Optimal Biomass Research Articles

Evaluation of environmental parameters for optimal cell density, biomass, lipid, and biodiesel production in scenedesmus: Focus on suspension and biofilm methods

The study focused on investigating the impact of various environmental parameters on the production of Scenedesmus, a unicellular alga known for its industrial and food value. The parameters studied included production method, temperature, lighting period, light intensity, and pH, with a particular emphasis on suspension and biofilm production methods. The results highlighted optimal conditions for different aspects of production, such as cell density, biomass production, lipid production, and biodiesel production. Specifically, the findings indicated that the highest cell density was achieved at a temperature of 25 °C, light intensity of 3000 lux, lighting period of 16 h, and pH of 8. For biomass production, the optimal conditions were a temperature of 25 °C, light intensity of 3000 lux, lighting period of 18 h, and pH of 9. The greatest lipid production was observed at a temperature of 20 °C, light intensity of 4000 lux, lighting period of 18 h, and pH of 8. Moreover, the highest biodiesel production was recorded at a temperature of 25 °C, light intensity of 3000 lux, lighting period of 18 h, and pH of 8. Notably, the study found that the biofilm production method outperformed the suspension method across various parameters, including cell density, biomass production, lipid production, and biodiesel production. These results contribute to the existing knowledge of optimal conditions for microalgae production and underscore the potential of Scenedesmus in industrial and food applications.

Investigation on Synergism and Its Influence Parameters between Coal and Biomass during Co-Gasification Based on Aspen Plus

The co-gasification of coal and biomass offers numerous benefits, including improved gasification efficiency, reduced pollution emissions, and the utilization of renewable resources. However, there is a lack of comprehensive research on the synergistic effects of, and influence parameters on, coal–biomass co-gasification. This study employs Aspen Plus simulations to investigate the co-gasification behavior of coal and corn straw, focusing on the synergistic effects and the impact of various operating conditions. A synergistic coefficient is defined to quantify the interactions between the feedstocks. Sensitivity analyses explore the effects of gasification temperature (800–1300 °C), coal rank (lignite, bituminous, anthracite), biomass mass fraction (0–50%), oxygen-to-carbon ratio, and steam-to-carbon ratio on the synergistic coefficients of effective syngas content (CO + H2), specific oxygen consumption, specific fuel consumption, and cold gas efficiency. The results reveal an optimal biomass mass fraction of 10% for maximizing cold gas efficiency, with the syngas primarily consisting of H2 (36.8%) and CO (61.6%). Higher gasification temperatures (up to 1200 °C) improve syngas quality and process efficiency, while higher-rank coals exhibit better gasification performance compared to lignite. Optimal oxygen-to-carbon and steam-to-carbon ratios are identified for maximizing syngas yield and quality. These findings provide valuable guidance for the design and optimization of industrial coal–biomass co-gasification processes, enabling the maximization of syngas quality, process efficiency, and resource utilization.

Bioremoval of Contaminated in Wastewater by Using Alginate Immobilized Cell of Green Microalga Nannochloropsis oculata

The optimum conditions and adsorption kinetic for bioremoval of benefix red by immobilized cell of Nannochloropsis oculata were studied. The results showed that the optimum pH for bioremoval of dye was at 2 with the highest adsorption capacity of 0.90±0.01 mg/g. The equilibrium time of adsorption was 2 h with adsorption capacity of 1.80±0.02 mg/g. The optimum biomass was 2 g/l with adsorption capacity of 3.98±0.02 mg/g. The adsorption capacity (qeq) decreased when the algal biomass increased. The adsorption characteristics fitted well with the Langmuir adsorption isotherm with maximum adsorption capacity (Qmax) of 106.58±20.22 mg/g. Dye removal correlated with pseudo first-order, while the adsorption rate was limited by film and intraparticle diffusion at secondary step. It can be concluded that alginate immobilized cell of N. oculata may be used as an alternative for removal of benefix red contaminated in wastewater.

