Biomass Generation Research Articles

A plant-wide modelling framework to describe microalgae growth on liquid digestate in agro-zootechnical biomethane plants

Microalgae cultivation on liquid digestate from the anaerobic co-digestion of agricultural feedstocks is an interesting option for digestate nutrient removal and resource recovery coupled to biomass generation. Both the reactors considered in such a biorefinery system involve complex bioprocesses. Although different pilot-scale systems coupling anaerobic digestion and algae-based bioremediation processes have been described, no previous attempts to model the entire system are available to date. In this work, a plant-wide model, named ADAB (anaerobic digestion algae-bacteria), is presented, coupling two well-established models for anaerobic digestion (IWA – ADM1) and algae-based bioremediation processes (ALBA). The models were modified with necessary equations and extensions to develop a dedicated model interface. Phosphorous dynamics were integrated, including activity corrections and precipitation processes. The ALBA model was also integrated with thermal modelling to simulate outdoor raceway ponds and greenhouse-covered systems. Solid/liquid separation units for digestate pre-treatment were also included. The prediction consistency of the adopted physicochemical sub-model (PCM) was verified with results from both reference literature and Visual MINTEQ. The reduced complexity of the PCM limits the model field of application, but it results in better computational performance and seems to be particularly suitable to simulate agro-zootechnical digesters. A scenario analysis including different co-digester design and operating conditions was carried out to assess the impacts on microalgae cultivation. It highlighted the importance of a proper biorefinery design and yet a noteworthy robustness of the system performance. The use of the ADAB model can facilitate a more realistic assessment of the technical, environmental, and economic feasibility of full-scale microalgal biorefineries based on digestate.

Unlocking Nature’s Toolbox: glutamate-inducible recombinant protein production from the Komagatella phaffii PEPCK promoter

BackgroundKomagataella phaffii (a.k.a. Pichia pastoris) harbors a glutamate utilization pathway in which synthesis of glutamate dehydrogenase 2 and phosphoenolpyruvate carboxykinase (PEPCK) is induced by glutamate. Glutamate-inducible synthesis of these enzymes is regulated by Rtg1p, a cytosolic, basic helix-loop-helix protein. Here, we report food-grade monosodium glutamate (MSG)-inducible recombinant protein production from K. phaffii PEPCK promoter (PPEPCK) using green fluorescent protein (GFP) and receptor binding domain of SARS-CoV-2 virus (RBD) as model proteins.ResultsPPEPCK-RBD/GFP expression cassette was integrated at two different sites in the genome to improve recombinant protein yield from PPEPCK. The traditional, methanol-inducible alcohol oxidase 1 promoter (PAOX1) was used as the benchmark. Initial studies carried out with MSG as the inducer resulted in low recombinant protein yield. A new strategy employing MSG/ethanol mixed feeding improved biomass generation as well as recombinant protein yield. Cell density of 100–120 A600 units/ml was achieved after 72 h of induction in shake flask cultivations, resulting in recombinant protein yield from PPEPCK that is comparable or even higher than that from PAOX1.ConclusionsWe have designed an induction medium for recombinant protein production from K. phaffii PPEPCK in shake flask cultivations. It consists of 1.0% yeast extract, 2.0% peptone, 0.17% yeast nitrogen base with ammonium sulfate, 100 mM potassium phosphate (pH 6.0), 0.4 mg/L biotin, 2.0% MSG, and 2% ethanol. Substitution of ammonium sulphate with 0.5% urea is optional. Carbon source was replenished every 24 h during 72 h induction period. Under these conditions, GFP and RBD yields from PPEPCK equaled and even surpassed those from PAOX1. Compared to the traditional methanol-inducible expression system, the inducers of glutamate-inducible expression system are non-toxic and their metabolism does not generate toxic metabolites such as formaldehyde and hydrogen peroxide. This study sets the stage for MSG-inducible, industrial scale recombinant protein production from K. phaffii PPEPCK in bioreactors.

