Horizons in Bioprocess Engineering

Biodiesel is one of the several alternative fuels, which can be used without any modification in diesel engine. The nonedible Pongamia pinnata oil (PPO) possessing high free fatty acid (FFA) content has been investigated as a potential source of biodiesel production in the present study owing to its abundant availability in India. A two-step biodiesel production method can be employed via acid esterification of free fatty acids followed by base-catalyzed transesterification reaction. In the present study, the FFA of PPO is reduced to less than 1.5% and the process parameters of the esterification reaction have been investigated and optimized using Box–Behnken design (BBD) of response surface methodology (RSM) in lieu of Trial and Error method. The parametric effects of methanol to oil molar ratio, the catalyst concentration, and reaction time were investigated on acid value and yield %. The optimum conditions obtained from regression models were found to be 6.58:1 methanol to oil ratio, 2 wt% catalyst loading, and 2 h of time.

Caffeic acid bornyl ester (CABE) is a rare caffeic acid derivative and natural product with significant biological and pharmacological properties. Among the important properties are anti-inflammatory, antibacterial, anticancer, ability to inhibit HIV integrase, ability to induce apoptosis in breast cancer, and ability to treat leishmaniasis. CABE or also known as bornyl caffeate was initially extracted and isolated from plants. Afterward, several efforts were carried out to synthesize CABE using chemical extraction methods. However, the use of traditional chemical extraction and chemical synthesis method to produce CABE are uneconomical, inefficient, and toxic to human and environment. Enzymatic-catalyzed synthesis is a promising green reaction pathway for the synthesis of CABE and the most commonly used enzyme in the synthesis of ester is lipase. Lipases catalyze most of ester synthesis reactions such as esterification, transesterification and interesterification reactions in nonaqueous solvents. The versatility of lipases reaction in nonaqueous media has made them among the most important and potential biocatalysts for various industrial applications. In this chapter, the literatures related to the topic are reviewed starting with the importance of natural products followed by the introduction of CABE potential as natural product and how it is currently being synthesized. Then, a brief outline of enzymatic-catalyzed synthesis as a promising alternative method is emphasized. Subsequently, lipase-catalyzed synthesis of CABE was developed based on several related studies highlighted followed by the study on the effect of reaction parameters and the reaction mechanism.

Biodiesel, the alkyl esters of fatty acid is acquiring enormous attention in recent years and has been considered as one of the most promising renewable and sustainable energy resources to replace existing petroleum-derived diesel fuel. Among the various technologies available, the transesterification process exhibits huge potential for biodiesel production. Generally, different types of non-edible oils were utilized as feedstock to make the biodiesel production process more efficient and cost-effective. Hence, this review presents the potential of underutilized Calophyllum inophyllum oil (CIO) as a feedstock for biodiesel production. Moreover, the current study provides a detailed report about C. inophyllum oil and its physico-chemical properties. Furthermore, a detailed review of various biodiesel production techniques particularly transesterification process was presented. From the overall observations, it can be concluded that the non-edible C. inophyllum oil could be a potential and economical feedstock for biodiesel production.

The rapid exhaustion of fossil fuels and greenhouse effect leads to work on alternate energy and fuel source. In which, ethanol and methanol are widely discussed as an alternate for fuels over the decade. Fuels derived from the microbial biomass are one of the most promising renewable energy resources when compared to the conventional fuels from the petroleum reserves, which create excessive green gas emissions. The microbes are ubiquitous and many microbes are capable of converting the carbon source into primary metabolites, especially alcohols. Waste material generated from the industries like biodiesel, cassava, paper and pulp industries are rich in carbon and cellulose, which can be utilized by the microbes as carbon and energy source for the production of ethanol and methanol.

