Optimal Conditions For Production Research Articles

Production, characterization and application of polygalacturonase produced by Lentinus tigrinus CCMB 553

Polygalacturonases can be used to improve the processing of fruit juices and wines. This study aimed to produce, characterize and evaluate the potential application of polygalacturonase obtained from Lentinus tigrinus CCMB 553 in mango juice clarification. The fungal was isolated from the northeastern semi-arid region and fermented using Passiflora cincinnata bark as a substrate for solid state fermentation. The optimal conditions for enzyme production were obtained by applying the three-level factorial experimental design and were defined as 9 days and 30 °C for time and temperature, respectively. The optimal pH and temperature were determined by applying the Doehlert design and the results showed higher production between 45 and 60 °C and 4.0 and 5.5 for temperature and pH respectively. Km and Vmax of polygalacturonase from Lentinus tigrinus were 2.7 mg/mL and 12.86 μmol/min. The enzyme maintained 40 % residual activity after 30 min at 80 C. The influence of cations on enzyme activity was studied, and calcium ions seem to have a positive influence on enzyme activity, while Fe2+ ions have a negative influence. K+, Na+ and NH4+ salts showed little influence on the polygalacturonase activity of Lentinus tigrinus. The application in the clarification of mango juice (Mangifera indica) using optimal conditions obtained resulted in a reduction of 45% of the viscosity and the clarification by about 79%. The results show that the polygalacturonase produced by Lentinus tigrinus CCMB 553 was efficiently applied in mango juice, improving the quality of the juice.

Production and quality evaluation of a novel γ-aminobutyric acid-enriched yogurt.

γ-aminobutyric acid (GABA) is a neurotransmitter inhibitor that has beneficial effects on various health conditions such as hypertension, cognitive dysfunction, and anxiety. In this study, we investigated a novel yogurt naturally enriched with GABA using a Levilactobacillus brevis strain isolated in our laboratory; the specific optimum yogurt production conditions for this strain were determined. We isolated an L. brevis strain and used it to produce yogurt naturally enriched with GABA. We explored the optimal conditions to enhance GABA yield, including fermentation temperature, inoculation amount, L-monosodium glutamate (L-MSG) concentration, fermentation time, and sucrose content. We also performed mixed fermentation with Streptococcus thermophilus and evaluated the quality of the yogurt. Following optimization (43°C, 8% inoculation amount, 1.5 g/L L-MSG, and 8% sucrose for 40 h of fermentation), the GABA yield of the yogurt increased by 2.2 times, reaching 75.3 mg/100 g. Mixed fermentation with S. thermophilus demonstrated favorable results, achieving a GABA yield akin to that found in some commercially available functional foods. Moreover, the viable microbe count in the GABA-enriched yogurt exceeded 1 × 108 cfu/mL, which is higher than that of commercial standards. The yogurt also exhibited a suitable water-holding capacity, viscosity, 3-week storage time, and favorable sensory test results. This study highlights the potential of naturally enriched GABA yogurt as a competitive commercial yogurt with beneficial health effects.

Preparation and characterization of composite-modified PA6 fiber for spectral heating and heat storage applications

Abstract Composite coating technology was used to prepare a modified polyamide 6 (PA6) polymer material masterbatch with low mutual interference and good spinnability using molybdenum oxide, tungsten trioxide, graphene oxide, etc., as modifiers. Experiment shows that using nanoscale composite-coated modified masterbatches capable of spectral heating and heat storage in the preparation of nylon 6 fiber, adding modified masterbatches with a mass ratio of 6% online, and controlling various process parameters can result in good functionality and usability as well as enable consistent production. Optimal production conditions are achieved by utilizing pre-dried PA6 chips with a moisture content of 420 ppm. The master batch is subjected to drying at a temperature of 95°C for 12 h. During this process, the master batch is introduced at an addition ratio of 6%. Subsequent spinning is conducted at a speed of 4,300 m·min−1 and a temperature of 255°C. Cooling is facilitated by air set at a temperature of 17°C, flowing at a speed of 0.45 m·min−1. In the production line, one roller operates without heating, while the second roller is maintained at a temperature range of 160°C. The stretching process is performed at a ratio of 1.3. To ensure proper lubrication, an oil rate of 1.3% is applied. These meticulously controlled process parameters collectively contribute to the most favorable production status.

