Optimization Of Fermentation Parameters Research Articles

Optimizing the liquid‐state fermentation conditions used to prepare a new Shan‐Zha‐Ge‐Gen formula‐derived probiotic

In this study, we aimed to develop a new Shan-Zha-Ge-Gen formula-derived probiotic by optimizing the parameters of the liquid-state fermentation method. Optimized fermentation parameters were derived using principal component analysis. We investigated the effects of the fermentation time, fermentation strain, material-to-liquid ratio, and carbon content on the active components and antioxidant activity (AA) of the fermented Shan-Zha-Ge-Gen formula. The following optimal fermentation conditions were identified in our study: material-to-liquid ratio, 1:10 (M/V); fermentation time, 72 hr; carbon content, 17%; and fermentation strain, Lactobacillus plantarum ACBC271. Under these optimal conditions, the total flavonoid content, total phenolic content, and puerarin content of the fermented probiotic were 77.04 ± 0.30-mg rutin equivalents/g sample, 33.86 ± 0.49-mg gallic acid equivalents/g sample, and 5.29 ± 0.15-mg/g sample, respectively. The AA of the formula was assessed on the basis of its 1,1-diphenyl-2-pricrylhydrazyl and hydroxyl-scavenging ability and ferric-reducing antioxidant power, which were 16.69 ± 0.20-mg ascorbic acid/g sample, 35.93 ± 0.06-mg ascorbic acid/g sample, and 0.02 ± 0.00-mmol Fe2+/g sample, respectively. Liquid-state fermentation significantly increased the concentrations of the active components and the AA of the probiotic. Collectively, our findings indicate that fermented Shan-Zha-Ge-Gen formula-derived probiotic can serve as a food source for polyphenols with high antioxidant potential. Novelty impact statement We developed a new probiotic, Shan-Zha-Ge-Gen formula-derived food, using raw materials from traditional Chinese medicine. The fermented Shan-Zha-Ge-Gen had increased concentrations of active components and antioxidant activities compared with the traditional Shan-Zha-Ge-Gen formula, which could provide several health benefits to patients with cardiovascular diseases.

Large-Scale Preparation of Highly Stable Recombinant Human Acidic Fibroblast Growth Factor in Escherichia coli BL21(DE3) plysS Strain.

In this study, the optimum human aFGF gene encoding haFGF135 was cloned in pET3c and transferred to Escherichia coli BL21(DE3) plysS. To enhance the yield of fermentation and the expression level of the target protein, the fermentation parameters, including temperature, pH, dissolved oxygen, glucose concentration, ammonium chloride concentration, induction time, and inducer (IPTG) concentration, were optimized. The optimized fermentation parameters were used in large-scale fermentation (30 L). Ion-exchange and heparin-affinity column chromatography techniques were used for separation and purification of rhaFGF135 protein. HPLC, isoelectric focusing electrophoresis, and mass spectrometry were used to detect the purity, isoelectric point, and molecular weight and peptide map of rhaFGF135 protein, respectively. Mitogenic activity of rhaFGF135 protein was detected in NIH-3T3 cells and a full-thickness injury wound diabetic rat model. The production and expression level of rhaFGF135 in the 30-L scale fermentation reached 80.4 ± 2.7 g/L culture and 37.8% ± 1.8%, respectively. The RP-HPLC and SDS-PAGE purity of the final rhaFGF135 product almost reached 100%, and the final pure protein yield was 158.6 ± 6.8 mg/L culture. Finally, the cell and animal experiments showed that rhaFGF135 retained a potent mitogenic activity. The large-scale process of rhaFGF135 production reported herein is relatively stable and time-saving, and thus, it can be used as an efficient and economic strategy for the synthesis of rhaFGF135 at the industrial level.

