Carbon dioxide capture, sequestration, and utilization models for carbon management and transformation

The elevated level of carbon dioxide in the atmosphere has become a pressing concern for environmental health due to its contribution to climate change and global warming. Simultaneously, the energy crisis is a significant issue for both developed and developing nations. In response to these challenges, carbon capture, sequestration, and utilization (CCSU) have emerged as promising solutions within the carbon-neutral bioenergy sector. Numerous technologies are available for CCSU including physical, chemical, and biological routes. The aim of this study is to explore the potential of CCSU technologies, specifically focusing on the use of microorganisms based on their well-established metabolic part. By investigating these biological pathways, we aim to develop sustainable strategies for climate management and biofuel production. One of the key novelties of this study lies in the utilization of microorganisms for CO2 fixation and conversion, offering a renewable and efficient method for addressing carbon emissions. Algae, with its high growth rate and lipid contents, exhibits CO2 fixation capabilities during photosynthesis. Similarly, methanogens have shown efficiency in converting CO2 to methane by methanogenesis, offering a viable pathway for carbon sequestration and energy production. In conclusion, our study highlights the importance of exploring biological pathways, which significantly reduce carbon emissions and move towards a more environmentally friendly future. The output of this review highlights the significant potential of CCSU models for future sustainability. Furthermore, this review has been intensified in the current agenda for reduction of CO2 at considerable extends with biofuel upgrading by the microbial-shift reaction.

The Impact of Fermentation on the Antioxidant Activity of Food Products

From ancient times to the present day, fermentation has been utilized not only for food preservation but also for enhancing the nutritional and functional properties of foods. This process is influenced by numerous factors, including the type of microorganisms used, substrate composition, pH, time, and temperature, all of which can significantly alter the characteristics of the final product. Depending on the parameters, fermentation enhances the bioactive content of the products and imparts the necessary properties, such as antioxidant characteristics, for the products to be considered functional. The enhancement of these properties, particularly antioxidant activity, enriches foods with bioactive compounds and functional attributes, contributing to improved health benefits. Through a review of recent research, this study elucidates how different fermentation processes can enhance the bioavailability and efficacy of antioxidants, thereby improving the nutritional and functional qualities of foods. This study investigated the multifaceted effects of fermentation on antioxidant properties by exploring various types and conditions of fermentation. It highlights specific examples from dairy products and other food categories as well as the valorization of food waste and byproducts. The findings underscore the potential of fermentation as a sustainable method to produce health-promoting foods with elevated antioxidant activities, offering new perspectives for food science and technology.

Use of heterogeneous catalysis in sustainable biofuel production

Biofuel is a sustainable energy source that may use to replace fossil-based carbon dioxide and mitigate the adverse effects of exhaust emissions. Nowadays, we need to replace petroleum fuels with alternatives from environmentally sustainable sources of increasing importance. Biofuels derived from biomass have gained considerable attention, and thus most of the traditional methods that harm the environment and humans have retreated. Developing an active and stable heterogeneous catalyst is a step of utmost importance in the renewable liquid fuel technology. Thus, there is a great interest in developing methods for producing liquid fuels from non-edible sources. It may also be from dry plant tissues such as agricultural waste. Lignocellulosic biomass can be a sustainable source for producing renewable fuels and chemicals, as well as the replacement of petroleum products. Hence, the researchers aspired to synthesize new catalysts using a cheap technology developed to hydrolyze cellulose and then produce bioethanol without needing expensive enzymes, which may ultimately lead to a lower fuel price. In this paper, we will focus on the recent technologies used to produce sustainable biofuels through inexpensive incentives and innocuous to the environment.

