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The inefficient food processing and food leftover management strategies often lead to the wastage of untapped carbohydrate-rich feedstocks. The conversion of these feedstocks into bioethanol can mitigate the emission of greenhouse gases (GHGs) while providing a sustainable and eco-friendly method for disposing of food wastes. In light of the above, the current review scrutinizes various types of food wastes (homogeneous and heterogeneous) and pretreatment methods (physical, chemical, physicochemical, and biological) for their valorization into bioethanol. The main constraints to commercial production of food-waste-derived bioethanol, that is, the requirement for sterilization and collection of feedstocks, are also discussed. The former issue can be addressed by developing an optimized solid-state fermentation process. Employing selective conditions to enrich bioethanol-producing microorganisms can increase the feasibility of this process configuration while inhibiting ethanol-consuming strains. The feedstock collection issue can be minimized by determining the hot spots that are in the vicinity of the large food processing sites.

This study reviews the innovations and optimizations in biogas production from the biological perspective reported by recently published patents and research works. The proposed biological strategies can be categorized into three different groups, i.e., upstream, mainstream, and downstream approaches. In the first part of this review, upstream strategies, including pretreatments by fungal, microbial consortium, and enzymatic as well as some other biological methods including microaeration, composting, ensiling, and genetic and metabolic engineering are discussed in detail. The impacts of upstream strategies on biogas production as well as their potentials in further improving the biogas industry are comprehensively scrutinized. Despite their promising impacts on biogas production, such biological innovations are time-consuming and require extra equipment and facilities that should be addressed in future studies. Overall, most information on biogas production has been generated through lab-scale investigations and not by commercial plants, undermining the commercial value of these data for the right decision-making. Pilot data would be necessary for techno-economic analyses with acceptable accuracies. Therefore, the future efforts should be directed toward providing the missing data for re-engineering designs, calculations, and life cycle assessment (LCA) of the newly designed biogas plants.

This review is aimed at detailing and discussing biological innovations and optimizations including upstream, mainstream, and downstream approaches in biogas production elaborated in the recently published patents and research papers. In the first part of this review, upstream strategies including pretreatments by fungal, microbial consortium, and enzymatic as well as some other biological methods including microaeration, composting, ensiling, and genetic and metabolic engineering were comprehensively presented and duly discussed. Despite the fact that these approaches hold great promise for improving the quantity and quality of the evolved biogas, the need for more processing time and extra equipment are the main drawbacks of such strategies. In the second part of this review, mainstream and downstream strategies are reviewed, and their merits and limitations are outlined. Bioaugmentation, anaerobic co-digestion, and integrated biogas production are evaluated as mainstream strategies. Finally, downstream biological approaches used for removal of CO2, H2S, and other impurities are reviewed and discussed. Among the mainstream biological techniques, bioaugmentation is highly advised to accelerate start-up periods at commercial scale while anaerobic co-digestion is recommended to not only enhance biogas yield throughout the operation but also to take advantage of different waste streams. Such mainstream strategies could contribute to improving the economic facets of biogas plants. Despite their currently underdeveloped status, downstream techniques for biological removal of biogas impurities are expected to replace their physiochemical counterparts at industrial scale in future owing to increasingly stringent environmental regulations.

It is obvious that Iran agricultural industry, unlike Brazil and USA, cannot afford to provide conventional biomass, i.e. sugary or starchy biomass for bioethanol production, mainly due to climatic and geographic conditions. With some exception of date (fruit), first-generation ethanol production triggers food vs. fuel debates in Iran and put nation to hunger. Agricultural products including apple, barley, carrot, corn, grape, orange, potato, rice, sugar beet, sugarcane, and wheat are consumed domestically, exported, or even lost because of poor harvesting and processing conditions such as transportation or packaging. These products may alone generate 21.56 million ton per annum green wastes upon processing in the food industry. Every year about 5.4 billion liters of bioethanol can be produced by establishing second-generation ethanol plants next to the food processing sectors. Seventy-seven-percent of this amount of bioethanol can easily support 5% ethanol (E5) policy to phase out the consumption of 4.2 billion liters methyl tert-butyl ether (MTBE) for raising the octane number of gasoline in the country. If more comprehensive policy is adopted, larger quantities of lignocellulosic feedstocks can be gathered from agro as well as forestry practices. Second-generation bioethanol technology can help Iran to tackle air pollution in its big cities and to address the adverse effects of MTBE on its populations and ecosystem. The other advantages are improvement of fuel security, mitigation of climate change, and development of economy. The motivation can be created through passing a framework policy to cut fossil fuel subsidies, to mandate bioethanol blends in gasoline, and to impose carbon taxes. Development of coherent socially and environmentally relevant strategies and facilitation of investment in bioethanol industry are also necessary.