Major innovative breakthroughs in lignocellulose biotechnology offer significant opportunities for the utilization of agro-industrial residues like sugarcane bagasse, rice straw, corn stover into renewable fuels and biochemicals. Pretreatment is an inevitable and pivotal step to harness the sugars from the biomass effectively. These cellulosic sugars so-called second-generation (2G) are renewable and have the potential to replace conventional gasoline-derived chemicals and fuel, in a sustainable manner. However, the successful operation at large scale and production cost of cellulosic ethanol and renewable chemicals are two major concerns. Biomass conversion steps, i.e., pretreatment, large-scale enzymatic hydrolysis and fermentation, are critical and the cornerstone is the success of overall lignocellulose biorefineries. Only a handful of biomass pretreatment technologies such as a steam explosion, mild dilute acid pretreatment followed by a steam explosion, and ammonium hydroxide-mediated delignification is scalable and has the potential to be operated at the demonstration or commercial scale. Later, enzymatic hydrolysis using high total solids amounts (pretreated biomass) without any filtration and conditioning steps may provide economic sugars production. Each cellulosic ethanol producer has its technology as it largely depends on the feedstock and the operational conditions. Hence, the pretreatment conditions have to optimize by limiting the plant flexibility, which favors the handling of variant feedstocks in the same premise conditions. This situation necessitates the development of versatile pretreatments to process the variety of biomass feedstock using the minimum facilities and chemicals, eventually making process raw material independent. This chapter summarizes the recent developments made biomass processing (primary pretreatment methods, enzyme hydrolysis, fermentation, and distillation) into cellulosic ethanol.

During the past few decades, biofilm formation by a variety of microbial strains has attracted much attention, mainly in the medical and industrial settings due to their high resistance to antibiotics. However, environmental scientists and biochemical engineers have realized the importance of biofilm growth dynamics and their biocatalytic activity. For instance, the ability to forecast and control microbial communities has led to enhance biogas production and a better characterization of biofilm importance in wastewater treatment systems. Thus, understanding the fundamental processes contributing to biofilm growth is useful to anyone involved with natural or industrial settings where biofilms may play a significant role in determining variables such as bulk water quality, toxic compound biodegradation or product quality. Investigation of individual microcolonies within a biofilm using powerful microscopic tools has fueled the creation of biofilm models that reproduce biofilm growth dynamics and interactions. Mathematical frameworks that describe heterogeneous bacterial biofilms formation have greatly contributed to our understanding of physiochemical and biological principles of biofilm spreading dynamics. A clear understanding of heterogeneities at the local scale may be vital to solving the riddle of the complex nature of microbial communities, which is crucial to improve the performance, robustness and stability of biofilm-associated bioprocess.

Proteins are bio-macromolecules of long amino acid chains with several significant applications in living cells. It is the building block of tissues, enzymes, hormones, bones, muscles, cartilage, blood, skin and biological fluids. Proteins in biological fluids exist in combination with cells, DNA, RNA and other proteins. This requires effective separation and purification mechanisms to detect, isolate and characterize specific proteins from biological fluids. Numerous conventional methods are available for separation, purification and detection of proteins. However, these methods are challenged with several drawbacks including low separation efficiency, low purity levels, use of complex separation and purification processes, requirement of stringent purification steps, and lower detection sensitivity in complex biofluids. Application of nanoparticles presents a strategy to address the challenges associated with protein separation, purification and detection. This is due to the unique properties of nanoparticles including enhanced surface area to volume ratio, presence of atoms at the edges of surface, enhanced bioactivity and sensitivity. This chapter presents an overview of different types of nanoparticles used for protein separation, purification and detection applications. In addition, accounts on industrial applications of nanoparticles for protein bioseparation and future reflections are discussed.

Crude glycerol generated as by-product in transesterification and saponification process in biodiesel and soap industries. The wide application of crude glycerol was restricted by the presence of a copious amount of impurities such as water, methanol, soap, fatty acid, and ash. A simple way of utilizing the surplus amount of glycerol generated in biodiesel industries is to convert them in the valuable product either by fermentation, esterification, hydrogenolysis, dehydration, oxidation, and liquefaction. Utilizing crude glycerol as feedstock for the production of valuable products through biological conversion is more reliable and safer when compared to other methods. Apart from the conventional products like ethanol, citric acid, 1, 3, propanediol, crude glycerol can also use for the production of biosurfactants, pigments, mannitol, biohydrogen.