Muscle cell proliferation using water-soluble extract from nitrogen-fixing cyanobacteria Anabaena sp. PCC 7120 for sustainable cultured meat production

Muscle cell cultivation, specifically the culture of artificial meat from livestock-derived cells in serum-free media is an emerging technology and has attracted much attention. However, till now, the high cost of production and environmental load have been significant deterrents. This study aims to provide an alternate growth-promoting substance that is free from animal derivatives and lowers nitrogen pollution. We have extracted water-soluble compounds from the filamentous nitrogen-fixing cyanobacteria Anabaena sp. PCC 7120 by the ultrasonication method. The heat-inactivated and molecular weight separation experiments were conducted to identify the bioactive compound present in the extract. Finally, the compounds soluble in water (CW) containing the water-soluble pigment protein, phycocyanin as a bioactive compound, was added as a growth supplement to cultivate muscle cells such as C2C12 muscle cells and quail muscle clone 7 (QM7) cells to analyze the effectiveness of the extract. The results indicated that CW had a positive role in muscle cell proliferation. A three-dimensional (3-D) cell-dense structure was fabricated by culturing QM7 cells using the extract. Furthermore, the nitrogen-fixing cyanobacterial extract has vast potential for cultured meat production without animal sera in the near future.

Novel Corrugated Long Period Grating Surface Balloon-Shaped Heterocore-Structured Plastic Optical Fibre Sensor for Microalgal Bioethanol Production

A novel long period grating (LPG) inscribed balloon-shaped heterocore-structured plastic optical fibre (POF) sensor is described and experimentally demonstrated for real-time measurement of the ultra-low concentrations of ethanol in microalgal bioethanol production applications. The heterocore structure is established by coupling a 250 μm core diameter POF between two 1000 μm diameter POFs, thus representing a large core-small core-large core configuration. Before coupling as a heterocore structure, the sensing region or small core fibre (SCF; i.e., 250 μm POF) is modified by polishing, LPG inscription, and macro bending into a balloon shape to enhance the sensitivity of the sensor. The sensor was characterized for ethanol-water solutions in the ethanol concentration ranges of 20 to 80 %v/v, 1 to 10 %v/v, 0.1 to 1 %v/v, and 0.00633 to 0.0633 %v/v demonstrating a maximum sensitivity of 3 × 10⁶ %/RIU, a resolution of 7.9 × 10^-6 RIU, and a limit of detection (LOD) of 9.7 × 10^-6 RIU. The experimental results are included for the intended application of bioethanol production using microalgae. The characterization was performed in the ultra-low-level ethanol concentration range, i.e., 0.00633 to 0.03165 %v/v, that is present in real culturing and production conditions, e.g., ethanol-producing blue-green microalgae mixtures. The sensor demonstrated a maximum sensitivity of 210,632.8 %T/%v/v (or 5 × 10⁶ %/RIU as referenced from the RI values of ethanol-water solutions), resolution of 2 × 10^-4%v/v (or 9.4 × 10^-6 RIU), and LOD of 4.9 × 10^-4%v/v (or 2.3 × 10^-5 RIU). Additionally, the response and recovery times of the sensor were investigated in the case of measurement in the air and the ethanol-microalgae mixtures. The experimentally verified, extremely high sensitivity and resolution and very low LOD corresponding to the initial rate of bioethanol production using microalgae of this sensor design, combined with ease of fabrication, low cost, and wide measurement range, makes it a promising candidate to be incorporated into the bioethanol production industry as a real-time sensing solution as well as in other ethanol sensing and/or RI sensing applications.

