Yeast Glucose Research Articles

Utilization of the sugar fraction from Arabica coffee pulp as a carbon source for bacteria producing cellulose and cytotoxicity with human keratinocyte

Coffee pulp (CP), a by-product of coffee production, is an underutilized resource with significant potential value. CP contains monosaccharides that can serve as an ideal carbon source for bacterial cultivation, enabling the production of value-added components such as medical-grade cellulose. Herein, we extracted the sugar fraction from Arabica CP and used it as a supplement in a growing media of a bacteria cellulose (BC), Komagataeibacter nataicola. The BC was then characterized and tested for cytotoxicity. The CP sugar fraction yielded approximately 7% (w/w) and contained glucose at 4.52 mg/g extract and fructose at 7.34 mg/g extract. Supplementing the sugar fraction at different concentrations (0.1, 0.3, 0.5, 0.7, and 1 g/10 mL) in sterilized glucose yeast extract broth, the highest yield of cellulose (0.0020 g) occurred at 0.3 g/10 mL. It possessed similar physicochemical attributes to the BC using glucose, with some notable improvements in fine structure and arrangement of the functional groups. In cytotoxicity assessments on HaCaT keratinocyte cells, bacterial cellulose concentrations of 2–1000 µg/mL exhibited viability of ≥ 80%. However, higher concentrations were toxic. This research innovatively uses coffee pulp for bacterial cellulose, aligning with the principles of a bio-circular economy that focuses on sustainable biomass utilization.

Molecular Characterization of Multi-Drug Resistant Fungal Isolates Obtained from Raw Cow Milk in Bowen University, Nigeria

Cow milk is a highly nutritious food but many factors predispose it to microbial contamination. There is paucity of information on antifungal-resistant pathogens. Hence the study investigated the fungi from fresh cow milk samples and their resistance to some antifungals. Twenty-seven (27) fungi were isolated from forty-three (n=43) milk samples on PDA (Potato dextrose agar) media, re-cultured in glucose yeast extract broth, and incubated for 24 hours at 25°C. Taxonomic characterization on the isolates was done using photomicrography. Percentage occurrence of the isolates was determined. Molecular characterization was carried out on some isolates which were 100% resistant to antifungals; ketoconazole, amphotericin B, and clotrimazole using ITS1 and ITS4 primers. Isolate sequences were subjected to BLAST analysis and compared with representatives in GenBank. Kruskal-Wallis and Mann-Whitney Tests were used to analyze the data. Phylogenetic analysis and morphological characterization identified isolates as Rhodotorula paludigena, Candida sp and Candida tropicalis which had occurrence of 31.8%, 31.8% and 36.6% respectively. Level of resistance to ketoconazole (100%) and amphotericin B (92%) was significantly higher than clotrimazole (59%) (p< 0.05), while between ketoconazole and amphotericin B, there was no significant (p> 0.05) difference. Unprocessed raw milk is a potential source of drug-resistant pathogenic fungi. Pasteurization of raw milk is highly encouraged before consumption.

Bioprospecting of Lactobacillus sp. Starter Culture from Colostrum Breast Milk for Probiotic Milk Production from Soybeans

Lactobacillus sp. is a bacterium that naturally exists in various environments, including in breast milk colostrum. This bacterium belongs to a group of lactic acid bacteria that produce lactic acid as the main product of sugar fermentation so that it has probiotic properties that also play a role in the fermentation process. This study aims to produce probiotic milk using Lactobacillus sp isolates from breast milk colostrum with soybean (Glycine max (L.) Merril.) as the base material and then test the total lactic acid content, pH value, reducing sugar and the number of lactic acid bacteria. The production of soybean fermented milk is based on the analysis of total lactic acid content by acid-base titration method with 0.1 N NaOH standard solution, pH value by using universal pH meter, reducing sugar test by spectrophotometric method of Nelson-Somogyi and the number of lactic acid bacteria by using Glucose Yeast Pepton Agar (GYPA) medium added with CaCO3 then calculated by using Standard Plate Count (SPC) method with TPC value (Total Plate Number) is 2.3. 1012 colonies/ml, 2.5.1012 colonies/ml, 4.5.1014 colonies/ml, 4.1.1014 colonies/ml. From the results of the study it is known that Lactobacillus sp isolates from breast milk colostrum fluid can ferment soybean milk (Glycine max (L.) Merril.)