Evaluation of the Environmental Impact and Energy Utilization Efficiency of Wastewater Treatment Plants in Tumen River Basin Based on a Life Cycle Assessment + Data Envelopment Analysis Model

The environmental impacts from energy consumption account for a high percentage of the environmental impacts of wastewater treatment plants (WWTPs) throughout their life cycle; therefore, controlling energy use in WWTPs could bring substantial benefits to the environment. In this study, according to the different percentages of electricity generation from renewable energy compared to fossil energy, the global warming, acidification, eutrophication, human toxicity, and photochemical smog, the environmental impacts of WWTP operation were considered. Furthermore, to explore a more sustainable way of operating WWTPs under the “dual-carbon” strategic decision, the environmental impacts and energy utilization efficiency of different power allocation scenarios at present and in the next 40 years were compared based on the LCA+DEA integrated model. The study revealed that in scenarios 1–5, as the proportion of renewable energy power generation gradually increased, all LCA results showed a gradual decrease, of which GWP decreased by 83.32% and human toxicity decreased by 93.34%. However, in scenarios 2–5, the contribution ratio (proportion) of gas and electricity to GWP and POCP gradually increased, reaching 77.11% and 59.44%, respectively, in scenario 5. The contribution ratio (proportion) of biomass generation to AP and EP gradually increased as well, reaching 65.22% and 68.75%, respectively, in scenario 5. Meanwhile, the combined technical efficiency in energy utilization in the five scenarios showed a decreasing trend; only scenario 1 was fully efficient, and the combined efficiency was 1. The values of combined technical efficiency in scenarios 2, 3, 4, and 5 gradually decreased and were 0.7386, 0.4771, 0.2967, and 0.1673, respectively. This study discusses whether the use of renewable energy in place of fossil energy power elicits an environmental impact in WWTPs. We explore the feasibility of achieving energy savings and emission reductions in WWTPs within the Tumen River Basin, to provide a theoretical basis for their sustainable development.

Biophotonic Combined Energy System (BCES)

A comprehensive outline of a new approach in closed loop processing for energy utilisation and biomass genera tion using micro algae for electricity, heat and chemicals is presented - the Biophotonic Combined Energy System (BCES). The basic idea proposes that life-cycle management is an es sential strategy in research and business. In terms of the BCES a carbon cycle driven by solar radiation via the photosystems of the Chlorophyceae species Scenedesmus rubescens serves as the core process from which valuable materials are extracted. The resi dues serve as the substrate for biogas generation which is used to run a Combined Heat and Power Plant (CHP) equipped with a gas motor and an exhaust gas carbon dioxide and heat recovery system. The electricity generated is fed into the public grid and the thermal energy is used to make the right temperature for the micro algae suspension. The carbon dioxide from biogas combus tion is injected into the algae suspension thereby closing the elementary loop within the system.

An Innovative Co-Cultivation of Microalgae and Actinomycete-Inoculated Lettuce in a Hydroponic Deep-Water Culture System for the Sustainable Development of a Food–Agriculture–Energy Nexus

In recent years, researchers have turned their attention to the co-cultivation of microalgae and plants as a means to enhance the growth of hydroponically cultivated plants while concurrently producing microalgal biomass. However, the techniques used require precise calibration based on plant growth responses and their interactions with the environment and cultivation conditions. This study initially focused on examining the impact of hydroponic nutrient concentrations on the growth of the microalga Chlorella sp. AARL G049. The findings revealed that hydroponic nutrient solutions with electrical conductivities (EC) of 450 µS/cm and 900 µS/cm elicited a positive response in microalgae growth, resulting in high-quality biomass characterized by an elevated lipid content and favorable properties for renewable biodiesel. The biomass also exhibited high levels of polyunsaturated fatty acids (PUFAs), indicating excellent nutritional indices. The microalgae culture and microalgae-free culture, along with inoculation-free lettuce (Lactuca sativa L. var. longifolia) and lettuce that was inoculated with plant growth actinobacteria, specifically the actinomycete Streptomyces thermocarboxydus S3, were subsequently integrated into a hydroponic deep-water culture system. The results indicated that several growth parameters of lettuce cultivated in treatments incorporating microalgae experienced a reduction of approximately 50% compared to treatments without microalgae, and lowering EC levels in the nutrient solution from 900 µS/cm to 450 µS/cm resulted in a similar approximately 50% reduction in lettuce growth. Nevertheless, the adverse impacts of microalgae and nutrient stress were alleviated through the inoculation with actinomycetes. Even though the co-cultivation system leads to reduced lettuce growth, the system enables the production of high-value microalgal biomass with exceptional biodiesel fuel properties, including superior oxidative stability (>13 h), a commendable cetane number (>62), and a high heating value (>40 MJ/kg). This biomass, with its potential as a renewable biodiesel feedstock, has the capacity to augment the overall profitability of the process. Hence, the co-cultivation of microalgae and actinomycete-inoculated lettuce appears to be a viable approach not only for hydroponic lettuce cultivation but also for the generation of microalgal biomass with potential applications in renewable energy.