Anaerobic fungi (Neocallimastigomycota) are promising lignocellulose-degrading microorganisms that can be exploited by the biofuel industry. While natural production of ethanol by these microorganisms is very low, there is a greater potential for their use in the biogas industry. More specifically, anaerobic fungi can contribute to biogas production by either releasing holocellulose or reducing sugars from lignocelluloses that can be used as a substrate by bacteria and methanogens involved in the anaerobic digestion (AD) process or by metabolizing acetate and formate that can be directly consumed by methanogens. Despite their great potential, the appropriate tools for engineering anaerobic fungi have not been established yet. The first section of this review justifies how the biofuel industry can benefit from using anaerobic fungi and is followed by their taxonomy. In the third section, the possibility of using anaerobic fungi for the consolidated production of bioethanol is briefly discussed. Nevertheless, the main focus of this review is on the upstream and mainstream effects of bioaugmentation with anaerobic fungi on the AD process. The present review also scrutinizes the constraints on the way of efficient engineering of anaerobic rumen fungi. By providing this knowledge, this review aims to help research in this field with identifying the challenges that must be addressed by future experiments to achieve the full potentials of these promising microorganisms. To sum up, the pretreatment of lignocelluloses by anaerobic fungi can prevent carbohydrate loss due to respiration (compared to white-rot fungi). Following fungal mixed acid fermentation, the obtained slurry containing sugars and more susceptible holocellulose can be directly consumed by AD microorganisms (bacteria, methanogens). The bioaugmentation of anaerobic fungi into the AD process can increase methane biosynthesis by3.3 times. Despite this, for the commercial AD process, novel genetic engineering techniques and kits must be developed to efficiently improve anaerobic fungi viability throughout the AD process.

Appropriate bioprocessing of lignocellulosic materials into ethanol could address the world’s insatiable appetite for energy while mitigating greenhouse gases. Bioethanol is an ideal gasoline extender and is widely used in many countries in blended form with gasoline at specific ratios to improve fuel characteristics and engine performance. Although the bioethanol production industry has long been operational, finding a suitable microbial agent for the efficient conversion of lignocelluloses is still an active field of study. Among available microbial candidates, engineered bacteria may be promising ethanol producers while may show other desired traits such as thermophilic nature and high ethanol tolerance. This review provides the current knowledge on the introduction, overexpression, and deletion of the genes that have been performed in bacterial hosts to achieve higher ethanol yield, production rate and titer, and tolerance. The constraints and possible solutions and economic feasibility of the processes utilizing such engineered strains are also discussed.

Liquid transportation biofuel production is a promising strategy to reduce greenhouse gas emissions. Hydrothermal gasification (HTG) has shown great potential as an effective method for valorizing wet biomass. The high-quality syngas produced using the HTG process can be chemically/biochemically converted to liquid biofuels. Therefore, this paper aims to comprehensively review and critically discuss syngas production from biomass using the HTG process and its conversion into liquid biofuels. The basics and mechanisms of biomass HTG processing are first detailed to provide a comprehensive and deep understanding of the process. Second, the effects of the main operating parameters on the performance of the HTG process are numerically analyzed and mechanistically discussed. The syngas cleaning/conditioning and Fischer-Tropsch (FT) synthesis are then detailed, aiming to produce liquid biofuels. The economic performance and environmental impacts of liquid biofuels using the HTG-FT route are evaluated. Finally, the challenges and prospects for future development in this field are presented. Overall, the maximum total gas yield in the HTG process is obtained at temperature, pressure, and residence time in the range of 450–500 °C, 28–30 MPa, and 30–60 min, respectively. The highest C5+ liquid hydrocarbon selectivity in the FT process is achieved at temperatures between 200 and 240 °C. Generally, effective conversion of biomass to syngas using the HTG process and its successful upgrading using the FT process can offer a viable route for producing liquid biofuels. Future studies should use HTG technology in the biorefinery context to maximize biomass valorization and minimize waste generation.

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a serious, complex, and highly debilitating long-term illness. People with ME/CFS are typically unable to carry out their routine activities. Key hallmarks of the disease are neurological and gastrointestinal impairments accompanied by pervasive malaise that is exacerbated after physical and/or mental activity. Currently, there is no validated cure of biomarker signature for this illness. Impaired tryptophan (TRYP) metabolism is thought to play significant role in the pathobiology of ME/CFS. TRYP is an important precursor for serotonin and the essential pyridine nucleotide nicotinamide adenine dinucleotide (NAD

The incidence of neurodegenerative diseases and cyanobacterial blooms is concomitantly increasing worldwide. The cyanotoxin β-N-methylamino-L-alanine (BMAA) is produced by most of the Cyanobacteria spp. This cyanotoxin is described as a potential environmental etiology factor for some sporadic neurodegenerative diseases. Climate change and eutrophication significantly increase the frequency and intensity of cyanobacterial bloom in water bodies. This review evaluates different neuropathological mechanisms of BMAA at molecular and cellular levels and compares the related studies to provide some useful recommendations. Additionally, the structure and properties of BMAA as well as its microbial origin, especially by gut bacteria, are also briefly covered. Unlike previous reviews, we hypothesize the possible neurotoxic mechanism of BMAA through iron overload. We also discuss the involvement of BMAA in excitotoxicity, TAR DNA-binding protein 43 (TDP-43) translocation and accumulation, tauopathy, and other protein misincorporation and misfolding.

