are underway by bulk and specialty chemicals producing companies like DSM (Succinic acid, Cellulosic ethanol), Dow-DuPont (1,3-Propanediol, 1,4-Butanediol), Clariant-Global bioenergies-INEOS (bio-isobutene), Braskem (Ethylene, polypropylene), Raizen, Gran-bio and POET-DSM (Cellulosic ethanol), Amyris (Farnesene), and several other potential players. This paper entails the concept of lignocellulose biorefinery, technical challenges for industrialization of renewable fuels and bulk chemicals and future directions.

Cross-linked enzyme crystal (CLEC) and sol-gel entrapped pseudomonas sp. lipase were investigated for the esterification of lauric acid with ethanol by considering the effects of reaction conditions on reaction rate. The activation energy for the reaction was estimated to be 1097.58 J/mol and 181.75 J/mol for sol-gel and CLEC entrapped lipase respectively. CLEC lipase exhibited a marginal internal diffusion effect on reaction rate over sol-gel lipases and found to be interesting. The overall reaction mechanism was found to conform to the Ping Pong Bi Bi mechanism. The higher efficiency of sol-gel lipases over CLEC lipases in esterification reaction is mainly due to the combined effects of crowding, confinement and diffusional limitations.

Waste to the product approach was proposed for tuning environ-threat soybean husk towards lipolytic enzyme by integrating the invasive weed optimization with biomass and product dynamics study. The invasive weed optimization constitutes based on the non-linear regression model results in a 47 % enhancement in lipolytic enzyme using the optimization parameters of 7% Sigma Final, 9% exponent; Smax of 5 with a population size of 35 and Max. generations of 99. The biomass dynamic study showcases the dynamic parameters of 0.0239 µmax, 8.17 XLimst and 0.852 RFin values. The product dynamic studies reveal the kinetic parameters of kst, kdiv, PFin, which seem to be equal to −0.0338, 0.0896 and 68.1, respectively. Overall, the present study put forth the zero-waste (soybean husk) to the product (lipolytic enzyme) approach by introducing the novel “Invasive Weed Optimization” coupled with “Biomass and product dynamics” to the bioprocessing field.

Rationale: Table compression process has a profound effect on different quality attributes of table manufacturing process such as appearance, content uniformity, hardness, thickness, friability, Disintegration time and Dissolution time. Among all the table compression parameters, feeder speed, precompression, main compression forces and Turret speed have a substantial effect on tablet properties. Aim: Statistical modeling and optimization approach has been utilized to model and optimize Levocetirizine tablet formulation compression process using Response Surface Methodology. Methods: A 3-level Central Composite Design has been chosen by taking turret speed, pre & main compression forces and Feeder speed as input variables and tablet characteristics (hardness, thickness and disintegration time) as output variables. Results: Non-linear regression models have obtained with respective to output variables (hardness, thickness and disintegration time) with R 2 values of 99.26%, 98.01% and 99.84% for hardness, thickness and disintegration time, respectively. The effect of individual, square and interaction terms on the table hardness, thickness and disintegration has been summarized through the significance test and depicted through response surface plots. An optimized tablet characteristic of 15.3 kP hardness, 3.7 mm thickness and 226 sec disintegration time have been obtained using predicted tablet compression process variables of 68 rpm Turret speed, pre and main compression forces of 2.05 and 7.95 kN respectively and Feeder speed of 27 rpm. Conclusion: The results demonstrated the reliability of the proposed statistical approach to model and optimized the compression studies of levocetirizine tablet formulation. The present study helps in scale-up studies of tablet compression during Levocetirizine tablet formulation. Key words: Central Composite Design, Levocetirizine, Optimization, Statistical Modeling, Tablet Compression.

Microalgae are one of the renewable sources for pharmaceutical compounds as well as biofuels. The microalgae sector is growing rapidly due to the scarcity of substrate sources, more yields, and the GRAS (generally recognized as safe) status of compounds associated with microalgae. Due to this GRAS status, the algal products are beneficial not only for the pharmaceutical but also for the food industry. In this review, insights into the different process aspects and obstacles of pharmaceutical and nutraceutical compounds derived from microalgae on large-scale are discussed. Various culture production methods like photoautotrophic, heterotrophic, and mixotrophic processes have been included and recent advances in metabolic strategies for upgrading the microalgal technology for pharmaceutical and nutraceutical compounds are highlighted as well as the prospects in the field presented. Overall, this review discusses the question, how microalgae can be a great advantage for the pharmaceutical and nutraceutical industry.

Bioelectrochemical systems (BESs) are systems driven by biocatalytic reactions with the aid of electrogenic microbes. The self-replication and mass-free supply of redox equivalents of BESs possess added advantage for bioelectricity generation and effluent treatments. Microalgae coupled BESs facilitate bioelectricity and industrial commodities production along with the removal of toxic compounds of industrial effluents. This article presents the possible potential applications of combined algae-BES for removal of unwanted nutrients and power generation along with recent studies with these systems. Finally, the chapter puts forth the substantial and technologic advancements of microalgae in BES along with the challenges and prospects of the field.

