Submerged Culture Conditions Research Articles

Optimization of Cellulase Production from Agri-Industrial Residues by Aspergillus terreus NIH2624

The objective of this study was to assess the cellulase production of four fungi: Aspergillus terreus NIH2624, Aspergillus clavatus NRRL1, Aspergillus versicolor CBS583.65 and Aspergillus phoenicis ATCC3157, under submerged cultivation conditions. When these fungi were cultured in shake flasks using Mandels and Weber’s minimal medium with 1% sugarcane bagasse as a carbon source and 1.8 g/L of rice bran extract as a nitrogen source, A. terreus showed maximum cellulase production (filter paper activity (FPase) 3.35 U/mL; carboxymethyl cellulase activity (CMCase) 1.69 U/mL). Consequently, A. terreus was selected for the optimization study for cellulase production. Among the different tested carbon sources, A. terreus showed higher CMCase activity when it was cultivated on delignified sugarcane bagasse (1.64 U/mL) and higher FPase activity on sugarcane straw (7.95 U/mL). Regarding the nitrogen sources, the maximum FPase activity was observed when using rice bran (FPase, 8.90 U/mL) and soybean meal (FPase, 9.63 U/mL). The optimized fermentation medium (minimal medium with delignified sugarcane bagasse and rice bran as carbon and nitrogen sources, respectively) resulted in an enzymatic cocktail mainly composed of xylanases, with a maximum activity of 1701.85 U/mL for beechwood xylan, 77.12 U/mL for endoglucanase and 21.02 U/mL for cellobiohydrolase. Additionally, the enzymatic cocktail showed efficient activities for β-glucosidase, β-xylanase, arabinofuranosidase and lytic polysaccharide monoxygenases (LPMOs). This cellulase enzyme solution has the potential to efficiently hydrolyze lignocellulosic biomass, producing second-generation sugars in biorefineries.

Enhancement of Mycelial Biomass Production and Bioactive Properties Related to Cosmeceuticals of Calocybe indica (Milky Mushroom) by Optimization of Submerged Culture Conditions

Calocybe indica or milky mushroom grown in submerged culture was investigated as a new source of antioxidants and anti-collagenase substances, and for its ability to inhibit three bacteria that trigger inflammatory acne, Cutibacterium acnes, Staphylococcus epidermidis, and S. aureus. To facilitate C. indica submerged cultivation and achieve high productivity, a three-level four-factor Box-Behnken design was utilized to find the optimal culture conditions for its mycelial biomass production. The model estimated the optimal conditions as 30 °C, a medium pH of 5.9, and incubation for 14 days under static culture, with results verifi ed by validation experiments. The optimal conditions gave mycelial biomass of 7.12 g/L, which is 5-fold higher than the original condition. This statistical method facilitated rapid identification and integration of key factors for C. indica high mycelial biomass production with significantly improved cosmeceutical properties in terms of antioxidant and antibacterial activities against acne-causing bacteria, especially C. acnes at 19-fold and 18-fold, respectively, compared to the original condition. An ethanolic extract derived from C. indica mycelia was nontoxic to human skin keratinocytes (HaCaT). These diverse functionalities indicate that the mycelial extract of C. indica may represent a promising source of bioactive substances for cosmeceutical applications.

Isolation, purification, and structural elucidation of a water-soluble polysaccharide derived from Phellinus baumii Pilát mycelia

This study involved the successful production of mycelial polysaccharides by optimizing submerged culture conditions of Phellinus baumii Pilát. Then, the investigation focused on the composition and chemical structure of the water-soluble polysaccharide from P. baumii Pilát mycelia (PBMP) by extraction and purification. Specifically, this study indicated that a water-soluble PBMP fraction 1 (PBMP1) was isolated from PBMP. Moreover, this study discovered a PBMP1 isolated from PBMP, which was found to have the monosaccharide compositions comprised of fucose (Fuc), glucose (Glc), and galactose (Gal) despite the absence of proteins. Subsequently, the composition and structure of PBMP1 were characterized using Fourier transform infrared (FT-IR) spectroscopy, periodate oxidation, Smith degradation, methylation reaction, gas chromatography-mass spectrometer (GC-MS), and Nuclear magnetic resonance (NMR). The composition and structure of PBMP1 were characterized in this study, revealing an α-glycosidic bond conformational linkage with 1,4-Glc residues and 1,6-Gal residues forming the backbone. Additionally, a highly branched hetero-polysaccharide was identified with a non-reducing terminus of Fuc containing 1,3,4- and 1,4,6-Glc branching. The findings of this study offer valuable insights and information that can be utilized by researchers, manufacturers, and other stakeholders to advance the field of P. baumii Pilát product development. Moreover, these results have significant implications for future large-scale mass production and functional applications of PBMP1 products.