Optimization of Enzymatic Transesterification of Acid Oil for Biodiesel Production Using a Low-Cost Lipase: The Effect of Transesterification Conditions and the Synergy of Lipases with Different Regioselectivity.

This study describes the enzymatic production of second-generation biodiesel using low-quality acid oil as a substrate. Biolipasa-R, a commercially available and low-cost lipase, was employed for enzymatic transesterification. Response surface methodology was applied to optimize the enzymatic transesterification process. The optimal conditions for biodiesel production, which comprised 42% lipase concentration (per weight of oil), 32% water content (per weight of oil), a methanol to oil molar ratio of 3:1, pH 7.0 and reaction temperature 30°C, resulted in the highest fatty acid methyl ester (FAME) content (71.3%). Subsequently, the synergistic effect of two lipases with different regioselectivities under the optimum transesterification conditions was studied, aiming at the enhancement of process efficiency. The transesterification efficiency of immobilized Biolipasa-R was determined and compared to that of Biolipasa-R in its free form. The results revealed a good performance on FAME content (66.5%), while the recycling of immobilized lipase resulted in a decrease in transesterification efficiency after three consecutive uses.

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.

Multiomics study on co-fermentation of chemically enhanced sludge and waste activated sludge to produce volatile fatty acids under different temperatures and pHs

This study examined the effects of different temperatures (37°C and 45°C) and pH (uncontrolled, 8 and 10) on the co-fermentation of FeCl3, anionic polyacrylamide (a-PAM) settling chemical enhanced primary sedimentation (CEPS), and waste activated sludge (WAS) to produce volatile fatty acids (VFAs), which analyzed through characterization, microbial community, and untargeted metabolic pathways. Further, to investigate the interacting effects, temperatures of 37°C, 45°C, and pHs of 8 and 10 were chosen, with a sludge ratio of 7.5. The hydrolysis of sludge was aided by the concentration of soluble chemical oxygen demand (SCOD) rising as temperature and pH rose. Nevertheless, elevated SCOD concentrations failed to materialize into benefits for acid production. Therefore, considering practical applications, the optimal conditions for acid production were determined to be 37°C and pH 10, with a concentration of 3411.17 ± 119.92 mg COD/L. A thorough investigation of correlations between microbial communities, differential metabolites, and environmental factors was carried out, highlighting the significance of pH in relation to microbial and acid production performance. That instance, the pH affects acid generation efficiency more so than temperature parameters. Within the microbial community, there is a considerable positive correlation between several distinct metabolites and Steptococcus, Trichococcus, and Tepidimimicrobium. These metabolites are intimately associated with the materials and energy needed for biological cell production and metabolism. This could be as a result of how environmental influences alter the distribution of microbial populations, which influences various metabolites and ultimately the process of producing acid.

Effectiveness study of recrystallisation method in pharmaceutical salt production from processed salt with zero waste concept

Indonesia's vast archipelago offers abundant seawater resources, holding the potential for salt production. Salt, a vital commodity in human life, typically contains sodium chloride and impurities like Ca2+, Mg2+, SO42−, and K+. Pharmaceutical salt is an industrial category adhering to pharmacopoeial standards regarding sodium chloride levels and impurity content, ensuring quality for drug preparations in Indonesia. Prior research indicates that recrystallisation, specifically evaporation crystallisation, enhances salt quality by increasing NaCl content. Chemical precipitating agents like NaOH and Na2CO3 can be introduced to improve salt purity further. This study aims to identify optimal conditions for pharmaceutical salt production from processed salt raw materials, considering crystallisation time, stirring speed, chemical additives (NaOH and Na2CO3), and double crystallisation stages. The method commences with pre-treatment, involving salt dissolution in distilled water to saturation, with the addition of precipitating agents as per designated variables. Precipitates formed from precipitating agents (NaOH and Na2CO3) are isolated through filtration. The filtrate undergoes evaporation crystallisation at 103 °C, varying between single and double crystallisation. Salt crystals are separated, dried, and weighed to calculate yield. Pharmaceutical salt is analysed for water content, NaCl, and impurities (Ca2+, Mg2+, SO42−, and K+). The optimal conditions for pharmaceutical salt production were double crystallisation with a 20 % excess of chemicals (NaOH and Na2CO3), 100 min of crystallisation time, and a stirring speed of 600 rpm. This yielded a 15 % NaCl content of 99.87 %, Mg2+ at 0 ppm, Ca2+ at 69.6 ppm, SO42− at 366 ppm, K+ at 370 ppm, and water content at 0.166 %. Notably, the pharmaceutical salt production process generates no waste, as byproducts like Mg(OH)2 and CaCO3 can be recycled and hold commercial value. However, it is essential to re-evaluate raw materials and technologies to address the market's high cost and competitiveness issues.