Cyanobacteria-Mediated Immune Responses in Pepper Plants against Fusarium Wilt

Research in plant pathology has increasingly focused on developing environmentally friendly, effective strategies for controlling plant diseases. Cyanobacteria, including Desmonostoc muscorum, Anabaena oryzae, and Arthrospiraplatensis, were applied to Capsicum annuum L. to induce immunity against Fusarium wilt. Soil irrigation and foliar shoots (FS) application were used in this investigation. The disease symptoms, disease index, osmotic contents, total phenol, Malondialdehyde (MDA), hydrogen peroxide (H₂O₂), antioxidant enzymes (activity and isozymes), endogenous hormone content, and response to stimulation of defense resistance in infected plants were assessed. Results demonstrated that using all cyanobacterial aqueous extracts significantly reduced the risk of infection with Fusarium oxysporum. One of the most effective ways to combat the disease was through foliar spraying with Arthrospira platensis, Desmonostoc muscorum, and Anabaena oryzae (which provided 95, 90, and 69% protection percent, respectively). All metabolic resistance indices increased significantly following the application of the cyanobacterial aqueous extracts. Growth, metabolic characteristics, and phenols increased due to the application of cyanobacteria. Polyphenol oxidase (PPO) and peroxidase (POD) expressions improved in response to cyanobacteria application. Furthermore, treatment by cyanobacteria enhanced salicylic acid (SA) and Indole-3-Acetic Acid (IAA) in the infected plants while decreasing Abscisic acid (ABA). The infected pepper plant recovered from Fusarium wilt because cyanobacterial extract contained many biologically active compounds. The application of cyanobacteria through foliar spraying seems to be an effective approach to relieve the toxic influences of F. oxysporum on infected pepper plants as green and alternative therapeutic nutrients of chemical fungicides.

Production of Bioethanol—A Review of Factors Affecting Ethanol Yield

Fossil fuels are a major contributor to climate change, and as the demand for energy production increases, alternative sources (e.g., renewables) are becoming more attractive. Biofuels such as bioethanol reduce reliance on fossil fuels and can be compatible with the existing fleet of internal combustion engines. Incorporation of biofuels can reduce internal combustion engine (ICE) fleet carbon dioxide emissions. Bioethanol is typically produced via microbial fermentation of fermentable sugars, such as glucose, to ethanol. Traditional feedstocks (e.g., first-generation feedstock) include cereal grains, sugar cane, and sugar beets. However, due to concerns regarding food sustainability, lignocellulosic (second-generation) and algal biomass (third-generation) feedstocks have been investigated. Ethanol yield from fermentation is dependent on a multitude of factors. This review compares bioethanol production from a range of feedstocks, and elaborates on available technologies, including fermentation practices. The importance of maintaining nutrient homeostasis of yeast is also examined. The purpose of this review is to provide industrial producers and policy makers insight into available technologies, yields of bioethanol achieved by current manufacturing practices, and goals for future innovation.

Seaweeds as a Fermentation Substrate: A Challenge for the Food Processing Industry

Seaweeds are gaining momentum as novel and functional food and feed products. From whole consumption to small bioactive compounds, seaweeds have remarkable flexibility in their applicability, ranging from food production to fertilizers or usages in chemical industries. Regarding food production, there is an increasing interest in the development of novel foods that, at the same time, present high nutritious content and are sustainably developed. Seaweeds, because they require no arable land, no usage of fresh water, and they have high nutritious and bioactive content, can be further explored for the development of newer and functional food products. Fermentation, especially performed by lactic acid bacteria, is a method used to produce functional foods. However, fermentation of seaweed biomass remains an underdeveloped topic that nevertheless demonstrates high potential for the production of new alimentary products that hold and further improve the organoleptic and beneficial properties that these organisms are characterized for. Although further research has to be deployed in this field, the prebiotic and probiotic potential demonstrated by fermented seaweed can boost the development of new functional foods.

Microalgal culture in animal cell waste medium for sustainable 'cultured food' production

'Cultured food' has tremendous potential as a sustainable meat alternative. Increased cultured food production is increasing the amount of waste medium from cell culture. Nitrogen- and phosphorus-containing compounds in waste medium can cause eutrophication of water bodies. Currently, microalgae are used in energy production, environmental protection, agriculture and pharmaceutical and health food industries. Here, we used the microalgae, Chlorococcum littorale and Chlorella vulgaris and the waste medium of C2C12 cells for a case study. We found that 80% and 26% of ammonia and 16% and 15% of phosphorus in the waste medium were consumed by C. littorale and C. vulgaris, respectively. In addition, C. littorale and C. vulgaris proliferated 3.2 folds and 1.6 folds, respectively, after seven days in the waste medium that was enhanced by adjusting medium salt concentration. This report demonstrates the potential of sustainability for solving the issue of waste medium production during the production of cultured food.

