Streptomyces sp. B-PNG23 was selected as a promising cellulolytic strain and tested for its ability to produce cellulases from agroindustrial residues. A pH value of 7 and temperature of 28°C were found to be optimal for maximum enzyme production. The highest endoglucanase activity was obtained in a medium comprised of wheat bran (2 g/l), yeast extract (2 g/l), NaCl (2 g/l), NH4Cl (2.5 g/l), and (0.4 g/l) of MgSO4. The enzyme was active at a broad range of pH (5-8) and temperatures (40-70°C). The optimum pH and temperature were 6 and 50°C, respectively. In the presence of metal ions Mn2+, Cu2+ and NH4 + the activity of the enzyme increased significantly. The enzyme retained 50% of its activity after heating at 50°C for 6 h. This enzyme could be considered as a thermotolerant biocatalyst that could be utilized in biotechnological applications

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Coronavirus disease has become a worldwide threat affecting almost every country in the world. The aim of this study is to identify the COVID-19 cases (positive, recovery and death) in Algeria using the Double Exponential Smoothing Method and an Autoregressive Integrated Moving Average (ARIMA) model for forecasting the COVID-19 cases.The data for this study were obtained from March 21st, 2020 to November 26th, 2020. The daily Algerian COVID-19 confirmed cases were sourced from The Ministry of Health, Population and Hospital Reform of Algeria. Based on the results of PACF, ACF, and estimated parameters of the ARIMA model in the COVID-19 case in Algeria following the ARIMA model (0,1,1). Observed cases during the forecast period were accurately predicted and were placed within the prediction intervals generated by the fitted model. This study shows that ARIMA models with optimally selected covariates are useful tools for monitoring and predicting trends of COVID-19 cases in Algeria.

In the present study, eight single-spore strains of Botrytis cinerea were isolated from tomato greenhouses located in Bejaia regions (Northern Algeria). Isolates were molecularly characterized by nine microsatellite markers. Isolates were assigned to B. cinerea and B. pseudocinerea with four isolates of each species. Morphological characterization was established using two cultures media Potato Dextrose Agar and Malt Extract Agar. All isolates inoculated on PDA medium were exclusively Sclerotial and Mycelial on MEA medium. Aggressiveness of both species was similar on tomato leaves and apple fruits. Moreover, B. cinerea isolates were more aggressive than B. pseudocinerea on lettuce leaves. Tomato and lettuce leaves were significantly more susceptible to the both fungi. A negative correlation was established between aggressiveness and morphological type. Phenotypic variability is considered of major importance to explain the epidemiology of the two cryptic species.

A new actinobacteria isolate was discovered from Algerian soil. It was labeled AZ. It was detected for its antifungal activity against various pathogenic fungi. Cultural characteristics assessed in different media suggested that this isolate belonged to Micrococcus genus. The nucleotide sequence of the 16S rRNA gene (1315 pb) of AZ isolate revealed close similarity 100% with Micrococcus lylae DSM 20315T. The physiological analysis of AZ isolate showed significant differences with nearest species of Micrococcus genus. The antifungal activities of AZ isolate were studied through its large antifungal spectrum. Micrococcus lylae sp. nov.AZ isolate showed antifungal activity against at least 22 fungi and the most are pathogens. The results indicate that Micrococcus lylae sp. nov.AZ isolate has an interesting potential for the production of various bioactive substances.

Background: The prevalence of extended-spectrum b-lactamase (ESBL)-producing Enterobacterales (ESBL-E) and carbapenemase-producing Enterobacterales (CPE) is now disseminated worldwide. This study aims to describe the prevalence of ESBL and CPE fecal carriage in colorectal cancer patients. Methods: All patients admitted to the oncology service of Amizour hospital (Algeria) for colorectal cancer chemotherapy from March to May 2019 were screened for ESBL-E or CPE fecal carriage. After culturing on chromogenic media, the presumptive colonies were identified by mass spectroscopy. Antibiotic susceptibility testing was performed according to the European Committee on Antimicrobial Susceptibility Testing. The b-lactamases encoding genes and plasmid-mediated quinolone-resistant genes were screened by PCR and sequencing. Results: ESBL-E strains were recovered from rectal swabs in 6 patients (14.3%) and only 1 patient (2.4%) was found a carrier for OXA-48-producing Klebsiella pneumoniae. The most frequently encountered species among ESBL-E was Escherichia coli (n = 5), followed by K. pneumoniae (n = 1). PCR and sequencing showed that four isolates harbored the bla CTX-M-15 gene and two strains harbored the bla CTX-M-14 gene. Also, one strain of K. pneumoniae was found to harbor both qepA and qnrS genes. Conclusion: This study highlighted the fecal carriage of ESBL-E and OXA-48-producing Enterobacterales strains in colorectal cancer patients.

Background: COVID-19 has become a worldwide threat affecting every country. Aims: This study aimed to identify COVID-19 cases in Algeria using times series models for forecasting COVID-19. Methods: Confirmed COVID-19 daily cases data were obtained from 21 March 2020 to 26 November 2020 from the Algerian Ministry of Health. Forecasting was done using the Autoregressive Integrated Moving Average (ARIMA) models (0,1,1) with Minitab 17 software. Results: Observed cases during the forecast period were accurately predicted and placed within prediction intervals generated by ARIMA. Forecasted values of COVID-19 positives, recoveries and deaths showed an accurate trend, which corresponded to actual cases reported during 252, 253 and 254 days. Results were strengthened by variations of less than 5% between forecast and observed cases in 100% of forecasted data. Conclusion: ARIMA models with optimally selected covariates are useful tools for predicting COVID-19 cases in Algeria.

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