INHIBIION ACTIVITY OF SOME PLANT SEEDS EXTRACTS AGAINST THE PROTEASE PRODUCED FROM LOCAL ISOLATE OF CANDIDA ALBICANS ISOLATE USING SOLID STATE FERMENTATION

This study was aimed at inhibition of purified protease produced by C. albicans using plant seeds extract. One hundred two local C. albicans isolates that were isolated and identified by microscopic and biochemical tests were submitted to primary and secondary screening techniques in order to select the qualified C. albicans isolate for protease synthesis. Among these isolates, nineteen isolates with the highest hydrolysis zone on skim milk media (primary screening) were chosen for secondary screening. It has been found that C. albicansV56 had the highest productivity of the enzyme (41.8U/mg protein). The optimum conditions of protease production by selected isolate using solid state fermentation by using wheat bran as best substrate , temperature 28 °C and pH 7, after 5 days of incubation . The enzyme was purified by concentration with sucrose, then used gel filtration chromatography using Sephadex G-75. The results show two peaks. The first peak has a purification folds 6.5 time with an enzyme yield of 13.08 %, while peak 2 has a purification folds 3.3 time with an enzyme yield of 20%. The purified enzyme exhibited maximal activity at pH 6.0 for peak 1 and 3.0 for peak 2, whereas the maximum stability was 7.0 for peak 1 and 8 for peak 2. The optimal temperature for purified enzyme activity was 40 for peak 1 and 30 for peak 2, and it was stable until 45°C. Protease activity was inhibited with local plant seed extracts. Lathyrus sativus extract inhibits approximately 50 % of protease activity.

The Value of Indigenous <i>Saccharomyces cerevisiae</i> Strains as Useful Enzymes Producers: A Systematic Review

This systematic review has focused on the selection and characterization of indigenous Saccharomyces cerevisiae strains for enzymes' production obtained from the fermentation process. The primary studies assessed have demonstrated that indigenous S. cerevisiae strains produce a wide range of enzymes during fermentation. These strains have shown different characteristics and were isolated from various locations, including those belonging to the main components of the wine production chain. The research methodology applied to find primary studies about the optimal conditions for enzyme production was effective and identified a wide range of enzyme classes. Cultivation media amended with natural or synthetic inducer substrates were found to be suitable carbon and/or nitrogen sources for producing enzymes of interest in plate-based screening. In submerged fermentation studies, the use of agro-industrial residues has been identified as a relevant carbon source for microbe development and metabolism. For the indigenous S. cerevisiae strains, the majority of the enzymes found belong to the glucosidases and hydrolases classes. Due to the activity of these enzymes, yeasts have been traditionally used in classic biotechnological applications, particularly in the process of alcoholic fermentations. Those enzymes are responsible for producing metabolites (such as aromatic compounds) that contribute to the desirable aroma and/or taste during the fermentation of wine, as well as other fermented or distilled beverages. The methods used for enzyme screening were of quantitative and/or qualitative nature and were carried out under acidic pH conditions (3.5-6.5) and at temperatures of 28-35 ℃. The results of this systematic review have shown that the enzymes from indigenous S. cerevisiae are highly relevant in various biotechnological applications, particularly in the food industry. Conclusions and future perspectives of our findings were discussed in terms of potential developments of novel application methods of the indigenous yeasts and their enzymes in agriculture and industry.