Linking Resource Quality and Biodiversity to Benthic Ecosystem Functions Across a Land-to-Sea Gradient

Benthic macrofauna modifies carbon and nutrient retention and recycling processes in coastal habitats. However, the contribution of benthic consumers to carbon and nutrient storage and recycling shows variation over spatial scales, as the benthic community composition changes in response to differences in environmental conditions. By sampling both shallow sandy and deep muddy sediments across a land-to-sea gradient in the northern Baltic Sea, we explored if benthic community composition, stoichiometry and process rates change in response to alterations in environmental conditions and food sources. Our results show that benthic faunal biomass, C, N, and P stocks, respiration rate and secondary production increase across the land-to-sea gradient in response to higher resource quality towards the open sea. The seston δ13C indicated terrestrial runoff and δ15N sewage input at the innermost study sites, whereas more fresh marine organic matter towards the open sea boosted benthic faunal carbon storage, respiration rate, and secondary production, that is, the generation of consumer biomass, which are essential processes for carbon turnover in this coastal ecosystem. Also, biological factors such as increasing species richness and decreasing biomass dominance of the clam Macoma balthica were significant in predicting benthic faunal C, N, and P stocks and process rates, especially at sandy sites. Interestingly, despite the variation in food sources, the benthic faunal C:N:P ratios remained stable across the gradient. Our results prove that human activities in the coastal area can influence the important links between biodiversity, structure, and process rates of benthic communities by modifying the balance of available resources, therefore hampering the functioning of coastal ecosystems.

Neural Networks for Monitoring Microalgae Biomass in Building Façades

The substantial impact of buildings on CO2 emissions and climate change highlights the urgent need to adopt sustainable measures. Microalgae photobioreactors have shown potential as a renewable feedstock for biomass generation and CO2 absorption. Conventional biomass prediction methods are usually laborious and time-intensive, and sacrifice biomass for measurement. This research addresses these challenges by developing a novel approach using Feed-forward Neural Networks and Convolutional Neural Networks for accurate biomass prediction. Feed-forward Neural Networks demonstrated a positive linear relationship between predicted and valid biomass values of 0.99 on average. Convolutional Neural Networks improved performance over time with an accuracy of up to 97%. This research advanced biomass prediction methodologies and supported optimizing photobioreactors performance for enhanced energy efficiency and biomass generation.

Biomass Storage Potential and Improvement in Soil Properties under Different Bamboo Plantations in the Terai Region of Central Himalaya

This study evaluates six bamboo species, i.e., Dendrocalamus hamiltonii, Bambusa nutans, Dendrocalamus asper, Bambusa bambos, Bambusa balcooa, and Dendrocalamus strictus, regarding their growth behavior, nutrient uptake, and effect on the soil properties of the Terai region. Various aboveground growth parameters exhibited significant variations with the maximum clump girth (8.60 m) and internodal length (35.37 cm) of B. nutans, which was also reported by the culm diameter (5.70 cm) of D. hamiltonii and the number of culms per clump (65) of D. strictus. The total aboveground biomass ranged from 51.14 Mg.ha-1 in D. asper to 362.56 Mg.ha-1 in D. hamiltonii. The most significant variation in soil properties was observed in the 0-40 cm soil layer. Under D. hamiltonii, the lowest soil bulk density (1.07 g.cm3; 1.21 g.cm3) and the maximum soil porosity (59.00%; 56.40%), soil organic carbon (1.54%; 0.72%), and available soil nitrogen (228.29 kg.ha-1; 173.73 kg.ha-1) were found the 0-40 and 40-80 cm soil layers. Furthermore, significant enhancements in soil microbial population were recorded. Thus, bamboo plantations have great potential to enhance the biomass generation and fertility quotient of fallow lands.