Production of β-cyclodextrin by immobilized CGTase in packed bed bioreactor through the medium component by employing Taguchi methodology

This study investigates the optimization of submerged culture conditions for the production of extracellular cyclodextrin glucanotransferase (CGTase) enzyme by Bacillus macerans ATCC 8244, employing Taguchi orthogonal array (OA) experimental design methodology. Five critical factors - starch, peptone, temperature, pH, and agitation speed - were examined at two levels using an OA layout of L8 for the experimental design. Analysis revealed a significant enhancement in CGTase yield, with the modified culture conditions resulting in a 21.2% increase from 513.416 U/ml to 622.5 U/ml. The successful application of Taguchi's design methodology underscores its efficacy in optimizing enzyme production processes. This study highlights Taguchi's design potential as a valuable tool for improving CGTase production efficiency while minimizing resource consumption. Additionally, the utilization of a packed bed bioreactor (PBR) facilitated continuous production of β-cyclodextrin (β-CD), demonstrating stability over 10 days with only a slight decrease in productivity. The Km,app value was determined to be 23.4 mg starch/ml, indicating a slight increase.

INFLUENCE OF LOW-INTENSITY LIGHT ON THE BIOSYNTHETIC ACTIVITY OF THE MEDICINAL MACROMYCETE LARICIFOMES OFFICINALIS Laricifomes officinalis (Fomitopsidaceae, Polyporales) in vitro

Understanding the impact of artificial lighting on the biosynthetic and biological activity of medicinal mushrooms will help enhance technologies aimed at obtaining bioactive compounds. The aim of our work was to determine the influence of low-intensity quasi-monochromatic light on biosynthetic activity, including the antioxidant activity of the medicinal fungus Laricifomes officinalis under submerged cultivation conditions. Methods. The effect of light on the biosynthetic activity of L. officinalis was studied using sources of low-intensity coherent monochromatic laser light and quasi-monochromatic radiation of light-emitting diodes (LEDs) with specified spectral-intensity characteristics. Results. The most stimulating effect on the biosynthetic activity of the L. officinalis strain was observed when samples were irradiated with blue (488 nm laser and 470 nm LED) and red (650 nm LED) light. Under these conditions, there was an increase in the synthesis of mycelial mass, polysaccharides, and the quantity of total phenolic compounds. Low-intensity light irradiation caused changes in both the quantitative and qualitative composition of the fatty acid profile of the mycelial mass. Red light irradiation resulted in an increase in the quantity of polyunsaturated fatty acids. A correlation was established between the quantity of total phenolic compounds and antioxidant activity. Conclusions: The research results provide grounds to consider low-intensity visible light as a promising regulator of the biosynthetic activity of L. officinalis in the biotechnology of its cultivation.

Green “one-pot” fluorescent bis-indolizine synthesis with whole-cell plant biocatalysis

