Optimal Conditions For Production Research Articles

Kinshasa Province (Democratic Republic of Congo): Typology of Peri-Urban Ecosystems Providing Edible Insects

Tropical peri-urban ecosystems are essential for the urban population’s well-being through the goods and services they provide. Unfortunately, these ecosystems are subjected to anthropogenic pressures for various reasons. This study aims to assess the diversity and structure of the peri-urban ecosystems that provide the most edible insects in Kinshasa. A total of 360 people were interviewed to identify the two insect species most frequently consumed. The tree inventory was carried out in 50 plots (2500 m2 each), of which 25 were in Acacia plantations, 10 were planted Milletia forests, and 15 were natural Millettia forests. The diameters of each tree, dbh ≥ 10 cm, were measured. Principal component analysis (PCA) was used to distinguish the forest communities. Diversity indices were used to assess floristic variability and structural parameters were used to characterize forest stands. Two insects were identified as being the most commonly consumed in Kinshasa: Gonimbrasia jamesoni (28%) and Cirina forda (27%), found the in Acacia plantation, and in the planted Milletia forests and natural Milletti forest, respectively. The results indicate floristic (higher in the Acacia plantation) and structural variability between stands. The structure of the stands indicates good news for all forests, except the planted forest. The high frequency/dominance of A. auriculiformis and M. laurentii in the peri-urban ecosystems of Kinshasa would therefore be optimal conditions (under natural conditions) for good production of these two caterpillar species.

Prediction of glass phase viscosity in firing traditional ceramics and porcelain tiles with waste glass powder

The theoretical calculation of the viscosity of traditional ceramic materials is complex and models based on glass processing are generally used to estimate the viscosity of the glass phase according to its chemical composition. FactSage model considers structural information from silicate melts (glass phase), which is a different approach compared to other models. The viscosity of the melt fraction was calculated for different traditional ceramics, such as hard porcelain, technical porcelain, sanitary ware and porcelain tiles, including formulations with partial replacement of the fluxing raw material by soda-lime glass waste. FactSage model consistently indicated an increase in viscosity with higher levels of silica and a decrease in viscosity with the utilization of soda-lime glass waste in the formulations. Different responses and a nonlinear behavior were presented when varying the Na2O/K2O contents in the glass phase. The tested models presented reliable results for the processing of molten glass, but depending on the chemical composition and temperature, significant differences were observed among the values. Despite this, models that simulate the viscosity of the glass phase can help to optimize production conditions, but more investigations are needed to improve the relationship between theoretical and experimental results of viscosity.

Isolation and characterization of probiotic bacteria from fruit pulp, screening of probiotic properties and production of bacteriocin and probiotic curd

The present study was investigated to isolate probiotic lactic acid bacteria from Actinidia deliciosa (kiwi fruit) pulp. A total of eight isolates were found and two of them were probiotic LAB strains. The both A2 and A5 isolates strains were Gram-positive, catalase and oxidase negative, non-spore forming, non-motile, rod or short cocci shaped bacteria. The A2 and A5 strains both survived well in conditions of low pH, 0.4% phenol and high bile salt concentrations. They could grow at different temperatures and were resistant to different NaCl concentrations. A study was also conducted on the various probiotic and safety attributes of isolates. Bacteriocins, a kind of ribosomal protein produced by LAB, were estimated using the Folin-Lowery method. The formation of bacteriocins was influenced by various physical and chemical factors. The result demonstrates that the optimum conditions for the production of bacteriocins by the A2 strain were glucose as carbon source, pH 6.5, 2% NaCl and 1% bile salts. For the A5 strain, sucrose as a carbon source, pH 6.5, 1% NaCl and 1% bile salt were optimum conditions for bacteriocin production. Study was also conducted on exopolysaccharide (EPS) production, adhesion characteristics, antagonistic activity and antibiotic sensitivity. Probiotic curd (Dahi) formation was done and several parameters of curd like pH, total lactic acid concentration and water-holding capacity were all investigated.