Flux Balance Analysis Reveals Potential Anti–HIV-1 Metabolic Targets

Abstract Background Human immunodeficiency virus type 1 (HIV-1) remains a persistent global health challenge. Therefore, a continuous exploration of novel therapeutic strategies is essential. A comprehensive understanding of how HIV-1 utilizes the cellular metabolism machinery for replication can provide insights into new therapeutic approaches. Methods In this study, we performed a flux balance analysis using a genome-scale metabolic model (GEM) integrated with an HIV-1 viral biomass objective function to identify potential targets for anti–HIV-1 interventions. We generated a GEM by integrating an HIV-1 production reaction into CD4+ T cells and optimized for both host and virus optimal states as objective functions to depict metabolic profiles of cells in the status for optimal host biomass maintenance or for optimal HIV-1 virion production. Differential analysis was used to predict biochemical reactions altered optimal for HIV-1 production. In addition, we conducted in silico simulations involving gene and reaction knock-outs to identify potential anti–HIV-1 targets, which were subsequently validated by human phytohemagglutinin (PHA) blasts infected with HIV-1. Results Differential analysis identified several altered biochemical reactions, including increased lysine uptake and oxidative phosphorylation (OXPHOS) activities in the virus optima compared with the host optima. In silico gene and reaction knock-out simulations revealed de novo pyrimidine synthesis, and OXPHOS could serve as potential anti–HIV-1 metabolic targets. In vitro assay confirmed that targeting OXPHOS using metformin could suppress the replication of HIV-1 by 56.6% (385.4 ± 67.5 pg/mL in the metformin-treated group vs. 888.4 ± 32.3 pg/mL in the control group, P < 0.001). Conclusion Our integrated host-virus genome-scale metabolic study provides insights on potential targets (OXPHOS) for anti-HIV therapies.

Analysis of the remediation competence of Aspergillus flavus biomass in wastewater of the dyeing industry: An in-vitro study

The dyeing industry effluent causes severe environmental pollution and threatens the native flora and fauna. The current study aimed to analyze the physicochemical parameters of dyeing industry wastewater collected in different sites (K1, E2, S3, T4, and V5), as well as the metal tolerance and decolourisation ability of Aspergillus flavus. Furthermore, the optimal biomass quantity and temperatures required for efficient bioremediation were investigated. Approximately five dyeing industry wastewater samples (K1, E2, S3, T4, and V5) were collected from various sampling stations, and the majority of the physical and chemical characteristics were discovered to be above the permissible limits. A. flavus demonstrated outstanding metal resistance to As, Cu, Cr, Zn, Hg, Pb, Ni, and Cd on Potato Dextrose Agar (PDA) plates at concentrations of up to 500 g mL−1. At 4 g L−1 concentrations, A. flavus biomass decolorized up to 11.2–46.5%. Furthermore, 35°C was found to be the optimal temperature for efficient decolourisation of A. flavus biomass. The toxicity of 35°C-treated wastewater on V. mungo and prawn larvae was significantly reduced. These findings indicate that the biomass of A. flavus can be used to decolorize dyeing industry wastewater.

Evaluating the Research Status of the Remote Sensing-Mediated Monitoring of Forest Biomass: A Bibliometric Analysis of WOS

Forests serve as the largest carbon reservoir in terrestrial ecosystems, playing a crucial role in mitigating global warming and achieving the goal of “carbon neutrality”. Forest biomass is intrinsically related to carbon sinks and sources in forest ecosystems, and thus, the accurate monitoring of forest biomass is of great significance in ensuring ecological security and maintaining the global carbon balance. Significantly, remote sensing is not only able to estimate forest biomass at a large spatial scale but does so quickly, accurately, and without loss. Moreover, it can obtain forest biomass in areas inaccessible to human beings, which have become the main data source for forest biomass estimation at present. For this reason, this study analyzes the current research status, research hotspots, and future research trends in the field of remote sensing monitoring of forest biomass based on 1678 forest biomass remote sensing monitoring results from 1985 to 2023 obtained from the Web of Science Core Collection database. The results showed that the following: (1) The number of publications showed an exponential upward trend from 1985 to 2023, with an average annual growth rate of 2.64%. The top ten journals contributed to 53.76% of the total number of publications and 52.89% of the total number of citations in the field. (2) In particular, Remote Sensing of Environment has maintained a leading position in the field for an extended period, boasting the highest impact factor. Additionally, the author Saatchi S. stands out with the highest total number of citations for articles. (3) Keyword clustering analysis revealed that the main research topics in the remote sensing monitoring of forest biomass can be categorized into the following: optical remote sensing, LiDAR remote sensing, SAR remote sensing, and carbon stock. The explosion of keywords in the last six years indicates that an increasing number of researchers are focusing on carbon, airborne LiDAR data, biomass mapping, and constructing optimal biomass models.