Environmental deterioration, global climate change, and consequent increases in pollution-related health problems among populations have been attributed to growing consumption of fossil fuels in particular by the transportation sector. Hence, replacing these energy carriers, also known as major contributors of greenhouse gas emissions, with biofuels have been regarded as a solution to mitigate the above-mentioned challenges. On the other hand, efforts have been put into limiting the utilization of edible feedstocks for biofuels production, i.e., first generation biofuels, by promoting higher generations of these eco-friendly alternatives. In light of that, the present review is aimed at comprehensively assessing the role and importance of microorganisms such as bacteria and yeasts as catalysts for sustainable production of liquid biofuels including bioethanol, biomethanol, biobutanol, bio-ammonia, biokerosene, and bioglycerol. Various aspects of these biofuels, i.e., background, chemical synthesis, microbial production (including exploitation of wild and metabolically-engineered species), and product recovery as well as the derivatives produced from these biofuels which are used as fuel additives are thoroughly covered and critically discussed. Furthermore, the industrial features of these green liquid fuels including the industrial practices reported in the literature and the challenges faced as well as possible approaches to enhance these practices are presented.

Finding renewable alternative energy resources for fossil fuels substitution has become very vital due to the serious challenges faced by humankind at present such as environmental pollution, greenhouse gas emissions, climate change, crude oil price volatility, and fossil fuels exhaustion. Macroalgae (seaweeds) are fast-growing marine plants, providing several harvests per year without the need for arable land, fertilizer, and fresh water. Various types of ecosystems like coral reefs, mangrove forests, and rocky shores can efficiently host the seaweeds production systems. These characteristics have made them highly suitable feedstocks for third-generation bioethanol production. Iran has a huge potential in renewable energy resources owing to its unique geographical location and climatic features. The country borders with the Caspian Sea in the north and with the Persian Gulf and the Gulf of Oman in the south. Seaweeds farming can also play a key role in mitigating air pollution, increasing employment rate, sustaining fossil fuel resources, bioremediating contaminated water, and improving marine ecosystem in the Persian Gulf and the Gulf of Oman. In the present article, macroalgae diversity, cultivation, and their conversion and upgrading technologies into bioethanol in Iran are scrutinized and discussed. Finally, the potential of Bushehr (the Persian Gulf) and Chabahar (the Gulf of Oman) coastlines for macroalgae cultivation is investigated. These locations receive the annual solar radiation in the range of 1680‒1753 kWh/m2 and the photosynthetically active radiation (PAR) in the range of 2.6‒2.71 GJ/m2/year with 3051‒3311.9 h sunshine per annum. Furthermore, the nutrient-rich and calm water with relatively stable pH, salinity, and temperature make these coasts suitable for macroalgae farming. A potential yield up to 147‒153 t/ha/year can be obtained if proper native/engineered species, well-situated sites, and compatible cultivation techniques are selected.

Agricultural and livestock/slaughterhouse wastes are produced in huge quantities and could be promising sources for electricity generation to partially reduce dependence on fossil-oriented electricity. In light of that, the state of the production for these wastes in different parts of the globe was first presented. Subsequently, various waste-to-energy technologies and their electricity generation feasibility from both environmental and economic perspectives were reviewed. Finally, electricity generation and greenhouse gas (GHG) reduction potentials through anaerobic digestion of the above-mentioned wastes generated in each province of Iran in 2016 were investigated as a case study. Accordingly, Khuzestan province with the highest amount of agro-wastes (7.61 million tons) and Sistan and Baluchestan province with the highest amount of livestock/slaughterhouse wastes (10.69 million tons) had the maximum electricity generation potentials of 82.83 MW and 164.23 MW, respectively. Moreover, the country's total potentials for electricity generation from these wastes was determined at 2848.26 MW. Based on the life cycle assessment (LCA) results, a minimum of 10,693.5 thousand tons CO2eq/yr could be avoided by valorizing these wastes into electricity in Iran. This would be translated into 1.5% reduction of Iran's annual GHG emissions; a promising achievement given Iran's international GHGs reduction commitment. Moreover, if a short-term time horizon would be considered for electricity generation from these wastes, the reduction rate could reach 24,153 thousand tons CO2eq/yr, i.e., 3.39% reduction of Iran's annual GHG emissions. To the best of our knowledge, this is the first report scrutinizing electricity generation potentials from both agricultural and livestock/slaughterhouse wastes in Iran while assessing the consequent GHG emission reduction potentials. The outcomes of the study could assist policy makers with decisions aimed at taking advantage of these resources while the platform introduced pave the way for other researchers to conduct similar studies in different parts of the world.

