Journal of Applied Biotechnology Reports
Volume:7 Issue: 4, Autumn 2020

Spot blotch, caused by Cochliobolus sativus, is most effectively managed using fungicide applications, including triadimefon (TDM) a triazole compound. C. sativus posses a great concern as it might develop resistance against fungicides like TDM due to its high genetic variability, short life cycle, and abundant inoculum production. Therefore, to better understand the mechanisms of TDM resistance initiated by C. sativus, changes in cytochrome b (cytb) gene in virulent and avirulent pathotypes were evaluated at early time points of TDM treatments.

C. sativus sensitivity to TDM was determined by measuring the radial growth of each pathotype on PDA plates. Additionally, RNA was isolated from mycelia of each pathotype at 24, 48, 72 and 96 hours post fungicide treatments and used for cDNA synthesis. Cytb was verified using quantitative reverse transcriptase PCR (qRT-PCR).

Data showed that the maximum mycelial growth inhibition by 50% (EC50) for both pathotypes was recorded 48h at 0.25 µg/ml TDM treatment. The qRT-PCR revealed that cytb expression increased in both virulent and avirulent pathotypes at 24h post TDM treatments in comparison with non-treated controls. The most outstanding differences in cytb expression were7.69 and 2.88-fold in the virulent and avirulent pathotypes, respectively, 48h of 0.25 µg/ml TDM treatment.

According to findings, it is possible to propose that cytb gene might play a role in signaling events during C. sativus exposure to commercial triazole fungicide.

Plasmid-mediated quinolone resistance (PMQR) is a growing clinical concern throughout the world. The purpose of this study was to detect qnr-encoding genes and to evaluate the clonal relatedness of qnr-positive Klebsiella pneumoniae isolates. A total of 88 K. pneumoniae isolates assessed to quinolone which were obtained from Tehran hospital in Tehran, Iran. Bacterial identification was administrated using standard laboratory methods. Quinolone resistance was determined using the Kirby-Bauer disk diffusion method according to the Clinical Laboratory Standards Institute (CLSI) guidelines. The PCR was employed to detect qnrA, qnrB and qnrS genes. The results of disk diffusion showed that 39.3%, 32.1%, 27.4%, 27.1%, 22.6% of strains were fully resistant to nalidixic, norfloxacin, ofloxacin, ciprofloxacin and levofloxacin, respectively. The qnrB (43% isolates) was the most commonly detected gene, followed by qnrS (34% isolates) and qnrA (23 % isolates) either alone or in combination with other genes. This study describes the high prevalence of the qnrB, qnrS, and qnrA genes among K. pneumoniae isolates in Iran. The detection of qnr genes accentuate the need for organizing tactful policies associated with infection control measures in hospital settings in Iran.

Bioremediation as an eco-friendly technique has a high potential to clean-up the toxicity of heavy metals from contaminated soil and water. In this study, the bioremediation potential of E8 and WW28 strains which had high similarity to Sphingomonas melonis and Enterobacter hormaechei, respectively have been evaluated under contaminated mediums with lead, cadmium, copper, and nickel. The growth rate and metal removal percentage of isolated strains were investigated at different ranges of pH 4-8, and temperature (25, 30, 35, and 40 ˚C). Also, the bioremediation potential of isolated strains was studied under a mixture of metals (50 mg/L of each metal). The highest cell mass of strain E8 was observed after 48h at 30 ˚C and pH 5 while strains WW28 showed a high growth rate after 72h at 25 ˚C and pH 5. Strains E8 and WW28 preferred to more uptake nickel and copper than lead and cadmium. In addition, cadmium appears to show the highest toxicity towards the isolated bacteria. Strain E8 as multi metals-resistance strain could remove 78, 62, and 56% of nickel, copper, and cadmium, respectively from polluted mediums at pH 6 after 48h. Overall results revealed that isolated strains as bio-tools have a high potential to be used in the bioremediation process of nickel and multi-metals contaminated sites.

Colon cancer is a real public health problem. Pomegranate peel and probiotics are thought to be important therapeutic nutritional strategies for colon cancer prevention. The aim of this study was to evaluate the modulation effect of pomegranate peel alone or in combination with probiotics against the oxidative disorders and intestinal dysbiosis associated with chemically-induced precancerous lesions in rat colon. Materials and  Thirty-six male Wistar rats were divided into six groups: Groups1and 2 were negative DMH-untreated control rats receiving Standard Diet (SD) for G1 and high-fat diet (HFD) for G2; while Groups 3 and 4 were positive DMH-treated control receiving SD for G3 and HFD for G4; Groups 5 and 6 were DMH-treated and fed with 2.5% pomegranate peel-supplemented HFD diet in the presence of probiotics (4×109 CFU/kg diet) for G6. After 16 weeks of experimentation, biochemical analysis, oxidative parameters, histopathological examination of the colon, and microbial analysis were performed. Findings showed that pomegranate peels and probiotics induced a significant increase in ferric reducing the ability of plasma levels by 67% and reduction in the malonaldehyde content by 66%. In addition, this treatment helped to improve the histological architecture of the colon in the rats of groups G5 and G6, in comparison with the HFD positive DMH-treated control group (G4). Furthermore, this treatment was also the most effective in decreasing the pathogenic bacteria amount involved in the intestinal dysbiosis (7 to 43%) and increasing in beneficial bacteria (60%). These results suggest that pomegranate peel and probiotics act as a chemopreventive agent against preneoplastic lesions.

