Corchorus olitorius aqueous extract attenuates quorum sensing-regulated virulence factor production and biofilm formation

Objective:To investigate the effect of Corchorus olitorius aqueous fraction (COAF) on quorum sensing (QS)-regulated virulence factors and biofilm formation in Pseudomonas aeruginosa (PAO1). Methods:The preliminary screening of the anti-QS effect of COAF was performed by evaluating the anti-pathogenic activity against Chromobacterium violaceum CV026 biosensor strain. Next, the inhibitory effects of COAF on QS-regulated pyocyanin production, proteolytic and elastolytic activities, swarming motility, and biofilm formation were evaluated in PAO1.Results:The results showed that the treatment of COAF significantly decreased the biofilm biomass, attenuated virulence factors, and inhibited swarming motility of PAO1 without affecting the growth of the bacteria in a dose-dependent manner. COAF at 2000 μg/mL significantly decreased Las B elastase activity in PAO1 culture, exopolysaccharide production, swarming motility, pyocyanin level, and biomass of PAO1 by 55％ (P<0.05), 60％ (P<0.01), 61％ (P<0.01), 65％(P<0.01) and 73％ (P<0.01), respectively. In addition, the production of violacein was decreased by 62％ (P<0.01) with the treatment of a high dose of COAF. Conclusions:These findings indicate that COAF can be a potential source of anti-QS agents.

Two new imidazole alkaloids from leucetta chagosensis sponge

Chemical investigation of the sponge Leucetta chagosensis, has led to the isolation of two new imidazole alkaloids, methyldorimidazole [1], preclathridine B [2] along with the know compounds naamine E [3] and leucettamine C [4]. The structures of the newly compounds [1 and 2] were elucidated by employing spectroscopic techniques [[1] HNMR, MS and UV]. The structures of the known compounds 3 and 4 were determined by comparison of their [1] HNMR and Mass spectroscopic data with published values

Bromopyrrole alkaloids from marine sponge Agelas oroides

Following a bioassay-guided approach four bromopyrrole alkaloids, oroidin [1], 4,5-dibromopyrrole-2-carboxanijde [2], 4,5-dibromopyrrole-2-carboxylic acid [3] and 4,5-dibromopyrrole-2-[N methoxymethyl] carboxamide [4], were isolated from the bioactive ethyl acetate extract of the tropical marine sponge Agelas oroides. The structures of the isolated compounds were elucidated using their UV, NMR [I D and II D] and mass spectra. Fish feeding, brine shrimp, cytotoxic activity against L5178Y and Hela cell lines, protein kinase inhibition test and the antimicrobial activities for the isolated compounds were investigated. The fish-feeding assay showed that the total alcoholic extract was highly active and the major compound, oroidin, is responsible for this activity [in concentration of 80 mg/10 ml]

Studies on the prevalence of antibodies for Peste des Petits Ruminants [PPR] and Rinderpest [RP] virus in sheep and goats sera

A total of 182 sera samples were collected from two sheep breeds [mixed and Barki sheep] as well as goats raised under arid conditions and examined by serum neutralization test [SNT] for neutralizing antibodies of PPR and RP viruses. The results showed that at 1: 4 serum dilution, 29.41% of mixed breed sheep, 29.82% of Barki sheep and 29.82% of goats sera contained antibodies to PPR virus, while 2.9%, 12.28% of the two sheep breeds, respectively, and 7% of goats sera had antibodies to RP virus. It could be concluded that the prevalence of neutralizing antibodies to PPR virus is equal in sheep and goats. There is no significant difference between the two sheep breeds tested for PPR virus antibodies, but RP virus antibodies is higher in the sera of Barki sheep than that of the mixed breed sheep and the antibodies for PPR virus in the two sheep breeds are more prevalent than in goats