Diesel engines are preferred over spark ignition counterparts for heavy-duty applications and power generation plants because of their higher efficiency, durability, and productivity. Currently, the research interests have been propelled towards renewable and sustainable diesel fuels such as biodiesel in order to address the environmental and energy security challenges associated with these energy systems. However, the most challenging issue concerning large-scale production of biodiesel is its relatively high cost over fossil-based diesel owing to high feedstock and manufacturing costs. Therefore, cost-effective and eco-friendly biodiesel production technologies should be necessarily developed and continuously improved in order to make this biofuel more competitive vs. its petroleum counterpart. Accordingly, this paper comprehensively reviews biodiesel manufacturing techniques from natural oils and fats using conventional and advanced technologies with an in-depth state-of-the-art focus on the utmost important unit, i.e., transesterification reactor. The effects of the main influential parameters on the transesterification process are first discussed in detail in order to better understand the mechanisms behind each reactor technology. Different transesterification reactors; e.g., tubular/plug-flow reactors, rotating reactors, simultaneous reaction-separation reactors, cavitational reactors, and microwave reactors are then scrutinized from the scientific and practical viewpoints. Merits and limitations of each reactor technology for biodiesel production are highlighted to guide future R&D on this topic. At the end of the paper, the sustainability aspects of biodiesel production are comprehensively discussed by emphasizing on the biorefinery concept utilizing waste-oriented oils.

Human livelihood highly depends on applying different sources of energy whose utilization is associated with air pollution. On the other hand, air pollution may be associated with glioblastoma multiforme (GBM) development. Unlike other environmental causes of cancer (e.g., irradiation), air pollution cannot efficiently be controlled by geographical borders, regulations, and policies. The unavoidable exposure to air pollution can modify cancer incidence and mortality. GBM treatment with chemotherapy or even its surgical removal has proven insufficient (100% recurrence rate; patient’s survival mean of 15 months; 90% fatality within five years) due to glioma infiltrative and migratory capacities. Given the barrage of attention and research investments currently plowed into next-generation cancer therapy, oncolytic viruses are perhaps the most vigorously pursued. Provision of an insight into the current state of the research and future direction is essential for stimulating new ideas with the potentials of filling research gaps. This review manuscript aims to overview types of brain cancer, their burden, and different causative agents. It also describes why air pollution is becoming a concerning factor. The different opinions on the association of air pollution with brain cancer are reviewed. It tries to address the significant controversy in this field by hypothesizing the air-pollution-brain-cancer association via inflammation and atopic conditions. The last section of this review deals with the oncolytic viruses, which have been used in, or are still under clinical trials for GBM treatment. Engineered adenoviruses (i.e., DNX-2401, DNX-2440, CRAd8-S-pk7 loaded Neural stem cells), herpes simplex virus type 1 (i.e., HSV-1 C134, HSV-1 rQNestin34.5v.2, HSV-1 G207, HSV-1 M032), measles virus (i.e., MV-CEA), parvovirus (i.e., ParvOryx), poliovirus (i.e., Poliovirus PVSRIPO), reovirus (i.e., pelareorep), moloney murine leukemia virus (i.e., Toca 511 vector), and vaccinia virus (i.e., vaccinia virus TG6002) as possible life-changing alleviations for GBM have been discussed. To the best of our knowledge, this review is the first review that comprehensively discusses both (i) the negative/positive association of air pollution with GBM; and (ii) the application of oncolytic viruses for GBM, including the most recent advances and clinical trials. It is also the first review that addresses the controversies over air pollution and brain cancer association. We believe that the article will significantly appeal to a broad readership of virologists, oncologists, neurologists, environmentalists, and those who work in the field of (bio)energy. Policymakers may also use it to establish better health policies and regulations about air pollution and (bio)fuels exploration, production, and consumption.

This expert opinion focuses on the impact of global warming and climate change on the spread and distribution of Australian ticks and the prevalence and intensity of associated human diseases.

Background The accumulation of extracellular plaques containing amyloid-β protein (Aβ) in the brain is one of the main pathological hallmarks of Alzheimer's disease (AD). Aβ peptide can promote the production of highly volatile free radicals and reactive oxygen species (ROS) that can induce oxidative damage to neurons and astrocytes. At present, numerous studies have investigated the neuroprotective and glioprotective effects of natural products derived from plants, animals, and microorganisms. Objective We investigated the glioprotective effect of secondary metabolites obtained from Herpetosiphon sp. HM 1988 against Aβ40-induced toxicity in human primary astrocytes. Methods The protective effect of bacterial secondary metabolites against Aβ40-induced inducible nitric oxide synthase (iNOS) activity was evaluated using the citrulline assay. To confirm the iNOS activity, nitrite production was assessed using the fluorometric Griess diazotization assay. Intracellular NAD+ depletion and lactate dehydrogenase (LDH) release in human primary astrocytes were also examined using well-established spectrophotometric assays. Results Our results indicate that Aβ40 can induce elevation in iNOS and LDH activities, nitrite production, and cellular energy depletion. Importantly, extract of Herpetosiphon sp. HM 1988 decreased iNOS activity, nitrite production, and LDH release. In addition, metabolites of the strain were able to restore cellular energy deficits through inhibition of NAD+ depletion mediated by Aβ40. Conclusion These findings suggest that Herpetosiphon metabolites may represent a promising, novel source for the prevention of Aβ toxicity in AD.