Elucidating the physiological and molecular characteristics of bacterial blight incitant Xanthomonas auxonopodis pv. punicae; a life threatening phytopathogen of pomegranate (Punica granatum. L) and assessment of H2O2 accumulation during host-pathogen interaction

Bacterial blight of pomegranate caused by Xanthomonas auxonopodis pv.punicae (Xap) threaten the existence of a group of farmers for the past few decades who rely on pomegranate cultivation for their livelihood since it will cause huge yield loss. The primary focus of this study was to conduct a thorough analysis of the characterization of this blight incitant Xap. Physiological, biochemical, and molecular characteristics of six phytopathogenic strains of Xap, designated as PBF1 (PBF: Pomegranate Blight Fruit), PBF2, PBF3, PBF4, PBF5, and PBF6, isolated from the infected fruits were examined. Bacterial colonies were featured as gram-negative, yellow-pigmented circular with a glistening appearance. An attempt to determine the best culture medium, favouring bacterial proliferation was successfully done with four distinct medium, Nutrient Glucose Agar (NGA), Nutrient sucrose Agar (NSA), Yeast Dextrose Calcium Carbonate Agar (YDCA) and Yeast Glucose Calcium Carbonate Agar (YGCA) and comparatively, significant growth was found in NGA (66.66%) followed by YDCA (33%). According to the antibiotic susceptibility results, both ampicillin and streptomycin were determined as potentially effective drugs in preventing the proliferation of Xap (P 0.05). The reactive oxygen species-mediated plant immune response during host-pathogen interaction was confirmed by accessing the presence of H2O2 accumulation in infected leaves via 3,3 - diaminobenzidine (DAB) -staining technique. Bacterial isolates from this study were confirmed by two universal constitutive genes such as gyrB and 16S rRNA. From the BLAST analysis, the isolates were identified as Xap with base pair lengths of 1408bp, 1180bp, and 1159bp, which correspond to PBF1, PBF2, and PBF3, respectively. A neighbor-joining phylogenetic tree study explaining a strong phylogenetic relationship between the query sequence and closely related bacterial species.

Growth of Bacillus spp. Isolated From Nipah Worm Intestine (Namalycastis rhodochorde) With Different Combination of pH and Salinity

Bacillus spp. (NrLtF1, NrLtF5, and NrLtG2) isolated from the digestive tract of the Nypa palm worm (Namalycastis rhodochorde) were assumed to have growth characteristics according to the habitat conditions of the nypa worm. Nypa worms live in estuary environments that are affected by seawater intrusion. Salinity and pH are two environmental factors affecting gastrointestinal isolates' growth from nypa palm worms. This study aimed to determine the effect of pH and salinity on the media on growth patterns and determine the optimum combination of pH and salinity for Bacillus spp. The study was conducted using a spectrophotometry method using a microplate reader with Glucose Yeast Peptone (GYP) as a medium for bacterial growth. The medium's pH and salinity values were adjusted by adding 5M NaOH and 5M HCl to obtain pH values of 4, 5, 6, and 7, respectively. Addition of NaCl to the growing medium to get salinity values of 5%, 10%, and 15%. Optimization was determined by incubation at a density of 595 nm at a temperature of 31oC for 24 hours. The results showed that Bacillus spp. could grow well at pH 6 with a salinity value of 15%, pH 6 with a salinity value of 10%, and pH 6 with a salinity value of 5% based on contour plot design. The Optimum growth of Bacillus spp. with pH and salinity expects to be a reference for developing feed products based on indigenous nypa palm worms.