Chlamydomonas reinhardtii and Microbacterium forte sp. nov., a mutualistic association that favors sustainable hydrogen production

A naturally occurring multispecies bacterial community composed of Bacillus cereus and two novel bacteria (Microbacterium forte sp. nov. and Stenotrophomonas goyi sp. nov.) has been identified from a contaminated culture of the microalga Chlamydomonas reinhardtii. When incubated in mannitol- and yeast extract-containing medium, this bacterial community can promote and sustain algal hydrogen production up to 313 mL H2·L−1 for 17 days and 163.5 mL H2·L−1 for 25 days in high-cell (76.7 μg·mL−1 of initial chlorophyll) and low-cell density (10 μg·mL−1 of initial chlorophyll) algal cultures, respectively. In low-cell density algal cultures, hydrogen production was compatible with algal growth (reaching up to 60 μg·mL−1 of chlorophyll). Among the bacterial community, M. forte sp. nov. was the sole responsible for the improvement in hydrogen production. However, algal growth was not observed in the Chlamydomonas-M. forte sp. nov. consortium during hydrogen-producing conditions (hypoxia), suggesting that the presence of B. cereus and S. goyi sp. nov. could be crucial to support the algal growth during hypoxia. Still, under non‑hydrogen producing conditions (aerobiosis) the Chlamydomonas-M. forte sp. nov. consortium allowed algal growth (up to 40 μg·mL−1 of chlorophyll) and long-term algal viability (>45 days). The genome sequence and growth tests of M. forte sp. nov. have revealed that this bacterium is auxotroph for biotin and thiamine and unable to use sulfate as sulfur source; it requires S-reduced forms such as cysteine and methionine. Cocultures of Chlamydomonas reinhardtii and M. forte sp. nov. established a mutualistic association: the alga complemented the nutrient deficiencies of the bacterium, while the bacterium released ammonium (0.19 mM·day−1) and acetic acid (0.15 mM·day−1) for the alga. This work offers a promising avenue for photohydrogen production concomitant with algal biomass generation using nutrients not suitable for mixotrophic algal growth.

Recycling Ophthalmic Lens Wastewater in a Circular Economy Context: A Case Study with Microalgae Integration.

Water pollution poses a global threat to ecosystems and human health and is driven by the presence of various contaminants in wastewater, including nano- and microplastics. Despite the magnitude of this problem, the majority of global wastewater is released untreated into water bodies. To combat this issue, a multi-strategy approach is needed. This study explores a circular economy-based solution for treating emerging pollutants, particularly wastewater from ophthalmic spectacle lens production. Our approach integrates solid waste materials into polymeric and cement matrices while also utilising wastewater for microalgae cultivation. This innovative strategy focuses on biomass generation and economic valorisation. By adopting a circular economy model, we aim to transform environmental pollutants from wastewater into valuable organic products. A key component of our approach is the utilisation of microalgae, specifically Nannochloropsis sp., known for its high lipid content and resilience. This microalgae species serves as a promising biobased feedstock, supporting the production of innovative biobased products, such as biopolymers, for ophthalmic lens manufacturing. Our interdisciplinary approach combines microalgae technology, analytical chemistry, cement production, and polymer processing to develop a sustainable circular economy model that not only addresses environmental concerns, but also offers economic benefits. This study underscores the potential of harnessing high-value products from waste streams and underscores the importance of circular economy principles in tackling pollution and resource challenges.

Effects of temperature, pH, and C/N ratio of sugarcane wastewater processing (vinasse) on Phormidium autumnale heterotrophic cultivation

Agro-industrial wastewater treatment processes using microalgae have been attractive due to high commercial-value biomass obtainment and contaminant removal efficiency. Cyanobacteria cultivation with the generation of biomass and bioproducts, such as proteins, lipids, carbohydrates, and pigments, is known by the term microalgae biorefinery. In this context, the present study aimed to heterotrophically cultivate Phormidium autumnale in sugarcane vinasse and evaluate its contaminant removals, emphasizing its value-added bioproduct production. The highest biomass productivity was reached at 35 °C, corresponding to 127.20 mg L−1 d−1, in a C/N ratio of 16 and pH of 7.5, with removals of organic carbon, nitrogen, and phosphorus of 49 %, 47 %, and 28 % respectively. In the batch cultivation, removals of organic carbon (67 %) and nitrogen (70 %) were obtained, with maximum productivity in terms of biomass equivalent to the best performance of the tests performed on an orbital shaker (CCRD). Biomass generated by P. autumnale showed 21.33 % proteins, 4.26 % lipids, 197.53 mg g−1 blue phycocyanin pigment, and a varied carbohydrate composition, such as glucose (79.46 mg L−1), arabinose (44.53 mg L−1), mannose (9.84 mg L−1), galactose (2.76 mg L−1), and xylose (14.44 mg L−1). These monosaccharides are ideal in the formation of exopolysaccharides (EPS) and 0.91 g L−1 of total reducing sugars (TRS). Our results demonstrated the ability of P. autumnale to treat sugarcane vinasse, which becomes a medium for its cultivation, removing representative amounts of carbon and nitrogen, besides producing several bioproducts, such as proteins, lipids, phycocyanin pigment, and carbohydrates.