Production and Optimization of Extracellular α-amylase From Halophilic Bacteria Cytobacillus oceanisediminis Isolated From Wadi-El-Natrun, Egypt

The current study aimed to maximize α-amylase enzyme production by halophilic bacteria Cytobacillus oceanisediminis isolated from soil of Wadi-El-Natrun, Egypt. The results showed that of 21 halophilic bacterial isolates recovered from saline soil samples, eight isolates were high amylase producers. Interestingly, the bacterial isolate AHB6 exhibited the highest extracellular amylase production and was selected for further studies. This isolate was molecularly identified based on the 16srRNA gene sequencing as Cytobacillus oceanisediminis and has the accession number OM759999. The optimum temperature for α-amylase enzyme was 45 °C and exhibited thermostability at 45 °C for 1 h and retained more than 80% of its original activity. The α-amylase enzyme was active in almost all tested pHs and reached its highest activity at pH 9. Also, the optimum culture conditions for α-amylase enzyme production were wheat bran as carbon source, 2 g/l K2HPO4 as potassium source, 6 g/l MgSO4 as magnesium source and 0.5 g/l KNO3 as nitrogen source. These findings suggest the applicability of bacterial isolate Cytobacillus oceanisediminis as a potent producer of α-amylase for industrial purposes. Keywords: Amylase; Optimization; Cytobacillus oceanisediminis; Starch hydrolysis; Thermo-halophilic bacteria.

Production, purification, and determination of the biochemical properties of β-glucosidase in Trichoderma koningii via solid substrate fermentation.

The β-glucosidase enzyme was obtained from Trichoderma koningii Oudem. NRRL 54330 under optimal conditions by solid substrate fermentation (SSF) using corn cobs as substrate. The enzyme was purified by two-step procedures, ammonium sulphate precipitation and cefarose-4B-l-tyrosine-1-naphthylamine hydrophobic interaction chromatography, followed by biochemical and kinetic characterisation. The β-glucosidase was obtained from T.koningii using ground corn cob as substrate and Na2HPO4, pH 9, as humidification medium. The optimum conditions for enzyme production by SSF were 30 °C and 6days. The purification efficiency of the obtained β-glucosidase was calculated to be 22.56-fold with a yield of 73.51 %. In the determination of β-glucosidase activity, p-nitrophenyl-β-d-glucopyranoside (pNPG) substrate was used, and the optimum pH and temperature values at which β-glucosidase showed high activity were determined to be pH 3.0 and 75 °C. The purity of the enzyme and the presence/number of subunits were checked using two different electrophoretic methods, SDS-PAGE and NATIVE-PAGE electrophoretic methods. The K m and V max values of the purified enzyme were determined to be 0.16 mM and 2000 EU respectively. Itwas also found that d-(+)-glucose and δ-gluconolactone inhibitors exhibited competitive inhibition of β-glucosidase in the presence of pNPG.

Screening of a Saccharomyces cerevisiae Strain with High 3-Methylthio-1-Propanol Yield and Optimization of Its Fermentation Conditions.

3-Methylthio-1-propanol (3-Met) is an important flavor compound in various alcoholic beverages such as Baijiu and Huangjiu. To maintain the content of 3-Met in these alcoholic beverages, it is necessary to screen a micro-organism with high yield of 3-Met from the brewing environment. In this study, the ability of yeast strains from the Baijiu brewing to produce 3-Met was analyzed, aiming to obtain yeast with high-yield 3-Met, and its fermentation conditions were optimized. Firstly, 39 yeast strains were screened using 3-Met conversion medium. The results showed that the majority of the strains from Baijiu brewing sources could produce 3-Met, and nearly half of the strains produced more than 0.5 g/L of 3-Met. Among these, yeast F10404, Y03401, and Y8#01, produced more than 1.0 g/L of 3-Met, with yeast Y03401 producing the highest amount at 1.30 g/L. Through morphological observation, physiological and biochemical analysis, and molecular biological identification, it was confirmed that yeast Y03401 was a Saccharomyces cerevisiae. Subsequently, the optimal fermentation conditions for 3-Met production by this yeast were obtained through single-factor designs, Plackett-Burman test, steepest ascent path design and response surface methodology. When the glucose concentration was 60 g/L, yeast extract concentration was 0.8 g/L, L-methionine concentration was 3.8 g/L, initial pH was 4, incubation time was 63 h, inoculum size was 1.6%, shaking speed was 150 rpm, loading volume was 50 mL/250 mL, and temperature was 26 °C, the content of 3-Met produced by S. cerevisiae Y03401 reached a high level of 3.66 g/L. It was also noteworthy that, in contrast to other study findings, this yeast was able to create substantial amounts of 3-Met even in the absence of L-methionine precursor. Based on the clear genome of S. cerevisiae and its characteristics in 3-Met production, S. cerevisiae Y03401 had broad prospects for application in alcoholic beverages such as Baijiu.

