Fungi-derived natural antioxidants.

In humans, exogenous antioxidants aid the endogenous antioxidant system to detoxify excess ROS generated during oxidative stress, thereby protecting the body against various diseases and stressful conditions. The majority of natural antioxidants available on the consumer market are plant-based; however, fungi are being recognized as alternative sources of various natural antioxidants such as polysaccharides, pigments, peptides, sterols, phenolics, alkaloids, and flavonoids. In addition, some exogenous antioxidants are exclusively found in fungi. Fungi-derived antioxidants exhibit scavenging activities against DPPH, ABTS, hydroxyl, superoxide, hydrogen peroxide, and nitric oxide radicals in vitro. Furthermore, in vivo models, application of fungal-derived antioxidants increase the level of various antioxidant enzymes, such as catalases, superoxide dismutases, and glutathione peroxidases, and reduce the level of malondialdehyde. Therefore, fungi-derived antioxidants have potential to be used in the food, cosmetic, and pharmaceutical industries. This review summarizes the antioxidant potential of different fungi (mushrooms, yeasts, and molds)-derived natural compounds such as polysaccharides, pigments, peptides, ergothioneine, ergosterol, phenolics, alkaloids, etc.

Exopolysaccharide of Anoxybacillus pushchinoensis G11 has antitumor and antibiofilm activities.

Exopolysaccharides (EPS/EPSs) possess several various applications in the food and pharmaceutical industries. This study was performed to investigate the biological (antibiofilm and antitumor), rheological (temperature, shear rate, and density) and chemical (solubility, carbohydrate and protein content, composition, molecular weight, functional group analysis, thermal analysis, X-ray diffraction pattern and scanning electron microscopy) properties of the EPS, which was purified from the locally isolated thermophilic bacterium Anoxybacillus pushchinoensis G11 (MN720646). EPS was found to have antibiofilm and antitumor [lung (A-549) and colon (Caco-2 and HT-29) cancer] activities. The viscosity of EPS showing Newtonian flow was temperature dependent. As chemical properties, the EPS was found to be a heteropolysaccharide containing arabinose (57%), fructose (26%), glucose (12%), and galactose (5%). EPS contained 93% carbohydrates and 1.08% protein. The molecular weight of EPS was determined as 75.5 kDa. The FTIR analysis confirmed the presence of sulfate ester (band at 1217 cm-1), an indication of the antitumor effect. The EPS was semi-crystalline. It could maintain 36% of its weight at 800 °C and crystallization and melting temperatures were 221 and 255.6 °C. This is the first report on the EPS production potential and the biological activity of A. pushchinoensis.

Waste frying oil hydrolysis and lipase production by cold-adapted Pseudomonas yamanorum LP2 under non-sterile culture conditions.

Non-sterile culture technique is currently used in some microbial processes. However, there is no study on the use of this technique in the production of microbial lipases and hydrolysis of waste frying oils. This study was conducted to hydrolyse waste frying oils and produce lipase under non-sterile culture conditions using locally isolated cold-adapted bacteria. Of 75 bacterial isolates, the psychrotolerant Pseudomonas yamanorum LP2 (Genbank number: KU711080) was determined to have the highest lipase activity. It was found that a combination of restricted nutrient availability, low temperature and high inoculum volume prevented microbial contaminants under non-sterile conditions. The most favourable parameters for lipase production under both sterile and non-sterile conditions were 15°C temperature, pH 8, 30 mL/L inoculum volume, 40 mL/L waste frying oil concentration, 10 mL/L Tween-80 and 72 h incubation time. The maximum lipase activities in sterile and non-sterile media were determined as 93.3 and 96.8 U/L, respectively. The present process designed for enzyme production and waste oil hydrolysis can reduce the cost of cultivation medium as well as energy consumption and workload. The potential of cold-adapted bacteria to produce lipase and hydrolyse waste oils under non-sterile culture conditions was first tested in the current study.

Screening and characterization of a novel Antibiofilm polypeptide derived from filamentous Fungi.

In the present study, 120 fungal isolates were locally isolated from soil and selected according to their ability to antimicrobial activity. Then, selected isolates were tested for their ability to prevent biofilm formation and only one isolate (A01) showed an antibiofilm effect. The isolate A01 identified as Aspergillus tubingensis by sequencing of the 18S ITS region and a segment of ß-tubulin gene. Then, 5 fractions were prepared from the culture filtrate of A. tubingensis A01 using the ultrafiltration technique to find active polypeptide fraction. The experiments revealed that one of them had an antibiofilm activity. The MALDI-TOF/MS analyses demonstrated that this polypeptide composed of 92 amino acids and had a molecular mass of 10,087 Da. The sequence alignment showed homology with hypothetical protein (OJI81679.1). The gene coding for this polypeptide consisting of 279 nucleotides, herein we called astucin, was cloned and sequenced from A. tubingensis A01 to confirm results. The MIC of the purified polypeptide was 32 m/L and 128 µg/mL and the MBIC was 2 and 8 µg/mL against Staphylococcus aureus and MRSA, respectively. The results demonstrated that the antimicrobial and antibiofilm activity of astucin, together with its lack of cytotoxicity, makes it an alternative for application in medicine. SIGNIFICANCE: Antibiotic resistance is a global problem and the emergence of antibiotic resistant bacteria reduce the effect the current treatment approaches. In this context, antimicrobial peptides stand out as potentional agents to combat bacterial infection especially, biofilm related infections. Importantly, this study have greatly considered our understanding for fungal derived antibiofilm polypeptides. In this study, traditional selection method combined with crystal violet assay is used to investigate antibiofilm polypeptides. We identified antibiofilm polypeptides purified from A. tubingensis A01. This protein shows antimicrobial and antibiofilm activity against S. aureus.