Serine synthesis pathway enzyme PHGDH is critical for muscle cell biomass, anabolic metabolism, and mTORC1 signaling.

Cells use glycolytic intermediates for anabolism, e.g., via the serine synthesis and pentose phosphate pathways. However, we still understand poorly how these metabolic pathways contribute to skeletal muscle cell biomass generation. The first aim of this study was therefore to identify enzymes that limit protein synthesis, myotube size, and proliferation in skeletal muscle cells. We inhibited key enzymes of glycolysis, the pentose phosphate pathway, and the serine synthesis pathway to evaluate their importance in C2C12 myotube protein synthesis. Based on the results of this first screen, we then focused on the serine synthesis pathway enzyme phosphoglycerate dehydrogenase (PHGDH). We used two different PHGDH inhibitors and mouse C2C12 and human primary muscle cells to study the importance and function of PHGDH. Both myoblasts and myotubes incorporated glucose-derived carbon into proteins, RNA, and lipids, and we showed that PHGDH is essential in these processes. PHGDH inhibition decreased protein synthesis, myotube size, and myoblast proliferation without cytotoxic effects. The decreased protein synthesis in response to PHGDH inhibition appears to occur mainly mechanistic target of rapamycin complex 1 (mTORC1)-dependently, as was evident from experiments with insulin-like growth factor 1 and rapamycin. Further metabolomics analyses revealed that PHGDH inhibition accelerated glycolysis and altered amino acid, nucleotide, and lipid metabolism. Finally, we found that supplementing an antioxidant and redox modulator, N-acetylcysteine, partially rescued the decreased protein synthesis and mTORC1 signaling during PHGDH inhibition. The data suggest that PHGDH activity is critical for skeletal muscle cell biomass generation from glucose and that it regulates protein synthesis and mTORC1 signaling.NEW & NOTEWORTHY The use of glycolytic intermediates for anabolism was demonstrated in both myoblasts and myotubes, which incorporate glucose-derived carbon into proteins, RNA, and lipids. We identify phosphoglycerate dehydrogenase (PHGDH) as a critical enzyme in those processes and also for muscle cell hypertrophy, proliferation, protein synthesis, and mTORC1 signaling. Our results thus suggest that PHGDH in skeletal muscle is more than just a serine-synthesizing enzyme.

Biomass production, carbon stock and sequestration potential of prominent agroforestry systems in north-western Himalaya, India