Energy, techno-economic analysis, and life cycle assessment for co-gasification of polyethylene terephthalate and olive husk by chemical process simulation

Waste-to-energy is emerging as a promising technology that can reduce greenhouse gas emissions and solve waste disposal problems. This study focused on hydrogen production technology through waste gasification. Polyethylene terephthalate (PET), which has a high calorific value was selected as a waste fuel, and biomass of olive husk, which can reduce the problems of gasification for PET, was selected as an additional fuel. In this study, hydrogen production research was conducted through mixed gasification of plastic and biomass, and process simulation was performed using Aspen Plus. Gasifier temperature and steam/fuel ratio were set as major variables to confirm their influences on the co-gasification reaction, and the production of H2, CH4, CO, and CO2, which are the main products of the gasification reaction, was analyzed. In addition, the techno-economic analysis and life cycle assessment were conducted. Based on the analysis results, optimal conditions for hydrogen production were discussed.

Synthetic co-culture in an interconnected two-compartment bioreactor system: violacein production with recombinant E. coli strains.

The concept of modular synthetic co-cultures holds considerable potential for biomanufacturing, primarily to reduce the metabolic burden of individual strains by sharing tasks among consortium members. However, current consortia often show unilateral relationships solely, without stabilizing feedback control mechanisms, and are grown in a shared cultivation setting. Such 'one pot' approaches hardly install optimum growth and production conditions for the individual partners. Hence, novel mutualistic, self-coordinating consortia are needed that are cultured under optimal growth and production conditions for each member. The heterologous production of the antibiotic violacein (VIO) in the mutually interacting E. coli-E. coli consortium serves as an example of this new principle. Interdependencies for growth control were implemented via auxotrophies for L-tryptophan and anthranilate (ANT) that were satisfied by the respective partner. Furthermore, VIO production was installed in the ANT auxotrophic strain. VIO production, however, requires low temperatures of 20-30°C which conflicts with the optimum growth temperature of E. coli at 37°C. Consequently, a two-compartment, two-temperature level setup was used, retaining the mutual interaction of the cells via the filter membrane-based exchange of medium. This configuration also provided the flexibility to perform individualized batch and fed-batch strategies for each co-culture member. We achieved maximum biomass-specific productivities of around 6mg (gh)-1 at 25°C which holds great promise for future applications.

A Comparative Study about Production of Va nadium Carbide via Self Propagating High Temperature Synthesis and Reduction

Vanadium carbide is important for industrial applications because of its high hardness, high temperature resistance, high chemical, and thermal stability. It is generally obtained from the reaction between V and C powders at a high temperature ranging from 1100 to 1500°C. Investigations on these high strength, high abrasion resistant, hard materials have been intensified in recent years and consequently, significant improvements have been achieved. In this study, VC alloys are produced with low cost processes, by reducing the oxides of their components by SHS methods and ball mill-assisted carbothermal reduction. In the experimental stage, V2O5 was used as oxidized Vanadium source, Cblack as carbon source, magnesium and Cblack as reductant. In the study, VC powders were synthesized by two different methods and optimum production conditions were determined. Furthermore, the effect of different stoichiometric charge components and the effect of experiment durations were realized by X-ray diffraction, HSC Chemistry, and SEM analyses for different reductants.