Bacillus pasinlerensis sp. nov., a thermophilic bacterium isolated from a hot spring in Turkey.

A Gram-reaction-positive, endospore-forming bacterium, designated strain P1T, was isolated from water samples collected from Pasinler Hot Spring and characterized using a polyphasic approach to clarify its taxonomic position. Strain P1T was found to have chemotaxonomic and morphological characteristics consistent with its classification in the genus Bacillus. The strain shared the highest 16S rRNA gene sequence identity values with Bacillus thermolactis R-6488T (97.6 %) and Bacillus kokeshiiformis MO-04T (97.2 %) and formed a distinct clade with both type strains in the phylogenetic trees based on 16S rRNA gene sequences. Strain P1T could grow optimally at 55 °C and in the presence of 2 % NaCl. The organism was found to contain meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The predominant menaquinone was determined to be MK-7. The major cellular fatty acids were identified as iso-C15 : 0, iso-C17 : 0 and anteiso-C17 : 0. Based upon the consensus of phenotypic and phylogenetic analyses, strain P1T represents a novel species of the genus Bacillus, for which the name Bacillus pasinlerensis sp. nov. is proposed. The type strain is P1T (=DSM 107529T=CECT 9885T=NCCB 100674T).

Efficient expression of recombinant human telomerase inhibitor 1 (hPinX1) in Pichia pastoris.

PinX1 encoded by a remarkable tumor suppressor gene and located in human chromosome 8p23 is known as telomerase inhibitor. In recent years, this protein has been of interest as clinically tumor suppressor. Pichia pastoris expression system is preferred to produce heterologous proteins and is suitable for industrial and research purposes. In the present study, human PinX1 gene (hPinX1) was cloned in E. coli One Shot TOP10 cells and overexpressed in P. pastoris strain X-33 intracellularly, using a strong AOX (alcohol oxidase) promoter. The recombinant cells were grown in shaking flask. Induction time, methanol concentration and initial pH were optimized for obtaining high levels of hPinX1 protein production. Recombinant protein production was confirmed by Western blot analysis and the relative expression levels of rhPinX1 were quantified. According to Western blot analysis, molecular mass of produced hPinX1 was determined as 47.5 kDa. At the end of optimization studies, the best fermentation conditions were determined as induction time 48 h, methanol concentration 3% and initial culture pH 5.0. This process would be an applicable way for obtaining recombinant hPinX1 using P. pastoris expression system. This is the first report on recombinant production of hPinX1 in P. pastoris.

A new strategy for improved glutathione production from Saccharomyces cerevisiae: use of cysteine- and glycine-rich chicken feather protein hydrolysate as a new cheap substrate.

BACKGROUND: Glutathione (GSH) is composed of the amino acids glutamic acid, cysteine and glycine. This study investigated the usability of chicken feather protein hydrolysate (chicken feather peptone, CFP) as a substrate for GSH production from Saccharomyces cerevisiae. RESULTS: CFP was found to be rich in ash (36.7 g per 100 g), protein (61.1 g per 100 g) and minerals (S, P, K, Ca, Fe, Na and Mg). It also had high contents of cysteine and glycine. CFP augmented biomass and GSH production by 53 and 115% respectively compared with the control medium. The highest biomass (17.4 g l(-1)) and GSH (271 mg L(-1)) concentrations were attained in CFP medium. The second highest biomass (16.8 g l(-1)) and GSH (255 mg L(-1)) concentrations were obtained in fish peptone medium. It was assumed that the high mineral, cysteine and glycine contents of CFP were related to cell growth and GSH synthesis in S. cerevisiae. CONCLUSION: This is the first report on the effect of cysteine- and glycine-rich protein hydrolysates on GSH production from S. cerevisiae. In this regard, CFP was tested for the first time as a GSH production substrate. As an additional contribution, a new hydrolysis process was developed for the preparation of protein hydrolysates.

Effects of progesterone, ß-estradiol, and androsterone on the changes of inorganic element content in barley leaves.

The present study was performed to determine the changes in inorganic element content in barley leaves of mammalian sex hormones (MSH). Barley leaves were sprayed with 10(-4), 10(-6), 10(-9), 10(-12), 10(-15) M concentrations of progesterone, ß-estradiol, and androsterone at 7th day after sowing. The plants were harvested at the end of 18 days after treatment with MSH solutions. The inorganic element concentrations were determined using wavelength dispersive X-ray fluorescence spectroscopy technique. Although the all MSH concentrations significantly (p < 0.05) increased the concentrations of calcium, magnesium, phosphorus, sulfur, copper, manganese, aluminum, zinc, iron, potassium, and chlorine, it decreased those of sodium concentration in barley leaves. The maximum changes in the element concentrations were obtained at 10(-9) M for plant leaves treated with progesterone, 10(-6) M for plant leaves treated with ß-estradiol and androsterone. The present study elucidated that MSH significantly (p < 0.05) affected the inorganic element concentrations in barley leaves.