Bran Medium Research Articles

Evaluation of high-value bioproducts production by marine endophytic fungus Arthrinium sp. FAKSA 10 under solid state fermentation using agro-industrial wastes

BackgroundTo address public health challenges, there is increasing interest in bioactive metabolites from unconventional sources for targeted cancer and viral treatments with minimal side effects. Endophytic fungi are promising for these therapies. This study focused on maximizing bioactive agent yields from these fungi using a low-cost medium and optimized fermentation system. ResultsForty-three endophytic fungi isolated from Sinularia polydactyla were cultivated on wheat bran medium and evaluated for bioactive metabolites under solid-state fermentation. Strain FAKSA 10, identified as Arthrinium sp. FAKSA 10, exhibited the highest levels of pharmaceutical metabolites, including L-glutaminase, L-methioninase, L-arginase, L-asparaginase, L-tyrosinase, L-lysine α-oxidase, and ribonuclease, with a 79.12% hepatitis C virus knockdown rate. This strain produced 46 metabolites with anticancer, antioxidant, antiviral, and cytotoxic properties, including major compounds like hexadecanoic acid methyl ester; hexadecanoic acid ethyl ester; 9, 12-octadecadienoic acid (Z, Z), methyl ester; 9-octadecenoic acid (Z)-, methyl ester, and 11, 14-eicosadienoic acid, methyl ester. A cost effective strategy using 11 agro-industrial residues was applied, following by optimization of the solid-state fermentation system. This optimization increased enzyme yields and enhanced antiviral and antioxidant activities. The optimal conditions for solid-state fermentation were a 10 d incubation, 1 mm particle size, 60% initial moisture, 28°C temperature, and 2 × 107 CFU/mL inoculum size. ConclusionsThis study exploited Arthrinium sp. FAKSA 10 metabolites as natural pharmaceuticals against cancer and viral diseases, highlighting their significant antioxidant properties. Among various residues, oil cakes emerged as an effective and cost-efficient medium, capable of significantly enhancing the production of valuable bioactive metabolites.

Enhanced saccharification levels of corn starch using as a strategy a novel amylolytic complex (AmyHb) from the thermophilic fungus Humicola brevis var. thermoidea in association with commercial enzyme.

Amylases represent a versatile group of catalysts that are used for the saccharification of starch because they can hydrolyze the glycosidic bonds of starch molecules to release glucose, maltose, and short-chain oligosaccharides. The amylolytic complex of the thermophilic filamentous fungus Humicola brevis var. thermoidea (AmyHb) was produced, biochemically characterized, and compared with the commercial amylase Termamyl. In addition, the biotechnological application of AmyHb in starch saccharification was investigated. The highest production was achieved using a wheat bran medium at 50°C for 5-6days in solid-state fermentation (849.6 ± 18.2U·g-1) without the addition of inducers. Optimum amylolytic activity occurred at pH 5.0 at 60°C, and stability was maintained between pH 5.0 and 6.0, with thermal stability at 50-60°C, especially in the presence of Ca2+. These results were superior to those found with Termamyl. Both enzymes were strongly inhibited by Hg2+, Cu2+, and Ag+; however, AmyHb displayed increased activity in the presence of Mn2+ and Na+. In addition, AmyHb showed greater tolerance to a wide range of ethanol concentrations. AmyHb appears to be a complex consisting of glucoamylase and α-amylase, based on its substrate specificity and TLC. The hydrolysis tests on cornstarch flour showed that the cocktail of AmyHb50% + Termamyl50% significantly increased the release of glucose and total reducing sugars (36.6%) when compared to the enzymes alone. AmyHb exhibited promising physicochemical properties and good performance with commercial amylase; therefore, this complex is a biotechnological alternative candidate for the bioprocessing of starch sources.