Microalgal-bacterial immobilized co-culture as living biofilters for nutrient recovery from synthetic wastewater and their potential as biofertilizers

This study investigates nutrient recovery from synthetic municipal wastewater using co-immobilized cultures of Chlorella vulgaris TISTR 8580 (CV) and plant growth-promoting bacteria, Bacillus subtilis TISTR 1415 (BS) as living biofilters for a subsequent biofertilizer activity. The optimal condition for nutrient recovery was at the 1:1 ratio of CV/BS using mixed guar gum/carrageenan (GG/CG) binders. After 7-day wastewater treatment, the living biofilters removed 86.7 ± 0.5% of ammonium and 99.3 ± 0.3% of phosphates and were tested subsequently as biofertilizers for 20 days to grow selected plants. The highest optimal biomass and chlorophyll a content was 2 ± 0.3 g (CV/BS 3:1) and 12.4 ± 0.7 µg/g (CV/BS 1:1) from cucumber respectively, however, the close-to-neutral pH (8.0 ± 0.3) was observed from sunflower using CV/BS 1:1 living biofilters. Conclusively, the designed living biofilters exhibit the potential to recover nutrients from wastewater and be used as biofertilizers for circular agriculture.

Exploring the Production of Secondary Metabolites from a Halophyte Tetragonia tetragonoides through Callus Culture

Considering Korea’s gradual shift toward an aging society, consumer interest in compounds with physiological benefits, including antioxidant and anticancer effects, has surged. This study explored the potential of Tetragonia tetragonoides (Pall.) Kunze, commonly known as New Zealand Spinach (NZS), a halophyte with reported health benefits, including efficacy in treating gastrointestinal diseases, high blood pressure, diabetes, and obesity. This study also introduced a novel callus culture system for NZS, allowing for the rapid in vitro production of secondary metabolites. Optimal callus induction (100%) and biomass production (0.416 g) were achieved by adding 2.0 mg·L−1 6-BA (6-Benzylaminopurine) and 0.5 mg·L−1 2,4-D (2,4-Dichlorophenoxyacetic acid) among five auxin and cytokinin combinations. Two distinct callus types, TGC [TDZ (Thidiazuron)-supplemented Green Callus] and TNYC [TDZ + NAA (Naphthalene acetic acid)-supplemented Yellow Callus], were identified, each with unique characteristics. The calli showed total phenolic and flavonoid contents comparable to those of NZS leaves grown in the greenhouse. An expression analysis of six genes (CHS, CHI, F3H, F3′H, FLS, and DFR) involved in the kaempferol biosynthesis revealed an enhanced flavonoid biosynthesis-related gene expression in TGC, emphasizing its potential for compound production. GC-MS analysis identified distinct compound profiles in TGC and TNYC, with 2,3-butanediol and succinic acid being the predominant compounds among the nine and forty-four components, respectively. These calli offer a stable supply of functional compounds and present an environmentally sustainable solution. The derived callus culture system is anticipated to contribute to the development of healthy functional foods or pharmaceuticals from halophyte NZS.

The Effect of Callus Age on Biomass and Flavonoid Production in Talinum paniculatum In Vitro Culture

Talinum paniculatum (Javanese Ginseng) is an herbaceous plant belonging to Talinaceae family that has been known as an important medicinal plant. Flavonoid is one of the prominent bioactive compounds that are contained in all parts of T. paniculatum and has been known for its several bioactivities, including antioxidant, anti-inflammatory, antimicrobial, antidiabetic, and anti-cancer. Callus culture can be used to ensure the quantity and quality of flavonoid production. Callus age is one of the important factors that needs to be considered in order to produce optimum biomass and flavonoid production. Therefore, this research aimed to investigate the effect of callus age on biomass and flavonoid production in T. panicultaum in vitro culture. Young leaves were used as an explant, and callus induction was performed using MS solid media supplemented with kinetin 3 mg/L and 2.4-D 2 mg/L. Biomass and flavonoid production were observed during 0, 28, 35, 42, and 49 days. Results showed that biomass and flavonoid production were influenced by callus age. The production of flavonoid in T. paniculatum callus culture was not linear with the growth of callus (biomass), and the optimum flavonoid production resulted in the 28th days of callus age (49.100 mg QE/g), while the optimum biomass resulted in the 49th days of callus age (4.295 g). It can be concluded that the optimum conditions for biomass and flavonoid production in T. paniculatum callus culture are influenced by different callus ages