Optimization of fermentation conditions and medium components for chrysomycin a production by Streptomyces sp. 891-B6

BackgroundChrysomycin A (CA) is a promising antibiotic for treatment of Gram-positive bacterial infections and cancers. In order to enhance CA yield, optimization of fermentation conditions and medium components was carried out on strain Streptomyces sp. 891-B6, an UV-induced mutant with improved CA titer compared with its wide-type marine strain 891.ResultsUsing one-way experiment, the optimal fermentation conditions for CA production in 1-L shake flask were obtained as follows: 12 days of fermentation time, 5 days of seed age, 5% of inoculum volume ratio, 200 mL of loading volume and 6.5 of initial pH. By response surface methodology, the optimal medium components determined as glucose (39.283 g/L), corn starch (20.662 g/L), soybean meal (15.480 g/L) and CaCO3 (2.000 g/L).ConclusionValidation tests showed that the maximum yield of CA reached 1601.9 ± 56.7 mg/L, which was a 60% increase compared to the initial yield (952.3 ± 53.2 mg/L). These results provided an important basis for scale-up production of CA by strain 891-B6.

Optimization of conditions for production of pectinase in solid-state fermentation with Aspergillus flavus using dried Assam lemon peel powder as substrate

The culture conditions for pectinase production with Aspergillus flavus by solid-state fermentation (SSF) using dried Assam lemon peel were optimized and the pectinase was used for clarification of grape juice. A central composite rotatable design (CCRD) was used for optimization experiments with moisture content (50–90 %), incubation temperature (20–60 ℃), incubation time (96 h–192 h), and urea concentration (0–1 %) as independent variables, and pectinase activity as dependent variable. The optimum conditions for pectinase production obtained were moisture content of 60 %, incubation temperature of 50 ℃, incubation time of 96 h, and urea concentration of 0.30 % with a pectinase activity of 3.68 ± 0.20 U/mL where one unit of pectinase activity corresponds to number of µmole of galacturonic acid released in one minute in 1 % pectin solution at 37 °C and 4.8 pH. The crude pectinase was found to have maximum activity at a temperature of 40 ℃ and pH 4 and had an apparent Vmax and Km of 6.10 U/mL and 6.62 mg/mL respectively. The grape juice clarified using the crude pectinase showed decreased optical density (1.45 ± 0.06 to 1.17 ± 0.07) and viscosity (1.76 ± 0.10 to 1.46 ± 0.07 mPa.s) and increased reducing sugar content (13.90 ± 0.10 to 16.96 ± 0.06 g/100 mL juice), and total soluble solids (17.77 ± 0.16 to 18.50 ± 0.30 °Brix).

Screening of cellulose-degrading bacteria and optimization of cellulase production from Bacillus cereus A49 through response surface methodology

Cellulose-degrading microorganisms hold immense significance in utilizing cellulose resources efficiently. The screening of natural cellulase bacteria and the optimization of fermentation conditions are the hot spots of research. This study meticulously screened cellulose-degrading bacteria from mixed soil samples adopting a multi-step approach, encompassing preliminary culture medium screening, Congo red medium-based re-screening, and quantification of cellulase activity across various strains. Particularly, three robust cellulase-producing strains were identified: A24 (MT740356.1 Brevibacillus borstelensis), A49 (MT740358.1 Bacillus cereus), and A61 (MT740357.1 Paenibacillus sp.). For subsequent cultivation experiments, the growth curves of the three obtained isolates were monitored diligently. Additionally, optimal CMCase production conditions were determined, keeping CMCase activity as a key metric, through a series of single-factor experiments: agitation speed, cultivation temperature, unit medium concentration, and inoculum volume. Maximum CMCase production was observed at 150 rpm/37 °C, doubling the unit medium addition, and a 5 mL inoculation volume. Further optimization was conducted using the selected isolate A49 employing response surface methodology. The software model recommended a 2.21fold unit medium addition, 36.11 °C temperature, and 4.91 mL inoculant volume for optimal CMCase production. Consequently, three parallel experiments were conducted based on predicted conditions consistently yielding an average CMCase production activity of 15.63 U/mL, closely aligning with the predicted value of 16.41 U/mL. These findings validated the reliability of the model and demonstrated the effectiveness of optimized CMCase production conditions for isolate A49.