Microbiological and Physico-Chemical Characteristics of Black Tea Kombucha Fermented with a New Zealand Starter Culture.

Kombucha is a popular sparkling sugared tea, fermented by a symbiotic culture of acetic acid bacteria (AAB) and yeast. The demand for kombucha continues to increase worldwide, mainly due to its perceived health benefits and appealing sensory properties. This study isolated and characterised the dominant AAB and yeast from a starter culture and kombucha broth after 0, 1, 3, 5, 7, 9, 11, and 14 days of fermentation at ambient temperature (22 °C). Yeast and AAB were isolated from the Kombucha samples using glucose yeast extract mannitol ethanol acetic acid (GYMEA) and yeast extract glucose chloramphenicol (YGC) media, respectively. The phenotypic and taxonomic identification of AAB and yeast were determined by morphological and biochemical characterisation, followed by a sequence analysis of the ribosomal RNA gene (16S rRNA for AAB and ITS for yeast). The changes in the microbial composition were associated with variations in the physico-chemical characteristics of kombucha tea, such as pH, titratable acidity, and total soluble solids (TSS). During fermentation, the acidity increased and the TSS decreased. The yield, moisture content, and water activity of the cellulosic pellicles which had developed at the end of fermentation were attributed to the presence of AAB. The dominant AAB species in the cellulosic pellicles and kombucha broth were identified as Komagataeibacter rhaeticus. The yeast isolates belonged to Debaryomyces prosopidis and Zygosaccharomyces lentus.

Metabolites Alteration and Antioxidant Activity of Gracilaria verrucosa After Fermentation Using Aureobasidium melanogenum MTGK.31

Gracilaria verrucosa is a red seaweed that has been widely utilized in the food andpharmaceutical industries due to its biological properties. The utilization of biologicalagents in obtaining certain bioactive compounds would confront unavoidable issues,particularly its bioactive sustainability. Hence, microbial fermentation has been reported as a practical approach to maintaining bioactive production and boosting its properties. Our study aimed to evaluate the potential of marine yeast Aureobasidium melanogenum MTGK.31 as a fermenting agent for G. verrucosa and characterize the seaweed metabolite profile and antioxidant activity after fermentation. The seaweed was fermented using A. melanogenum MTGK.31 in a medium consisting of yeast extract, peptone, and glucose. The fermentation was done for 24, 48, and 72 hours. Total plate count and pH were measured after each fermentation period. The primary and secondary metabolites of G. verrucosa in each fermentation were observed. Antioxidant assay using the 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) method was conducted, followed by total phenolic content using the Folin-Ciocalteu method. It was highlighted that yeast colony increased during the fermentation, while the pH level was decreasing. We found that the fermentation not only boosted some elements in primary metabolites, but also increased G. verrucosa bioactive groups. After 72 hours of fermentation, the G. verrucosa percent radical scavenging activity (%RSA) increased more than two times compared to the fresh G. verrucosa with a %RSA value of 16.09±6.57. Nevertheless, the highest total phenolic content of 5.62±0.00028 mg GAE/g extract was shown by G. verrucosa after 48 hours of fermentation.

Metabolites Alteration and Antioxidant Activity of Gracilaria verrucosa After Fermentation Using Aureobasidium melanogenum MTGK.31