Optimization, purification, and biochemical characterization of thermoalkaliphilic lipase from a novel Geobacillus stearothermophilus FMR12 for detergent formulations

This study was aimed to produce a high compatible thermoalkaliphilic lipase (TA) with detergents from new thermophilic bacterial strains utilizing fish wastes for industrial application. Among bacterial isolates, a new Geobacillus stearothermophilus FMR12 efficiently utilized fish wastes at a concentration of 20% (w/v), exhibiting highly lipolytic activity at extreme thermal and alkaline pH conditions. Optimized fermentation parameters of TA lipase production were ascertained, promoting the productivity of the TA lipase from 424 to 1038 U/ml. Purification results of TA lipase exposed prominent specific activity of 4788 U/mg, purification fold of 12.44, and 7.8% yield. The purified TA lipase demonstrated outstanding activity and stability in a temperature range of 40–95 °C and pH (4–11), revealing optimal activity at 70 °C and pH 9. The molecular weight of the enzyme was estimated to be 63 kDa. Compared to control, the TA lipase activity was promoted in the presence of calcium chloride. Likewise, Triton X-100 enhanced the activity of the TA lipase, recording 128% of the control enzyme. Interestingly, the TA lipase conserved higher than 90% of its activity after blending with commercial detergents, emphasizing its competence for detergent formulations.

Production, purification, characterization, and biological properties of Rhodosporidium paludigenum polysaccharide.

The yield of marine red yeast polysaccharide (MRYP) obtained from Rhodosporidium paludigenum was increased by optimizing fermentation conditions, and the pure polysaccharide was extracted by column chromatography. The molecular weight of pure MRYP and the ratio of mannose to glucose in components of MRYP were determined. Antioxidant and antibacterial abilities of MRYP were investigated in vitro and in vivo. The optimal fermentation parameters were as follows: Medium 4, pH = 6.72, temperature = 30.18°C, blades speed = 461.36 r/min; the optimized yield reached 4323.90 mg/L, which was 1.31 times the original yield. The sequence of factors that affected the MRYP yield was the blades speed>pH>temperature. The main components of MRYP were MYH-1 and MYH-2. The molecular weights of MYH-1 and MYH-2 were 246.92 kDa and 21.88 kDa, respectively; they accounted for 53.60% and 28.75% of total polysaccharide. In MYH-1 and MYH-2, the proportion of glucose and mannose accounted for 46.94%, 38.46%, and 67.10%, 7.17%, respectively. In vitro, the ability of scavenging DPPH•, •OH, and [Formula: see text] radical was 32.26%, 24.34%, and 22.09%; the minimum inhibitory concentration (MIC) of MRYP was 480 μg/mg. In vivo, MRYP improved the lambs' body weight, antioxidant enzyme activity, and the number of probiotics, but it reduced the feed/gain (F/G) ratio and the number of pathogenic bacteria in 60-days-old lambs.

Comparative profiling of lactic acid bacteria isolates in optimized and spontaneous fermentation of cowpea leaves.

In as much as spontaneous fermentation of cowpea leaves enhances product diversification, the process is rather slow with poor product quality. Limited work has been undertaken to provide input toward standardization of the process and enhancing of product quality. The current study sought to evaluate the in‐process fermentative bacteria profile changes due to the effect of optimization of fermentation process of cowpea leaves. Lactic acid bacteria (LAB) isolates from spontaneous and optimized fermentation were characterized using biochemical tests, whereby optimization was done using the Response Surface Methodology model of the central composite design in the Design Expert Software. The RSM models accounted for 89% and 60% variability in the response variables of pH and titratable acidity, respectively (p < .001). Increasing the sugar concentration and period of fermentation significantly (p < .05) increased the titratable acidity, while reducing the pH. The optimal fermentation parameters were established as sugar and salt concentrations of 5% and 2%, respectively, 16 days of fermentation, pH of 3.8 and titratable acidity of 1.22% with a desirability of 0.859. Of the 13 identified LAB isolates, Lactobacillus brevis and Lactococcus lactis dominated the onset stage of spontaneous fermentation whereas only Lactobacillus brevis dominated the onset stage of optimized fermentation. Additionally, the final stage with the dominant isolates of L. plantarum was longer in the spontaneous fermentation process than in the optimized process. Evidently, optimizing the fermentation process resulted in increasing dominance by heterofermenters in the production of soured cowpea leaves, with the yielded product having enhanced acidity.