Abstract An efficient one-pot route leading to bis-indolizine symmetric compounds has been developed via a new approach from the dipyridinium heterocyclic compound, reactive halogenated derivative, and activated alkyne through biocatalysis. A set of local plants was evaluated for its catalytic potential in “one-pot” biocatalysis of these valuable fluorescent compound synthesis reactions. Most of these biocatalysts containing enzymes from the oxidoreductase class (peroxidase: 0.56–1.08 mmol purpurogallin‧g−1 fresh weight‧min−1, polyphenol oxidase (PPO) : 27.19–48.95 PPO units‧mg tissue−1, CAT: 3.27–21.71 µmol O2‧g−1 fresh weight‧min−1), were used as green catalysts in the multi-component cycloaddition reaction, in an aqueous buffer solution, for the production of bis-indolizine compounds in moderate to excellent yields (45–85%). The horseradish root (Armoracia rusticana) has been selected as the most promising biocatalyst source among the evaluated plants, and the obtained yields were greater than in the conventional synthesis method. The structures of indolizine derivatives were confirmed by nuclear magnetic resonance spectra, elemental analyses, as well as Fourier transform-infrared spectra. The cytotoxicity of the latter obtained indolizine compounds on the growth of the model microorganism, Saccharomyces cerevisiae MIUG 3.6 yeast strain, was also evaluated. Various parameters (number of generations, growth rate, generation time, dry matter yield, the degree of the budding yeast cells, and the degree of yeast autolysis, fermentation intensity), which describe the yeast growth, suggest that the nutrient broth supplemented with different concentrations of bis-indolizine compounds (10 and 1 µM) had no toxic effect on the yeast strain growth, under submerged cultivation conditions.

Utilization of Burkholderia sp. ISTR5 for enhanced saccharification and fermentation of agricultural waste for production and upgradation of biogas by calcite-based bio-composite materials

Utilization of agricultural feedstocks like Sugarcane bagasse, Mustard Husk and Rice plus tobacco Husk by Burkholderia sp. ISTR5 was evaluated under submerged culture conditions. Percent loss of feedstocks, total soluble sugar, saccharification efficiency, bacterial count and FTIR were major factors that indicated sugarcane bagasse to be the best feedstock for the production of Bio-methane as compared to other used feedstocks in the experiment. Further, biogas produced by fermentation process of sugarcane bagasse hydrolysate and fermentation was upgraded with the help of fabricated bio-mineralized product of CO2 sequestrating bacterium, Serratia sp., and biochar. The synthesis of calcite-based bio-composite materials was confirmed by FTIR, FESEM, XRD, EDX. The results indicated the usage of Bagasse was more efficient than other two feedstocks and also the usage of calcite-based bio-composite helped in the upgradation of biogas by removal of CO2 and other contaminants. The results indicated possible applications for in-situ biomethanation and clean energy.

Optimization of Submerged Culture Parameters of the Aphid Pathogenic Fungus Fusarium equiseti Based on Sporulation and Mycelial Biomass.

Fusarium equiseti (JMF-01), as an entomopathogenic fungus, can effectively control agricultural pests and has the potential to be a biocontrol agent. To promote mycelial growth and sporulation, we investigated the optimal submerged culture conditions for F. equiseti. In this study, we used the single-factor method and Box-Behnken design and determined the virulence of the submerged culture against Myzus persicae after optimization. As a result, the highly significant factors affecting the spore concentration of strain JMF-01 were the primary inoculum density and the initial pH, and the highly significant factor affecting the mycelial biomass was the medium-to-flask ratio. The highest mycelial biomass value was 0.35 g when the incubation time was 5.68 days, the initial pH was 5.11, the medium-to-flask ratio was 0.43, and 1 mL of the primary inoculum with spore density of 0.97 × 107 conidia/mL was added. When the incubation time was 6.32 days, the initial pH was 4.46, the medium-to-flask ratio was 0.35, the primary inoculum density was 1.32 × 107 conidia/mL of 1 mL, and the highest spore concentration of 6.49 × 108 blastospores/mL was obtained. Compared with the unoptimized medium conditions, the optimized submerged culture had the highest mycelial biomass and spore concentration, which were 3.46 and 2.06 times higher, respectively. The optimized submerged culture was highly pathogenic toward M. persicae, reaching a 95% mortality rate. Our results provide optimal submerged culture conditions for F. equiseti and lay the basis for later research to expand production for pest control.