Molecular identification, biomass, and biochemical composition of the marine chlorophyte Chlorella sp. MF1 isolated from Suez Bay

BACKGROUND

An Egyptian indigenous unicellular green microalga was isolated from the coastal water of Suez Bay (N 29.92°, E 32.473°), Red Sea, Egypt. The molecular analysis based on 18S rRNA sequence showed that the gene sequence for this strain was highly similar (100% identity and 98% query cover) to different Chlorella strains isolated from different habitats.

RESULTS

The observed morphological characters together with the molecular phylogeny assigned the isolated microalga as Chlorella sp. MF1 with accession number KX228798. This isolated strain was cultivated for estimation of its growth and biochemical composition. The mean specific growth rate (μ) was 0.273 day-1. Both the biomass productivity and the cellular lipid content increased by increasing salinity of the growth medium, recording a maximum of 6.53 gDW l-1 and 20.17%, respectively, at salinity 40.4. Fourteen fatty acids were identified. The total saturated fatty acid percentage was 54.73% with stearic (C18:0), arachidic (C20:0), and palmitic acids (C16:0) as major components, while the total unsaturated fatty acid percentage was 45.27% with linoleic acid (C18:2c) and oleic acid (C18:1) as majors.

CONCLUSION

This algal strain proved to be a potential newly introduced microalga as one of the most proper options available for microalgae-based biodiesel production. The proximate analysis showed the protein content at 39.85% and carbohydrate at 23.7%, indicating its accessibility to various purposes.

Algae as potential feedstock for the production of biofuels and value-added products: Opportunities and challenges

The current review explores the potential application of algal biomass for the production of biofuels and bio-based products. The variety of processes and pathways through which bio-valorization of algal biomass can be performed are described in this review. Various lipid extraction techniques from algal biomass along with transesterification reactions for biodiesel production are briefly discussed. Processes such as the pretreatment and saccharification of algal biomass, fermentation, gasification, pyrolysis, hydrothermal liquefaction, and anaerobic digestion for the production of biohydrogen, bio-oils, biomethane, biochar (BC), and various bio-based products are reviewed in detail. The biorefinery model and its collaborative approach with various processes are highlighted for the production of eco-friendly, sustainable, and cost-effective biofuels and value-added products. The authors also discuss opportunities and challenges related to bio-valorization of algal biomass and use their own perspective regarding the processes involved in production and the feasibility to make algal research a reality for the production of biofuels and bio-based products in a sustainable manner.

Advanced Technologies for the Extraction of Marine Brown Algal Polysaccharides

Over the years, brown algae bioactive polysaccharides laminarin, alginate and fucoidan have been isolated and used in functional foods, cosmeceutical and pharmaceutical industries. The extraction process of these polysaccharides includes several complex and time-consuming steps and the correct adjustment of extraction parameters (e.g., time, temperature, power, pressure, solvent and sample to solvent ratio) greatly influences the yield, physical, chemical and biochemical properties as well as their biological activities. This review includes the most recent conventional procedures for brown algae polysaccharides extraction along with advanced extraction techniques (microwave-assisted extraction, ultrasound assisted extraction, pressurized liquid extraction and enzymes assisted extraction) which can effectively improve extraction process. The influence of these extraction techniques and their individual parameters on yield, chemical structure and biological activities from the most current literature is discussed, along with their potential for commercial applications as bioactive compounds and drug delivery systems.

Algae biorefinery: Review on a broad spectrum of downstream processes and products

Algae biomass comprises variety of biochemicals components such as carbohydrates, lipids and protein, which make them a feasible feedstock for biofuel production. However, high production cost mainly due to algae cultivation remains the main challenge in commercializing algae biofuels. Hence, extraction of other high value-added bioproducts from algae biomass is necessary to enhance the economic feasibility of algae biofuel production. This paper is aims to deliberate the recent developments of conventional technologies for algae biofuels production, such as biochemical and chemical conversion pathways, and extraction of a variety of bioproducts from algae biomass for various potential applications. Besides, life cycle evaluation studies on microalgae biorefinery are presented, focusing on case studies for various cultivation techniques, culture medium, harvesting, and dewatering techniques along with biofuel and bioenergy production pathways. Overall, the algae biorefinery provides new opportunities for valorisation of algae biomass for multiple products synthesis.