Production of Methylselenocysteine in Saccharomyces cerevisiae LG6 by continuous fermentation

Methylselenocysteine (SeMCys) is a seleno amino acid. The Saccharomyces cerevisiae LG6 has been used for the production of SeMCys by continuous fermentation. Glucose media with different initial sodium selenite concentrations were tested to obtain optimal medium and fermentation parameters. The maximal specific growth rate and specific selenium consumption rate (SSCR) were calculated to be 0.162 h−1 and 0.47 mg / g h−1 respectively. The continuous fermentation was optimised by feeding medium at different dilution rates. Simultaneously, sodium selenite solution was pumped into the fermenter and the flow rate was controlled by SSCR. After optimization, the final organic selenium productivity and intracellular selenium content were greatly improved, and which reached 17.88 mg / L h−1 and 4.454 mg / g respectively. Speciation analysis of the selenium yeast showed that 58% of total selenium compounds were in the form of SeMCys. The final concentration of SeMCys reached 5.746 mg / g.

Process optimization in ginseng fermentation by Monascus ruber and study on bile acid-binding ability of fermentation products in vitro

Ginseng (Panax ginseng C. A. Meyer) is a famous Traditional Chinese Medicine, which is widely used to treat cardiovascular disease. Monascus ruber (M. ruber) is a fungus used in food and medicine fermentation, and lovastatin, its metabolite, is used extensively in the treatment of dyslipidemia. In this study, ginseng has been fermented by M. ruber, and the response surface methodology (RSM) was applied to optimize fermentation parameters to obtain optimal fermentation system, with further exploring to lipid-lowering activity of P. ginseng C. A. Meyer–M. ruber fermentation products (PM). The concentration of ginseng, temperature, and rotating speed were set as variables and the lovastatin yield was optimized by a Box–Behnken design (BBD) analyzed by RSM. The binding capacity of PM for sodium taurocholate and sodium cholate was assayed by UV spectrophotometry. The highest content of lovastatin production (85.53 μg g−1) was obtained at a ginseng concentration of 1.96%, temperature of 30.11 °C, and a rotating speed of 160.47 rpm. PM exhibited bile acid binding capacity, which was stronger than unfermented ginseng. The RSM can be used to optimize the fermentation system to obtain the best fermentation process. In addition, the fermentation of ginseng by M. ruber can enhance the lipid-lowering effect.

New knowledge about the biosynthesis of lovastatin and its production by fermentation of Aspergillus terreus.

Lovastatin, and its semisynthetic derivative simvastatine, has great medical and economic importance, besides great potential for other uses. In the last years, a deeper and more complex view of secondary metabolism regulation has emerged, with the incorporation of cluster-specific and global transcription factors, and their relation to signaling cascades, as well as the new level of epigenetic regulation. Recently, a new mechanism, which regulates lovastatin biosynthesis, at transcriptional level, has been discovered: reactive oxygen species (ROS) regulation; also new unexpected environmental stimuli have been identified, which induce the synthesis of lovastatin, like quorum sensing-type molecules and support stimuli. The present review describes this new panorama and uses this information, together with the knowledge on lovastatin biosynthesis and genomics, as the foundation to analyze literature on optimization of fermentation parameters and medium composition, and also to fully understand new strategies for strain genetic improvement. This new knowledge has been applied to the development of more effective culture media, with the addition of molecules like butyrolactone I, oxylipins, and spermidine, or with addition of ROS-generating molecules to increase internal ROS levels in the cell. It has also been applied to the development of new strategies to generate overproducing strains of Aspergillus terreus, including engineering of the cluster-specific transcription factor (lovE), global transcription factors like the ones implicated in ROS regulation (or even mitochondrial alternative respiration aox gen), or the global regulator LaeA. Moreover, there is potential to apply some of these findings to the development of novel unconventional production systems. KEY POINTS: • New findings in regulation of lovastatin biosynthesis, like ROS regulation. • Induction by unexpected stimuli: autoinducer molecules and support stimuli. • Recent reports on culture medium and process optimization from this stand point. • Applications to molecular genetic strain improvement methods and production systems.