Gracilaria verrucosa is a red seaweed that has been widely utilized in the food and pharmaceutical industries due to its biological properties. The utilization of biological agents in obtaining certain bioactive compounds would confront unavoidable issues, particularly its bioactive sustainability. Hence, microbial fermentation has been reported as a practical approach to maintaining bioactive production and boosting its properties. Our study aimed to evaluate the potential of marine yeast Aureobasidium melanogenum MTGK.31 as a fermenting agent for G. verrucosa and characterize the seaweed metabolite profile and antioxidant activity after fermentation. The seaweed was fermented using A. melanogenum MTGK.31 in a medium consisting of yeast extract, peptone, and glucose. The fermentation was done for 24, 48, and 72 hours. Total plate count and pH were measured after each fermentation period. The primary and secondary metabolites of G. verrucosa in each fermentation were observed. Antioxidant assay using the 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) method was conducted, followed by total phenolic content using the Folin-Ciocalteu method. It was highlighted that yeast colony increased during the fermentation, while the pH level was decreasing. We found that the fermentation not only boosted some elements in primary metabolites, but also increased G. verrucosa bioactive groups. After 72 hours of fermentation, the G. verrucosa percent radical scavenging activity (%RSA) increased more than two times compared to the fresh G. verrucosa with a %RSA value of 16.09±6.57. Nevertheless, the highest total phenolic content of 5.62±0.00028 mg GAE/g extract was shown by G. verrucosa after 48 hours of fermentation.

Biosynthesis and Characterization of Silver Nanoparticles Using Tribulus terrestris Seeds: Revealed Promising Antidiabetic Potentials.

Green synthesis is the most effective and environmentally friendly way to produce nanoparticles. The present research aimed at the biosynthesizing of silver nanoparticles (AgNPs) using Tribulus terrestris seed extract as the reducing and stabilizing agent and investigating their anti-diabetic properties. Fourier transformation infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-Vis spectroscopy were used to analyze the synthesized silver nanoparticles from Tribulus terrestris (TT-AgNPs). The spectroscopic characterization revealed a surface Plasmon resonance band at 380 nm, which verified the development of TT-AgNPs. The transmittance peaks were observed at 596, 1450, 1631, 2856, 2921, and 3422 cm-1 through the FTIR spectrophotometer. The XRD spectrum showed four distinct diffraction peaks in the 2θ range at 20° to 60°. Intense peaks were at 26.32°, 30.70°, 44.70°, 56.07°, 53.75°, 66.28°, and 75.32°. The SEM analysis revealed that the prepared TT-AgNPs were clustered loosely with a smooth and spherical structure and were of relatively uniform size. The in vitro antidiabetic potential of TT-AgNPs was assessed by using glucose yeast uptake, glucose adsorption, and alpha-amylase assays. TT-AgNPs showed the highest activity (78.45 ± 0.84%) of glucose uptake by yeast at 80 µg/mL. In the glucose adsorption assay, the highest activity of TT-AgNPs was 10.40 ± 0.52% at 30 mM, while in the alpha-amylase assay, TT-AgNPs exhibited the maximum activity of 75.68 ± 0.11% at 100 µg/mL. The results indicate a substantial anti-diabetic effect of the TT-AgNPs. Furthermore, the in vivo antidiabetic study was performed on TT-AgNPs in streptozotocin-induced diabetic mice. After receiving TT-AgNPs treatment for 30 days, the mice were sacrificed for biochemical and histological analyses of pancreatic and liver samples, which demonstrated a good improvement when compared to the control group. Mice treated with TT-AgNPs showed a significant drop in blood sugar levels, showing that the biosynthesized TT-AgNPs have effective anti-diabetic properties.

Screening of Syzygium cumini (L.) Seed Ethanol and Hexane Extracts for Phytochemicals, Antioxidant, and Anti-Diabetic Efficacy: An In-vitro Study

Many medicinal plant extracts have been known since ancient times to possess antioxidant activity to scavenge free radicals and anti-diabetic activity to control diabetes. In this study, seeds of Syzygium cumini were extracted in ethanol and hexane solvents. Primary and secondary metabolites were quantified. DPPH assay, nitric oxide scavenging (NOS) assay and ferric reducing antioxidant power (FRAP) assays were employed to study antioxidant activity. α-amylase inhibitory assay (AAI), yeast glucose uptake assay (YGU) and haemoglobin glycosylation inhibitory (HGI) assays were adapted to determine anti-diabetic properties. The results from the assays and the IC50 values (18.35 µg/ml in DPPH, 943.8 µg/ml in NOS, 871.3 µg/ml in FRAP, 886 µg/ml in AAI, 764 µg/ml in YGU, and 1495.1 µg/ml in HGI assay) indicate that S. cumini seed ethanol extract has higher antioxidant and anti-diabetic efficiency than the hexane extract. Our findings suggest that the rich phytochemical content of S. cumini seeds and its good antioxidant and anti-diabetic activity may be responsible for its popularity and wide traditional use and can be exploited to develop antioxidant and anti-diabetic drugs.