Structural characteristics and in vitro starch digestibility of oil-modified cooked rice with varied addition manipulations

Lipid has crucial applications in improving the quality of starchy products during heat processing. Herein, the influence of lipid modification and thermal treatment on the physicochemical properties and starch digestibility of cooked rice prepared with varied addition manipulations was investigated. Rice bran oil (RO) and medium chain triglyceride oil (MO) manipulations were performed either before (BC) or after cooking (AC). GC–MS was applied to determine the fatty acid profiles. Nutritional quality was analyzed by quantifying total phenolics, atherogenic, and thrombogenic indices. All complexes exhibited higher surface firmness, a soft core, and less adhesive. FTIR spectrum demonstrated that the guest component affected some of the dense structural attributes of V-amylose. The kinetic constant was in the range between 0.47 and 0.86 min−1 wherein before mode presented a higher value. The lowest glucose release was observed in the RO_BC sample, whereas the highest complexing index was observed in the RO_AC sample, indicating that the dense molecular configuration of complexes that could resist enzymatic digestion was more critical than the quantity of complex formation. Despite the damage caused by mass and heat transfer, physical barrier, intact granule forms, and strengthened dense structure were the central contributors affecting the digestion characteristics of lipid-starch complexes.

Assessment of mycotoxin sequestration efficacy in Saccharomyces cerevisiae by-products cultured in wheat bran and whey protein medium

Mycotoxins are metabolic products of fungi found in feed for farm animals and pose a major threat to food safety due to their adverse health effects. The development of strategies to reduce their bioavailability is crucial. In this context, the cell wall components of Saccharomyces cerevisiae (YCW), especially β-d-glucans and Mannan-oligosaccharide, have been recognized as potent mycotoxin binders. The objective of this research was to develop a novel culture medium to increase the biomass yield of S. cerevisiae and optimize cell disruption by stepwise physical lysis and hydrolytic preconditioning. This process resulted in a yield of approximately 56% reducing saccharides and 28.54% protein. Subsequently, the β-glucan was extracted after cell wall sequestration. The isolated YCW and extracted β-glucan were characterized both individually and synergistically to evaluate their antibacterial properties and analyze their Fourier transform infrared (FTIR) spectra. In vitro evaluation of antibacterial activity revealed that a concentration greater than 250 μg/mL of YCW-β-glucan blend significantly inhibited the growth of Gram-negative bacteria. In addition, this blend showed good adsorption of various mycotoxins, including Aflatoxin B1, Ochratoxin A, and Zearalenone, the latter of which exhibited a remarkable adsorption rate of 80.85%. This study highlights the promising potential of a combination of YCW and β-glucan as a robust strategy to address the pervasive problem of mycotoxin contamination in feed.

Mannitol improves Monascus pigment biosynthesis with rice bran as a substrate in Monascus purpureus.

To reduce the production cost of Monascus pigments (MPs), the utilization of rice bran (RB), an agricultural waste product, as a substrate in submerged fermentation was conducted in this study. To improve MP production, different nutritional ingredients including mannitol (Man), NH4NO3 (AN), ZnSO4 (Zn), and optimization (Opti), which was a synthesis of the three above ones, were added in rice bran (RB) medium. The yields of MPs, pigment constituents, and growth and development of Monascus purpureus M9 were investigated in this study. Man had the maximum color value of 3,532 U/g, which was 18.69 times more than that of RB and reached up to 76.65% of the value of rice (Rice) fermentation. Man significantly increased the production of two orange pigments, monascorubrin and rubropunctatin, of which the yields were 69.49 and 95.36% of the counterpart of Rice. The biomass and colony diameter of Opti presented the maximum value among different groups. AN and RB induced more asexual spore formation, whereas Opti and Man promoted sexual spore production. Comparative transcriptomic analysis showed that different nutritional ingredients led to changes in pigment production, promoting the growth and development of M. purpureus M9 through the regulation of related gene expression. Man and Opti improved MP production by regulating the primary metabolism, including the Embden-Meyerhof pathway (EMP), the pentose phosphate (PP) pathway, the tricarboxylic (TCA) cycle, fatty acid degradation (FAD), fatty acid biosynthesis (FAB), amino acid metabolism (AAM), and fructose and mannose metabolism (FMM), to provide the precursors (acetyl-CoA and malonyl-CoA) for MP biosynthesis. This study presents a low-cost method for increasing MP production and explains the molecular mechanisms of different nutritional ingredients for enhancing MP biosynthesis.