The continuous dependence on the non-renewable fossil fuel could result in diminishing petroleum reserves and environmental degradation in times to come. Early steps to avert this is by developing an alternative fuel of good quality and eco-friendly that is compatible with the existing car engines. Hence, this study evaluates the efficiency of Cu/ZSM-5 catalyst in promoting gasoline range hydrocarbons for the catalytic cracking of refined rubber seed oil. The parametric conditions such as temperature (350–500 ℃) and weight hour space velocity, WHSV (1–4 h⁻¹) were optimised using Response Surface Methodology Design (RSM) in a fixed-bed reactor at atmospheric condition. The aim of the optimisation study was to achieve a balance between productivity, fuel quality and environment security. Therefore, the optimal operating conditions were achieved at temperature of 440 ℃ and WHSV of 1.7 h⁻¹ producing paraffin, isoparaffin and aromatics distribution of 6.42%, 1.67% and 78.1%, respectively, with 91.7% of conversion and 49.67% of gasoline selectivity.

Society demands for a sustainable production of chemicals, polymers integrated biorefinery and biofuels. It is estimated that lignocellulosic biomass can be an alternative to replace oil as a primary feedstock. Furfural has the advantage of being already a commercial reality and more interestingly, a myriad of many others, including biofuels, has been reported to be technically possible. This book chapter entitled “Furfural—A Promising symbiotic business model for Integrated biorefinery” is aimed at to serve to a wide cross section of readers, including industrial professional, policymakers, academic researchers and also beginners in the world of the furfural proceeses and products. A brief details about Furfural structure, physical properties and synthesis, Furfural products and applications, Future Prospects and Challenges are outlined in the chronlogical order. Further, a Furfural Consortium business symbiotic model is proposed based on interactive deliberations with all the stakeholders of the society.

In the commercial exploitation of lignocellulosics for biofuels and other value-added chemicals, the biomass is enzymatically degraded to C5 and C6 sugars for further processing to preferred products of choice. But the economics of bioprocessing of biomass is limited by the cost of biocatalysts employed for the hydrolysis of lignocellulosic polymer to sugar monomers besides a corollary of other factors. Therefore, commercialization of these biocatalytic processes still needs various refinements in the existing infrastructure of lignocellulosic biorefinery. This chapter brings together and discusses better strategies to advance the enzymatic hydrolysis, the characteristics of the components involved (substrate and catalysts), substrate–catalyst complex, and its influence on the overall saccharification performance. Further, it also discusses the diversity of microbial-derived cellulases and their synergism for the effective sugar recovery from cellulose.

The production of recombinant proteins using genetically engineered microbes are well known. However, integrating systems biology approach such as network-based modeling have enabled to identify all possible pathways that can be rationally engineered to improve protein production and also to reduce the by-product accumulation. Furthermore, by utilizing the insilico systems biology tools, the pathway editing can be easily carried out. Recently the exploration of genome engineering using CRISPR Cas9 technology has enhanced the foreign gene integration as well gene deletion in the genome of several cell factories. Hence, with the systems biology tool and synthetic biology approach superior organism can be created, which has ability to produce the recombinant protein in the range of grams per liter. In the present book chapter, we have discussed the constraint-based methods, which can be used for strain improvement. Further, we have briefly described the in vivo gene manipulation techniques used for bacteria as well as yeast system.

Bioethanol is a form of renewable energy produced from carbohydrate-rich feedstocks. Bioethanol can be generated from universally available crops like hemp, sugarcane, cassava, corn, wheat crops, waste straw, sawdust, etc. It is mostly used as a motor fuel, an additive for gasoline. The blending of bioethanol with petrol helps in overcoming the problems of declining oil supply due to diminishing fossil fuels. Lignocellulosic materials are converted into fermentable sugars by saccharification using cellulase enzyme. The use of free cellulase leads to the loss of enzyme and makes the process expensive. The use of immobilized enzyme is an effective way to obtain stable and reusable enzymes with resistance to different environmental parameters. Immobilization cellulase on nanoparticles improves enzymatic activity due to the synergistic effect of cellulose with certain nanomaterials and enhances stability, reusability, increase in catalytic properties, and limitation of microbial growth. Further liberated glucose can be converted to ethanol by fermentation using free or immobilized yeast cells. The use lignocellulosic materials for bioethanol production will help to reduce the urban waste disposal problem and meet the energy demand in the near future. Thus, the immobilization strategy could improve the bioethanol production economically and commercialized for enhanced bioethanol production.