Industrialization, infrastructure development, energy production, and their use are the engines of the economic growth of any country. These growth drivers permanently require the uninterrupted supply of energy and fuels. Currently, gasoline and its products are a primary source which is fulfilling the energy requirement. However, their excessive usage as an energy source is generating the greenhouse gasses (GHGs), which deteriorate the environment and eventually cause negative impact on the climate. Currently, more than 85% of the world’s total energy needs are being fulfilled by crude petroleum resources. Therefore, it is necessary to look out for alternative fuels that are renewable and cause a low impact on the environment. Because of environmental concerns, there is a strong push to implement renewable energy sources. Renewable fuels and energies can play a crucial role in lowering GHG emissions and thus keeping the environment clean and green, which eventually meets the sustainability goals. Cellulosic ethanol in the USA and Brazil, biodiesel and biogas in Brazil and some European countries, and solar energy in India have shown promising growth. The carbon emissions of renewable fuels are very low compared to crude petroleum. This chapter compares the current scenario of biofuel implementation in various countries. Particular emphasis is placed on the current status of biogas development and commercialization. The carbon footprints of various biofuels/energies are also discussed.

Microfluidics is an interdisciplinary science dealing with the miniaturization of experiments with minimal expense, energy, time, and solvent usage. Experimental results are highly reproducible with great accuracy. Biodiesel is one of the prominent renewable biofuels, which has the potential to mitigate greenhouse gas emissions. In the biodiesel production process, algae cultivation, biomass harvesting, drying, lipid extraction, transesterification, and purification are significant steps. Microfluidics has shown prominent results not only in harvesting the biomass but also in efficient lipid extraction. Because of the advantage of miniaturization, using microfluidic devices is a viable approach for lipid extraction and biodiesel production. In this chapter, the basics of microfluidics and their applications in harvesting and extraction of lipids are elucidated.

Petroleum and oil field resources generate a significant amount of wastewater, which has the potential to infect water resources. Oil field wastewater contains a high amount of organic and inorganic pollutants, heavy oil complexes, surfactants, polymers, and their removal from the environment is the primary concern facing by the oil refinery. The petroleum waste and wastewater contain aliphatic and aromatic hydrocarbon, and their presence enormously impacts every aspect of the environment, human health, animals, and plants’ existence. This chapter explores the potential of bioelectrochemical systems along with other technologies for the treatment of petroleum and oil field wastewater. It also discusses the challenges and possible solutions faced by bioelectrochemical systems in treating wastewater.

Bioelectrochemical systems (BESs) have been intensively investigated over the last decade owing to its wide-scale environmentally friendly applications, among which wastewater treatment, power generation and environmental monitoring for pollutants are prominent. Different variants of BES such as microbial fuel cell, microbial electrolysis cell, microbial desalination cell, enzymatic fuel cell, microbial solar cell, have been studied. These microbial bioelectrocatalytic systems have clear advantages over the existing analytical techniques for sustainable on-site application in wide environmental conditions with minimum human intervention, making the technology irrevocable and economically feasible. The key challenges to establish this technology are to achieve stable and efficient interaction between the electrode surface and microorganisms, reduction of time for start-up and toxic-shock recovery, sensitivity improvement in real-time conditions, device miniaturization and its long-term economically feasible commercial application. This review article summarizes the recent technical progress regarding bio-electrocatalytic processes and the implementation of BESs as a biosensor for determining various compositional characteristics of water and wastewater.

This chapter discusses various types of bio-electro-chemical system, their application, highlighting majorly on wastewater treatment using Microbial Fuel Cells (MFC), and economic aspects of implementation of the technology at industrial scale. Various researches have been done at lab scale using synthetic organic substrate or model microbial consortia as catalyst for production of electricity in MFC. In a plant microbial fuel cell, the plant transfers its solar energy in the form of rhizospheric depositions, which are chemically sugars, polymeric carbohydrates, organic acids, dead cell material, and certain enzymes. In MFC, the chemical energy will be converted to electricity through the oxidation of biodegradable substrates with the help of exo-electrogenic bacteria. Various studies have been performed for the removal of ammonia and phosphate ions from the waste stream using MFC employed with ion exchange membrane. The MFC process was also compared to activated sludge process, and all the initial assessment shows that the MFC is a more attractive option.

A three-step purification of a unique lipase with halo-, solvent-, detergent-, and thermo-tolerance from Staphylococcus arlettae JPBW-1 gave raise to a 27-fold purification with a specific activity of 32.5 U/mg. The molecular weight of the purified lipase was estimated to be 45 kDa using SDS–PAGE, and its amino acid sequence was characterized using MALDI-TOF-MS analysis. The sequence obtained from MALDI-TOF-MS showed significant similarity with the capsular polysaccharide biosynthesis protein (CapD) of Staphylococcus aureus through comparative modeling approach using ROBETTA server. Identification of responsible fragments for homodimer formation was performed using comparative modeling and substrate binding domain through C-terminus matching of this new lipase with the CapD of Staphylococcus aureus was executed. Thus, the experimental coupled molecular modeling postulated a structure–activity relationship of lipase from S. arlettae JPBW-1, a potential candidate for detergent, leather, pulp, and paper industries.