Currently, the modern world is facing with a major challenge regarding the production of renewable energy for phasing out fossil fuels. Lignocellulosic biomass can potentially be used as a substrate for the production of a diverse range of different biofuels such as bioethanol while not triggering food vs. fuel debate. Generally, the bioethanol production from lignocellulosic biomass involves four major steps including lignocellulose delignification/pretreatment, hydrolysis (i.e., chemical or enzymatic), hydrolyzate sugar fermentation, and distillation. The economic and environmental feasibilities of the mentioned process could significantly be enhanced through the application of phytopathogenic fungi or their enzyme cocktails. Typically, necrotrophic pathogenic fungi have exceptionally high capabilities for a copious production of various hydrolytic enzymes with activity on wide range of plant biomass, compared to biotrophic or hemibiotrophic ones. In this chapter, ten filamentous plant-pathogenic fungi species belonging to six genera, including Fusarium, Aspergillus, Phoma, Cryphonectria, Ustilago, and Colletotrichum, have comprehensively been discussed in respect to hydrolytic enzyme capabilities from bioethanol industry viewpoint. On this basis, their potential for application in simultaneous saccharification and fermentation (or co-fermentation), separate hydrolysis and fermentation, and consolidated bioprocessing process has been investigated. Eventually, their genome richness in respect to the construction of lignocellulose-degrading microorganisms or ethanologens with astonishing hydrolysis production ability from these fungi has also been scrutinized.

Among many alternatives, biodiesel is considered as one of the most promising biofuels for phasing out fossil-derived fuels and mitigating their adverse ecological impacts. However, conventional alkali- or acid-catalyzed transesterification of plant oils triggers food security, economic, and even environmental (e.g., land-use change and greenhouse gas emissions) challenges. In contrast, advanced biodiesel (i.e., second-generation biodiesel) could be synthesized from oleaginous microorganisms such as fungal and yeast. The most oleaginous fungal genera are Alternaria, Aspergillus, Chaetomium, Colletotrichum, Cunninghamella, Epicoccum, Mortierella, Mucor, Thamnidium, and Zygorhynchus. On the other hand, Yarrowia, Candida, Rhodotorula, Rhodosporidium, Aureobasidium, Cryptococcus, Metschnikowia, Kodamaea, Trichosporon, Sporidiobolus, Sporobolomyces, Occultifur, Starmerella, Pichia, and Lipomyces are the most common oleaginous yeast genera. Typically, the main lipid classes produced by oleaginous fungi and yeasts are polyunsaturated fatty acids (PUFAs, such as arachidonic acid, c-linolenic acid, dihomo-γ-linolenic acid, docosahexaenoic acid, and eicosapentanoic acid) and triglycerides (TGs) and sterol esters (SEs), respectively. Alternatively, oleaginous yeast or fungal-origin lipases could be exploited in biodiesel production via enzymatic transesterification approach. It is worth mentioning that the most widely used lipases in biodiesel industry are those extracted from yeasts (e.g., Candida antarctica and Candida rugosa) and filamentous fungi (e.g., Aspergillus niger, Penicillium expansum, Rhizomucor miehei, Rhizopus oryzae, and Thermomyces lanuginosus). In this chapter, the current status for the application of different single-cell oil (SCO)-producing filamentous fungi and yeast species is scrutinized in the first part. Same section also deals with some technological strategies for reducing SCO production cost with a particular attention on the abilities of these microorganisms for assimilating different organic wastes. In the second part of the chapter, yeast and fungal lipases as biocatalyst for biodiesel production are discussed. Overall, despite some improvements, further research in this field with respect to identification of novel oleaginous microorganisms (with high lipase and/or lipid content) as well as development of more efficient technologies (microbial fermentation, oil extraction, and biodiesel production) must be conducted to address some techno-economic constraints of SCO-based biodiesel industry.

