Molecular identification, characterization, and antagonistic activity profiling of Bacillus cereus LOCK 1002 along with the in-silico analysis of its presumptive bacteriocins.

Objectives: This research aimed to isolate, identify, and characterize a new strain of Bacillus cereus through different molecular biology approaches so that it could be further studied for therapeutic purposes against selective enteric pathogens. Materials and Methods: Pure isolates of B. cereus were prepared from buffalo yogurt samples in REMBA medium. Initially, the morphological, physiological, and biochemical properties were studied accordingly. Following the tests, the molecular identification for the strain identification was conducted through plasmid DNA extraction, PCR, agarose gel electrophoresis, and 16S rRNA sequencing up to 1.37 kb. Afterward, the antibiotic sensitivity [Epsilometer test (E-Test)] and antifungal activity were tested considering different concentrations. Being classified from the aforementioned tests, a comprehensive antimicrobial activity test was conducted using the cell-free-supernatant (CFS) of the test strain against selective enteric pathogens in humans in vitro. Besides, the different clusters of genes were identified and characterized for understanding the presumptive bacteriocins present in the CFS of the strain in silico, where molecular string properties were calculated. Finally, the evolutionary relationship among diversified bacteriocins synthesized by different Bacillus strains was studied to predict the CFS-containing bacteriocins of the new strain. Results: Purified isolates of B. cereus were Gram-positive rods and showed significant tolerance (p < 0.0001) to different concentrations of pH, phenol, bile salt, and NaCl. 16S rRNA revealed the strain as LOCK 1002, which was strongly sensitive to all the antibiotics used and resistant to selective antifungal agents. The CFS of B. cereus LOCK 1002 was found to be a very promising antagonist to all the enteric pathogens used in the culture condition. Two gene clusters were predicted to be interconnected and responsible for different presumptive bacteriocins. Conclusion: The newly identified LOCK 1002 can be a very potent strain of B. cereus in use as an antimicrobial agent for having different bacteriocin coding gene clusters.

Phytochemical and in vitro biological investigations of methanolic extracts of Enhydra fluctuans Lour.

OBJECTIVE: To study the phytochemical and biological properties (antioxidant, anthelmintic and thrombolytic) of methanolic extracts of Enhydra fluctuans Lour., a plant belonging to the Asteraceae family. METHODS: The phytochemical evaluation was carried out by qualitative analysis. In vitro antioxidant activity of extract was studied using free radical scavenging assay, ability of reduction, total phenol and total flavonoid contents determination assays. The anthelmintic activity was determined using paralysis and death time of Pheretima posthuma (earthworm) and thrombolytic activity by clot disruption assay. RESULTS: The phytochemical evaluation showed significant presence of flavonoids, triterpenes, carbohydrate, reducing sugars, saponins, phenols, diterpenes, protein and tannin. The antioxidant activity was found significant [IC50=(135.20±0.56) µg/mL] as compared to ascorbic acid [(130.00±0.76) µg/mL]. The reducing power was increased with concentration. Total phenol and total flavonoid contents were (153.08±0.38) mg/mL and (172.04±0.56) mg/mL respectively. The paralysis and death time of earthworms for different concentrations of extract were determined and compared with albendazole. The results showed that 10 mg/mL of the crude extract had similar effect with albendazole. Additionally, the crude extract showed a concentration depended relationship with its anthelmintic property. The clot lysis activity of crude extract was compared to the standard streptokinase's clot lysis (40.13%) activity and found significant (31%). CONCLUSIONS: The study proves that the crude methanolic extract of Enhydra fluctuans Lour. has significant antioxidant, anthelmintic and thrombolytic activity containing wide range of phytochemicals.

Determination of the presence and pharmacokinetic profile of ciprofloxacin by TLC and HPLC method respectively in broiler chicken after single oral administration.

The objective of this study was to determine the presence of ciprofloxacin and pharmacokinetics of ciprofloxacin in blood plasma of broiler chicken after single oral administration at feeding state. Ciprofloxacin was administered orally at 10 mg kg(-1) to each of the 10 broiler chickens at feeding state. Presence of ciprofloxacin was determined by TLC method and pharmacokinetics by HPLC method. Peak plasma concentration (Cmax) of ciprofloxacin, 0.26±0.03 mg l(-1) was achieved at 4.40±0.1 h (Tmax). Biological half-life of ciprofloxacin was 5.25±0.02 h. Area under the curve (AUC) was 13.397±0.13 mg ml(-1) h, elimination rate constant was 0.13±0.02 h(-1), volume of distribution was 0.194±0.04 l kg(-1) and bioavailability was 49±0.48%. On the basis of the results of the present study, we conclude that, feeding state may have a vital effect on the pharmacokinetic profile of ciprofloxacin in broiler blood plasma.

Phytochemical and in vitro biological investigations of methanolic extracts of Enhydra fluctuans Lour

Objective: To study the phytochemical and biological properties (antioxidant, anthelmintic and thrombolytic) of methanolic extracts of Enhydra fluctuans Lour., a plant belonging to the Asteraceae family. Methods:The phytochemical evaluation was carried out by qualitative analysis. In vitro antioxidant activity of extract was studied using free radical scavenging assay, ability of reduction, total phenol and total flavonoid contents determination assays. The anthelmintic activity was determined using paralysis and death time of Pheretima posthuma (earthworm) and thrombolytic activity by clot disruption assay. Results:The phytochemical evaluation showed significant presence of flavonoids, triterpenes,carbohydrate, reducing sugars, saponins, phenols, diterpenes, protein and tannin. The antioxidant activity was found significant [IC50=(135.20±0.56) μg/mL] as compared to ascorbic acid [(130.00±0.76) μg/mL]. The reducing power was increased with concentration. Total phenol and total flavonoid contents were (153.08±0.38) mg/mL and (172.04±0.56) mg/mL respectively. The paralysis and death time of earthworms for different concentrations of extract were determined and compared with albendazole. The results showed that 10 mg/mL of the crude extract had similar effect with albendazole. Additionally, the crude extract showed a concentration depended relationship with its anthelmintic property. The clot lysis activity of crude extract was compared to the standard streptokinase’s clot lysis (40.13%) activity and found significant (31%). Conclusions: The study proves that the crude methanolic extract of Enhydra fluctuans Lour. has significant antioxidant, anthelmintic and thrombolytic activity containing wide range of phytochemicals.

Susceptibility of microorganism to selected medicinal plants in Bangladesh

Objective: To analyze in-vitro antimicrobial activities of some ethno-pharmacologically significant medicinal plants (methanol extract) against the pathogenic microorganisms (Escherichiacoli, Salmonella spp., Bacillus cereus, Staphylococcus aureus, Aspergillus niger and Candida albicans).Methods:The disc diffusion method was applied for antibacterial test and the poisoned food technique was applied for antifungal test.Results:The methanol extract of Terminalia chebula (bark), Phyllanthus acidus (fruits), Sarcochlamys pulcherrima (leaves) and Abelmoschus esculentus (fruits) had significant in vitro antibacterial activity angainst the entire test samples in comparison to standard drug ciprofloxacin. Most of the plant extracts showed low activity against Gram negative bacteria while potential activity against Gram positive bacteria. The antifungal activities of methanol extracts of these plants and standard drug griseofulvin were determined against two pathogenic fungi, andPolygonum lapathifolium (leaves) and Cinnamomum tamala (leaves) showed maximum activity, while Erioglossum rubiginosum (leaves) showed no antifungal activity.Conclusions:Further chemical and pharmacological investigations are required to identify and isolate chemical constituents responsible for these potential bioactivities and thus to determine their full spectrum of efficacy.