Yield and Technological Quality of Pirarucu Trimming Surimi According to the Number of Washing Cycles, Rice Flour Content, and Cooking Temperature.

This research aimed to optimize surimi production with innovative raw materials called pirarucu trimmings and broken rice grains, which are by-products from food industries. The effects of three independent variables (number of washing cycles, content, and cooking temperature of rice flour-RF) on surimi's physical, chemical, and technological qualities were investigated through a Box-Behnken design. The number of washing cycles affected yield (77-93%), moisture (55-67%), lipids (18-35%), protein (7.15-11.88%), whiteness (46.73-64.45), chroma (8.86-13.18), hue angle (80.79-93.12°), cohesiveness (0.40-0.61), springiness (0.51-0.99), and freeze stability after 4 weeks (85.16-96.53%). RF concentration affected moisture, lipids, cohesiveness, springiness, and freeze-thaw stability after 4 weeks. RF cooking temperature affected moisture, chroma, cohesiveness, and springiness. The optimal conditions for surimi production with high yield and overall quality were three washing cycles, 6% of RF, and RF cooking temperature at 85 °C. It reveals the promising potential of both by-products to be used as an ingredient in restructured products and contribute to improving agri-industry sustainability.

Effect of different carbon sources on exopolysaccharide production of Lactiplantibacillus pentosus KS27 and optimization of production conditions using Box-Behnken designing

Effect of different carbon sources on exopolysaccharide production of Lactiplantibacillus pentosus KS27 and optimization of production conditions using Box-Behnken designing

Study on the mechanical strength and iodine adsorption behavior of coal-based activated carbon based on orthogonal experiments

To prepare coal-based activated carbon with high mechanical strength and adsorption performance for the removal of iodine from wastewater, the effects of carbonization temperature, heating rate, activation time and activator on the mechanical strength of activated carbon were studied; the optimal production conditions were determined by comprehensively considering the specific surface area, iodine value, compressive strength and wear resistance based on previous studies. Iodine adsorption kinetics and equilibrium adsorption experiments were carried out on activated carbon prepared under the optimum conditions. The results showed that the increase in mechanical strength was caused by the release of volatile matter and secondary reactions, which formed the carbon skeleton, while the decrease in mechanical strength was due to the intervention of the activator, which destroyed the carbon skeleton. The adsorption kinetics showed that a pseudo-second order kinetic model was more suitable for the adsorption behavior of iodine on activated carbon. The equilibrium adsorption experiment results showed that iodine was evenly adsorbed on the surface of activated carbon, and with increasing temperature, the affinity of the active sites of activated carbon to iodine also increased.

Optimization Condition for Ethanol Production from Sweet Sorghum Juice by Recombinant Zymomonas mobilis Overexpressing groESL Genes

High-temperature ethanol fermentation (HTEF) using high-potential thermotolerant ethanologenic microorganisms is a promising platform for ethanol production in tropical or subtropical areas. This study aims to evaluate the ethanol production potential of recombinant Zymomonas mobilis R301 overexpressing groESL genes under normal and high-temperature conditions and the expression of genes involved in the heat shock response and ethanol production pathway during ethanol fermentation using sweet sorghum juice (SSJ) as feedstock. Growth characterization analysis revealed that the recombinant Z. mobilis R301 exhibited multi-stress tolerance toward heat, acetic acid, and furfural. Based on the statistical experimental design, the optimum conditions for ethanol production from SSJ by the recombinant R301 at 30 °C were a sugar concentration of 171.67 g/L, cell concentration of 9.42% (v/v), and yeast extract concentration of 10.89 g/L, while those at 40 °C were a sugar concentration of 199.48 g/L, yeast extract concentration of 10.88 g/L, MgSO4 concentration of 1.05 g/L, and initial pH of 6.8. The maximum ethanol concentrations and productivities achieved in this study were 63.26 g/L and 1.17 g/L.h at 30 °C and 58.62 g/L and 1.22 g/L.h at 40 °C. The overexpression of the groES and groEL genes and upregulation of other heat shock-responsive genes at 40 °C enhanced cell growth, viability, and fermentation capacity of recombinant Z. mobilis R301 under heat stress. The current study demonstrated that recombinant Z. mobilis R301 exhibited high potential for ethanol production from SSJ or other sugar-based raw materials under high-temperature conditions.