Agroforestry is an age-old practise of integrating farming with practises, preferably on the same unit of land on sustainable basis. There is tremendous scope for Agroforestry because India has achieved self-sufficiency in food production. Now its attention is becoming more focused on the ecological problems and shortage of fuel, fodder and other outputs as well as unemployment. So, agroforestry land use systems offer a better option by serving as carbon sinks and contributing in attaining food safety, subsistence income, and habitat amelioration. The current study was conducted in this context in the south Kashmir area of India with the objective of recognising the capability of various agroforestry systems for biomass estimation and carbon sequestration assessment for mitigating climate variation. The present study entitled “Biomass production, carbon stock and sequestration potential of prominent agroforestry systems in North-western Himalaya, India” was carried out, during 2018–2019. The study site is located between 33° 72’N and 75° 14’E at an altitude ranging from 2,900 to 5,900 M (amsl). Multistage random sampling technique was used for selection of sampled tehsils, blocks, villages and farmers in Anantnag district. The first stage was the random sampling of six tehsils namely Anantnag, Shangus, Kokernag, Dooru, Sallar, and Larnu and blocks per tehsil namely, viz.; Anantnag, Shangus, Sagam, Shahabad, Pahalgam and Larnu. Then four villages within each block like Anantnag (Ruhoo, Dialgam, Wanihama and Donipawa), Shangus (Shangus, Nowgam, Kutheir and Andoora), Sagam (Hiller, Khalhar, Sagam and Bidder), Shahabad (Larkipora, Shankerpora, Nathipora and Bragam), Pahalgam (Yanner, Charigam, Movra and Wahdan) and Larnu (Leesu, Dandipora, Bidhard and Larnu). Ten farmers within each village were selected, thus making a total of 240 farmers, which accounts 25% sampling intensity. Four agroforestry systems including horti-agriculture, agrisilviculture, (boundary planting), agri-horti-silviculture and horti-silvipasture were chosen for the study as the experimental configuration. Maximum biomass was found in horti-silvipastoral contributing 66.55 t ha−1 followed by agri-horti-silviculture as 50.18 t ha−1, horti-agriculture as 36.22 t ha−1 and agri-silviculture as 34.87 t ha−1. The maximum mean biomass of fruit trees (30.54 t ha−1), forest trees (25.19 t ha−1), grass (7.18 t ha−1) during the first cut and 3.64 t ha−1 during the second cut, was calculated in horti-silvipasture system. The overall biomass output of diverse agroforestry systems goes along with the sequence: horti-silvipasture > agri-horti-silviculture > horti-agriculture > boundary plantation, respectively. As a result, estimates of carbon stocks and carbon sequestration for all systems showed the same trend as values for biomass since they are both directly related to the capacity for biomass generation of various plant components. By providing for rural livelihoods and serving as an efficient carbon sink through carbon sequestration, these agroforestry systems in the Himalayas can significantly increase total production and productivity. The results of the current study could have a big impact on how alternative agroforestry systems and tree combinations are chosen for efficient carbon budget management in delicate Himalayan ecosystems.

Biomass Energy Potential of Agricultural Residues in the Dominican Republic

The Dominican Republic has significant potential for energy generation from residual biomass, with sugarcane, rice, and coconut waste having the highest energy potential. The Eastern, Northeastern, and Southern regions were identified as the areas with the most significant potential for energy generation. This potential can be harnessed to complement intermittent or unmanageable renewable energies in distributed generation networks. Biomass generation plants can be hybridized with other sources, such as wind and solar, to provide a more stable and reliable electricity supply. The methodology developed to evaluate the energy potential of residual biomass in the Dominican Republic integrates a rigorous review of the literature and agricultural databases, incorporating criteria such as annual production, residue-to-product ratio, higher calorific value, and dry matter content, culminating in a formula that synthesizes normalized data to optimize the selection and projection of biomass sources based on their potential energy contribution. The study found that the Dominican Republic has significant potential for energy generation from residual biomass, which can be leveraged to provide a more stable and reliable electricity supply.

Plastic bio-mitigation by Pseudomonas mendocina ABF786 and simultaneous conversion of its CO2 byproduct to microalgal biodiesel

Bio-mitigation of plastics by microorganisms generates carbon dioxide (CO2) that can be utilized for algal biomass generation. Pseudomonas mendocina ABF786, reportedly the most efficient plastic-degrading bacteria, was screened using the modified most probable number technique. This study highlights the use of an integrative prototype for the production of microalgal biomass (Chlorella vulgaris) in combination with bio-mitigation of plastics, which serves a dual purpose: (i) increased plastic-degradation capability by microorganisms (53%–85% increase in plastic weight loss) due to removal of CO2 feedback inhibition and (ii) increased algal biomass generation (200%–237%) due to supply of extra CO2 from plastic degradation to the algal cultivation flask. Whole-genome sequencing and functional annotation confirmed that all the genes involved in the mineralization of plastic to CO2 are present within the genome of P. mendocina ABF786. Using two or more microbial cultures for remediation may increase the process efficiency.