Identification of exopolysaccharide synthesizing genes in bacteria isolated from Bonny River in Rivers State, Nigeria

Microbial polysaccharide is the most important biopolymer secreted either by bacteria, fungi, or yeast as natural non-toxic, biodegradable and renewable sugar monomers. Microbial EPS owing to their interesting physicochemical and rheological properties has a wide range of industrial application such as in pharmaceuticals, cosmetics, food and Microbial enhanced oil recovery. This study was aimed to identify exopolysaccharide synthesizing genes in three bacterial isolates from Bonny River in Rivers State, Nigeria. The bacterial isolates were identified using the 16S rRNA gene sequence of the strains which carefully studied by making reference to the GenBank database using a BLAST search as Bacillus xiamensis, Bacillus safensis and Exiguobacterium aurantiacum using 16S rRNA PCR technique. Two priming Gylcosyltranferase genes (pGT) rfbp and cpsD were probed in the genome of the isolates after identification of the isolates. Two isolates Bacillus safensis and Exiguobacterium aurantiacum had both rfbp and cpsD genes while Bacillus xiamensis had only rfbp gene but no cpsD gene. The three isolates were examined for the Exopolysaccharide production on a minimal medium that contained g/l: KH2PO4 0.2, K2HPO4 1.5, MgSO4.7H2O 0.2, CaSO4.2H2O 0.1, FeCl3 0.002, yeast extract 0.5 and sucrose 20 and all three isolates produced EPS. At Optimum biomass of 0.15g/10 ml, the highest EPS yield of 10.20 g/l was obtained from Bacillus safenis. Exiguobacterium aurantiacum had optimum biomass of 0.11g/10ml with an EPS yield of 6.15g/l. The least biomass of 0.08g/10ml and EPS yield of 3.62 g/10ml was observed in Bacillus xiamensis. The biomass production was determined at Optical Density (OD) of 600nm while the EPS production was quantified by the Phenol Sulphuric acid method using glucose as a standard.

Effect of Water Sources on the Growth Performance and Chlorophyll Content of Azolla pinnata R.Br.


 
 
 Azolla pinnata R.Br. is an aquatic fern that grows on the surface of water bodies. The unique quality of A. pinnata is its symbiotic relationship with a prokaryotic cyanobacterium (Anabaena azollae), which confers a high rate of nitrogen fixation. It is important to find the growing conditions of Azolla in different water sources for its optimum biomass production for different usages such as biofertilizers, animal feeds, water purification and biofuel production. This preliminary study was conducted to investigate the effect of water sources on the growth performance (shoot biomass, root biomass, root length), and the chlorophyll content of Azolla. Presence of Anabaena in Azolla fronds was monitored by light microscope and number of filaments were counted per leaflet. The experiment utilized three types of water sources (tap water as control (T1), lake water (T2) and cattle manure mixed tap water (T3), in plastic buckets with 40 cm in diameter and 25 cm in height. Each treatment was triplicated in a completely randomized design and total biomass was collected weekly. Data were statistically analyzed using Minitab 17. The highest biomass of Azolla was obtained in T3 from the first week until 8th week and it was higher from T1 and T2. The highest chlorophyll content was obtained in T3 (6.4 SPAD value) showed a significant difference from T1 and T2 (p<0.05). The dry weight of roots and root length in T1 showed a significant difference from T2 and T3 (p<0.05). The highest root length was observed as 5 cm in T1 indicating that roots may be in search of nutrients and the lowest root length was observed as 0.8 cm in T3 with high nutrient concentrations in water. The highest number of Anabaena was observed in the leaflet of Azolla fronds in T3 which in turn increase N content in Azolla plants. It reveals that application of cattle manure in tap water significantly affects the plant biomass and the chlorophyll content of Azolla. Further studies are needed to conduct in large scale growing facilities with different nutrient concentrations of water sources to find sustainable and optimum growing conditions for Azolla and the nutrient concentrations of the plants.
 Keywords: Azolla, Chlorophyll, Growth performance, Water sources
 
 

A new isolate cold-adapted Ankistrodesmus sp. OR119838: influence of light, temperature, and nitrogen concentration on growth characteristics and biochemical composition using the two-stage cultivation strategy.

