Novel Piperine compound AB05 (N-5-(3,4-dimethoxyphenyl) -2E,4E pentadienylpiperidine) inhibits H1N1 influenza virus propagation in vitro

@# Pandemic H1N1 influenza virus respiratory illness has become an inevitable global health concern. With antigenic drift, it becomes necessary to have drugs over tailor-made HIN1 vaccine every year. In the current study, we screened many Piperine derivative in which, N-5-(3,4-dimethoxyphenyl)-2E,4E-pentadienylpiperidine (AB05) and was further studied for anti-H1N1influenza virus activity and compared with other stains in-vitro on MDCK cell line. Initial cytotoxic doses of AB05 for the MDCK cell line were > 25µM. The results showed a dose-dependent reduction of the viral plaque’s in the adsorption assay with EC50 of 0.33 µM. The mechanism of AB05 was by inhibition of matured viral release as evaluated by the time of virus addition with incubation of 6-10 hours. With the promising H1N1 virucidal activity of AB05, we included various strains of human influenza virus to screen AB05 inhibition of Neuraminidase (NA). The result showed 70% NA inhibition in WSN (H1N1), 90% in H3N2 & Influenza B and 49% in Tamiflu resistant H1N1). Further our In silco docking studies substantiated experimental results by showing the difference in binding and cooperation between H1N1 and N3N2. Together these observations illustrate that Piperine derivative AB05 is a promising lead molecule which needs further evaluation in animal models.

Novel Piperine compound AB05 (N-5-(3,4-dimethoxyphenyl) -2E,4E pentadienylpiperidine) inhibits H1N1 influenza virus propagation in vitro.

Pandemic H1N1 influenza virus respiratory illness has become an inevitable global health concern. With antigenic drift, it becomes necessary to have drugs over tailor-made HIN1 vaccine every year. In the current study, we screened many Piperine derivative in which, N-5-(3,4-dimethoxyphenyl)-2E,4E-pentadienylpiperidine (AB05) and was further studied for anti-H1N1influenza virus activity and compared with other stains in-vitro on MDCK cell line. Initial cytotoxic doses of AB05 for the MDCK cell line were > 25µM. The results showed a dose-dependent reduction of the viral plaque's in the adsorption assay with EC50 of 0.33 µM. The mechanism of AB05 was by inhibition of matured viral release as evaluated by the time of virus addition with incubation of 6-10 hours. With the promising H1N1 virucidal activity of AB05, we included various strains of human influenza virus to screen AB05 inhibition of Neuraminidase (NA). The result showed 70% NA inhibition in WSN (H1N1), 90% in H3N2 and Influenza B and 49% in Tamiflu resistant H1N1). Further our In silco docking studies substantiated experimental results by showing the difference in binding and cooperation between H1N1 and N3N2. Together these observations illustrate that Piperine derivative AB05 is a promising lead molecule which needs further evaluation in animal models.

In vitro anti-yeast activity of chloramphenicol: A preliminary report.

Chloramphenicol is a bacteriostatic antimicrobial agent but its antifungal activity is not known. The present study aimed to investigate the activity of chloramphenicol against 30 representative yeasts. The antimicrobial assay of chloramphenicol (50mg/mL; 100mg/mL and 200mg/mL) was determined by the disc diffusion method using Mueller-Hinton agar against 30 representative yeast strains. Zone of inhibition was read after 48-72h incubation at 37°C and results were compared with some standard antifungal agents. Most of the tested yeasts (73.3%) showed inhibition zones (5 up to 35mm) to chloramphenicol impregnated discs (200mg/mL). Three out of the four tested Candida albicans as well as Candida famata, Candida glabrata, Candida haemolonei and Cryptococcus neoformans showed no inhibition zones to chloramphenicol (200mg/mL). Caspofungin acetate (50mg/mL) inhibited 83.3% of the strains; ketoconazole (200mg/mL) 70% and metronidazole 10%. Chloramphenicol discs: 50 and 100mg/mL showed less activity (6.7% and 36.7%, respectively) compared to the 200mg discs; whereas chloramphenicol (BBL; 3µg/mL) inhibited 13.3% of the strains. The anti-yeast activities of chloramphenicol were comparable to other known antifungal compounds. Moreover, it is cheap, has fewer side effects and its inclusions in selective fungal media such as Mycosel have to be questioned.