Comprehensive environmental and techno-economic feasibility assessment of biomass- solar on grid hybrid power generation system for Burdur Mehmet Akif Ersoy University Istiklal Campus

The worldwide use of clean and environmentally friendly renewable energy sources, has been increasing to prevent global warming and climate change. In this study, a hybrid renewable energy system (HRES) including biomass and solar as the source, has been investigated for Mehmet Akif Ersoy University Istiklal Campus in Burdur, Türkiye. The campus has an animal farm consisting of 300 cattle and 200 sheep. Therefore, manure of the animals will be used as the resource for biomass generation. HOMER software is used to simulate the system and to find the size and the quantity of the equipment according to the meteorological and biomass capacity of the campus. The optimum system is determined by means of net present cost (NPC) and the cost of energy (COE). In the simulation, wind energy is also investigated but since the wind speed is not sufficient to produce energy in the region, it is not considered in the optimum system. The optimum system is determined to be grid connected biomass-solar system with 5000 kW PV panels and a 1500 kW biomass generator assisted by the grid of 3000 kW. Also, the NPC of the system is estimated to be USD 18.800.000 and the COE for the system is calculated as 0,107 USD/kWh. The system also reduces the emissions causing the global warming.

Respiration is essential for aerobic growth of Zymomonas mobilis ZM4.

A key to producing next-generation biofuels is to engineer microbes that efficiently convert non-food materials into drop-in fuels, and to engineer microbes effectively, we must understand their metabolism thoroughly. Zymomonas mobilis is a bacterium that is a promising candidate biofuel producer, but its metabolism remains poorly understood, especially its metabolism when exposed to oxygen. Although Z. mobilis respires with oxygen, its aerobic growth is poor, and disruption of genes related to respiration counterintuitively improves aerobic growth. This unusual result has sparked decades of research and debate regarding the function of respiration in Z. mobilis. Here, we used a new set of mutants to determine that respiration is essential for aerobic growth and likely protects the cells from damage caused by oxygen. We conclude that the respiratory pathway of Z. mobilis should not be deleted from chassis strains for industrial production because this would yield a strain that is intolerant of oxygen, which is more difficult to manage in industrial settings.

Effect of Solid-state Fermentation Parameters on Growth of Interest and Environmental Enzyme Production with Aspergillus niger

Using residual biomass in biological processes is increasingly promoted to alleviate environmental impacts. However, the focus is mainly based on emerging technologies and limited resources, and the conditions of the technologies remain unclear. The objective of this research is to establish the conditions of a solid-state fermentation system (SSF) for the growth of fungal biomass and the production of ligninolytic enzymes of environmental interest using Aspergillus niger. In a screening step, the biomass and lipase enzyme expression of three A. niger strains obtained from different screening sites will be extended. In the second stage, the effect of packing density (ρs) and airflow (vvm) was evaluated through a 23, on the growth of fungal biomass, fiber degradation, and CO2 generation in a lipid-contaminated SSF system. The generation of biomass and the concentration of specific enzymatic activity (U/L) of lipase present a correlation for all the strains evaluated. It was estimated that the A. niger strain AN19bc isolated from sugarcane bagasse presents the highest accumulation of biomass and concentration of specific enzyme activity of lipase (0.027 U/L) after nine days. The most appropriate conditions for the production of fungal biomass of the AN19bc strain in an SSF system are presented with an airflow of 33.33 vvm and packing density ρs = 360 kg Mss/m3, levels with which Yx/s= 0.91 is reached. After the process, the solid support used in the SSF presents a change in composition, with the fiber being the component that suffers a considerable degradation of 78.70%.

Current Insights into Growing Microalgae for Municipal Wastewater Treatment and Biomass Generation

Municipal wastewater (MWW) provides a promising platform for microalgae cultivation due to its rich content of essential nutrients. Recent research has showcased the multifaceted benefits of microalgae-based wastewater treatment, from the potent depollution capabilities of these organisms to their biomass potential for ecofriendly applications. A significant advantage lies in the ability of these systems to promote environmental sustainability without producing secondary pollutants, aligning with the circular economy model. This approach encompasses various stages, from cultivating microalgae to biomass separation and subsequent valorization. However, challenges arise when scaling these systems to industrial levels. A predominant barrier is the difficulty in maintaining consistent control over all the factors influencing wastewater phytoremediation. This can compromise both biomass survival and the efficiency of pollution removal and valorization. Notably, using native microalgal consortiums from the effluent appears to be a promising strategy. These autochthonous communities often demonstrate superior adaptability and treatment capacity, emphasizing the importance of further exploring their potential to provide effective and economically viable solutions for wastewater treatment.

Effect of pharmaceutical and domestic wastewater mixed ratios on microalgal growth for nutrients removal coupled with biomass and liquid biofuel generation

Effect of pharmaceutical and domestic wastewater mixed ratios on microalgal growth for nutrients removal coupled with biomass and liquid biofuel generation