Optimization of fermentation parameters for enhanced APHE production from Streptomyces griseocarneus through submerged fermentation

Optimization of fermentation parameters for enhanced APHE production from Streptomyces griseocarneus through submerged fermentation

Optimization of fermentation parameters for high-activity inulinase production and purification from Rhizopus oryzae by Plackett-Burman and Box-Behnken.

The aim of study was to optimize fermentation parameters for inulinase production from Rhizopus oryzae by a statistical approach and to carry out purification of inulinase. Five isolated fungal strains were screen out inulin degradation by using Lugol's iodine solution. R. oryzae exhibited maximum zone of clearance around the colony and was used as an inulinase producer. The effect of carbon sources (inulin, glucose, maltose, sucrose, lactose, onion peel, stevia root, wheat bran) as medium component and fermentation parameters (temperature (25-45°C), initial pH (4-7), time (3-7days)) on inulinase production was investigated by Plackett-Burman Design. Wheat Bran (WB), temperature, pH, and incubation time were found to be significant for the production of inulinase (P < 0.05). Furthermore, Box-Behnken Design was employed to optimize fermentation conditions. The maximum experimental results for inulinase activity and specific activity were 348.36EU/mL and 3621.78EU/mg, respectively. The results were obtained at 5days of incubation time, 35°C of incubation temperature, initial pH of 5.5, and 2% (w/v) WB. Also, inulinase was purified by using ammonium sulfate precipitation, gel filtration chromatography with 2.19-fold and its molecular weight was found as 89.12kDa. The optimal pH and temperature of the purified enzyme were 4.0 and 60°C, respectively. Furthermore, the purified enzyme showed excellent stability at 60°C. In conclusion, the present study offers cost-effective method to produce inulinase from Rhizopus oryzae. Also, it can be suggested that the purified inulinase has strong potential for usage in production of fructose syrup and other industrial areas.

Comparative study on modeling by neural networks and response surface methodology for better prediction and optimization of fermentation parameters: Application on thermo-alkaline lipase production by Nocardiopsis sp. strain NRC/WN5

Abstract Artificial neural network is a mathematical approach that has been utilized with great success in system design, modeling, prediction and optimization. Statistical design has been used for long years in improving microbial fermentations. The current work intended to compare both of the two strategies in optimizing production of thermo-alkaline lipase by Nocardiopsis sp. strain NRC/WN5. The preliminary investigation showed intensive effects of fermentation medium type, time course and their interaction on lipase production. In the best medium, significant effects of carbon source, inorganic and organic nitrogen sources were realized (p = 0.0287, p = 0.00076 and p = 0.000015, respectively). Plackett-Burman design showed significant effects of ten variables on lipase production. The most important factors were sodium chloride, time course and medium pH which possessed more than 78% of total effect exerted on lipase production. Basing on these three factors, very significant model (p = 0.0005) was conducted through Box-Behnken design. To get the best model of neural network, a comparative study on five different models of neural networks was accomplished. The highly predictive model was that based on LBFGS optimization function, sigmoid activation function, 150 iterations and 100 neurons in hidden layer. Coupled with genetic algorithm, the predictive model was used to optimize and predict the variables of optimum fermentation which were experimentally validated in comparison with that obtained from two-step statistical designs. Practical validation showed superiority of lipase production in fermentation developed by neural network coupled with genetic algorithm (62.21 ± 1.7 U/ml) over that developed by two-step statistical design (50.11 ± 2.6 U/ml).