Box–Behnken optimization of biodiesel production using trisodium phosphate catalyst from monazite ore processes

AbstractTrisodium phosphate (TSP) is a non‐toxic waste obtained from alkaline cracking as part of the processing of monazite ore. After simple purification, TSP can be utilized in many applications; however, it is used as a catalyst in this study. It is characterized using Thermogravimetric analysis , X‐ray diffraction analysis, Brunauer‐Emmett‐Teller, and Temperature‐programmed desorption of carbon dioxide and optimized in the transesterification reaction. After recrystallization and calcination at 350 °C for 0.5 h, the form of the TSP was tetragonal, with a 2.61 m2/g surface area and 537.4 x 10‐6 mol/g basic sites. Trisodium phosphate can therefore be utilized effectively as a solid base catalyst for the transesterification of palm oil. Three biodiesel production parameters were investigated: the methanol to oil molar ratio (6:1–24:1), catalyst concentration (1–10%), and reaction time (30 to 240 min). The experiments were designed using the Box–Behnken response surface method. As a result, the optimum conditions for biodiesel production are a 22:1 methanol to oil molar ratio, 4% catalyst concentration, and 200 min reaction time. The optimal fatty acid methyl ester (FAME) content is 99.79%, with an error between actual and predicted FAME of 0.21%. © 2023 Society of Industrial Chemistry and John Wiley & Sons Ltd.

Determination the Optimum Conditions for β-glucan Production Extracted from Saccharomyces cerevisiae

Β-glucan is a natural polysaccharide composed of a group of glucose monomers linked by beta glycoside bonds that yeasts can be synthesized. The effect of different temperatures, inoculum size, glucose concentration, yeast extract concentration, pH, and culture media on the β-glucan production from saccharomyces cerevisiae was studied. In addition, the dry weight of biomass containing β-glucan was measured. The results showed that the optimum conditions for β-glucan production were when the cells were grown at 30 ºc for 48 hours and pH = 7 with 10 % inoculum size, 2% glucose, and 0.1% yeast extract. Furthermore, the best culture medium for β-glucan production was yeast extract-glucose medium with a dry weight of glucan 2.5mg/5ml. In addition, this study aimed to determine the best method for β-glucan extraction with acceptable purity and concentration. Β-glucan was extracted using two methods autolysis and alkali-acids extraction. The dried and weighed crude β-glucan was 6 gm/l, and 8 gm/l for autolysis of yeast cells, and alkali-acids extraction, respectively. The analysis of glucan by FT-IR and HPLC showed that the method of extraction by autolysis of yeast cells was successful to obtain β-glucan without the presence of the α-glucan with a concentration of β-glucan 10.8mg/gm, while in the extraction by alkali-acid were obtained mixtures of α-glucan and β-glucan with the concentration of β-glucan 7.4 mg/gm. The current study revealed that the optimum conditions of β-glucan production and the best culture medium for β-glucan production was yeast extract-glucose medium and the best method for β-glucan extraction was autolysis extraction.

Screening, Identification, and Optimization of Enzyme-Producing Conditions for Cellulose-Degrading Bacteria in Distillery Lees