Natural-based chemicals from microalgae such as lipids and pigments are the interests in industries and the bioeconomy. Cold-adapted Ankistrodesmus sp. OR119838, an isolated strain from Cheshmeh-Sabz Lake in northeastern Iran, was cultivated using a two-stage culture strategy under different environmental conditions. With doubling the nitrate concentration at the vegetative stage (170mg/L) and increasing the light intensity (180µmol photons/m2/s) the highest specific growth rate (0.61 ± 0.02 per day) and biomass productivity (121.1 ± 7.2 mg/L/day) were observed at 25°C. In the optimal growth condition Chl a and Chl b contents of Ankistrodesmus sp. OR119838 reached the highest amount (11.07 ± 0.14 and 11.23 ± 0.29 µg/mL, respectively) at 25°C. While carotenoid content correlated negatively with optimum biomass productivity (-0.708) and had the best value (12.23 ± 0.29µg/mL) in nitrogen deficiency (42 mg/L) and intense light conditions (180µmol photons/m2/s) at 15°C. Lipid content was increased with declined nitrate concentration (42mg/L), high light intensity, and 180µmol photons/m2/s at 25°C. The highest percentage of polyunsaturated fatty acids (71.94%) and α-linolenic acid (57.73 ± 6.63%) was observed in conditions with 170mg/L nitrate concentration and low light intensity (40µmol photons/m2/ s) at the low temperature (15°C). While saturated fatty acids content (43.27%) and palmitic acid reached the highest amount under 40µmol photons/m2/s, 42mg/L nitrate at 25°C (35.02 ± 5.33%). Biomass productivity of Ankistrodesmus sp. OR119838, as a cold-adapted strain, decreased by only 8.2% with a 10-degree decline in temperature. Therefore, this strain has good potential to grow in open ponds by tolerating the daily temperature fluctuations.

Maximizing hydrogen-rich syngas production from rubber wood biomass in an updraft fluidized bed gasifier: An advanced 3D simulation study

BackgroundThis research focuses on biomass gasification as a solution to the global energy crisis. The study aims to optimize the production of syngas by simulating an updraft fluidized bed gasifier using rubber wood as fuel. The goal is to maximize CO and H2 at the gasifier outlet by investigating different vertical positions and angles of the biomass feed inlet. MethodsThe research utilizes 3D simulation and Computational Fluid Dynamics (CFD) through the implementation of the ANSYS Fluent® software package. Realistic assumptions and the K-epsilon turbulence model simplify the analysis. The model assumes a steady state, adiabatic conditions, homogeneous gas phase kinetics, and ideal fluid behavior. Significant findingsThe optimal biomass feed inlet position is 200 mm, yielding higher CO, while a position of 250 mm produces more H2. A 45° feed inlet angle slightly improves syngas quantities but increases CO2. Using a gasifying agent with higher CO2 enhances combustion, while limited O2 facilitates gasification. Increasing oxygen content from 20 % to 50 % raises H2O content. More steam in the inlet boosts H2 production, but excessive H2O reduces steam quality, making expensive steam less effective than air. These findings offer valuable insights for optimizing fluidized bed biomass gasification systems.