Fossil fuels and chemical pesticides could probably be blamed for future human downfall. Therefore, the global dependence on fossil fuels must be reduced immediately due to climate change, environmental issues, and health complications. The latter two negative effects could also be rendered by chemical pesticides. Among renewable energy alternatives, liquid biofuels have higher compatibility with the current fuel infrastructures and engines (i.e., transportation, storage, and engine systems), and hence, are very promising for transportation sector. Bioethanol, a liquid biofuel, is an ideal gasoline extender and is widely used in many countries in blended form with gasoline at specific ratios to improve fuel characteristics and engine performance. Although the bioethanol production industry has long been operational, finding suitable and sustainable feedstock is still an active field of study. The consumption of food/feed commodities such as sugarcane and corn (i.e., the first-generation bioethanol) has raised food vs. fuel debate. Alternatively, scientists have concentrated on the second-generation bioethanol, which consumes wastes such as lignocelluloses. However, huge amounts of hydrolytic enzymes, particularly cellulases, are required that contribute to high bioethanol production cost. Fungal biocontrol agents are superb producers of these enzymes, while at the same time they could be used as effective biological pesticides for sustainable agriculture. In this chapter, a novel viewpoint is put forward for sustainable direct production of bioethanol from lignocellulose by fungi, which could easily be separated at the end of the process and be exploited as biological control agents. For this purpose, several promising species within Fusarium, Paecilomyces, Pichia, and Trichoderma along with two species including Aspergillus oryzae and Pochonia chlamydosporia are comprehensively evaluated and scrutinized. The characteristics of these fungi could be further improved and harnessed for a dual production of biocontrol agents and bioethanol, improving the economic and environmental feasibilities of lignocellulose-based bioethanol production.

The appropriate processing of various plant biomass residues into biofuels could address the world’s insatiable appetite for energy. To achieve such a goal, an efficient and ecofriendly pretreatment method to break the lignocellulosic materials into fermentable sugars is pivotal. Among various candidate methods, anaerobic gut fungi could provide economic and efficient hydrolytic enzymes for biological pretreatment of lignocellulosic constituents (excluding lignin). The present chapter provides an insight into the taxonomy, life cycle, cultivation, isolation, and preservation of Neocallimastigomycota. Thereafter, the interaction between these fungi and other microorganisms in their natural ecosystem (i.e., rumen) is reviewed while discussing anaerobic gut fungal hydrolytic enzymes (recombinant enzymes included) for biomass degradation. Then, the main focus is placed on the potential application of this phylum of fungi for biofuel (ethanol and biogas) production. Overall, the efficiency of Neocallimastigomycota for biological pretreatment of plant biomass for bioethanol or biogas production has been overlooked. Anaerobic nature (compatible with ethanol and anaerobic digestion process), high enzyme production capabilities, fast and easy cultivation, and ecofriendly nature are some of the advantages of these fungi that could be exploited for higher economic profitability of the biofuel industry.

Aim: To simplify the recognition of Actinobacteria, at different stages of the growth phase, from a mixed culture to facilitate the isolation of novel strains of these bacteria for drug discovery purposes. Materials & methods: A method was developed based on Gabor transform, and machine learning using k-Nearest Neighbors and Naive Bayes classifier, Logitboost, Bagging and Random Forest to automatically categorize the colonies. Results: A signature pattern was inferred by the model, making the differentiation of identical strains possible. Additionally, higher performance, compared with other classification methods was achieved. Conclusion: This automated approach can contribute to the acceleration of the drug discovery process while it simultaneously can diminish the loss of budget due to the redundancy occurred by the inexperienced researchers.

Gasoline is currently the main fuel of choice in many cities worldwide, and hence, the consequent exposure to its emissions, i.e., CO, NOX, unreacted hydrocarbons, particulate matters, lead, sulfur dioxide, and ozone, is inevitable. Among the various solutions put forth to mitigate the toxic gasoline-related air pollution, while improving fuel performance at the same time, is the application of nanoparticles. Considering the above, the present paper aims to review and critically discuss the improvements made in engine performance and exhaust emission parameters by adding nanosized fuel additives in gasoline. Overall, the addition of fuel nanoadditives enhances the thermo-physical properties of the fuel and improves combustion characteristics. Moreover, the inclusion of the fuel nanoadditives generally results in early combustion and shortened ignition delay. In more detail, the optimum quantity of fuel nanoadditives is associated with improvements in ignition characteristics and reductions in exhaust emissions. The present work also scrutinizes the adverse health effects of various gasoline-related emissions. Finally, possible mechanisms underlying the improvements in gasoline properties and its combustion in the presence of nanoadditives are also reviewed and discussed.

Anaerobic digestion (AD) of organic wastes is among the most promising approaches used for the simultaneous treatment of various waste streams, environment conservation, and renewable bioenergy generation (biomethane). Among the latest innovations investigated to enhance the overall performance of this process both qualitatively and quantitatively, the application of some nanoparticles (NPs) has attracted a great deal of attention. Typically, the NPs of potential benefit to the AD process could be divided into three groups: (i) zero-valent iron (ZVI) NPs, (ii) metallic and metal oxides NPs, and (iii) carbon-based NPs. The present review focuses on the latest findings reported on the application of these NPs in AD process and presents their various mechanisms of action leading to higher or lower biogas production rates. Among the NPs studies, ZVI NPs could be regarded as the most promising nanomaterials for enhancing biogas production through stabilizing the AD process as well as by stimulating the growth of beneficial microorganisms to the AD process and the enzymes involved. Future research should focus on various attributes of NPs when used as additives in biogas production, including facilitating mixing and pumping operations, enriching the population and diversity of beneficial microorganisms for AD, improving biogas release, and inducing the production and activity of AD-related enzymes. The higher volume of methane-enriched biogas would be translated into higher returns on investment and could therefore, result in further growth of the biogas production industry. Nevertheless, efforts should be devoted to decreasing the price of NPs so that the enhanced biogas and methane production (by over 90%, compared to control) would be more economically justified, facilitating the large-scale application of these compounds. In addition to economic considerations, environmental issues are also regarded as major constraints which should be addressed prior to widespread implementation of NP-augmented AD processes. More specifically, the fate of NPs augmented in AD process should be scrutinized to ensure maximal beneficial impacts while adverse environmental/health consequences are minimized.

