Antibacterial, antibiofilm, and anti-adhesion activities of Piper betle leaf extract against Avian pathogenic Escherichia coli.

Piper betle leaves have traditionally been used to treat many diseases, including bacterial infections. The present study aimed to investigate the antibacterial, antibiofilm, and anti-adhesion activities of P. betle extract against avian pathogenic Escherichia coli (APEC). The ethanol extract of P. betle leaves demonstrated strong antibacterial activity against clinical isolates of APEC with MIC and MBC values ranging from 0.5 to 1.0 mg/mL as compared with 1% DMSO, a negative control. Disruption and breakdown of the bacterial cells were detected when the cells were challenged with the extract at 2 × MIC. Bacterial cells treated with the extract demonstrated longer cells without a septum, compared to the control. The extract at 1/8, 1/4, and 1/2 × MIC significantly inhibited the formation of the bacterial biofilm of all the tested isolates except the isolate CH10 (P < 0.05) without inhibiting growth. At 1/2 × MIC, 55% of the biofilm inhibition was detected in APEC CH09, a strong biofilm producer. At 32 × MIC, 88% of the inhibition of viable cells embedded in the mature biofilm was detected in APEC CH09. Reduction in the bacterial adhesion to surfaces was shown when APEC were treated with sub-MICs of the extract as observed by SEM. Hydroxychavicol was found to be the major compound presented in the leaf extract as detected by GC-MS analysis. The information suggested potential medicinal benefits of P. betle extract to inhibit the growth, biofilm, and adhesion of avian pathogenic E. coli.

Evaluation of Antimalarial Potential of Aqueous Crude Gymnema Inodorum Leaf Extract against Plasmodium berghei Infection in Mice.

Malaria is still a serious cause of mortality and morbidity. Moreover, the emergence of malaria parasite resistance to antimalarial drugs has prompted the search for new, effective, and safe antimalarial agents. For this reason, the study of medicinal plants in discovering new antimalarial drugs is important and remains a crucial step in the fight against malaria. Hence, this study is aimed at investigating the antimalarial activity of Gymnema inodorum leaf extract (GIE) in Plasmodium berghei infected mice. Aqueous crude extract of G. inodorum leaves was prepared in distilled water (DW) and acute toxicity in mice was carried out. The antimalarial activity was assessed in the five groups of ICR mice employing the 4-day suppressive and curative tests. Untreated and positive controls were given DW along with 10 mg/kg of chloroquine, respectively. Any signs of toxicity, behavioral changes, and mortality were not observed in mice given GIE up to 5,000 mg/kg. GIE significantly (P < 0.05) suppressed parasitemia by 25.65%, 38.12%, and 58.28% at 10, 50, and 100 mg/kg, respectively, in the 4-day suppressive test. In the curative test, the highest parasitemia inhibition of 66.78% was observed at 100 mg/kg of GIE. Moreover, GIE prevented packed cell volume reduction and body weight loss compared to the untreated control. Additionally, GIE was able to prolong the mean survival time of infected mice significantly. The results obtained in this study confirmed the safety and promise of G. inodorum as an important source of new antimalarial agents and justify its folkloric use for malaria treatment.

Curcuma longa rhizome extract and Curcumin reduce the adhesion of Acanthamoeba triangularis trophozoites and cysts in polystyrene plastic surface and contact lens.

Curcuma longa and Curcumin have been documented to have a wide spectrum of pharmacological effects, including anti-Acanthamoeba activity. Hence, this study sought to explore the anti-adhesion activity of C. longa extract and Curcumin against Acanthamoeba triangularis trophozoites and cysts in plastic and contact lenses. Our results showed that C. longa extract and Curcumin significantly inhibited the adhesion of A. triangularis trophozoites and cysts to the plastic surface, as investigated by the crystal violet assay (P < 0.05). Also, an 80-90% decrease in adhesion of trophozoites and cysts to the plastic surface was detected following the treatment with C. longa extract and Curcumin at 1/2 × MIC, compared to the control. In the contact lens model, approximately 1 log cells/mL of the trophozoites and cysts was reduced when the cells were treated with Curcumin, when compared to the control. Pre-treatment of the plastic surface with Curcumin at 1/2-MIC reduced 60% and 90% of the adhesion of trophozoites and cysts, respectively. The reduction in 1 Log cells/mL of the adhesion of A. triangularis trophozoites was observed when lenses were pre-treated with both the extract and Curcumin. Base on the results obtained from this study, A. triangularis trophozoites treated with C. longa extract and Curcumin have lost strong acanthopodia, thorn-like projection pseudopodia observed by scanning electron microscope. This study also revealed the therapeutic potentials of C. longa extract and Curcumin, as such, have promising anti-adhesive potential that can be used in the management/prevention of A. triangularis adhesion to contact lenses.