Enhancement of bioethanol production from Gracilaria verrucosa by Saccharomyces cerevisiae through the overexpression of SNR84 and PGM2

A total monosaccharide concentration of 47.0 g/L from 12% (w/v) Gracilaria verrucosa was obtained by hyper thermal acid hydrolysis with 0.2 M HCl at 140°C for 15 min and enzymatic saccharification with CTec2. To improve galactose utilization, we overexpressed two genes, SNR84 and PGM2, in a Saccharomyces cerevisiae CEN-PK2 using CRISPR/Cas-9. The overexpression of both SNR84 and PGM2 improved galactose utilization and ethanol production compared to the overexpression of each gene alone. The overexpression of both SNR84 and PGM2 and of PGM2 and SNR84 singly in S. cerevisiae CEN-PK2 Cas9 produced 20.0, 18.5, and 16.5 g/L ethanol with ethanol yield (Y_EtOH) values of 0.43, 0.39, and 0.35, respectively. However, S. cerevisiae CEN-PK2 adapted to high concentration of galactose consumed galactose completely and produced 22.0 g/L ethanol at a Y_EtOH value of 0.47. The overexpression of both SNR84 and PGM2 increased the transcriptional levels of GAL and regulatory genes; however, the transcriptional levels of these genes were lower than those in S. cerevisiae adapted to high galactose concentrations.

Biochemical characteristics of cellulose and a green alga degradation by Gilvimarinus japonicas 12-2T, and its application potential for seaweed saccharification

Cellulose is one of the major constituents of seaweeds, but reports of mechanisms in microbial seaweed degradation in marine environment are limited, in contrast to the multitude of reports for lignocellulose degradation in terrestrial environment. We studied the biochemical characteristics for marine cellulolytic bacterium Gilvimarinus japonicas 12-2^T in seaweed degradation. The bacterial strain was found to degrade green and red algae, but not brown algae. It was shown that the bacterial strain employs various polysaccharide hydrolases (endocellulase, agarase, carrageenanase, xylanase, and laminarinase) to degrade seaweed polysaccharides. Electrophoretic analysis and peptide sequencing showed that the major protein bands on the electrophoresis gel were homologous to known glucanases and glycoside hydrolases. A seaweed hydrolysate harvested from the bacterial culture was found useful as a substrate for yeasts to produce ethanol. These findings will provide insights into possible seaweed decomposition mechanisms of Gilvimarinus, and its biotechnological potential for ethanol production from inedible seaweeds.

Nanobiopolymers Fabrication and Their Life Cycle Assessments

Living organisms produced nanopolymers (nanobiopolymers for short), such as nanocellulose, nanochitin, nanosilk, nanostarch, and microbial nanobiopolymers, having received widely scientific and engineering interests in recent years. Compare with petroleum-based polymers, biopolymers are sustainable and biodegradable. The unique structural features that stem from nanosized effects, such as ultrahigh aspect ratio and length-diameter ratio, further endow nanobiopolymers with high transparence and versatile processability. To fabricate these nanobiopolymers, a variety of mechanical, chemical, and synthetic biology techniques have been developed. The applications of the isolated nanobiopolymers have been extended from polymer fillers into wide emerging high-tech fields, such as biomedical devices, bioplastics, display panels, ultrafiltration membranes, energy storage devices, and catalytic supports. Accordingly, in the review, the authors first introduce isolation techniques to fabricate nanocellulose, nanochitin, nanosilk, and nanostarch. Then, the authors summarized the nanobiopolymers produced from biosynthetic pathway, including microbial polyamides, polysaccharides, and polyesters. On the other hand, most of these techniques require high energy consumption and usage of chemical reagents. In this regard, life cycle assessment offered a quantitative route to precisely evaluate and compare environmental benefits of different artificial isolation approaches, which are also summarized in the second section of the review.

