Purification and kinetic behavior of glucose isomerase from Streptomyces lividans RSU26.

Glucose isomerase (GI), an enzyme with deserved high potential in the world market. GI plays a major role in high Fructose Corn Syrup Production (HFCS). HFCS is used as a sweetener in food and pharmaceutical industries. Streptomyces are well-known producers of various industrially valuable enzymes, including Glucose isomerase. Currently, recombinant strains have been available for the production of various enzymes, but it has limitation in the large scale production. Therefore, identifying effective streptomyces strains have emerged. The current study, the novel S. lividans RSU26 was isolated from a marine source and optimized its potential to produce glucose isomerase at different physical and chemical conditions. The optimum pH and temperature for GI and biomass production were 7.5 and 35 °C, respectively at 96 h. Characterization study revealed that the approximate molar mass of GI was 43 kDa for monomeric and 170 kDa for tetrameric forms. Kinetic behavior exhibits Km, and Vmax values for the conversion of fructose to glucose conversion were 48.8 mM and 2.54 U mg-1 at 50 °C and glucose to fructose were 29.4 mM and 2.38 U mg-1 at 65 °C protein, respectively. Therefore, the present study suggested that the wild-type S. lividans RSU26 has strong potential to produce glucose isomerase for various industrial applications.

Green synthesis and characterization of gold nanoparticles using endophytic fungi Fusarium solani and its in-vitro anticancer and biomedical applications.

The present study aimed to explore the anticancer potentials of the gold nanoparticles (NPs) obtained by green synthesis method using an endophytic strain Fusarium solani ATLOY - 8 has been isolated from the plant Chonemorpha fragrans. The formation of the NPs was analyzed by UV, FTIR, SEM and XRD. The synthesized NPs showed pink-ruby red colors and high peak plasmon band was observed between 510 and 560 nm. It is observed that intensity of absorption steadily increases the wavelength and band stabilizes at 551 nm. The XRD pattern revealed the angles at 19, 38.32, 46.16, 57.50, and 76.81° respectively. Interestingly, the FTIR band absorption noted at 1413 cm-1, 1041 cm-1 and 690 cm-1 ascribed the presence of amine II bands of protein, C-N and C-H stretching vibrations of the nanoparticles. SEM analysis indicated that the average diameter of the synthesized nanoparticles was between 40 and 45 nm. These NPs showed cytotoxicity on cervical cancer cells (He La) and against human breast cancer cells (MCF-7) and the NPs exhibited dose dependent cytotoxic effect. IC50 value was 0.8 ± 0.5 µg/mL on MCF-7 cell line and was found to be 1.3 ± 0.5 µg/mL on MCF-7 cell lines. The synthesized NPs induced apoptosis on these cancer cell lines. The accumulation of apoptotic cells decreased in sub G0 and G1 phase of cell cycle in the MCF-7 cancer cells were found to be 55.13%, 52.11% and 51.10% after 12 h exposure to different concentrations. The results altogether provide an apparent and versatile biomedical application for safer chemotherapeutic agent with little systemic toxicity.

Sonochemical synthesis and fabrication of honeycomb like zirconium dioxide with chitosan modified electrode for sensitive electrochemical determination of anti-tuberculosis (TB) drug.

Herein, novel honeycomb like zirconium dioxide with chitosan (ZrO2@chitosan) nanocomposite have been designed through a facile ultrasound-assisted method and followed by a simple sonication process (bath-type ultrasound washer; Honda Electronics-W-118T; 100 W/cm2 and 300 kHz frequency). After then, as-synthesized ZrO2@chitosan was characterized by FESEM, XRD and EIS. The ZrO2@chitosan nanocomposite modified glassy carbon electrode shows excellent electrochemical sensing performance towards anti-tuberculosis drug (rifampicin). Furthermore, the ZrO2@chitosan modified and fabricated electrochemical sensor showed a wide linear range between 0.015 µM and 547.4 µM and nanomolar detection limit (7.5 nM). Moreover, the ZrO2@chitosan modified electrode showed selectivity towards the detection of anti-tuberculosis drug (rifampicin). The ZrO2@chitosan nanocomposite film modified non-enzymatic sensor has high stable and good reproducible towards the detection of rifampicin. In addition, the as-synthesized ZrO2@chitosan nanocomposite modified electrode has been applied to the determination of rifampicin in biological samples such as human serum and urine samples.

Characterization of pyrene and chrysene degradation by halophilic Hortaea sp. B15.

