ANTILEISHMANIAL ACTIVITY OF SOME PLANTS GROWING IN ALGERIA: JUGLANS REGIA, LAWSONIA INERMIS AND SALVIA OFFICINALIS.

The current study was undertaken to evaluate in vitro the antileishmanial activity of three plants growing wild in Algeria : Juglans regia, Lawsonia inermis and Salvia officinalis. The hydroalcoholic extracts of these plants were tested on the growth of the promastigotes of Leishmania major. The plant extract effects were compared with three controls : CRL1 composed of 1 ml RPMI inoculated with 106 of promastigotes, CRL2 composed of 1 ml RPMI inoculated with 106 of promastigotes and 100 μl of hydroalcoholic solvent, CRL3 composed of 1 ml RPMI inoculated with 106 of promastigotes and 100 μl of Glucantim as a reference drug in the management of leishmaniasis. The results showed that both J. regia and L. inermis extracts reduced the promastigotes number significantly (

Use of bacteria and yeast strains for dairy wastewater treatment

peer reviewedThe present investigation was carried out to study the biodegradation of dairy effluent collected from a regional dairy industry, in Tunisia, by using selected aerobic microbial and yeast isolates. The predominant microorganisms : Candida albicans, Candida krusei, Lactobacillus plantarum and Lactobacillus casei isolated from activated sludge pond of the dairy plant were used. Biodegradation tests were performed in batch into Erlenmeyer flasks containing collected dairy wastewater samples. Two sets of experiments were carried out in duplicate. For the first set of experiments, each bacteria and yeast strain was used for the preparation of four inoculums composed of single culture. These inoculums are added separately in the test samples with a concentration of 1% (v/v). For the second set of experiments, three inoculums rate (1, 5 and 10% (v/v)) were tested. A bacteria and yeast mixed culture were added separately in the test samples. A variable amount of COD, proteins and total sugars reduction was observed with individual and mixture isolates after 25 days treatment period. The chemical oxygen demand (COD) has received reduction varying between 51.6 and 71.6% with individual isolates at 1% (v/v) inoculum rate, while bacterial mixed culture and yeast mixed culture showed reduction up to 75.8 and 70.7% respectively, at 1% (v/v) inoculum rate. Isolates with inoculum rate of 5% (v/v) proved to be most efficient in the treatment of effluent. The highest reduction of total sugar content was obtained by yeast consortium while the highest reduction of protein content was obtained by bacteria consortium

Phosphorylation of Bacillus subtilis gene regulator AbrB modulates its DNA-binding properties

AbrB is a global gene regulator involved in transition phase phenomena in Bacillus subtilis. It participates in a complex regulatory network governing the expression of stationary-phase functions. AbrB was previously found to be phosphorylated on serine 86 located close to its C-terminal oligomerization domain. Here we report that AbrB can be phosphorylated by three B. subtilis serine/threonine kinases expressed during the transition and stationary phase: PrkC, PrkD and YabT. Our in vitro findings suggest that AbrB phosphorylation impedes its DNA binding and abolishes binding cooperativity. In vivo we established that a phospho-mimetic mutation abrB S86D leads to a significant loss of AbrB control over several key target functions: exoprotease production, competence development and sporulation. A wider transcriptome analysis of abrBS86D and S86A mutant strains revealed deregulation of a large number of target genes. We therefore propose that AbrB phosphorylation serves as an additional input for fine-tuning the activity of this ambiactive gene regulator

Survey of Infectious Etiologies of Bovine Abortion during Mid- to Late Gestation in Dairy Herds.

Bovine abortion of unknown infectious etiology still remains a major economic problem. Thus, we investigated whether Brucella spp., Listeria monocytogenes, Salmonella spp., Campylobacter spp. and Coxiella burnetii are associated with abortion and/or stillbirth in Tunisian dairy cattle. Using a pan-Chlamydiales PCR, we also investigated the role of Chlamydiaceae, Waddlia chondrophila, Parachlamydia acanthamoebae and other members of the Chlamydiales order in this setting. Veterinary samples taken from mid to late-term abortions from twenty dairy herds were tested. From a total of 150 abortion cases collected, infectious agents were detected by PCR in 73 (48.66%) cases, 13 (8.66%) of which represented co-infections with two infectious agents. Detected pathogens include Brucella spp (31.3%), Chlamydiaceae (4.66%), Waddlia chondrophila (8%), Parachlamydia acanthamoebae (5.33%), Listeria monocytogenes (4.66%) and Salmonella spp. (3.33%). In contrast, Campylobacter spp. and Coxiella burnetii DNA were not detected among the investigated veterinary samples. This demonstrates that different bacterial agents may cause bovine abortion in Tunisia. This is the first report suggesting the role of Parachlamydia acanthamoebae in bovine abortion in Africa. Further studies with a larger number of samples are necessary to confirm whether this emerging pathogen is directly linked to abortion in cattle