Comparison of transplastomic Chlamydomonas reinhardtii and Nicotiana tabacum expression system for the production of a bacterial endoglucanase

The bulk production of recombinant enzymes by either prokaryotic or eukaryotic organisms might contribute to replace environmentally non-friendly chemistry-based industrial processes with enzyme-based biocatalysis, provided the cost of enzyme production is low. In this context, it is worth noting that the production of recombinant proteins by photosynthetic organisms offer both eukaryotic (nuclear) and prokaryotic (chloroplast) alternatives, along with the advantage of an autotrophic nutrition. Compared to nuclear transformation, chloroplast transformation generally allows a higher level of accumulation of the recombinant protein of interest. Furthermore, among the photosynthetic organisms, there is a choice of using either multicellular or unicellular ones. Tobacco, being a non-food and non-feed plant, has been considered as a good choice for producing enzymes with applications in technical industry, using a transplastomic approach. Also, unicellular green algae, in particular Chlamydomonas reinhardtii, have been proposed as candidate organisms for the production of recombinant proteins. In the light of the different features of these two transplastomic systems, we decided to make a direct comparison of the efficiency of production of a bacterial endoglucanase. With respect to the amount obtained, 14 mg g-1 of biomass fresh weight equivalent to 8-10% of the total protein content and estimated production cost, 1.5-2€ kg-1, tobacco proved to be far more favorable for bulk enzyme production when compared to C. reinhardtii which accumulated this endoglucanase at 0.003% of the total protein.

Identification and Characterization of a 25 kDa Protein That Is Indispensable for the Efficient Saccharification of Eisenia bicyclis in the Digestive Fluid of Aplysia kurodai

The digestive fluid of the sea hare Aplysia kurodai can liberate approximately 2.5 mg of glucose from 10 mg of dried Eisenia bicyclis powder. Although laminaran, a major storage polysaccharide in E. bicyclis, is easily digested to glucose by the synergistic action of the 110 and 210 kDa A. kurodai β-glucosidases (BGLs), glucose is not liberated from E. bicyclis by direct incubation with these BGLs. To clarify this discrepancy, we searched for an Eisenia hydrolysis enhancing protein (EHEP) in the digestive fluid of A. kurodai. A novel 25 kDa protein that enhances E. bicyclis saccharification by β-glucosidases was purified to a homogeneous state from the digestive fluid of A. kurodai, and its cDNA was cloned from total cDNAs reverse-transcribed from hepatopancreas total RNA. The E. bicyclis extract strongly inhibited BGLs, suggesting some compound within this brown alga functioned as a feeding deterrent. However, when E. bicyclis was incubated with BGLs in the presence of EHEP, glucose production was markedly increased. As E. bicyclis is rich in phlorotannin, which are only found in brown algae, our study suggested that these compounds are the main BGL inhibitors in E. bicyclis extract. EHEP protects BGLs from phlorotannin inhibition by binding to phlorotannins and forming an insoluble complex with phloroglucinol and phlorotannins. These findings indicated that EHEP plays a key role in the saccharification of brown seaweeds containing phlorotannins in the digestive fluid of A. kurodai. This is the first report of EHEP as a phlorotannin-binding protein that protects BGLs from inhibition.

Citeromyces matritensis M37 is a salt-tolerant yeast that produces ethanol from salted algae

Algae are referred to as a third-generation biomass for ethanol production. However, salinity treatment is a problem that needs to be solved, because algal hydrolysates often contain high salt. Here, we isolated the salt-tolerant ethanol-producing yeast Citeromyces matritensis M37 from the east coast of Miura Peninsula in Japan. This yeast grew under osmotic stress conditions (20% NaCl or 60% glucose). It produced 6.55 g/L ethanol from YPD medium containing 15% NaCl after 48 h, and the ethanol accumulation was observed even at 20% NaCl. Using salted Undaria pinnatifida (wakame), we obtained 6.33 g/L glucose from approx. 150 g/L of the salted wakame powder with acidic and heat pretreatment followed by enzymatic saccharification, and the ethanol production reached 2.58 g/L for C. matritensis M37. The ethanol concentration was 1.4 times higher compared with that using the salt-tolerant ethanol-producing yeast Zygosaccharomyces rouxii S11.