First Report of Leaf Spot Disease Caused by Epicoccum nigrum on Smooth Bromegrass (Bromus inermis) in China.

Smooth bromegrass (Bromus inermis Leyss.) is an excellent forage species widely distributed in Gansu, Qinghai, Inner Mongolia, and other provinces of China (Gong et al. 2019). In July 2021, typical leaf spot symptoms were observed on the leaves of smooth bromegrass plants in Ewenki Banner of Hulun Buir, China (49°5'8″N, 119°44'28″E, alt. 622.5 m). Approximately 90% of plants were affected, with symptoms apparent throughout the plant but mainly concentrated on the lower middle leaves. We collected 11 plants to identify the causal pathogen of leaf spot on smooth bromegrass. Samples (5×5 mm) of symptomatic leaves were excised and surface-sanitized with 75% ethanol for 3 min, rinsed three times with sterile distilled water, and incubated on water agar (WA) at 25℃ for three days. The lumps were cut along the edges and transplanted to potato dextrose agar (PDA) for subculture. After two purification cultures, ten strains, termed HE2 to HE11, were collected. The front side of the colony morphology was cottony or woolly, the center was greyish-green, circled with greyish-white color, with reddish pigmentation on the reverse. The conidia were globose or subglobose, yellow-brown or dark brown, with surface verrucae, and 23.89±3.76×20.28±3.23 μm (n = 50) in size. The morphological characteristics of the mycelia and conidia of the strains mtched those of Epicoccum nigrum (El-Sayed et al. 2020). The primers ITS1/ITS4 (White et al. 1991), LROR/LR7 (Rehner and Samuels 1994), 5F2/7cR (Sung et al. 2007), and TUB2Fd/TUB4Rd (Woudenberg et al. 2009) were used to amplify and sequence four phylogenic loci (ITS, LSU, RPB2 and β-tubulin), respectively. The sequences of ten strains have been deposited in GenBank, and the detailed accession numbers were shown in Table S1. BLAST analysis of these sequences showed 99-100%, 96-98%, 97-99% and 99-100% homology with the E. nigrum strain in the ITS, LSU, RPB2 and TUB sequenced regions, respectively. The sequences of ten test strains and other Epicoccum spp. strains obtained from GenBank were aligned by ClustalW by MEGA (version 11.0) software. After a series of alignment, cutting and splicing, the phylogenetic tree was constructed by the neighbor-joining method with 1000 bootstrap replicates based on the ITS, LSU, RPB2, and TUB sequences. The test strains were clustered together with E. nigrum, with branch support rate of 100%. Combined with morphological and molecular biological characteristics, ten strains were identified as E. nigrum. For the pathogenicity test, the seeds of smooth bromegrass were soaked for four days and then sown into six pots (10 cm diameter × 15 cm height) and kept in a greenhouse under a 16-h photoperiod with temperatures of 20-25°C and 60% relative humidity. Microconidia of the strain produced on wheat bran medium after 10 days were washed with sterile deionized water, filtered through three layers of sterile cheese cloth, quantified, and the concentration adjusted to 1 × 106 microconidia/ml with a hemocytometer. When the plants had grown to a height of about 20 cm, the leaves of plants in three pots were sprayed with the spore suspension, 10 mL per pot, while the remaining three pots were inoculated with sterile water and served as controls (LeBoldus and Jared 2010). The inoculated plants were cultured in an artificial climate box under a 16-h photoperiod with temperatures of 24°C and 60% relative humidity. Brown spots were apparent on the leaves of the treated plants after five days, whereas the leaves of the controls remained healthy. The same E. nigum strain were re-isolated from the inoculated plants and identified by the morphological and molecular techniques described above. To our knowledge, this is the first report of leaf spot disease caused by E. nigrum on smooth bromegrass in China, as well as in the world. Infection with this pathogen could reduce the yield and quality of smooth bromegrass production. For this reason, strategies for the management and control of this disease should be developed and implemented.

A comparative study of the ability of the fungus Aspergillus niger on two alternative media, wheat bran and rice husk.