Production of Lactic Acid from Seaweed Hydrolysates via Lactic Acid Bacteria Fermentation

Biodegradable polylactic acid material is manufactured from lactic acid, mainly produced by microbial fermentation. The high production cost of lactic acid still remains the major limitation for its application, indicating that the cost of carbon sources for the production of lactic acid has to be minimized. In addition, a lack of source availability of food crop and lignocellulosic biomass has encouraged researchers and industries to explore new feedstocks for microbial lactic acid fermentation. Seaweeds have attracted considerable attention as a carbon source for microbial fermentation owing to their non-terrestrial origin, fast growth, and photoautotrophic nature. The proximate compositions study of red, brown, and green seaweeds indicated that Gracilaria sp. has the highest carbohydrate content. The conditions were optimized for the saccharification of the seaweeds, and the results indicated that Gracilaria sp. yielded the highest reducing sugar content. Optimal lactic acid fermentation parameters, such as cell inoculum, agitation, and temperature, were determined to be 6% (v/v), 0 rpm, and 30 °C, respectively. Gracilaria sp. hydrolysates fermented by lactic acid bacteria at optimal conditions yielded a final lactic acid concentration of 19.32 g/L.

Isolation of Trametes hirsuta La-7 with high laccase-productivity and its application in metabolism of 17β-estradiol

Estrogens, which are extensive in the eco-environments, are a category of high-toxic emerging contaminants that induce metabolic disorders and even carcinogenic risks in wildlife and humans. Here we investigate whether fungus-secreted laccase can be used as a green catalyst to eliminate a representative estrogen, 17β-estradiol (E2). A white-rot fungus Trametes hirsuta La-7 with high laccase-productivity, was isolated from pig manure-contaminated soil. Extracellular laccase activity expressed by strain La-7 was 65.4 U·mL−1 for a 3 d inoculation under the optimal fermentation parameters. The concentrated-crude laccase from Trametes hirsuta La-7 (CC-ThLac) was capable of effectively metabolizing E2 at pH 4–6, and the apparent pseudo first-order reaction rate constant and half-life values were respectively 0.027–0.055 min−1 and 25.86–12.67 min (R2 > 0.98). The mass measurement of high-resolution mass spectrometry in combination with 13C-isotope labeling identified that the main by-products of E2 metabolism were dimers, trimers, and tetramers, which are consistent with radical-driven C–C and/or C–O–C covalent coupling pathway, involving the initial enzymatic production of phenoxy radical intermediates and then the successive oxidative-oligomerization of radical intermediates. The formation of oligomers dramatically reduced the estrogenic activity of E2. Additionally, CC-ThLac also exhibited high-efficiency metabolism capability toward E2 in the natural water and pig manure, with more than 94.4% and 91.0% of E2 having been metabolized, respectively. These findings provide a broad prospect for the clean biotechnological applications of Trametes hirsuta La-7 in estrogen-contaminated ecosystems.

Degradation of glucosinolates in rapeseed meal by Lactobacillus delbrueckii and Bacillus subtilis

Lactobacillus delbrueckii and Bacillus subtilis were employed as a new combination of strains to treat rapeseed meal by solid-state fermentation, aiming to efficiently degrade the glucosinolates, which are the main toxin in the meal. Single-factor tests and Response surface methodology (RSM) were used to optimize the fermentation parameters. Under the optimum fermentation parameters of 15% total injection volume of the mixture of Lactobacillus delbrueckii and Bacillus subtilis with a ratio of 2:1, bran content of 16%, feed to water ratio of 1:1.5, fermentation temperature of 36 °C and fermentation time of 72 h, the content of glucosinolates in rapeseed meal was decreased from 64.558 μmol/g to 3.473 μmol/g, reaching a high degradation rate (94.62%). The high detoxification rate by a consortium of Lactobacillus delbrueckii and Bacillus subtilis provides a bright application prospect in feed utilization of rapeseed meal.