Cellulose-degrading bacteria were identified from distillery lees, and the strains were optimized for fermentation and enzyme production, providing effective strains for the resource utilization of distillery lees and developing cellulase. Based on the univariate test, the response surface test was used to optimize enzyme production conditions for fermentation. The screened strain JZ2 had a clear circle-to-colony diameter ratio of 2.0. The enzyme activities of exoglucanase, endoglucanase, and β-glucosidase were 4.341 ± 0.05 U/mL, 1.874 ± 0.04 U/mL, and 0.739 ± 0.02 U/mL, respectively. The bacterial colonies were large, and the bacterial cells’ morphology was rod-shaped. We identified Bacillus cereus (JZ2) from 16S rDNA sequence homology and phylogenetic tree analysis as belonging to the genus Bacillus in the thick-walled Bacillus phylum. The optimum production conditions of cellulase from strain JZ2 were a fermentation time of 2 d, a rotation rate of 180× g, and a temperature of 26 °C using the response surface method. The enzyme activity of JZ2 was 4.625 U/mL under optimal enzyme production conditions. In addition to good activity, the cellulase from the JZ2 strain may have the potential to convert distillery lees cellulose into useful compounds.

Toxicity of Bikaverin to Some Pathogens and Optimal Production Conditions

Bikaverin is a reddish pigment produced by a variety of fungal species, the majority of which belong to the Fusarium genus. This pigment has antibiotic activities against protozoa, bacteria, and fungus. This study looked at the toxicity of Bikaverin to some microbes, production, and characterization of the pigment from the fungus Fusarium oxysporum. The yield of total bikaverin in F. oxysporum shake flask culture was improved by optimizing cultivation variables such as complex medium, carbon supply, nitrogen source, temperature, medium pH, and incubation period. The maximum production of complete bikaverin was found after 10 days at 28°C in Potato dextrose broth [PDB] supplemented with 2% glucose, 2% corn step liquor, and a pH of 5.5. The isolates of more sensitive bacteria to bikaverin were Staphylococcus aureus and S. typhi, with inhibition zones 24 and 23 mm respectively, at a concentration of 75 ?g/mL. The isolates more sensitive fungi to bikaverin were E.faecalis, E. coli, C. albicans, and P. aeruginosa, with inhibition zones 18, 22, 20 and 13 mm, respectively, at concentrations of 75 ?g/mL. The study concluded that the toxic antimicrobial activity of bikaverin was against fungi and bacteria

Microalgae Cultivation Using Municipal Wastewater and Anaerobic Membrane Effluent: Lipid Production and Nutrient Removal

Microalgae cultivation using wastewater is a combined process for pollutant removal and lipid production that has been widely studied in recent years. In this study, the effects of anaerobic membrane effluent (AME) and municipal wastewater (MW) ratios on microalgae growth and pollutant removal processes were investigated, and the lipid production properties were also explored. Results show that microalgae can grow in all AME/WW ratios, and a 40% AME content is the optimal condition for microalgal biomass accumulation (52.9 mg/L·d) and lipid production (0.378 g/L). Higher AME addition would inhibit microalgae growth. In addition, high ammonia (approximately 97%) and phosphate (around 90%) removal efficiencies can be achieved in all AME/WW ratio conditions, while the total nitrogen removal efficiencies decreased with the addition of AME. Total nitrogen and phosphate are the limiting factors in treating water to meet the requirements of the integrated wastewater discharge standard. This study provided a new method for anaerobic digestion and municipal wastewater treatment and also realized green energy production based on the sustainable development principles.

Production of ethyl esters using municipal sewage sludge and porous ionic liquid coordinated with Burkholderia lipase

Lipase from Burkholderia species immobilized onto novel mesoporous polymeric ionic liquids (MO(Poly)Cn–BLE) could be utilized as a low–cost biocatalyst for the lipase-catalyzed synthesis of free fatty acid esters from dried municipal sewage sludge. To assess this, this investigation has focused on three main parts of this process: (i) the development of a series of large surface polymer synthesis; (ii) mesoporous polymeric biocatalyst preparation using lipase from Burkholderia sp. immobilization onto MO(Poly)Cn, and supports for this alongside Mesoporous polymer ionic liquid–1–bromooctane–lipase from Burkholderia sp. enzyme (MO(Poly)C18–BLE) were characterized using FT-IR, SEM, XPS, N2, and TGA; (iii) Response surface methodology was used to determine the optimal conditions for ester production from municipal sewage sludge lipids using a central composite design. Four process variables were assessed at three levels; a total of 13 experiments were performed to study the effects of the lipids: ethanol molar ratio, catalyst concentration, reaction time, and temperature on the ester’s yield. A 91.25% ester yield was obtained under optimal conditions: a 1:12 molar ratio of municipal sewage sludge lipid to ethanol, 225 wt% MO(Poly)C18–BLE, 5 h reaction time, 45 ℃ reaction temperature, and a constant 150 rpm agitation. This novel biocatalyst synthesis method and ester production process from municipal sewage sludge lipids may provide ecological and economic support for industrial biodiesel production in the future.