Plant Growth-promoting Ability and Pathogen Inhibitory Effect of Actinomycetes Isolated from Fecal Pellets of the Giant Millipede Thyropygus resimus (Diplopoda)

The microbial properties of millipede fecal pellets have been studied mainly in Glomerida (pill millipedes), and much less in the significant majority of other millipede groups. Therefore, the present study examined actinomycetes isolated from the fecal pellets of the non-glomerid giant millipede Thyropygus resimus Attems, 1938 (Spirostreptida) to (1) test their plant growth-promoting ability, and (2) evaluate their potential to control and inhibit plant pathogenic microorganisms. Millipedes were collected from Phu Kum Khao, Kalasin Province, Thailand. A total of 59 actinomycete isolates were obtained and identified as belonging to the genus Streptomyces using 16S rRNA sequencing. The plant growth-promoting properties of the isolates were tested by screening four characteristics: nitrogen fixation, phosphate solubility, siderophore production, and indole-3-acetic acid (IAA) production. A nitrogen-fixation test on nitrogen-free solid malate media (NFM) showed that 54 isolates were capable of fixing nitrogen. Phosphate solubility was tested on double-layered glucose yeast extract agar (GYA) medium containing tricalcium phosphate. This showed that 42 isolates formed a clear zone around the colonies due to phosphate dissolution. Siderophore production was tested on chrome azurol sulfate (CAS) agar. This showed that 55 isolates could grow on this medium and form clear yellow to orange zones around their colonies. IAA production tests revealed that 41 isolates could produce IAA. Based on the combined results of these four tests, eight of the 59 isolates were the most effective in promoting plant growth: KLS-AC04, KLD-AC01, KLD-AC02-1, KLD-AC08, KLD-AC09, KLD-AC16, KLD-AC29-1, and KLD-AC30. Seventeen isolates inhibited the growth of Xanthomonas oryzae pv. oryzae, the causal agent of bacterial leaf blight disease in rice, more effectively than rifampicin (100 ppm), with isolate KLS-AC02-1-1 being the most effective (inhibition zone, 58.25 mm in diameter). Therefore, these isolates can be used for growth promotion and rice disease control in the future.

Toxicogenic fungal profile, Ochratoxin A exposure and cancer risk characterization through maize (Zea mays) consumed by different age populations in the Volta region of Ghana

Maize (Zea mays) is an important staple food crop for the majority of Ghanaians. Maize is mostly contaminated by fungal species and particularly mycotoxins. This work aimed to identify and quantify the incidence of fungal infection and exposure to Ochratoxin A (OTA) as well as the health risk characterization in different age populations due to maize consumption in the Volta region. Maize samples were plated on Dichloran Rose Bengal Chloramphenicol (DRBC) agar, and Oxytetracycline Glucose Yeast Extract (OGYE) agar. All media were prepared in accordance with the manufacturers' instructions. The plates were incubated at 28±2°C for 5-7 days. High-Performance Liquid Chromatography connected to a fluorescence detector (HPLC-FLD) was used to analyze the ochratoxin A (OTA) levels in maize. Cancer risk assessments were also conducted using models prescribed by the Joint FAO/WHO Expert Committee on Additives (JECFA). The maize samples collected from the Volta region contained fungal population between the range of 3.08-4.58 log10CFU/g. Eight (8) genera were recorded belonging to Aspergillus, Trichoderma, Penicillium, Fusarium, Saccharomyces, Mucor, Rhodotorula and Rhizopus. The species diversity includes A. flavus, A. niger, T. harzianum, P. verrucosum, F. oxysporum, Yeast, F. verticillioides, Rhodotorulla sp, A. fumigatus, R. stolonifer, M. racemosus species. Additionally, the ochratoxins level contained in the samples were very noteworthy and ranged from 1.22 to 28.17 μg/kg. Cancer risk assessments of OTA produced outcomes also ranged between 2.15 and 524.54ng/kgbw/day, 0.03-8.31, 0.0323, and 0.07-16.94 for cases/100,000 person/yr for Estimated Daily Intake (EDI), Margin of Exposure (MOE), Average Potency, and Cancer Risks respectively for all age categories investigated. There was very high mycoflora load on the maize sampled from the Volta region, likewise the range of mycotoxins present in the maize grains, suggesting the potential to pose some adverse health effects with the populace of the Volta region.