Media optimization, extraction, purification and characterization of exopolysaccharide from Fusarium proliferatum: A novel source bioactive polysaccharide

Polysaccharides from fungal source have been proved to be effective in different plethora of biomedical fields. The present study was carried out on exopolysaccharide (EPS) production by Fusarium proliferatum, considered novel fungus as no reports on its EPS production capability has been reported yet. The main objective of this study was to optimize media for better EPS production extracellularly under submerged culture conditions. Among all malt extract broth was selected as favorable medium for EPS yielding 81.4 ± 0.48 mg/l. Optimization revealed 9 days of incubation period, pH 6.0 and temperature 25 °C best for the growth and EPS yield. The medium 12 out of sixteen media was selected as best for the EPS yield which was ensured by various permutation and combinations of chemical factors. The optimized medium includes: malt extract medium (basal medium), xylose 4%, glucose 4%, tryptophan 0.1%, olive oil 3%, Tween 80 0.2%, vitamin C 0.2%, K2HPO4 0.2%, CaCl2 0.5%, pH 6.0, incubation period of 9 days at temperature 25 °C yielding 4067 ± 153.08 mg/l of EPS. HPTLC, FTIR and LCMS analysis exhibited the monomeric composition of maltose, fructose, xylose, galactose, glucose, raffinose and sorbose with functional group of –OH, C=O, C–O–C, C–O, –C–H, COO– with glycosidic likanges and suggested the production of glycan by these fungi. Owing to the existing reports of anti-cancerous property of β-Glycan an in-silico investigation was carried out to which indicatedits higher reactivity and lower binding affinityin comparison to imatinib, an oral chemotherapy drug to treat cancer.

Antifungal Activity of Medicinal Mushrooms and Optimization of Submerged Culture Conditions for Schizophyllum commune (Agaricomycetes).

The main goal of the present study was the exploration of the antifungal properties of Agaricomycetes mushrooms. Among twenty-three tested mushrooms against A. niger, B. cinerea, F. oxysporum, and G. bidwellii, Schizophyllum commune demonstrated highest inhibition rates and showed 35.7%, 6.5%, 50.4%, and 66.0% of growth inhibition, respectively. To reveal culture conditions enhancing the antifungal potential of Sch. commune, several carbon (lignocellulosic substrates among them) and nitrogen sources and their optimal concentrations were investigated. Presence of 6% mandarin juice production waste (MJPW) and 6% of peptone in nutrient medium promoted antifungal activity of selected mushroom. It was determined that, extracts obtained in the presence of MJPW effectively inhibited the grow of pathogenic fungi. Moreover, the content of phenolic compounds in the extracts obtained from Sch. commune grown on MJPW was several times higher (0.87 ± 0.05 GAE/g to 2.38 ± 0.08 GAE/g) than the extracts obtained from the mushroom grown on the synthetic (glycerol contained) nutrient medium (0.21 ± 0.03 GAE/g to 0.88 ± 0.05 GAE/g). Flavonoid contents in the extracts from Sch. commune varied from 0.58 ± 0.03 to 27.2 ± 0.8 mg QE/g. Identification of phenolic compounds composition in water and ethanol extracts were provided by mass spectrometry analysis. Extracts demonstrate considerable free radical scavenging activities and the IC50 values were generally low for the extracts, ranging from 1.9 mg/ml to 6.7 mg/ml. All the samples displayed a positive correlation between their concentration (0.05-15.0 mg/ml) and DPPH radical scavenging activity. This investigation revealed that Sch. commune mushroom has great potential to be used as a source of antifungal and antioxidant substances.

In-vitro cultural, nutritional, antioxidant and antimicrobial potential of Macrolepiota procera and Amanita caesaria: a rare mushroom from Madhya Pradesh, India under submerged culture condition

Macrolepiota procera and Amanita caesaria are the rarely accepted mushrooms among the society even if both are well known for their therapeutic properties. Present findings are focused on their in-vitro growth performance, colony characteristics, nutritional properties, antioxidant and antimicrobial activity under submerged culture conditions. The mushroom fruit bodies were collected from the different forest divisions of Madhya Pradesh and cultured. Malt extract broth was best suited medium for both Macrolepiota procera and Amanita caesaria. Biochemical studies in the mushroom mycelia grown in malt extract revealed a very good range of phyto-chemicals, which are considered as strong therapeutic agents. In addition, radical scavenging activity in the culture broth was assayed and highest activity was also recorded in malt extract media. Macrolepiota procera exhibited 55.74 % while Amanita caesaria exhibited 61.22 % of free radical scavenging activity. Malt extract medium thus proved to be the best medium for the culturing as well as for the production of antioxidants by both the mushroom species selected. In case of Antioxidant activity boiled water extract proven to be better than methanolic extract.