Citric acid is one of the important organic acids in the fields of industry, agriculture, medicine, etc., and it can be obtained in many ways, the best of which is biological methods using microorganisms. The current study aimed to prepare two cheap and environmentally friendly culture media for the purpose of producing citric acid from Aspergillus niger. The two media, one from rice husks and the other from Wheat bran, where a comparison was made between them regarding which is more efficient in supporting the fungus A. niger compared to the standard medium, the best temperature and pH for production were also assessed.
 Eight isolates were obtained, all of which produced acid to varying degrees. No.1 was the highest and best in terms of production 3.1 gm/l, followed by isolate No. 2 with an amount of 2.5 g/l. It was observed that the amount of acid produced increased with the increase of the biomass of the fungus.
 The study showed variable results regarding the production of citric acid from isolates of A. niger, where the wheat bran medium was the best result, where the resulting concentration of acid was 5.1 gm/l, compared to 4.4 g/l for the medium of rice husks.
 The results showed that the best temperature was 25°C, as it gave a concentration of citric acid of 3.4 g/l, while the best pH was 6 where the concentration of citric acid produced It was 3 grams per liter.the study showed that there were no significant differences with regard to the sugars adopted in this experiment, as it gave significant similar results in terms of the amount of acid produced as well as the biomass of the fungus Aspergillus niger, while ammonium nitrate was the best among the nitrate sources used, with a production quantity of 4 gm/l .

Growth Promoting Role of Phytase Producing Bacteria Isolated from Bambusa tulda Roxb. Rhizosphere in Maize Seedlings Under Pot Conditions

Phytase enzymes have focused on their role in agriculture to generate bioavailable phosphorus (P) requires for plant nutrition. Herein, the feasibility of phytase-producing microbes as biofertilizers was studied. Bacteria with greater potential for hydrolysing calcium phytate based on the halo-to-colony ratio from Bambusa tulda Roxb. rhizosphere was isolated. Phytase activity by incorporating wheat bran, phytase screening and Luria Bertani (LB) medium after acetone precipitation was measured. Bacterial genomes were screened for the presence of β-propeller phytase gene corresponding to the Bacillus spp. using polymerase chain reaction (PCR). Finally, the effect of the isolates on the growth of maize seedlings under pot conditions in P-deficient loamy soil was evaluated. Ten distinct bacterial isolates collected from B. tulda rhizosphere were capable of mineralizing phytate and the maximum effect was observed for designated SRBR-04. Most isolates solubilized Ca3(PO4)2 as a sole P source in Pikovskaya’s agar. Five isolates selected for the study synthesized auxin in the LB broth supplemented with 1 mg mL-1 L-Tryptophan (1.63 to 4.5 μg mL-1). Phytase production was highest in wheat bran with isolate SRBR-04 producing a maximum of 0.34 U mg-1. Two isolates (SRBR-01, SRBR-04) screened positive for the presence of Bacillus phytase gene. Pot assay in P-deficient soil showed significant (p < 0.05) biomass promotion for the isolate SRBR-07 in shoot height (57%), dry shoot weight (178%), dry root weight (104%) and leaf area (113%) over the untreated control. Amendment of P-deficient agricultural soils with phytase-producing bacteria would provide a sustainable approach for P nutrition management in Zea mays.

Novel biosynthesis of MnO NPs using Mycoendophyte: industrial bioprocessing strategies and scaling-up production with its evaluation as anti-phytopathogenic agents

This report provides the first description of the myco-synthesis of rod-shaped MnO NPs with an average crystallite size of ~ 35 nm, employing extracellular bioactive metabolites of endophytic Trichodermavirens strain EG92 as capping/reducing agents and MnCl2·4H2O as a parent component. The wheat bran medium was chosen to grow endophytic strain EG92, which produced a variety of bioactive metabolites in extracellular fraction, which increases the yield of MnO NPs to 9.53 g/l. The whole medium and fungal growth conditions that influenced biomass generation were optimized as successive statistical optimization approaches (Plackett–Burman and Box–Behnken designs). The production improvements were achieved at pH 5.5, WBE (35%), and inoculum size (10%), which increased Xmax to twelve-folds (89.63 g/l); thereby, Pmax increased to eight-folds (82.93 g/l). After 162 h, Xmax (145.63 g/l) and Pmax (99.52 g/l) on the side of µmax and YX/S were determined as 0.084 and 7.65, respectively. ViaTaguchi experimental design, fungus-fabricated MnO NPs reaction was improved by adding 0.25 M of MnCl2·4H2O to 100% of fungal extract (reducing/capping agents) and adjusting the reaction pH adjusted to ~ 5. This reaction was incubated at 60 °C for 5 h before adding 20% fungal extract (stabilizing agent). Also, Pmax was raised 40-fold (395.36 g/l) over the BC. Our myco-synthesized MnO NPs exhibit faster and more precise antagonistic actions against phytopathogenic bacteria than fungi; they could be employed as an alternative and promised nano-bio-pesticide to manage a variety of different types of disease-pathogens in the future.