Effects of Sorghum Grain and Wort Composition on Dry Grind Fermentation Performance: A Model for Baijiu Production

Sorghum grain is the principal raw material for Baijiu production, but the effects of grain and wort composition on fermentation performance are unclear. Ethanol production at laboratory scale using grains of 11 commercial sorghum cultivars from a field trial was investigated using dry grind fermentation. Initial wort glucose content was 141–150 g/L and fermentability (glucose-to-ethanol conversion rate) was 87–90%. Ethanol production rate among sorghum genotypes ranged from 1.18 to 2.04 mL of ethanol per litre wort per hour of fermentation. The cultivars were categorised into four groups according to a fermentation endpoint of 60–69 h, 70–79 h, 80–89 h and &gt;90 h. All but one of the sorghums produced a final ethanol content of 9.47–9.76% v/v. Cultivars with high-starch and low-protein grains were the most suitable for fermentation due to the high final ethanol content and fermentability achieved. Initial wort glucose content and yeast assimilable nitrogen content were not correlated with grain starch content, protein content, ethanol content, fermentability, ethanol production rate or glucose consumption rate. Knowledge of the effects of sorghum grain quality on fermentation performance can pave the way for further research to optimise solid-state fermentation for Baijiu production.

Bioactivity Profiling and Untargeted Metabolomics of Microbiota Associated with Mesopelagic Jellyfish Periphylla Periphylla

The marine mesopelagic zone extends from water depths of 200 m to 1000 m and is home to a vast number and diversity of species. It is one of the least understood regions of the marine environment with untapped resources of pharmaceutical relevance. The mesopelagic jellyfish Periphylla periphylla is a well-known and widely distributed species in the mesopelagic zone; however, the diversity or the pharmaceutical potential of its cultivable microbiota has not been explored. In this study, we isolated microorganisms associated with the inner and outer umbrella of P. periphylla collected in Irminger Sea by a culture-dependent approach, and profiled their chemical composition and biological activities. Sixteen mostly gram-negative bacterial isolates were selected and subjected to an OSMAC cultivation regime approach using liquid and solid marine broth (MB) and glucose-yeast-malt (GYM) media. Their ethyl acetate (EtOAc) extracts were assessed for cytotoxicity and antimicrobial activity against fish and human pathogens. All, except one extract, displayed diverse levels of antimicrobial activities. Based on low IC50 values, four most bioactive gram-negative strains; Polaribacter sp. SU124, Shewanella sp. SU126, Psychrobacter sp. SU143 and Psychrobacter sp. SU137, were prioritized for an in-depth comparative and untargeted metabolomics analysis using feature-based molecular networking. Various chemical classes such as diketopiperazines, polyhydroxybutyrates (PHBs), bile acids and other lipids were putatively annotated, highlighting the biotechnological potential in P. periphylla-associated microbiota as well as gram-negative bacteria. This is the first study providing an insight into the cultivable bacterial community associated with the mesopelagic jellyfish P. periphylla and, indeed, the first to mine the metabolome and antimicrobial activities of these microorganisms.