Optimization of carotenoid production by Umbelopsis ramanniana.

Umbelopsis ramanniana was investigated to increase carotenoid production. Nine different carbon sources and six different nitrogen sources were evaluated for the maximum carotenoid production. The most effective nitrogen and carbon sources were KNO3 and lactose, respectively. Then, the optimization of medium components for enhancement of carotenoid production by Umbelopsis ramanniana was achieved using Plackett-Burman design. Box-Behnken response surface methodology was applied to further optimize carotenoid and biomass production. Carbon to nitrogen ratio, lactose concentration, and shaking speed were studied as variables in Box-Behnken design. The optimum conditions for carotenoid and biomass production were determined as 32.42 g/L of lactose concentration, 20:1 of carbon to nitrogen ratio, and shaking speed of 130 rpm. The maximum carotenoid and biomass production under optimized conditions were 1141 μg/L (β-carotene-Eq) and 13.14 g/L, respectively. When compared to the control fermentation, carotenoid, and biomass production were increased by about 2 and 1.3 folds, respectively.

Ion Exchange Resin and Entrapped Candida rugosa Lipase for Biodiesel Synthesis in the Recirculating Packed-Bed Reactor: A Performance Comparison of Heterogeneous Catalysts

Ion exchange resins and immobilized lipase as heterogeneous catalysts are used to synthesize biodiesel for alternative fossil fuels. The use of ion exchange resins in the solid and activated phase can ease the separation process. Furthermore, resins can be reactivated and used repeatedly, reducing the need for catalysts. On the other hand, an immobilized enzyme is biodegradable and can catalyze the transesterification process to produce biodiesel with a lower alcohol-to-oil ratio, minimizing side reactions and impurities. Therefore, the catalysts used in this study are ion exchange resins, such as Lewatit MP-64, Amberlite IRA410Cl, and Diaion PK208LH, as well as immobilized Candida rugosa lipase. By using vegetable oil as a feedstock and methanol for the transesterification, biodiesel production was carried out in a packed bed reactor. The present study aims to investigate the optimum process parameters, including the concentration of resin and enzyme, resin activation time, resin types, flowrate, and stability of resin and enzyme on the biodiesel yield. The results showed that the optimum conditions for biodiesel production with ion exchange resin were 4 g of resin, activated for 3 h, and synthesized for 3 h; Lewatit obtained a biodiesel yield of 94.06%, Amberlite obtained 90.00%, and Diaion obtained 73.88%. Additionally, the stability test of the reactivated Lewatit resin showed that it still has the capability of producing biodiesel with a yield of more than 80% after three regeneration cycles. In contrast, Candida rugosa lipase as was immobilized by entrapment in sodium alginate before being used in the biodiesel production for 12 h. The results showed that lower flowrate in enzymatic biodiesel synthesis produced a higher amount of biodiesel, of up to 71.1%. Nonetheless, immobilized lipases can be used up to three times without a significant loss in biodiesel yield.

Prodigiosin-Producing Serratia marcescens as the Causal Agent of a Red Colour Defect in a Blue Cheese.