Improving carbohydrate production of Chlorella sorokiniana NIES-2168 through semi-continuous process coupled with mixotrophic cultivation

Biofuels from microalgae is now a hot issue of great potential. However, achieving high starch productivity with photoautotrophic microalgae is still challenging. A feasible approach to enhance the growth and target product of microalgae is to conduct mixotrophic cultivation. The appropriate acetate addition combined with CO2 supply as dual carbon sources (i.e., mixotrophic cultivation) could enhance the cell growth of some microalgae species, but the effect of acetate-mediated mixotrophic culture mode on carbohydrate accumulation in microalgae remains unclear. Moreover, there is still lack of the information concerning how to increase the productivity of carbohydrates from microalgae under acetate-amended mixotrophic cultivation and how to optimize the engineering strategies to achieve the goal. This study was undertaken to develop an optimal acetate-contained mixotrophic cultivation system coupled with effective operation strategies to markedly improve the carbohydrate productivity of Chlorella sorokiniana NIES-2168. The optimal carbohydrate productivity of 695 mg/L/d was obtained, which is the highest value ever reported. The monosaccharide in the accumulated carbohydrates is mainly glucose (i.e., 85-90%), which is very suitable for bio-alcohols fermentation. Hence, by applying the optimal process developed in this study, C. sorokiniana NIES-2168 has a high potential to serve as a feedstock for subsequent biofuels conversion.

Comparative evaluation of chemical and enzymatic saccharification of mixotrophically grown de-oiled microalgal biomass for reducing sugar production

For the commercialization of microalgal based biofuels, utilization of de-oiled carbohydrate rich biomass is important. In the present study, chemo-enzymatic hydrolysis of mixotrophically grown Scenedesmus sp. CCNM 1077 de-oiled biomass is evaluated. Among the chemical hydrolysis, use of 0.5M HCl for 45 min at 121°C resulted in highest saccharification yield of 37.87% w/w of de-oiled biomass. However, enzymatic hydrolysis using Viscozyme L at loading rate of 20 FBGU/g of de-oiled biomass, pH 5.5 and temperature 45°C for 72 h resulted in saccharification yield of 43.44% w/w of de-oiled biomass. Further, 78% ethanol production efficiency was achieved with enzymatically hydrolyzed de-oiled biomass using yeast Saccharomyces cerevisiae ATCC 6793. These findings of the present study show application of mixotrophically grown de-oiled biomass of Scenedesmus sp. CCNM 1077 as promising feedstock for bioethanol production.

Draft genome of agar-degrading marine bacterium Gilvimarinus agarilyticus JEA5

Gilvimarinus agarilyticus JEA5, which effectively degrades agar, was isolated from the seawater of Jeju Island, Republic of Korea. Here, we report the draft genome sequence of G. agarilyticus JEA5 with a total genome size of 4,179,438bp from 2 scaffolds (21 contigs) with 53.15% G+C content. Various polysaccharidases including 11 predicted agarases were observed from the draft genome of G. agarilyticus JEA5.

Editorial: Latest methods and advances in biotechnology

The latest "Biotech Methods and Advances" special issue of Biotechnology Journal continues the BTJ tradition of featuring the latest breakthroughs in biotechnology. The special issue is edited by our Editors-in-Chief, Prof. Sang Yup Lee and Prof. Alois Jungbauer and covers a wide array of topics in biotechnology, including the perennial favorite workhorses of the biotech industry, Chinese hamster ovary (CHO) cell and Escherichia coli.