Nanopore Direct RNA Sequencing of Monosome- and Polysome-Bound RNA.

Polysome fractionation makes use of density gradients and ultracentrifugation to separate transcripts based on their specific number of bound ribosomes, and can be combined with downstream analysis such as cDNA-seq (commonly known as RNA-seq), microarray analysis, RT-qPCR, or Northern blotting. Here, we describe the application of Nanopore direct RNA sequencing to quantify monosome- and polysome-bound full-length transcripts after polysome fractionation, RNA cleanup, and size selection, using the yeast glucose stress response as an example use case.

Nitrogen Sources Affect the Long-Chain Polyunsaturated Fatty Acids Content in Thraustochytrium sp. RT2316-16.

The psychrophilic marine microorganism Thraustochytrium sp. RT2316-16 can produce carotenoids as well as lipids containing the omega-3 polyunsaturated fatty acids (PUFA) eicosapentaenoic acid and docosahexaenoic acid. This work reports on the effects of the composition of the culture medium, including certain amino acids, on growth and lipid synthesis by RT2316-16. Compared with the culture on glutamate, the use of lysine, alanine, or serine, increased the content of the omega-3 PUFA in total lipids. In the media that contained yeast extract, glutamate, and glucose, lipid accumulation occurred when organic ammonium was exhausted earlier than glucose. In contrast, lipid mobilization was promoted if glucose was exhausted while organic ammonium (supplied by yeast extract and glutamate) remained in the medium. The total content of carotenoids in the lipid-free biomass decreased during the first 12 to 24 h of culture, simultaneously with a decrease in the total lipid content of the biomass. The experimental data suggested a possible interrelationship between the metabolism of carotenoids and lipids. A high content of omega-3 PUFA in the total lipids could be obtained by growing the thraustochytrid in a medium with a low glucose concentration (6 g L-1) and a high concentration of organic nitrogen (yeast extract 12 g L-1; glutamate 1.06 g L-1), after glucose was exhausted. These observations may guide the development of a strategy to enhance omega-3 PUFA in the biomass.

Bioconversion of sugarcane molasses and waste glycerol on single cell oils for biodiesel by the red yeast Rhodotorula glutinis R4 from Antarctica

• R. glutinis R4 produce singe cell oil (SCO) from cane molasses and waste glycerol. • The fatty acids composition of SCO from R4 is suitable for biodiesel production. • SCO from R. glutinis R4 were transformed into biodiesel with a 90% efficiency. • Biodiesel derived from SCO of R. glutinis R4 satisfied international fuel standards. In the context of the global energy crisis and the constant demand for biofuels, this work explored the biodiesel production from single-cell oils (SCO) produced by the Antarctic oleaginous yeast Rhodotorula glutinis R4 from low-cost local agro-industrial by-products (sugarcane molasses and waste glycerol). The lipid accumulation reached 46.8% and 40.7% at 120 h of culture using glycerol and molasses, respectively, which correspond to 5.72 and 8.68 g L -1 of final lipid concentration. R. glutinis R4 yielded 0.172 and 0.185 gram of lipids per gram of substrate consumed grown in molasses or glycerol medium, respectively. These amounts being higher than the ones obtained in glucose medium (0.126 g g -1 ). At 120 h of culture, lipid volumetric productivities were 0.048 and 0.072 g L −1 h −1 using glycerol and molasses, respectively, and 0.043 g L −1 h −1 in the glucose yeast extract (GYM) medium. Oleic acid is the predominant fatty acid in the oils from R. glutinis R4, reaching 67.5% with molasses, thus indicating that it is adequate for biodiesel synthesis. This is the first study where SCO produced by R. glutinis R4 were converted into biodiesel by acid transesterification with an efficiency above 90%. The biodiesel produced by R. glutinis R4 grown on culture media containing molasses or waste glycerol is fully compliant with the international standards for biodiesel. SCO obtained from R. glutinis R4 using molasses and waste-glycerol can be effectively used as sources of triacylglycerols for biodiesel production.