Biotechnology relevant to gold exploration, mining, recovery, and waste disposal is illustrated with respect to microbiological aspects of gold mineralization, biooxidation of refractory sulfide ores and concentrates, cyanide-free gold dissolution, and biodegradation of cyanide containing effluents. Current industrial status of technological innovations in the bioreactor processing and heap bioleaching of refractory sulfide ores and concentrates are discussed. Biodetoxification and degradation of cyanides in waste tailings and waters are critically analyzed with examples from industrial practice. Prospects for direct biodissolution of gold are brought out. Recovery of gold from spent leach cyanide solutions and electronics wastes is examined. Bright future prospects for biotechnology in gold exploration, mining, extraction, and waste disposal are emphasized.

The organic wastewaters emanated from industries and domestic sources if discharged to inland surface waters without proper treatment, will lead to damage of the environment. In order to protect environment, it is essential to treat these wastewaters originating from industrial or domestic sources by physical, chemical or biological methods. Since the composition of wastewaters is not uniform and complex in nature, biowaste treatment seems to be an economically viable solution. Certain organic chemical wastewaters are difficult to biodegrade and such wastewaters are considered to be recalcitrant. Nitroaromatic plant wastewaters fall under recalcitrant category of wastes. The acclimatization period of nitroaromatic wastewaters would be 4–6 weeks. Biowaste treatment takes an important role in treating various types of organic chemical industrial wastewaters and domestic wastewaters. Biological wastewater treatment can be either aerobic or anaerobic in nature. These microorganisms may be strict aerobes or anaerobes or could be facultative. Nevertheless biowaste treatment plays a key role in wastewater treatment system. Some organic industrial wastewaters can be easily treated so that the final biochemical oxygen demand (BOD) is almost zero. Interestingly certain recalcitrant organic compounds like nitroaromatic compounds are difficult to be degraded by aerobic bacteria. Even these recalcitrant compounds are treated by aerobic microorganisms after proper acclimatization and finally the treated wastewater contains simpler organic compounds that could be nontoxic in nature. Essentially the benzene ring is broken to simpler compounds like pyruvate and the treated wastewater can be discharged to inland surface water streams. Further the treated wastewater is subjected to bioassay test, so as to confirm its nontoxic nature. The fundamental concepts of the aerobic and anaerobic treatment along with a case study of nitroaromatic plant wastewaters are discussed in this chapter.

Industrial bioprocess engineering is an aggregation of chemistry, biology, mathematics and industrial design that particularly deals with various biotechnological processes employed in large-scale production in bio-related industries. It applies the principles of physics, chemistry and other allied disciplines of engineering to design and mimics the entities and processes close to nature. Since they deal with nature-like entities and processes which are not obviously natural and have potential novelty and utility aspects, they inherently qualify for protection by way of intellectual property rights enabling the first time manufacturers an opportunity to enjoy the fruits of hard work, time and monetary investments for a stipulated period of time and to further exclude others to exploit the results and products without their permission. These rights are territorial in nature, therefore, a potential invention has to be reviewed keenly towards protection on intellectual property terms in accordance with the domestic and international regulations for widespread societal acceptance and exclusivities without compromising on the quality. The international agencies such as the World Intellectual Property Organization strive hard in harmonizing the intellectual property related rules that are acceptable by all for fair trade and negotiations at global levels, supported by the national framework of each nation.

The need of the hour is to maintain a dynamic equilibrium between man and universe for sustainable life. There is an urgent necessity in providing humanity with new materials and clean energy in a sustainable way. In other words, it is the integration of environment, energy, equity and economy which is known as Green Technology. This will require more efficient and entirely different use of natural resources such as abundantly available lignocellulose biomass waste. Novel synthesis routes for integrated bio refinery plants will have to be developed in which waste streams can be converted into essential fuel and chemical streams to fulfill the needs of the society. The development of new manufacturing processes critically depends on the rational design and development of new catalysts. Catalytic materials accelerate and facilitate the conversion of raw materials into products at milder process conditions and with reduced energy consumptions. However, traditionally, catalyst development is still carried out using trial-and-error methods, few empirical models (Nolan et al. in Nature Catalysis, 2018), which are slow, undirected and unreliable. The perspective is toward exploiting waste biomass resources, to design and develop a rational catalyst and efficient transfer learning approach for integrated biorefinery applications. Combine hybrid models, machine learning algorithms and high-throughput experimentation are studied in the past and provide the enabling factors for new material and energy streams to have ‘plenty for all and perennially’ (https://​www.​ncl.​ac.​uk/​).