Streptomyces sp. ADR1, Strain Producing β- and γ-Rubromycin Antibiotics, Isolated from Algerian Sahara Desert

A Gram-positive strain, ADR1, was isolated from soil collected from the Algerian Sahara Desert. The ethyl acetate extract of the fermentation broth showed cytotoxic activity against the PANC-1 cell line (37.1 ± 1.3% viability when applied at a concentration of 100 µg/mL). Fractionation and NMR analysis of two peaks absorbing at 490 nm revealed that they represented β- and γ-rubromycin, anticancer antibiotic compounds. The ADR1 strain contained LL-diaminopimelic acid in the whole-cell hydrolysate, and the partial 16S ribosomal RNA gene sequence (1392 bp, Accession No. KF947515) showed 99% sequence similarity to Streptomyces species. Therefore, the name Streptomyces sp. ADR1 was proposed and deposited in the Wellness Industries Culture Collection (WICC) of the Institute of Bioproduct Development, UTM, Malaysia, under the number (WICC- B86). In a 16 L stirred-tank bioreactor, the stain was adapted to submerged culture conditions and produced rubromycins at a relatively high concentration, with maximums of 24.58 mg/L and 356 mg/L for β- and γ-rubromycins, respectively.

Natural Substrates and Culture Conditions to Produce Pigments from Potential Microbes in Submerged Fermentation

Pigments from bacteria, fungi, yeast, cyanobacteria, and microalgae have been gaining more demand in the food, leather, and textile industries due to their natural origin and effective bioactive functions. Mass production of microbial pigments using inexpensive and ecofriendly agro-industrial residues is gaining more demand in the current research due to their low cost, natural origin, waste utilization, and high pigment stimulating characteristics. A wide range of natural substrates has been employed in submerged fermentation as carbon and nitrogen sources to enhance the pigment production from these microorganisms to obtain the required quantity of pigments. Submerged fermentation is proven to yield more pigment when added with agro-waste residues. Hence, in this review, aspects of potential pigmented microbes such as diversity, natural substrates that stimulate more pigment production from bacteria, fungi, yeast, and a few microalgae under submerged culture conditions, pigment identification, and ecological functions are detailed for the benefit of industrial personnel, researchers, and other entrepreneurs to explore pigmented microbes for multifaceted applications. In addition, some important aspects of microbial pigments are covered herein to disseminate the knowledge.

Transcriptome sequencing reveals altered ciliogenesis under hypoxia in nasal epithelial cells from chronic rhinosinusitis with nasal polyps.

BackgroundHypoxia is considered a key factor in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP). However, the specific mechanism driving polypogenesis under hypoxic conditions is unclear. This study aimed to explore hypoxia‐induced alterations in the transcriptome of human nasal epithelial cells (HNECs) in vitro.MethodsHNECs derived from the tissue of patients with CRSwNP were established as air–liquid interface (ALI) cultures. Confluent cultures were kept submerged or treated with cobalt chloride (CoCl2) to induce hypoxia. Transcriptome analysis was used to identify key mRNAs involved in this process. Real‐time PCR (RT–PCR), Western blotting, and immunofluorescence were used to observe the effects of hypoxia on ciliogenesis.ResultsNumerous genes, biological processes and pathways were altered under submerged culture conditions or after CoCl2 treatment. Analysis of the results under both hypoxic conditions revealed that the transcriptional program responsible for ciliogenesis was significantly impaired. Downregulation of cilia‐related genes and inhibition of ciliated cell differentiation under hypoxia were confirmed by RT–PCR, Western blot and immunofluorescence analyses.ConclusionHypoxia impairs ciliogenesis and ciliary function in HNECs, which might play a role in the pathogenesis of CRSwNP.