Tacca Tuber Starch—A Potential Substrate for Enzymatic Production of Glucose Syrup

AbstractGlucose syrup obtainable from enzymatic hydrolysis of cassava and corn is widely used as sweetener in food and pharmaceutical industries. This study evaluates the potential of starch from Tacca tuber in comparison with starch from cassava tuber to produce glucose syrup using amylase from fungal isolates. Spores of amylase‐producing cultures of Aspergillius niger and Rhizopus oligospora are grown on rice bran medium in solid state fermentation. Starch is obtained from Tacca (Tacca leontopetaloides) and cassava tubers using simple methods of extraction methods. Response Surface Method of the Central Composite Design version 6.0.8 is employed for optimization studies on the effect of pH, temperature, and time of hydrolysis on amylase activities of crude enzyme on the extracted starches. In comparison with cassava starch, physicochemical analysis of the glucose syrup obtained from cassava and Tacca tubers gives brix of 44 ° (cloudy appearance) and 40 ° (colourless in appearance) with a dextrose equivalent of 68.58 and 40.4 and specific gravity 1.200 and 1.169, respectively. An assessment of the microbiological quality of the glucose syrup produced shows no coliform or fungal growth. This study presents the potential of Tacca tuber as an economic and safe alternative to cassava starch for glucose syrup production.

Trichoderma sp. Breeding from Bamboo Stems (Schizostachyum brachycladum) and Its Application as an Inoculant for Organic Fertilizer Fermenters According to SNI 7763:2018

This research is an applied study involving the Al Falah farmer group in West Sumatra, Indonesia and was intended to develop a quality organic fertilizer processing technology based on SNI-7763:2018. A Trichoderma sp. culture was bred using bamboo stems (Schizostachyum brachycladum) on a bran medium in an incubator at 39 °C and 75% RH. Cow feces was air-dried for reduced water content from 82% to 60%, mixed with poultry feces (at a ratio of 60:40), and added with 0.3% Trichoderma sp. culture. The mixture was then stacked at a thickness of 70 cm for 7 days. The fermentation results showed an average fermentation temperature of 58 °C and changes in the pH of cow feces and poultry feces from 8.8 to 7.2 and from 3.6 to 6.8, respectively. The following data were also obtained: macronutrient content N = 2.82%, P = 2.78%, and K = 3.21%; organic matter content = 82.89%; C-organic content = 21.20%; C/N ratio = 7.52; and by-products = 1.02%. Based on the results of this research, the organic fertilizer produced complies with SNI-7763:2018.

Extracellular enzymes produced by Coriolopsis rigida an endophytic fungus associated with Cochlospermum regium

Coriolopsis rigida was isolated as an endophytic fungus from the medicinal plant Cochlospermum regium. The fungus was cultivated on solid media containing rice or pineapple crown bran for analyzing the production of extracellular enzymes. The activities of lipase, β-xylosidase, pectinase, fructosyltransferase (FTase), invertase, α-amylase and total cellulolytic (FPase) were determined. The fungus showed positive activity for all enzymes with yield for FTase highest (3.59 ± 0.52 U.gss-1) in pineapple crown bran medium. In general, in pineapple crown bran medium the fungus had a higher enzyme production than in rice medium. Demonstrating the biotechnological potential of C. rigida in the production of enzymes of industrial interest.