Statistical evaluation of growth parameters in biofuel waste as a culture medium for improved production of single cell protein and amino acids by Yarrowia lipolytica

Yarrowia lipolytica is an oleaginous yeast species with the ability to grow on a number of substrates types, especially industrial wastes. This paper concerns the statistical optimization of fermentation parameters and media to ensure consistent and improved Y. lipolytica protein production. A strain of Y. lipolytica A-101 was observed to be proficient in producing single cell protein, amino acids, and vitamin B12 while utilizing biofuel waste instead of a complete YPD medium for yeast growth. A fractional fractal design experiment was then applied, and the two fermentation parameters of temperature and pH were recognized to have a significant effect on the protein and amino acid production. Subsequently, the response surface methodology with a three-level complete factorial design was employed to optimize these influential parameters. Therefore, five different measuring systems were utilized to construct a quadratic model and a second-order polynomial equation. Optimal levels of parameters were then obtained by analysis of the model and the numerical optimization method. When the Y. lipolytica A-101 was cultivated at optimized pH (5.0) using biofuel waste as a medium, the protein concentration was increased to 8.28—a 44% enhancement as compared to the original (3.65). This study has thus demonstrated a beneficial way to cultivate Y. lipolytica A-101 on biofuel waste for enhanced production of single cell protein and amino acids for use in human diet and in animal feed.

Optimization for coproduction of protease and cellulase from Bacillus subtilis M-11 by the Box–Behnken design and their detergent compatibility

The aim of the study was to optimize fermentation parameters for coproduction of protease and cellulase from Bacillus subtilis M-11 in solid state fermentation by a statistical approach and to evaluate the stability and compatibility of enzymes for detergent formulation. Eight different substrates were investigated to find the best medium supporting maximum enzyme productions. Box–Behnken design (BBD) was employed to optimize culture conditions for the coproduction of proteases and cellulose. The effect of pH and temperature, surfactants and commercial detergents on stability of the enzymes was evaluated. Oat flour was found to be the best substrate for production of both enzymes. The results indicate that BBD is an effective tool for optimizing the medium for coproduction of enzymes and the fermentation parameters that affect production of the enzymes. Furthermore, the enzymes showed excellent compatibility with detergents, as well as high stability in wide ranges of temperature (25–60 °C) and pH (7.0–9.5). In conclusion, the present study offers a cost-effective method to coproduce protease and cellulase from B. subtilis M-11. Also, it can be suggested that both the enzymes have strong potential for usage in the detergent industry.

Laundry Detergent Compatibility and Dehairing Efficiency of Alkaline Thermostable Protease Produced from Aspergillus terreus under Solid-state Fermentation.

Aspergillus terreus was chosen for production of alkaline protease using solid-state fermentation (SSF). The maximum enzyme yield reached about 34.87 U/mg protein after optimization of fermentation parameters. The produced alkaline protease was purified by precipitation with iso-propanol and then purified through gel filtration and ion exchange column chromatography with a yield of 53.58% and 5.09- fold purification. The enzyme has shown to have a molecular weight of 35 kDa. Optimal pH and temperature for the enzyme activity were 9.5 and 50°C respectively. The highest activity was reported towards casein, with an apparent Km value of 6.66 mg/mL and Vmax was 30 U/mL. The enzyme activity was greatly repressed by phenylmethylsulfonyl fluoride (PMSF). Sodium dodecyl sulfate (SDS) caused activation in enzyme activity. The enzyme retained about 83.8, 70.6, 74.5, 76.4 and 66.4% of its original activity after incubation with Aerial, Leader, Oxi, Persil and Tide, respectively for 8 h at 60°C. Adding of the enzyme in detergents improved the cleansing performance to the blood stains and suggested to be used as a detergent additive. Our outcomes showed that protease could be used as environment green-approach in dehairing process.

Optimization of the fermentation parameters for the production of Ganoderma lucidum immunomodulatory protein by Pichia pastoris