Technological defects in the organoleptic characteristics of cheese (odour, colour, texture, and flavour) reduce quality and consumer acceptance. A red colour defect in Cabrales cheese (a traditional, blue-veined, Spanish cheese made from raw milk) occurs infrequently but can have a notable economic impact on family-owned, artisanal cheesemaking businesses. This work reports the culture-based determination of Serratia marcescens as the microbe involved in the appearance of red spots on the surface and nearby inner areas of such cheese. Sequencing and analysis of the genome of one S. marcescens isolate, RO1, revealed a cluster of 16 genes involved in the production of prodigiosin, a tripyrrole red pigment. HPLC analysis confirmed the presence of prodigiosin in methanol extracts of S. marcescens RO1 cultures. The same was also observed in extracts from red areas of affected cheeses. The strain showed low survival rates under acidic conditions but was not affected by concentrations of up to 5% NaCl (the usual value for blue cheese). The optimal conditions for prodigiosin production by S. marscescens RO1 on agar plates were 32 °C and aerobic conditions. Prodigiosin has been reported to possess antimicrobial activity, which agrees with the here-observed inhibitory effect of RO1 supernatants on different bacteria, the inhibition of Enterobacteriaceae, and the delayed development of Penicillium roqueforti during cheesemaking. The association between S. marcescens and the red colour defect was strengthened by recreating the fault in experimental cheeses inoculated with RO1. The data gathered in this study point towards the starting milk as the origin of this bacterium in cheese. These findings should help in the development of strategies that minimize the incidence of pigmenting S. marcescens in milk, the red defect the bacterium causes in cheese, and its associated economic losses.

DEVELOPMENT OF ENTEROBACTER CLOACAE IP8 MUTANT STRAIN PRODUCING THERMOSTABLE CELLULASE

Mutagenesis of Enterobacter cloacae IP8 for enhanced cellulase production was carried out using ultraviolet (UV) irradiation and ethyl methanesulphonate (EMS) treatment. The mutant strain exhibited cellulolytic activity which was 2.18-fold higher than that of the wildtype strain. The optimal conditions for cellulase production were an incubation period of 28 h, a temperature of 45 oC, and pH 7.0, using CMC and peptone as carbon and nitrogen sources, respectively. The cellulases from both strains were purified by using ammonium sulfate precipitation, CM Sephadex C-50, and Biogel P-100 column chromatography. The specific activity of the purified cellulase from the mutant strain was 29.47 U/mg while that of wildtype cellulase was 21.5 U/mg. Biochemical characterization of the purified enzyme revealed the optimum pH and temperature of 8.0 and 65 oC, respectively, for the cellulase from the mutant strain, and 7.0 and 60 oC for the wild-type cellulase. The mutant cellulase was thermally stable up to 70 oC retaining 86.5% of its original activity after 180 h. Metal ions Na+ and Ca2+ remarkably enhanced the activity of the cellulase from both strains while Al3+ and the chelating agent, EDTA, strongly inhibited the activity. Mutagenesis of E. cloacae IP8 using combined UV and EMS treatment led to the development of mutant strain with enhanced capacity for the production of cellulase exhibiting novel properties such as thermostability, alkalinity, low Km, and high Vmax values. Therefore, the enzyme from the mutant strain of E. cloacae IP8 has the potential for broad industrial applications.

ANTIMICROBIAL PIGMENT FROM FUSARIUM GRAMINEARUM: OPTIMIZING CONDITIONS AND UTILIZING AGRO-INDUSTRIAL RESIDUES

Fusarium sp. produces various bioactive pigments widely used in pharmaceuticals, cosmetics, and the food industry. This study investigated the antimicrobial effect of the pigment produced from the highest pigment-producing Fusarium sp. strain and determined the optimum growth conditions and agro-industrial residues to obtain maximum pigment production. Fusarium equiseti, Fusarium graminearum, and Fusarium poae strains were tested in terms of their pigment production levels. Pigment quantification was assessed by a UV–Visible Spectrophotometer at 500 nm. Antimicrobial tests were determined by Disc Diffusion and Well Diffusion Methods. According to our results, the highest amount of pigment-producing strain was F. graminearum (p<0.001) and malt extract broth (MEB) was the optimum growth media (p<0.001). Extracted F. graminearum pigment was antimicrobial against B. cereus and S. aureus with a zone of inhibition diameters of 10.2 and 14.9 mm respectively. Initial pH levels of 8, 150 rpm rotation speed, 30 ºC temperature, and 9 days of incubation under the light condition in MEB media were determined as the optimum growth conditions for the highest reddish pigment production. Moreover, 10-2 times diluted molasses, Turkish feta cheese whey, and Turkish cheddar cheese whey were found as suitable low-cost growth media for reddish pigment production by F. graminearum. Our findings not only represent a pigment that might be used in the food industry as an antimicrobial bio-colorant but also show the potential use of molasses and whey as low-cost growth media for reddish pigment production by F. graminearum.