Application of Plackett-Burman design for the optimization of protease production by Aspergillus niger

Proteolytic enzymes represent one of the largest groups of industrial enzymes. Fungal proteases have been used for the large-scale production of industrial enzymes. The optimization of enzyme production is a very important objective, where the aim is to further improve the production process. Therefore, the application of an experimental statistical method is essential. In this study, the production of the enzyme protease was carried out by fermentation of a mold (Aspergillus niger) using two media, one based on wheat bran and the other based on peas chick. The optimization of the synthesis of the enzyme was carried out using a statistical method of experimental planning based on the Plackett and Burman matrices. The variables used are the 3 production factors temperature, pH, and substrate concentration. The results were modeled according to multiple linear regression. The results obtained revealed that the strain A.niger gave an excellent activity reaching 740 IU for the wheat bran medium and 194.54 IU for the chickpea medium. The study of pH optima and incubation temperature has shown that the protease produced by A. niger has an optimum pH equal to 6 and an optimum temperature of 40°C for wheat bran medium and has an optimum pH equal to 5 and an optimum temperature of 30°C for chickpeas. The results obtained from the experimental designs of Plackett and Burman proved to be ideal for the selection of factors influencing protease production.

Structure elucidation and immunological activity of a novel exopolysaccharide from Paenibacillus bovis sp. nov BD3526

A novel exopolysaccharide named BD0.4 was purified from the fermentation broth of Paenibacillus bovis sp. nov BD3526 in wheat bran medium via anion exchange column chromatography. Its fine structure was identified by a variety of physical and chemical methods. BD0.4, with the weight average molecular weight of 376 kDa, consisted of glucuronic acid, glucose and fucose in a molar ratio of 1.58:1:1.66. The backbone included 1,3-linked Fuc, 1,3,4-linked Fuc, 1,3-linked Glc and 1,4-linked GlcA residues, with the branching point located at the O4 position of 1,3,4-linked Fuc residues, and the branched chain composed of terminal GlcA residues. BD0.4 could improve the phagocytic ability of macrophages and significantly stimulate the secretion of NO, TNF-α, IL-1β and IL-6 from RAW264.7 cells in a dose-dependent manner. BD0.4 could promote the expression of NF-кB and cause nuclear translocation of NF-κB p65, indicating that BD0.4 probably exerted immune activity through the NF-κB signaling pathway.

APLIKASI CENDAWAN ENTOMOMOPATOGEN Cordyceps militaris PADA HAMA ULAT API (Setothosea asigna) DI PERKEBUNAN SATYA KISMA USAHA UNIT BATANG GADING MUARA BUNGO JAMBI

The aims of this research are to determine the best medium to propagation entomopathogenic fungi C. militaris, to determine effectivity and dosage of C. militaris to control pupae of S. asigna. This research was conducted in plantation of PT. Satya Kisma Usaha Unit Batang Gading, Tanah Tumbuh County, Muara Bungo District, Jambi. The research was conducted from August to September 2020. This study used a non-factorial method, which was arranged in a completely randomizing design (CRD) with 1 factor, namely growth media. The growth media are consisted of corn seeds (M1) and bran (M2) and repeated 5 times. For dosage of fungi used a non-factorial method, which was arranged in a CRD with 1 factor, namely bran media. The bran media dosages are P0 = control (100 ml aquadest/polybag), P1 = 10 g C. militaris + 100 ml aquadest/polybag, P2 = 20 g C. militaris + 100 ml aquadest/polybag, P3 = 30 g C. militaris + 100 ml aquadest/polybag P4 = 40 g C. militaris + 100 ml aquadest/polybag and all of them are repeated 4 times. The results showed that bran medium is the best medium for fungi propagation. C. militaris was effectively to control pupae of S. asigna. The best of fungi dosage is P4 = 40 g C. militaris + 100 ml aquadest/polybag. The highest pupae mortality (100%) is achieved at 12 days observation.
 Keywords: entomopathogenic fungi, Cordyceps militaris, bran, Setothosea asigna

Pigment production by Scenedesmus dimorphus using different low‐cost and alternative culture media