Bioactive Alkaloids from the Marine-Derived Fungus Metarhizium sp. P2100.

The Metarhizium fungal species are considered the prolific producers of bioactive secondary metabolites with a variety of chemical structures. In this study, the biosynthetic potential of marine-derived fungus Metarhizium sp. P2100 to produce bioactive alkaloids was explored by using the one strain many compounds (OSMAC) strategy. From the rice solid medium (mixed with glucose peptone and yeast broth (GPY)), wheat solid medium (mixed with Czapek) and GPY liquid medium, one rare N-butenone spiroquinazoline alkaloid, N-butenonelapatin A (1), together with nine known compounds (2-10), were isolated and identified. Their structures were elucidated by analysis of the comprehensive spectroscopic data, including 1D and 2D NMR and HRESIMS, and the absolute configuration of 1 was determined by a single-crystal X-ray crystallographic experiment. N-butenonelapatin A (1) represents the first example of N-butenone spiroquinazoline with a rare α, β-unsaturated ketone side chain in the family of spiroquinazoline alkaloids. Compound 4 displayed antibacterial activity against Vibrio vulnificus MCCC E1758 with a minimum inhibitory concentration (MIC) value of 6.25 µg/mL. Compound 7 exhibited antibacterial activities against three aquatic pathogenic bacteria, including V. vulnificus MCCC E1758, V. rotiferianus MCCC E385 and V. campbellii MCCC E333 with the MIC values of 12.5, 12.5 and 6.25 μg/mL, respectively. Compounds 3 and 6 demonstrated anti-inflammatory activity against NO production induced by lipopolysaccharide (LPS) with the IC50 values of 37.08 and 37.48 μM, respectively. In addition, compound 1 showed weak inhibitory activity against the proliferation of tumor cell lines A-375 and HCT 116. These findings further demonstrated that fungi of the Metarhizium species harbor great potentials in the synthesis of a variety of bioactive alkaloids.

Evaluation of functional and bioactive properties of crude gill extract of Tor putitora using different assays

SummaryFor centuries, natural products isolated from animals, plants and microbes have been the centre of attention for the world's scientific community for their role in eradicating and reducing many diseases. The present research work is also performed on the crude gill extract of Tor putitora named TPG‐Ex to analyse its various functional and bioactive properties. A total of five different biological assays were performed. Two assays performed were the free radical scavenging assays having other free radical generators such as DPPH and H2O2. Different concentrations of extract were used in both assays. The maximum scavenging ability in the Antioxidant DPPH assay was 59.42% at 50 μL. In the H2O2 radical scavenging assay, the maximum scavenging ability of TPG‐Ex recorded was 55.46% at a concentration of 50 μL. The antiangiogenic potential of the TPG‐Ex CAM assay was assessed, which also showed maximum inhibition of neovascularisation at a concentration of 80 μL. The antidiabetic potential of TPG‐Ex was also revealed after processing the extract through glucose uptake by yeast cells assay and glucose adsorption assay. TPG‐Ex indicated maximum glucose uptake at a concentration of 20 μg of 56.61%.

Optimization of culture conditions for vegetative growth of an indigenous strain of Lentinus sajor-caju (Fr.) Fr.

In this manuscript the results of the investigations undertaken on the impact of media composition, temperature, pH, incubation period and light and dark conditions on the vegetative growth of local strain of Lentinus sajor caju (Fr.) Fr., an edible lignicolous mushroom is presented. The mushroom mycelium gave best mycelia growth on Malt Yeast Extract Agar solid medium while from amongst the liquid media used best growth of mushroom mycelium was achieved on Yeast Glucose liquid medium. Optimum temperature of 33 ℃, incubation period of 11 days, pH range from 4.0-5.0 and dark condition favoured the best mycelia growth.