Unveiling a Novel Role of Cdc42 in Pyruvate Metabolism Pathway to Mediate Insecticidal Activity of Beauveria bassiana.

The small GTPase Cdc42 acts as a molecular switch essential for cell cycles and polar growth in model yeast, but has not been explored in Beaurveria bassiana, an insect-pathogenic fungus serving as a main source of fungal formulations against arthropod pests. Here, we show the indispensability of Cdc42 for fungal insecticidal activity. Deletion of cdc42 in B. bassiana resulted in a great loss of virulence to Galleria mellonella, a model insect, via normal cuticle infection as well as defects in conidial germination, radial growth, aerial conidiation, and conidial tolerance to heat and UVB irradiation. The deleted mutant’s hyphae formed fewer or more septa and produced unicellular blastospores with disturbed cell cycles under submerged-culture conditions. Transcriptomic analysis revealed differential expression of 746 genes and dysregulation of pyruvate metabolism and related pathways, which were validated by marked changes in intracellular pyruvate content, ATP content, related enzyme activities, and in extracellular beauvericin content and Pr1 protease activity vital for fungal virulence. These findings uncover a novel role for Cdc42 in the pathways of pyruvate metabolism and the pyruvate-involved tricarboxylic acid cycle (TCA cycle) and a linkage of the novel role with its indispensability for the biological control potential of B. bassiana against arthropod pests.

Bioremediation Performance of Sphingomonas melonis and Bacillus muralis on Herbicide Diquot Dipremide-(ethylene-d4)

Bioremediation is a process that utilizes the degradation potential of microorganism to provide a cost-effective and reliable approach for pesticide biodegradation. For this purpose, chosen bacteria Sphingomonas melonis and Bacillus muralis were isolated from an agricultural soil sample. The biodegradation performance of these isolated bacteria at different Diquot Dipremide-(ethylene-d4) (DDE4) herbicide concentrations (250, 500 and 1000 ppm) was investigated under submerged culture conditions. Biodegradation performance of isolated bacteria was monitored with COD, TOC and, BOD5 reduction rates in culture medium at different incubation periods. According to the results; S. melonis has the highest bioremediation capacity for COD removal (91% at 250 ppm). For TOC, B. muralis has the highest removal rate as 82% at 250 ppm. On the other hand, For BOD5 at 250 ppm 85% S. melonis showed the best removal performance. Most effective removal rate at 250 ppm concentrations was obtained as 91% and 88 by S. melonis and B. muralis respectively at the end of the 216th hour for COD. Additionally, the increase in turbidity related with population dynamics at the end of the 216 th hour positively effected the bioremediation parameters included COD, TOC and BOD5 reductions. These results showed that it can be used for effective COD, TOC and BOD5 removal in S. melonis and B. muralis on DDE4 remediation.

Biosorption and Bioleaching of Heavy Metals from Electronic Waste Varied with Microbial Genera

Industrialization and technological advancements have led to the exploitation of natural resources and the production of hazardous wastes, including electronic waste (E-waste). The traditional physical and chemical techniques used to combat E-waste accumulation have inherent drawbacks, such as the production of harmful gases and toxic by-products. These limitations may be prudently addressed by employing green biological methods, such as biosorption and bioleaching. Therefore, this study was aimed at evaluating the biosorption and bioleaching potential of seven microbial cultures using E-waste (printed circuit board (PCB)) as a substrate under submerged culture conditions. The cut pieces of PCB were incubated with seven microbial cultures in liquid broth conditions in three replicates. Atomic absorption spectroscopy (AAS) analysis of the culture biomass and culture filtrates was performed to evaluate and screen the better-performing microbial cultures for biosorption and bioleaching potentials. The best four cultures were further evaluated through SEM, energy-dispersive X-ray spectroscopy (EDX), and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) studies to identify the possible culture that can be utilized for the biological decontamination of E-waste. The study revealed the highest and differential ability of Pleurotus florida and Pseudomonas spp. for biosorption and bioleaching of copper and iron. This can be attributed to bio-catalysis by the laccase enzyme. For both P. florida and Pseudomonas spp. on the 20th day of incubation, laccase exhibited higher specific activity (6.98 U/mg and 5.98 U/mg, respectively) than other microbial cultures. The biomass loaded with Cu2+ and Fe2+ ions after biosorption was used for the desorption process for recovery. The test cultures exhibited variable copper recovery efficiencies varying between 10.5 and 18.0%. Protein characterization through SDS-PAGE of four promising microbial cultures exhibited a higher number of bands in E-waste as compared with microbial cultures without E-waste. The surface topography studies of the E-waste substrate showed etching, as well as deposition of vegetative and spore cells on the surfaces of PCB cards. The EDX studies of the E-waste showed decreases in metal element content (% wt/% atom basis) on microbial treatment from the respective initial concentrations present in non-treated samples, which established the bioleaching phenomenon. Therefore, these microbial cultures can be utilized to develop a biological remediation method to manage E-waste.