There are 17 human-biting ticks known in Australia. The bites of Ixodes holocyclus, Ornithodoros capensis, and Ornithodoros gurneyi can cause paralysis, inflammation, and severe local and systemic reactions in humans, respectively. Six ticks, including Amblyomma triguttatum, Bothriocroton hydrosauri, Haemaphysalis novaeguineae, Ixodes cornuatus, Ixodes holocyclus, and Ixodes tasmani may transmit Coxiella burnetii, Rickettsia australis, Rickettsia honei, or Rickettsia honei subsp. marmionii. These bacterial pathogens cause Q fever, Queensland tick typhus (QTT), Flinders Island spotted fever (FISF), and Australian spotted fever (ASF). It is also believed that babesiosis can be transmitted by ticks to humans in Australia. In addition, Argas robertsi, Haemaphysalis bancrofti, Haemaphysalis longicornis, Ixodes hirsti, Rhipicephalus australis, and Rhipicephalus sanguineus ticks may play active roles in transmission of other pathogens that already exist or could potentially be introduced into Australia. These pathogens include Anaplasma spp., Bartonella spp., Burkholderia spp., Francisella spp., Dera Ghazi Khan virus (DGKV), tick-borne encephalitis virus (TBEV), Lake Clarendon virus (LCV), Saumarez Reef virus (SREV), Upolu virus (UPOV), or Vinegar Hill virus (VINHV). It is important to regularly update clinicians' knowledge about tick-borne infections because these bacteria and arboviruses are pathogens of humans that may cause fatal illness. An increase in the incidence of tick-borne infections of human may be observed in the future due to changes in demography, climate change, and increase in travel and shipments and even migratory patterns of birds or other animals. Moreover, the geographical conditions of Australia are favorable for many exotic ticks, which may become endemic to Australia given an opportunity. There are some human pathogens, such as Rickettsia conorii and Rickettsia rickettsii that are not currently present in Australia, but can be transmitted by some human-biting ticks found in Australia, such as Rhipicephalus sanguineus, if they enter and establish in this country. Despite these threats, our knowledge of Australian ticks and tick-borne diseases is in its infancy.

The emergence and prevalence of multi-drug-resistant bacterial strains increase the potential for outbreaks of incurable infections. The discovery of novel antibiotics and pharmacological preparations requires the identification of novel bioactive small molecules. A specific, sensitive, and reliable quantification method using high-performance liquid chromatography (HPLC) with UV detection was developed for the determination of total persipeptides (A and B), which are cyclic pentapeptides found in the fermentation broth of Streptomyces zagrosensis UTMC 1154 that exhibit bioactivity against methicillin-resistant Staphylococcus aureus (MRSA). A simple liquid–liquid extraction (LLE) method using butanol was employed to extract persipeptides from the fermentation broth prior to HPLC analysis. The chromatographic separation of persipeptides and the internal standard, virginiamycin, was achieved with a gradient of acetonitrile and water on a C18 reversed-phase analytical column in a 25-min analytical run utilizing a flow rate of 0.8 mL min−1 and detection at 210 nm. The whole assay was validated, and the method presented a linear response range with a regression coefficient of determination R 2 of 0.9996 for the quantification of persipeptides in the concentration range of 3.9–250.0 µg mL−1, as well as extraction recoveries ranging from 54.78 ± 9.83 % to 56.45 ± 16.33 %. The bias and the precision of the proposed method were

A sustainable management of environment and agriculture is crucial to protect soil, water, and air during intensified agriculture practices as well as huge industrial and transportation activities. A promising tool to address these challenges could be the application of biochar, a carbonaceous product of biomass pyrolysis. The efficiency of biochar could be improved through physical, chemical and microbial procedures. Engineered biochar could then be applied for various applications ranging from sustainable agriculture to pollution remediation and catalytic reactions. Biochar engineering allows achieving biochar properties which are optimum for specific applications and/or under specific conditions. This would lead to harnessing the favorable features of biochar and to enhance its efficiency while simultaneously minimizing the existing tradeoffs. This review covers the production and applications of engineered biochar by summarizing great deals of research and knowledge on the field. Unlike previous reviews, herein biochar physical and chemical properties and the factors affecting them (i.e., biomass nature and pyrolysis conditions) have been discussed in detail. Moreover, the contributions of each physical and chemical activation/modification method to improving biochar characteristics with respect to environmental applications have been specifically scrutinized. By providing the state-of-the-art knowledge about engineered biochar production, properties, and applications, this review aims to help research in this field for identification of the culprits that must be addressed in future experiments.

