Background Phenolic compounds from Citrus are known to be a topic of many studies due to their biological properties including antioxidant activity. Methods Methanolic and aqueous extracts were isolated from Citrus leaves of different species (C. clementina, C. limon, C. hamlin, C. navel, C. aurantifolia, C. aurantium and C. grandis) harvested in Algeria. Results The results showed that aqueous extracts of all species are rich in total phenolic compounds and flavonoids (from 68.23 to 125.28 mg GAE/g DM) and (from 11.99 to 46.25 mg QE/g DM) respectively. The methanolic and aqueous extracts were examined for in vitro antioxidant properties using various antioxidant assays. For aqueous extracts, C. limon showed an important DPPH radical scavenging activity (IC50 35.35 µg/mL), and C. clementina exerted the highest ABTS radical scavenging activity (1,174.43 µM ET/g DM) and a significant ferric reducing potential (30.60 mg BHAE/g DM). For methanolic extracts, C. clementina showed the highest antioxidant activity for all the realized assays (IC50 41.85 µg/mL, 378.63 µM ET/g DM and 13.85 mg BHAE/g DM) for DPPH, ABTS radicals scavenging activities and ferric reducing potential respectively. Antiperoxidase and antipolyphenol oxidase activities of these samples were also evaluated. Conclusions In this investigation, the assessment of antiperoxidase activity proved that the leaves extracts of different species were able to inhibit peroxidase activity. However, this inhibition varied with the species and the source of these enzymes. On the other hand, the aqueous extracts of different species showed moderate inhibition of polyphenol oxidase, while no effect on these enzymes was obtained with methanolic extracts.

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To estimate the genetic diversity and population structure for a better understanding of the spread of Botrytis cinerea, we genotyped with nine microsatellite markers 174 isolates collected from four greenhouses during three growing seasons in the region of Bejaia. Four of these isolates were detected as Botrytis pseudocinerea according to the allele size at locus Bc6. For all other isolates further studied, all loci were polymorphic, with the mean number of alleles per locus ranging from 2.77 to 5.22. Considerable genetic variability was detected in all subpopulations (D* > 0.87; Hnb > 0.40). Based on the standardized index of association analysis, significant but low levels of clonality occurred, not excluding the possibility of recombination (rD = 0.07, P < 0.001). A total of 109 haplotypes were characterized among the isolates, few of which were shared between subpopulations. This, together with moderate genetic differentiation among subpopulations according to the geographical origin (0.080 < FST < 0.167), suggested a low level of inoculum exchange among greenhouses and little carry‐over of inoculum from one sampling season to the next. The importance of genetic structure of B. cinerea populations is discussed and should be taken into consideration for the management of grey mould.

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.

a b s t r a c tThe objective of this work is to promote carbide lime waste (CLW), rejected in nature to reduce the pathogens in urban wastewater sludge. We have engaged in this research project, which is notably based on an integrative approach to CLW in urban sludge stabilization. Due to their intrinsic physical and chemical properties, CLW showed excellent and attractive results for urban wastewater sludge stabilization of Bordj Bou Arreridj city. The obtained results show that the stabilization of sludge is most efficient with high level of CLW percentage. The best elimination of pathogenic microorganisms and dryness is obtained for a 50% CLW dose for various microorganisms such as fecal D Streptococcus, fecal coliform, total mesophilic flora and sulfate-reducing clostridium bacteria. Therefore, the valuing of CLW efficiency in the laboratory showed that their valorization could be extended to the sludge stabilization field.

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.