Optimization of Exopolysaccharide Production by Soil Actinobacterium Streptomyces plicatus under Submerged Culture Conditions

Extracellular polymeric substances (EPSs) are ecologically friendly natural polymers produced by microorganisms in the surrounding media. Due to their varied chemical composition, exopolysaccharides are widely used in a variety of applications, including food, pharmaceuticals, and medical applications. In this work, thirty-six isolates of Actinobacteria isolated on starch nitrate medium from various locations of Egyptian soils were assessed for exopolysaccharide (EPS) synthesis. The isolated bacterium that produced the most EPS was Actinobacterium 10 (Streptomyces plicatus). Several culture and environmental parameters were investigated during the microbial growth in submerged culture to enhance bacterial growth and EPS production. The optimal crude EPS generation of 8.62 g/l was achieved after 7 days of incubation at 20 g/l starch concentration, at 35 °C and pH 7, under shaking at 120 rpm, with the most significant impacts. The findings of this study pave the door to produce large quantities of EPS from soil Actinobacteria for food and medicinal purposes.

Lignocellulosic Ezymes of Basidial Fungi-Isolated from Different Ecological Niches of Georgia

Great interest in basidiomycetes for targeted technological treatment of agro-industrial plant substrates are conditioned by their ability to produce lignocellulosic enzymes. Consisting of 29 soil-climatic zones, Georgia (South Caucasus area) represents a unique place for the isolation of microorganisms. In order to study the biochemistry and physiology of wood-degrading basidiomycetes, samples of wood-degrading basidiomycetes were collected from different taxonomic niches of Georgia. 45 strains were obtained as pure cultures and 32 ones – identified. Producers of lignocellulosic enzymes were revealed among test fungi under solid-state and submerged cultivation conditions. Pleurous ostreatus GV10, Pleurotus drynus IN 11 and Fomes fomentarius GK33 were found to be the best producers of cellulosic enzymes using orange and mandarin peels, wheat and Potato straw, wheat bran as substrates, and Ganoderma lucidum GB03 – the best producer of laccase during cultivation on orange and mandarin peels waste. The influence of lignocellulose on the accumulation of the enzymes laccase, xylanase and Filter paper assay was studied.

Lignocellulosic Ezymes of Basidial Fungi-Isolated from Different Ecological Niches of Georgia

Great interest in basidiomycetes for targeted technological treatment of agro-industrial plant substrates are conditioned by their ability to produce lignocellulosic enzymes. Consisting of 29 soil-climatic zones, Georgia (South Caucasus area) represents a unique place for the isolation of microorganisms. In order to study the biochemistry and physiology of wood-degrading basidiomycetes, samples of wood-degrading basidiomycetes were collected from different taxonomic niches of Georgia. 45 strains were obtained as pure cultures and 32 ones – identified. Producers of lignocellulosic enzymes were revealed among test fungi under solid-state and submerged cultivation conditions. Pleurous ostreatus GV10, Pleurotus drynus IN 11 and Fomes fomentarius GK33 were found to be the best producers of cellulosic enzymes using orange and mandarin peels, wheat and Potato straw, wheat bran as substrates, and Ganoderma lucidum GB03 – the best producer of laccase during cultivation on orange and mandarin peels waste. The influence of lignocellulose on the accumulation of the enzymes laccase, xylanase and Filter paper assay was studied.