More than other bacteria Actinobacteria, especially the mycelium forming ones impress by their appearance, the color of the aerial mycelium, of the substrate mycelium and also of pigments that diffuse into the agar (Cross 1989; Krasil’nikov 1979; Kuster 1976) and the morphology of their differentiation stages (Gottlieb 1961) which will be described in the later chapters. The aerial mycelium which makes them look like a fungus and the often three dimensional shape of the colony. The color of the aerial mycelium has been used by many groups for a first classification (Flaig and Kutzner 1960; Ettlinger et al. 1958; Shirling and Gottlieb 1966; Tresner and Backus 1963). The main classification groups are: white, grey white, cream (Streptomyces albus); yellow-grey (Streptomyces griseus); rose, pale violet (Streptomyces fradiae, Microbispora rosea), rose-grey (Streptomyces lavendulae); pale brown, red brown (Streptomyces fragilis); pale blue, grey-blue (Streptomyces viridochromogenes); blue green (Streptomyces glaucescens, Actinomadura rubrobrunnea); pale green, green (Streptomyces prasinus, Microtetraspora viridis); pale grey, grey (Streptomyces violaceoruber, Microtetraspora glauca) (Blinov and Khokhlov 1970). By the description of the aerial mycelium color three points have to be kept in mind. The first is that the typical color is only expressed if the culture is also sporulating. Different species often sporulate on different media, so a number of agar cultures have to be prepared to get good results. The second is the diffusion of pigments from the substrate mycelium into the aerial mycelium which can have influences on the shade of the aerial mycelium. The third is the experience with many different Actinobacteria and their pigmentation, to do this grouping well. It is therefore very important to use the same media and culture conditions for all strains that will be compared. Over the years the use of the media from Shirling and Gottlieb (1966) from the “International Streptomyces Project/ISP” has been established in nearly all labs working with Actinobacteria (composition of media, see Sect. 11.2.1).

Although currently microalgae biomass is not considered as a sustainable feedstock for biofuel production, future developments of microalgae cultivation and harvest could make the commercial application of such fast-growing photosynthetic biomass economically and environmentally feasible. This article aims at reviewing thermochemical conversion of microalgae into bio-crude oil through pyrolysis and hydrothermal liquefaction technologies. Subsequently, possible solutions to overcome the constraints to achieve the sustainable conversion of microalgae biomass are discussed in detail. The drawbacks of bio-crude oil as a transportation fuel and the technologies required for its upgrading are highlighted. Currently, microalgae-derived bio-crude oil is inferior to biodiesel and diesel in terms of quality, thus cannot be used as a transportation or jet fuel. It requires catalytic upgrading steps and further processing, including durable and cost-effective catalysts with strong regenerative capabilities.

The kynurenine pathway is important in cellular energy generation and limiting cellular ageing as it degrades about 90% of dietary tryptophan into the essential co-factor NAD+ (nicotinamide adenine dinucleotide). Prior to the production of NAD+, various intermediate compounds with neuroactivity (kynurenic acid, quinolinic acid) or antioxidant activity (3-hydroxykynurenine, picolinic acid) are synthesized. The kynurenine metabolites can participate in numerous neurodegenerative disorders (Alzheimer disease, amyotrophic lateral sclerosis, Huntington disease, and Parkinson disease) or other diseases such as AIDS, cancer, cardiovascular diseases, inflammation, and irritable bowel syndrome. Recently, the role of gut in affecting the emotional and cognitive centres of the brain has attracted a great deal of attention. In this review, we focus on the bidirectional communication between the gut and the brain, known as the gut-brain axis. The interaction of components of this axis, namely, the gut, its microbiota, and gut pathogens; tryptophan; the kynurenine pathway on tryptophan availability; the regulation of kynurenine metabolite concentration; and diversity and population of gut microbiota, has been considered.

Microbial-derived products, while do not have many environmental side effects of their synthetic counterparts, have proved more efficient than those synthetically obtained. The nature has provided a treasure of microorganisms with capabilities to produce vast variety of novel compounds. This ability has been arised during long last of evolution and adaptation to diverse chemical and physical microenviroments. Microbial-derived metabolites have made their own space in industries and therefore human life. Among these microorganisms, halophilic and halotolerant actinobacteria are recently gaining much attentions. Metabolites and biological functions from halophilic or halotolerant members of this phylum of bacteria may resolving the ever-increasing thirst of industry for metabolites with salt-tolerancy to cope a range of issues from environmental pollution to diseases and world’s hunger. In the current chapter, it has been tried to introduce the less dealt group of halophilic and halotolerant actinobacteria, and shed light on their potential to be exploited in various industry sectors.