AbstractBACKGROUNDThis study investigated the feasibility of producing pigments from Scenedesmus dimorphus using different low‐cost synthetic and alternative media. Thus the influence of nitrogen and phosphorus deficiency, different nitrogen sources and alternative culture media (wheat bran, garlic powder, wheat bran supplemented with garlic powder) on pigment and biomass production was evaluated.RESULTSAmong the three sources of nitrogen studied (ammonium sulfate, urea and sodium nitrate), urea was the cheapest efficient alternative source of nitrogen for pigment production, especially total chlorophylls (67.38 μg L−1 d−1), by this strain, without strongly affecting biomass yield. Phosphorus deficiency had no negative effect on biomass production, but improved the production of zeaxanthin and chlorophyll b by13.1% and 26.8%, respectively, compared to control. Compared to BG‐11 medium, the alternative garlic powder medium increased the biomass yield of S. dimorphus by 5.2 times, improved the productivity of xanthophylls and contributed to the accumulation of β‐carotene.Wheat bran medium was found to be efficient as a zero‐cost culture medium for the production of pigments, where S. dimorphus accumulated twice the total pigment concentration of the control, with high β‐carotene productivity (38.58 ± 11.94 μg L−1 d−1). The addition of garlic powder to wheat bran increased the biomass (3.14 g L−1) and pigment productivity (216.86 ± 2.06 μg L−1 d−1) by 28.5 and 1.4 times, respectively, but inhibited zeaxanthin biosynthesis. This alternative medium reduced biomass and pigment production costs by 99.80% and 96.21%, respectively.CONCLUSIONWheat bran supplemented with garlic powder showed good application potential for the industrial production of biomass and pigments from S. dimorphus in open cultivation systems where garlic powder might be used simultaneously for biomass and pigment accumulation, and for biological contamination control. © 2021 Society of Chemical Industry (SCI).

Extraction and Purification of Extracellular L-Glutamate Oxidase from Streptomyces.

The bacterial isolates Streptomyces were obtained from the soil and cultivated in a wheat bran medium, which was used to produce the L-glutamate oxidase enzyme. The extracellular enzyme was then extracted using a cooling centrifugation process to obtain the filtrate that represents the crude enzyme. Afterward, the enzyme purification processes were carried out which included precipitation with ammonium sulfate as a preliminary purification step followed by dialysis to remove the salts. Next, ion-exchange chromatography and gel filtration were used to finish the purification process, and the enzyme activity was determined for each purification step. The results of purification of L-glutamate oxidase enzyme from streptomyces using ammonium sulfate showed that the specific activity was 8.25 units/mg protein with a saturation ratio of 60%. Moreover, the results of purification using a dialysis tube indicated that the specific activity was 9.5 units/mg protein. In addition, the result of purification using diethylaminoethyl cellulose ion column revealed that the specific activity was 25 unit/mg protein and the results of purification using gel filtration showed that the specific activity was 56 units/mg protein which was the best step in the purification process due to high specific activity of the enzyme. The optimum temperature and pH for the activity and stability of the enzyme were tested. Based on the findings, the optimum temperature for the activity of the enzyme was 37 °C. In addition, it was found that the optimum temperature range for the stability of the enzyme was 30-50 °C. Besides, the optimum pH for the activity was 7.0 and the optimum pH range for the enzyme stability was 5.0-7.0.

Production of Protease on Wheat Bran by a Newly Isolated Streptomyces SP. Under Solid State Fermentation

Proteases are a group of enzymes that catalyse the degradation of proteins resulting in the production of their amino acid constituents. In the present study newly isolated Streptomyces sp. was subjected to produce proteases through solid state fermentation while wheat bran was used as substrate. To produce proteases, a local strain Streptomyces sp. was isolated from a soil sample of Ezzemouls saltpan, located in Ain M'lila (East of Algeria). The phenotypic and phylogenetic studies of this strain showed that it represents probably a new species. The SSF production medium for Streptomyces sp. was optimized using Plackett and Burman statistical methods. The results showed a maximum activity on basal wheat bran medium supplemented with 1% fructose. The best SSF humidifying solution was pH 9.0 phosphate buffer at 50% moisture. Protease has an optimum at pH 7.0, which is a typical characteristic of neutral proteases. The optimum temperature was 60°C and proved stable up to 80°C. The results showed that the novel Streptomyces sp. isolate is a good producer of extracellular neutral protease on wheat bran, which can be beneficial for industries. J. Bio-Sci. 29(1): 33-48, 2021 (June)