Polycyclic aromatics hydrocarbons (PAHs) are ubiquitous and toxic pollutants that are dangerous to humans and living organism in aquatic environment. Normally, PAHs has lower molecular weight such as phenanthrene and naphthalene that are easy and efficient to degrade, but high-molecular-weight PAHs such as chrysene and pyrene are difficult to be biodegraded by common microorganism. This study investigated the isolation and characterization of a potential halophilic bacterium capable of utilizing two high-molecular-weight PAHs. At the end of the experiment (25-30 days of incubation), bacterial counts have reached a maximum level (over 40 × 1016 CFU/mL). The highest biodegradation rate of 77% of chrysene in 20 days and 92% of pyrene in 25 days was obtained at pH 7, temperature 25 °C, agitation of 150 rpm and Tween 80 surfactant showing to be the most impressive parameters for HMWPAHs biodegradation in this research. The metabolism of initial compounds revealed that Hortaea sp. B15 utilized pyrene to form phthalic acid while chrysene was metabolized to form 1-hydroxy-2-naphthoic acid. The result showed that Hortaea sp. B15 can be promoted for the study of in situ biodegradation of high molecular weight PAH.

Antimicrobial, antioxidant properties and chemical composition of seaweeds collected from Saudi Arabia (Red Sea and Arabian Gulf).

The present study demonstrates the antibacterial activity of selected brown and green marine algae collected from Saudi Arabia Red Sea and Arabian Gulf. The methanolic and acetone extracts were tested against gram positive, gram negative bacteria and Candida albicans in an attempt to be used as an alternative to commonly used antibiotics. Both brown seaweed species Sargassum latifolium B and Sargassum platycarpum A methanolic extracts were found to be active against gram positive than gram negative; however, S. latifolium acetone extract gave the highest inhibitory activity against Salmonella sp. On the other hand, Cladophorasocialis organic extract demonstrated higher antibacterial activity than the fresh extract but both C. socialis extracts revealed decreased activity compared to Sargassum extracts. Cladophora methanolic extract showed an obvious effect on methicillin resistant Staphylococcus aureus (MRSA). The present work shows a comparable therapeutic potency of the tested seaweed members Sargassum and Cladophora extracts in treating human microbial pathogens to synthetic chemical antibiotics. A remarkable higher antioxidant DPPH free radical scavenging effect was recorded with Sargassum sp. compared to Cladophora sp. FTIR Infrared Spectrometer analysis together with the high performance liquid chromatography provided a detailed description of the possible functional constituents and the major chemical components present in marine macroalgae particularly in brown seaweeds to be mainly of phenolic nature to which the potent antimicrobial activity is being attributed.

Phage typing, PCR amplification for mecA gene, and antibiotic resistance patterns as epidemiologic markers in nosocomial outbreaks of methicillin resistant Staphylococcus aureus.

Staphylococcus aureus is one of the major causes of community and hospital-acquired infections. Bacteriophage considered as a major risk factor acquires S. aureus new virulence genetic elements. A total number of 119 S. aureus isolated from different specimens obtained from (RKH) were distinguished by susceptibility to 19 antimicrobial agents, phage typing, and PCR amplification for mecA gene. All of MRSA isolates harbored mecA gene, except three unique isolates. The predominant phage group is belonging to the (mixed group). Phage group (II) considered as an epidemiological marker correlated to ß-lactamase hyper producer isolates. MRSA isolates indicated high prevalence of phage group (II) with highly increase for phage types (Ø3A), which were correlated to the skin. Phage types (Ø80/Ø81) played an important roll in Community Acquired Methicillin Resistant S. aureus (CAMRSA). Three outpatients MRSA isolates had low multiresistance against Bacitracin (Ba) and Fusidic acid (FD), considered as CAMRSA isolates. It was detected that group I typed all FD-resistant MSSA isolates. Phage groups (M) and (II) were found almost to be integrated for Gentamycin (GN) resistance especially phage type (Ø95) which relatively increased up to 20% in MRSA. Tetracycline (TE) resistant isolates typed by groups (II) and (III) in MSSA. Only one isolate resistant to Sulphamethoxazole/Trimethoprim (SXT) was typed by (III/V) alone in MSSA. MRSA isolates resistant to Chloramphenicol (C) and Ba were typed by all groups except (V). It could be concluded that (PERSA) S. aureus isolates from the wound that originated and colonized, and started to build up multi-resistance against the topical treatment antibiotics. In this study, some unique sporadic isolates for both MRSA and MSSA could be used as biological, molecular and epidemiological markers such as prospective tools.