Inflammatory Bowel Disease (IBD) is a term used to denote concurrently the two chronic inflammatory conditions of Gastrointestinal (GI) tract viz: Chron’s Disease (CD) and Ulcerative Colitis (UC). This study has aimed to focus on Acetyl-11-keto-beta-boswellic acid (AKBA) which is an active phytochemical derivate from the gum resin of the Boswellia serrata in order to investigate its anti-inflammatory potential against dextran sodium sulfate-induced colitis in Swiss albino mice. The 3% of Dextran Sodium Sulfate (DSS) polymer in drinking water was fed to different mice groups with distinct timeline for both acute (7days) and chronic colitis induction (3 cycles of 5 days feeding with 15 days gap method). The anti-inflammatory activity of AKBA (50 mg/kg) was evaluated by performing various anti-oxidant assays on tissue homogenate samples (colon, liver, and kidney) and further histological studies. The oral administration of AKBA (50 mg/kg) had managing effects in IBD mice. Results showed that AKBA lowered the inflammation and soreness compared to the DSS administered mice groups. The histopathology of the intestinal wall was performed and clear morphological changes were observed under light microscopy of both acute and chronic colitis groups of mice. Furthermore, various anti-oxidant assays were performed on tissue sections of chronic colitis mice. Results from histological studies indicated that the chemo-preventive effect of AKBA was attributed to a collection of activities including anti-proliferation, apoptosis induction, and anti-inflammation. In accordance with the findings, the AKBA active derivative showed anti-inflammatory activity against the DSS induced acute and chronic colitis in mice. However, further clinical studies need to be done to bring AKBA as a potential anti-inflammatory drug candidate for treating IBD.

Introdution: 

Some health instructions and proceedings were widely broadcasted and advised by scientific centers and social media concerning COVID-19 prevention, in the early days of the epidemic. Almost all of them had been sourced from narrative statements or non-evidence based sciences.  Herein, we intended to deeply investigate the usefulness and efficiency of such recommendation on COVID-19 prevention.

Ninety-seven RT-PCR confirmed positive COVID-19 as case, 103 suffering from other diseases as control group were enrolled. To collect the data, an expert validated questionnaire encompassed demographic information, past medical history and pre-infection preventive proceedings (consumption of vitamin  D3, C, and Zinc supplement, wearing face masks and gloves, hand washing, keeping at least 1.5 meters distance with other people, and staying at home) was used. The data between two groups were analyzed using SPSS software version 16.

No significant difference was obtained in Zinc consumption between case and control groups (14 (14.4%) vs 16 (15.5%), OR=0.88, CI= 0.66-1.31). Interestingly, D3 and C vitamins consumption were significantly higher in patients suffering from COVID-19 compared to non-COVID-19 patients, [(60 (61.9%) vs 47 (45.6%), OR=1.28, CI=1.12-1.48) for vitamin D3 and (54 (52.4%) vs 47 (48.4%), OR=1.15, CI=1.01=1.31)]. Hand and face hygiene was significantly more observed in non-COVID-19 patients group (77 (79.3%) vs 96 (93.2%), OR=0.82, CI=0.71-0.93). Home quarantine and keeping social distance were also significantly higher in non-COVID-19 patients group.

General protective proceedings have significant protective roles against COVID-19.

Recent researches have shown that many plant Essential Oils (EOs) have a high potential for controlling agricultural pests and can be used as precursors for synthesis of new pesticides. The major limitations for the use of these compounds are rapid evaporation, poor water solubility, and aptitude for oxidation. The aim of this study was to prepare and characterize nanoliposome containing EOs of Mentha pulegium and Ferula gummosa and fumigant toxicity of nanoliposome containing M. pulegium EOagainst T. castaneum. In this study, nanoliposome containing EOs of M. pulegium and F. gummosa were prepared using heating method and its physicochemical properties were evaluated. Also, the impact of fumigant toxicity of M. pulegium EONanoliposome on M. castaneum was investigated. Results showed that mean (±SD) particles of nanoliposomecontaining M. pulegium and F. gummosa EOs were 345±3.2 and 309±1.67 nm and their encapsulation efficiency were 99.38±0.24% and 96.41±0.26, respectively. The kind of EOs had no significant effect on the physicochemical property of nanoparticles. At the end of 24 h, the release percentage of EOs of nanoliposomes of M. Pulegium and F. gummosa were 46% and 33 %, respectively. The estimated LC50 values for nanoliposome and crude Eos of M. Pulegium against T. castaneum were36.53 and 75.23 µI/I air, respectively. The results of the current research showed that release and stability of EOs were significantly affected when change to nanoliposome particles. Also, M. pleugium EO nanoliposome showed enhancing fumigant toxicity against T. castaneum in comparison with the crude EO of this plant.