In order to obtain a better fermentation parameter for the production of recombinant Ganoderma lucidum immunomodulatory protein (rFIP-glu), an engineered Pichia pastoris GS115 was investigated on the fermentation time, temperature, methanol concentration and initial pH of media, while immunomodulatory activities of the rFIP-glu was confirmed. L9(33) orthogonal experiment were firstly employed to optimize various fermentation parameters in the shake-flask level. The optimized fermentation parameters were subsequently verified in a 5 L fermenter. Biological activities including cell viability and tumor necrosis factor-alpha (TNF-α) mRNA of the rFIP-glu were evaluated on murine macrophage RAW264.7 cells. The results showed that the yield of rFIP-glu was up to 368.71 μg/ml in the shake-flask, and 613.47 μg/ml in the 5 L fermenter, when the Pichia pastoris was incubated in basic media with the methanol concentration 1.0% and initial pH 6.5, and with constant shaking at 280 rpm for 4 days at 26 °C. In vitro assays of biological activity indicated that rFIP-glu had significant toxicity against RAW264.7 cells, and possessed the ability to induce TNF-α mRNA expression in macrophage RAW264.7 cells. In conclusion, engineered P. pastoris showed a good fermentation property under the optimum fermentation parameters. It could be a candidate industrial strain for further study.

Использование микробных культур в технологии функциональных напитков

Чай является традиционным напитком для многих народов мира. В странах Востока помимо традиционных видов чая использовали напитки, полученные микробной ферментацией листьев чайного растения. Примером является китайский чай Хэй Ча и напиток, полученный ферментацией чайного экстракта – Комбуча. Микробные культуры, используемые для ферментации, придавали напиткам дополнительные функциональные свойства. Целью данного исследования было изучение микроскопических грибов, используемых в технологии чая Хэй Ча, и ассоциации бактерий и дрожжей напитка Комбуча с последующим изучением возможности их использования для получения ферментированных напитков. Из образцов чая Хэй Ча были выделены микроскопические грибы, идентифицированные как E. cristatum, из напитка Комбуча – бактерии рода Acetobacter и дрожжи рода Saccharomyces. Изучено влияние состава ферментированного сырья и режимов культивирования на рост и развитие выделенных микроорганизмов. Определенны оптимальные параметры ферментации и разработана технологическая схема получения готового ферментированного продукта на основе Chamaenerion angustifolium (кипрей узколистный). Показано, что используемые микроорганизмы не синтезируют микотоксины, обладают способностью к синтезу антиоксидантов и витаминов группы В и др. В напитках, полученных ферментацией экстрактов листьев Camellia sinensis (камелий китайская), Chamaenerion angustifolium (кипрей узколистный) было определенно содержание и состав биогенных аминов, аминокислот, фенольных соединений и антиоксидантов. Разработана рецептура напитков с использованием выделенных микробных культур, в состав которых в качестве дополнительных ингредиентов входят мёд, солодовое сусло, сок виноградный, мате, кофе. Безопасность продукта была подтверждена результатами микробиологического анализа. Полученные напитки имеют насыщенный цвет, приятный аромат, кисло-сладкий с фруктовыми оттенками вкус.

L-Asparaginase production in rotating bed reactor from Rhizopus microsporus IBBL-2 using immobilized Ca-alginate beads.

The present work reports on the production of extracellular l-asparaginase from Rhizopus microsporus IBBL-2 using submerged fermentation (SmF) process free of glutaminase and urease activities. Primary studies done in shake flask showed that the highest l-asparaginase activity of 12.68 U mL-1 was produced at 72h with optimized fermentation parameters such as pH 6.0, 4 × 106 fungal cells mL-1, and agitation of 180rpm at 30°C using one-factor-at-a-time (OFAT). Different substrates, nitrogen sources, temperature, pH, the initial number of cells and metal ions were tested to determine the impact on enzyme production. l-Asparaginase activity of 17.68U mL-1 was produced after 48h using immobilized calcium-alginate (Ca-alginate) cells. 4 × 106 cells mL-1 was entrapped in 3% (W/V) of alginate bead of size 2mm each at a temperature of 30°C and pH of 6. The process was optimized using L9 (34) Taguchi Orthogonal Array (OA) technique with a regression coefficient (R 2) value of 0.9709, F value of 33.34 and p value of 0.0025. Scale-up studies involving 200-mL and 1-L rotating bed reactor (RBR) using immobilized beads were done and the results obtained are 20.21 U mL-1 and 19.13 U mL-1, respectively, the increased activity with immobilization accounts for reduced shear on cells due to increased stability as compared to the free-flowing cells.