Bacillus cereus is a group of bacteria frequently found in soil, widely distributed in the environment. They are a group of ubiquitously facultative anaerobic spore-forming Gram-positive rods and are of health and economic benefits. The present study was conducted to identify, characterize about 36 B. cereus and examined for their potential plant growth promoting (PGP), which was tested in vitro. Parameters assessed were indole acetic acid (IAA) production, phosphate solubilization, starch hydrolysis, proteolytic activity and biofilm formation. Multiple B. cereus were isolated from several soil plots from South-Western region of Algeria and characterized by using phenotypic methods including fatty acid methyl ester. Ten bacterial isolates were examined in this study. Fatty acid profiles showed that bacterial isolates were classified into B. cereus group, three isolates were B. cereus Subgroup "A" and seven isolates were B. cereus Subgroup "B". Temperature effect on the maximal specific growth rate was studied in B. cereus between 10 and 50°C, no growth was observed in 10°C, all B. cereus isolates grown from 15 to 45°C and no grown observed in 20 to 50°C. This study demonstrates adaptation of isolates of the B. cereus group to different habitats. The ability to solubilize precipitated phosphate was positively exhibited by three isolates, five isolates showed ability to produce IAA. All the isolated bacterial isolates had amylolytic and proteolytic activity. All isolates did not form a biofilm in the microtiter plate assays, while all B. cereus in our study formed biofilm in tubes at air-liquid interfaces.

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Traditional medicine has a key role in health care worldwide; the research for antimicrobial agents from plants has been a growing interest in the last few decades. Several studies indicate the presence of potent antibacterial agents in the seeds of Linum usitatissimum L. In the present study, antibacte-rial properties of mucilage extract from Linum usitatissimum L. seeds were screened against against eight Gram positive and Gram negative pathogenic bacteria using agar well diffusion method and disk diffusion method. The extract showed good results against examined bacteria and the results ob-tained by agar well diffusion method were better than those obtained from disk diffusion method. The mucilage showed strong antibacterial properties against all strains tested except Listeria monocytogenes with; the diameter of the inhibition zones (IZD) varying from 8 to 12 mm.The results of this study suggested that the mucilage from L. usitatissimum L can be a source of natural antibacterial agent.

Food poisoning is a serious public health problem in the world that needs to be addressed as early as possible. However, mitigation efforts can be possi-ble only when data and information resulting from the implementation of monitoring or continuous surveillance are available. Here we report a study that was conducted taking into account all the data of poisoning report sheets, filled in by the doctor in charge of the case or, failing that, by the nurse, coming from health facilities (in sixteen regions in Tlemcen) were in-cluded in the analysis. For data processing, we have used some descriptive tools such as the frequencies and the lethality rates. The description of the sample concerned the characteristics of the poisoned population (year, gen-der, age, origin, hospitalisation, etc.) and the characteristics related to the suspected food. The survey showed a concentration of family focus, espe-cially in urban areas. Meats, Chickens and cream filled bakery food were the three most important incriminated foods and most of the infections in the outbreaks were related to fecal coliform, Clostridium and Staphylococcus. Some of the factors identified to contribute to food poisoning were lack of self-hygiene by food handlers and poor water and environmental supplies, poor preservation of food, the consumption of inadequately cooked or thawed meat or chicken, cross-contamination of food from infected food handlers, as well as the lack of awareness and information transmission and the lack of health infrastructures and means of communications. The present study highlights the needs for creating adequate infrastructure related to hygiene, regular epidemiological monitoring and increasing the awareness level of the residents.

In previous work, 70 Bacillus sp. isolates originating from 4 soil plots from southwestern Algeria were studied for their poten al plant growth promoting (PGP). In this study, pH, organic ma er, texture, Calcium carbonate, and Electrical conduc vity of the soil samples were determined, 08 selected isolates were idenfied based on rRNA 16S and FAME analysis using GC. Antimicrobial activity against bacteria and fungi were also investigated. All the four soils were moderately Calcium carbonate, pH of soil was alkaline. Our results showed that the electrical conductivity was high for all soils and the four soil isolates in semi-arid and arid regions were poor in organic matter. In addition, Fatty acid analysis showed the presence of 17 di erent fa y acids. Three fa y acids, 15:0 iso, 16:0, and 17:0, 17:0 were present in all isolates. Thus, the isolates were classified into two clusters which were con rmed the results of 16SrRNA sequence analysis. Preliminary screening revealed that the Bacillus thuringiensis isolates showed strong an bacterial and an fungal proper es against S. aureus (between 7mm to 11mm) and A. niger (between 7mm to 8mm). The aim of the present study is the screening of eight Bacillus cereus strains isolated from four rhizosphere soil sample of South-Western region of Algeria province for their an microbial activity.