Screening of Effective Media for Black Soldier Fly Larvae Used in Food Waste Treatment

Objectives : Black soldier fly larvae (BSFL) are organisms that effectively decompose various types of organic waste including food waste, and food waste treatment using BSFL is attracting attention as a sustainable waste treatment method. However, food waste discharged from Korea has a wide variety of properties, and its high salt concentration limits its treatment by BSFL. Therefore, to increase the efficiency of food waste treatment using BSFL, it is necessary to increase the quality of food waste as a production medium for BSFL. In this study, the ratio of protein and fat was adjusted by adding bean sprouts and wheat brans to food wastes treated at high temperature under vacuum, and whether such medium is suitable for rearing BSFL was investigated.Methods : To improve the medium, the ratio of protein and fat was adjusted to approximately 2:1 by adding bean sprouts and bran residue to food waste. Subsequently, the growth and development rate of BSFL reared on chicken feed, food waste, food waste + bean sprouts, food waste + wheat bran were measured. Also, the decomposition rate of each medium was analyzed.Results and Discussion : The growth rate of BSFL grown on food waste + wheat bran medium was similar to that of BSFL reared on chicken feed. The speed of development at day 7 was also the fastest for BSFL reared with food waste + wheat bran medium and chicken feed. These results suggest that the mixed medium to which wheat bran has been added to food waste has the potential to be used as a commercial medium for BSFL production. The survival rate of BSFL was 89% or higher in all media.Conclusions : When food waste was used alone, BSFL development was poor compared to that in media combined with agricultural by-products such as bean sprouts and wheat bran. Therefore, to use food waste as a rearing medium of BSFL, it is necessary to adjust the ratio of protein and fat by adding various agricultural by-products and reduce salinity. For the improvement of food waste treatment technology using BSFL, mass rearing of useful insects such as BSFL, and promotion of the use of agricultural by-products, additional research is needed to optimize the composition of rearing medium based on food waste.

Differential Analysis of Stress Tolerance and Transcriptome of Probiotic Lacticaseibacillus casei Zhang Produced from Solid-State (SSF-SW) and Liquid-State (LSF-MRS) Fermentations.

The property differences between bacteria produced from solid-state and liquid-state fermentations have always been the focus of attention. This study analyzed the stress tolerance and transcriptomic differences of the probiotic Lacticaseibacillus casei Zhang produced from solid-state and liquid-state fermentations under no direct stress. The total biomass of L. casei Zhang generated from liquid-state fermentation with MRS medium (LSF-MRS) was 2.24 times as much as that from solid-state fermentation with soybean meal-wheat bran (SSF-SW) medium. Interestingly, NaCl, H2O2, and ethanol stress tolerances and the survival rate after L. casei Zhang agent preparation from SSF-SW fermentation were significantly higher than those from LSF-MRS fermentation. The global transcriptomic analysis revealed that in L. casei Zhang produced from SSF-SW fermentation, carbohydrate transport, gluconeogenesis, inositol phosphate metabolism were promoted, that pentose phosphate pathway was up-regulated to produce more NADPH, that citrate transport and fermentation was extremely significantly promoted to produce pyruvate and ATP, and that pyruvate metabolism was widely up-regulated to form lactate, acetate, ethanol, and succinate from pyruvate and acetyl-CoA, whereas glycolysis was suppressed, and fatty acid biosynthesis was suppressed. Moreover, in response to adverse stresses, some genes encoding aquaporins (GlpF), superoxide dismutase (SOD), nitroreductase, iron homeostasis-related proteins, trehalose operon repressor TreR, alcohol dehydrogenase (ADH), and TetR/AcrR family transcriptional regulators were up-regulated in L. casei Zhang produced from SSF-SW fermentation. Our findings provide novel insight into the differences in growth performance, carbon and lipid metabolisms, and stress tolerance between L. casei Zhang from solid-state and liquid-state fermentations.