Proteases are hydrolyzing enzymes and are considered to be one of the most important groups of enzymes for industry and are used in leather, pharmaceutical, and food industry along with detergents, and bioremediation processes. The main objectives of this study were (i) to extract, partially purify, and characterize the protease enzyme from Moringa (Moringa oleifera) leaves; and (ii) to investigate the effect of such an enzyme against some pathogenic bacteria.

This enzyme was extracted in a 0.1 M phosphate buffer pH 7. It was left for 24 hours in a refrigerator and was then filtered using filter paper Whatman no. 41. The aqueous filtrate was used to estimate the proteolytic activity.

Purification by ammonium sulfate gave the best results at 50%-70% concentration which had the highest specific activity, highest purification fold with the percentage yield of 45.3%. Gel filtration by Sephadex G-100 gave the best specific activity and the best purification fold with the yield from fraction of 34%-43%. The protease enzyme has optimum pH 7 and temperature 50 oC. The enzyme was thermally stable at 40-70 oC for 20-30 minutes. Some metal ions were activator on the enzyme-like Mn2+ (highest), Ba2+, Ca2+, and Na+. The efficacy of protease enzyme was improved when integration with antibiotic against certain bacterial including Bacillus cereus (S3), Staphylococcus aureus, Salmonella typhimurium, Escherichia coli O157:H7, and Listeria monocytogenes. Also, E. coli O157:H7, L. monocytogenes, and Yersinia enterocolitica did not show any growth at pH 10.

To conclude, it can be stated that protease enzyme can be considered as a promising agent, cheap, and safe source which is suitable for using in various industries.

Infections caused by multidrug-resistant Klebsiella pneumonia characterize a major warning throughout the world owing to enhanced mortality and treatment limitations. Efflux pumps have an important role as a mechanism of antibiotic resistance in K. pneumoniae. In the current study, the role of AcrAB and OqxAB efflux pumps to antibiotic resistance was investigated in clinical isolates of K. pneumonia. During August 2017-October 2018, 110 clinical strains of K. pneumoniae were obtained from patients referred to the hospitals in Tehran. After microbiological/biochemical identification, and antimicrobial susceptibility test was performed using the disc diffusion method. Then, the minimum inhibitory concentration of ciprofloxacin-resistant K. pneumoniae strains was measured by the broth microdilution method. For investigating the efflux pump mediated drug resistance in K. pneumoniae, the presence, and prevalence of efflux genes (acrA/acrB and oqxA/oqxB) were examined by the Polymerase Chain Reaction (PCR) technique. The results showed that resistance to ciprofloxacin, norfloxacin, gentamicin, kanamycin, cefotaxime, trimethoprim, chloramphenicol, and colistin was 19.09%, 21.81%, 10.0%, 9.09%, 44.54%, 25.45%, 11.81%, and 61.81%, respectively, in K. pneumoniae clinical isolates. The PCR technique demonstrated that the prevalence of acrA/acrB and oqxA/oqxB genes are 58 (52.72%) and 52 (47.27%), respectively. The results of this study reveal that the AcrAB and OqxAB efflux pumps have a major role in the antibiotic resistance of multidrug resistance K. pneumoniae isolates. Therefore, due to the easy transfer of antimicrobial resistance genes, the accurate detection of resistance genes by molecular methods is essential to control the spread of resistant strains.

Plantago lanceolata is one the most important species of the Plantago genus and has valuable medicinal secondary metabolites.

The effect of different factors on germination of P. lanceolata seeds was studied and leaf and root explants of in vitro growth seedling were cultured on Murashige and Skoog (MS) medium supplemented with combination of 6-benzylaminopurine (BAP) or thidiazuron (TDZ) (0, 0.5, 1, 1.5, 2 and 3 mg/L) and auxins: α-naphthaleneacetic acid (NAA) (0, 0.2, 0.5, 1 mg/L), Indole-3-acetic acid (IAA) (0.1, 0.5, 1, 1.5 mg/L) or Indole-3-butyric acid (0.5, 1, 1.5, 2 mg/L) (IBA) at different concentrations.

The results showed that cold pre-treatment, daylight and 1/8 MS salt concentration are more suitable for high germination. The best shoot organogenesis rate (95%) in leaf explants was observed in 1:1 mg/L, and 1.5:1 mg/L TDZ: IBA. The highest percentage of shoot organogenesis (100%) was observed in most of the plant growth regulator (PGR) treatments in root explants. About 58.67 and 60 shoot numbers obtained with 2 mg/L TDZ in leaf and 1:1.5 mg/L BAP: IBA in root explants, respectively.

It can be suggested that the best shoot organogenesis and proliferation medium is MS basal medium containing cytokinin TDZ and auxin IBA in comparison with other hormone compounds on leaf and root explants. The result behind this fact is high callus induction and regeneration potential of explants in all concentrations.