Comparisons on Growth Performance, Survivability, Organoleptic Qualities and Economic Feasibility of Asian Seabass (Lates calcarifer) Reared in Different Salinities

Asian seabass, Lates calcarifer is among the most cultured aquaculture species in the Southeast Asian region due to its remarkable tolerance for a diverse environmental fluctuation. In aquaculture, salinity has a direct influence on many biological, physiological and market value of any cultured fish. This study investigated the impacts of different salinities (0, 15, & 30 ppt) on Asian seabass growth, body indices, feeding performance, organoleptic qualities, and production cost for 85 days. Ninety fish were reared in 700-liter tanks equipped with recirculation system with 10 fish each tank. They were fed with commercial marine feed. The findings revealed Asian seabass in 15 ppt attained significantly higher (p>0.05) body weight (470.40 ± 41.16 g), total length (31.51 ± 0.81 cm), total feed intake (309.28 ± 35.66 g/fish) and daily feed intake (3.64 ± 0.42 g/fish/day) compared to 30 ppt but remained insignificant with 0 ppt. Meanwhile, there was no significant difference (p<0.05) in terms of body weight gain, specific growth rate, body indices, and feed conversion ratio of Asian seabass when reared in different salinities. The organoleptic qualities showed that rearing Asian seabass in different salinities has no significant effect (p<0.05) on odour, appearance, texture, and flavour score. However, the overall acceptance score of Asian seabass reared in 30 ppt (3.53 ± 0.22) was significantly higher (p>0.05) compared to 15 ppt but remained insignificant with 0 ppt. Economically, Asian seabass cultured in 15 ppt yielded the most optimal conditions for profitable production. The findings conclude 15 ppt can promotes enhanced growth performance and profitability, while 0 ppt and 30 ppt can promote consumer acceptance positively.

Investigation of Optimum Production Conditions and the Stability of β-Cyclodextrin-Perfluorocarbon Nanocone Clusters for Histotripsy Applications.

Nanocone clusters (NCCs) have been developed as clusters with inclusion complexes of FDA-approved β-cyclodextrin (βCD) and perfluorocarbons (PFC) (i.e., perfluoropentane (PFP) and perfluorohexane (PFH)) and have shown promise in nanoparticle-mediated histotripsy (NMH) applications owing to their lowered cavitation threshold, ease of production, and fluorocarbon quantification. However, there is still a lack of information on the best conditions of the synthesis of NCCs as a product that can have a maximum determinable fluorocarbon content and maintain the stability of the NCC during synthesis and when used as histotripsy agents or exposed to physiological conditions. These concerns about the stability of the clusters and the best possible formulation are investigated in the current work. The cluster formation potential was tested taking into consideration the nature of both PFCs and βCD by employing different synthesis conditions in terms of solution and environmental parameters such as concentration of solvent, stoichiometry between βCD and PFCs, temperature, pH, solvent type, etc. The best route of synthesis was then translated into various batch sizes and investigated in terms of the PFC loading and yield. These studies revealed that preparing NCCs in double-distilled water in an ice bath at the optimized solution concentration gave the highest yields and optimal PFC loading, as determined from gas chromatography. Furthermore, the stability of the clusters with different stoichiometries was scrutinized in varying concentrations, mechanical disruption times, pH levels, and temperature conditions, showing effects on each cluster's particle size in dynamic light scattering, visualized in transmission electron microscopy, and cavitation behavior in agarose gel tissue phantoms. These studies revealed stable clusters for all formulations, with PFH-containing NCCs emerging to be the most stable in terms of their cluster size and bubble formation potential in histotripsy. Finally, the shelf life of these clusters was investigated using DLS, which revealed a stable cluster. In conclusion, NCCs have shown high stability in terms of both synthesis, which can be replicated in gram-level production, and the cluster itself, which can be exposed to harsher conditions and still form stable bubbles in histotripsy.