Towards a Bioeconomy: Supplying Forest Residues for the Australian Market

Australia has abundant volumes of forest residues that are a potential feedstock for supplying biomass as a renewable carbon carrier to the market. However, there remains an underutilization of this resource, even in mature bioeconomy markets. Several existing or perceived barriers can be attributed to the underdeveloped, forest-based bioeconomy in Australia. One of these is the limited understanding of feedstock supply costs. In this study, two ranking approaches were applied to identify the optimal biomass feedstock supply chain from field to conversion plant gate. A panel of experts embedded in the Australian bioeconomy were employed to first assign ranks to biomass supply chain items by cost intensity. Then, a layer of analytic hierarchical process (AHP) was used to weigh and rank various biomass supply pathways by efficiency. The results reveal that biomass extraction ranks the highest and biomass feedstock storage ranks the lowest, relative to other supply chain costs. Extracting and chipping material in the field attracted the most support from the experts in terms of efficiency, followed by transporting and chipping at the roadside and, finally, transporting and chipping at the conversion plant. This study provides insights for designers of the forest-based bioeconomy in Australia into relative cost drivers that may be applied to investment and industry decisions. It also provides a framework to support further investigations into forest biomass development and the management of biomass as a renewable carbon carrier at a time when Australia is transitioning from an energy policy focused on fossil fuels to a renewable energy strategy.

Enhanced total nitrogen removal and membrane fouling control by increasing biomass in MBR equipped with ceramic membrane

Simultaneous nitrification and denitrification (SND) is an efficient method to remove nitrogen in municipal wastewater treatment. However, low dissolved oxygen (DO) concentrations are generally required, leading to serious membrane fouling in membrane bioreactors (MBRs). This study aimed to clarify the synergistic effect of biomass and DO on nitrogen removal and membrane fouling. To achieve this goal, four submerged MBRs equipped with ceramic membranes were operated with different biomass (mixed liquor suspended solids (MLSS)) concentrations (3 000 mg/L, 5 000 mg/L, 7 500 mg/L, and 12 000 mg/L) under various DO concentrations (2.0 mg/L, 1.0 mg/L, and 0.5 mg/L). As a result, increasing biomass in the MBRs enhanced total nitrogen (TN) removal via SND, and excellent TN removal efficiencies of 60.7% and 75.8% were obtained using the MBR with an MLSS concentration of 12 000 mg/L and DO concentrations of 2.0 mg/L and 1.0 mg/L. However, a further decrease in DO deteriorated TN removal due to the inhibition of nitrification. Moreover, high MLSS concentrations were beneficial to membrane fouling control for ceramic membranes in MBRs. The lowest transmembrane pressure development rate was observed for the MBR with an MLSS concentration of 12 000 mg/L. High biomass offset the adverse effect of DO decrease on membrane fouling to some extent, and improved the stability of the reactor. Therefore, biomass might be an important parameter for membrane fouling reduction in ceramic MBRs. Overall, optimal biomass and DO concentrations for TN removal were identified, providing useful information for the successful operation of MBRs with efficient TN removal and membrane fouling control.

Application of Artificial Neural Network (ANN) as a predictive tool for the removal of pharmaceutical from wastewater streams using biochar: a multifunctional technology for environment sustainability

This study investigates biochar as an attractive option for removing pharmaceuticals from wastewater streams utilizing data from various literature sources and also explores the sensitivity of the characteristics and implementation of biochar. ANN 1 was designed to determine the optimal biochar characteristics (Surface Area, Pore Volume) to achieve the maximum percentage removal of pharmaceuticals in wastewater streams. ANN 2 was developed to identify the optimal biomass feedstock composition, pyrolysis conditions (temperature and time), and chemical activation (acid or base) to produce the optimal biochar from ANN 1. ANN 3 was developed to investigate the effectiveness of the biochar produced in ANN 1 and 2 in removing dye from water. Biomass feedstock with a high lignin content and high volatile matter at a high pyrolysis temperature, whether using an acid or base, achieves a high mesopore volume and high surface area. The biochar with the highest surface area and mesopore volume achieved the highest removal percentage. Regardless of hydrophobicity conditions, at low dosages (0.2), a high surface area and pore volume are required for a high percent removal. And with a higher dosage, a lower surface area and pore volume is necessary to achieve a high percent removal.