Enhanced low-temperature production of biodiesel from waste cooking oil: aluminum industrial waste as a precursor of efficient CaO/Al2O3 nano-catalyst

The objective of the current study is to employ aluminum industrial waste (AIW) as a precursor for the preparation of a novel environmentally benign CaO/Al2O3 nano-catalyst for efficient biodiesel production from waste cooking oil (WCO) at a low optimizing reaction temperature. Physico-chemical characterizations of the as-prepared CaO/Al2O3 nano-catalysts are performed under various conditions via diverse analytical techniques such as TGA, XRD, XPS, BET, SEM - EDX, TEM, and AFM. The calcination temperature influence along with the ratio of CaO to Al2O3 on the catalyst activity toward biodiesel conversion have been investigated and optimized. Furthermore, the optimization process of the four variable parameters of the transesterification reaction (i.e., catalyst loading, reaction temperature and time, and M:O molar ratio) are investigated. The optimum reaction conditions for biodiesel production (≈ 95% conversion) are catalyst loading of 3 wt.% operating at 45 °C for 180 min with a methanol to oil ratio of 7:1. These conditions are superior to comparable catalysts reported in the literature. The kinetic and thermodynamic parameter's values, i.e., activation energy (Ea), activation enthalpy (ΔH#), and activation entropy (ΔS#) are 39 kJ mol−1, +36.38 kJ mol−1, and ─161.75 J mol−1 K−1, respectively. The as-prepared nano-catalyst retains its catalytic activity for five consecutive cycles. Physico-chemical characteristics of the produced biodiesel are congruent with the ASTM D − 6751 and EN − 14,214 standards. Therefore, it may be thought of as a potential catalyst for renewable producers of biodiesel production.

Accuracy assessment of RFerns, NB, SVM, and kNN machine learning classifiers in aquaculture

BackgroundFish diseases are the primary cause of decreased productivity and financial losses in fish farms. Detecting and monitoring fish disease using human eye is a time-consuming manual process. Technological advancements have made possible that data may now be collected at unprecedented speeds, quantities, and complexity, with far less effort and expense. Species must be provided optimum environmental conditions for healthy production. However, sub-optimal conditions and managerial issues could lead to disease outbreaks in fish farms. Machine learning (ML) classifiers can provide solutions to fish farm difficulties by collecting data with less efforts. MethodsThis study investigated water physico-chemical parameters potentially responsible for bacterial disease outbreak in fish farms. Four most popular ML algorithms, i.e., support vector machine (SVM), naïve bayes (NB), random ferns (RFerns), and K-nearest neighbor (kNN) were used to detect the physico-chemical parameters of water causing the disease. Data were collected from 3 different farms in two-month periods for 1 year. Models were developed by using 10-fold cross validation procedure to the training dataset data for each model. The models were examined using seven distinct metrics throughout the training and testing phases. ResultsThe SVM and RFerns classifiers produced accurate results (100% for both) during the testing phase, while kNN and NB classifiers achieved lower accuracy (91.3% accuracy for both). ConclusionThe SVM and RFerns algorithms performed better than kNN and NB algorithms in both the training and testing phases of the study. Although earlier research confirms the efficacy of the SVM algorithm in aquaculture, comparable efficacy of RFerns with SVM has been reported in this sector for the first time, which is a significant addition to the literature.