The more, the better? Effect of density on the growth of the lesser mealworm, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae)

Abstract Understanding the concept of larval density scaling in mealworm farming enables us to analyze and compare the growth patterns of these species and their overall productivity in terms of produced insect biomass. This paper explores the impact of larval density on the development of the lesser mealworm, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae). Seven different larval densities were examined in laboratory trials, ranging from 7.5 to 53 larvae per cm2, while the volumetric density per vial was consistent through the experiment at 10 larvae per cm3. The results showed a significant effect of larval density, restricted though to specific developmental traits of A. diaperinus larvae. Based on the results, the highest overall yield and biomass production was achieved at 53 larvae per cm2, however, this density resulted in prolonged development time and decreased larval growth and feed consumption metrics. It is suggested that a larval density of 30.3 larvae per cm2 could offer a favorable balance for achieving optimal biomass efficiency in terms of the time required for harvest, growth performance, feed utilization and economic feasibility. Nevertheless, to the best of our knowledge, this is the first work on the effect of larval density on the performance of A. diaperinus larvae and aims to contribute to the increase of the profitability of A. diaperinus mass-rearing production systems.

Development and Economic Analysis of Bioethanol Production from Palm (Arenga Pinatta) Biomass with Ionic Liquid Pretreatment Using SuperPro Designer Software

Bioethanol has many functions both as a chemical, food and as a source of energy. The development of bioethanol production is currently leading to the residue of the main product. So that in this study the biomass of arena or Arenga Pinatta was used with a large availability of waste. Therefore, a performance and economic analysis was carried out in the production of bioethanol from palm biomass with ionic liquid (IL) using SuperPro Designer (SPD) Software. As a preparatory stage, the process of testing the characteristics of the biomass is carried out to obtain the most optimal composition of palm sugar in bioethanol production. After simulating the conditions according to the experimental process on the most optimal palm biomass composition, it was found that the most optimal Ionic Liquid (IL) and biomass ratio was at 0.5 g/g with the ethanol concentration obtained at 90.6 g/L at 13 hours which corresponds to theoretical yield of 96% conversion of biomass to ethanol. Meanwhile, the production of ethanol in a factory for energy can minimize the price of ethanol by 30% from the initial price. Thus, with the abundant availability of biomass, bioethanol production with aren biomass has the potential to be developed in Indonesia

Effect of feeding a combination of silage of fish offal and fermented tofu dregs with different doses on the population and biomass of silkworms (Tubifex tubifex)

Silkworm (Tubifex tubifex) is one of the natural food that is often used in fish farming. Determining the success of silkworm cultivation is strongly influenced by the culture media, which is generally rice mud. Rice field mud is a living medium for silk worms in nature, but the low nutrient content requires the addition of silage of fish offal and fermentation of tofu dregs. This study used a maintenance medium dose of 100% rice field mud (control), 75% fish offal silage + 25% tofu dregs fermentation (P1), 50% fish offal silage + 50% tofu dregs fermentation (P2), and 25% of tofu silage. fish + 75% tofu dregs fermentation (P3). The main parameters in this study were the growth of biomass and population of silkworms during 21 days of rearing. While the supporting parameters of this research are water quality parameters which include temperature, pH, and DO. Analysis of the data in this study using Analysis of Variance (ANOVA) 1 factors. The results of the calculation of optimal biomass and population were obtained in 25% silage of fish offal + 75% fermented tofu dregs with an absolute biomass value of 18.6 grams and an absolute population value of 8,698 individuals.

Mechanism of supercritical water gasification of corn stover for hydrogen-rich syngas: Composition of reaction products

Hydrogen-rich syngas from supercritical water gasification (SCWG) of renewable biomass is a promising technology. However, due to the complexity of the biomass structure, there is limited research on the liquid and solid products generated by SCWG of real biomass, and the related hydrolysis and gasification mechanisms are not yet clear. In this study, SCWG experiments were carried out on corn stover through a batch reactor, and the products were analyzed by gas-phase GC, liquid-phase GC-MS, UV spectroscopy, ultimate analysis, FTIR, PY-GC/MS, BET specific surface area, and SEM. The mechanism of corn stover SCWG was revealed by qualitative and quantitative analyses of gas products, the composition of liquid products, and the functional groups, carbon skeleton, surface morphology and specific surface area of solid products. The results showed that the aliphatic groups were hydrolyzed and gasified first at 400–500 °C. When the temperature rose to 600 °C, the aromatic groups were also gradually hydrolyzed and gasified, and the remaining aromatic groups underwent condensation and dehydrogenation to produce large molecular naphthalene, phenanthrene, pyrene, etc. The optimal biomass concentration was between 10.5 and 1 g/100 g water during the corn stover SCWG, and the reaction was completed in 15 min.