ABSTRACT Objective: Costus pictus D. Don is a traditionally used plant in Naojan area of Golaghat district of Assam, India specifically for treating diabetes. Six compounds were isolated from standardized methanolic extract of the aerial parts (MECP). The prime objective was to select most potent antidiabetic compounds among the isolated compounds viz. F67, F12, F16, F3032, F37 & F48 by using in vitro and in vivo methods. Methods: Isolated compounds were subjected to initial screening by in vitro α-amylase inhibition activity assay using iodine-starch and DNSA (3,5-dinitrosalicylic acid) methods. Compounds depicting promising in vitro activity were selected for in vivo Streptozotocin (STZ) induced antidiabetic screening activity. Then based on the in vivo results, most potent compounds were selected for instrumental characterization by Q-TOF ESI-MS, 1HNMR, 13CNMR & FTIR. Results: Amongst the six compounds isolated from MECP, three compounds viz. F12, F16 & F48 showed potent in vitro activity. They were subsequently subjected to evaluation of the antidiabetic activity in vivo by oral administration, at dose of 10, 20 & 50 mg/kg body weight respectively, using Wister rat (120-150 g) and Glibenclamide (10mg/k body weight) as standard. Two compounds, F12 and F48 at dose of 50 mg/kg body weight, reversed STZ induced diabetic parameters (increased blood glucose level, altered plasma profile and histoarchitecture of the pancreatic and hepatic cells) with statistical significance (P<0.05), that was comparable with the standard. Hence, instrumental characterization by Q-TOF ESI-MS, 1HNMR, 13CNMR & FTIR of compounds F12 and F48 isolated from MECP was carried out which established their identity as (3,5,7-Trihydroxy-3’-hydroxy-4’-methoxy) flavanone or [3,5,7-Trihydroxy-2-(3’-hydroxy-4’-methoxy phenyl)-2,3-dihydrochromen-4-one] and 3,5,8-trihydroxy-7-methoxy-2-phenyl-2,3-dihydrochromen-4-one or [7-methoxy-3, 5, 8 trihydroxy flavanone] respectively. Conclusion: The study culminated in elucidation of two flavanones as most potent compounds in exhibiting antidiabetic activities. The findings were thus successful in validating the traditional practices in Golaghat district of Assam, India, associated with the use of Costus pictus D. Don in the treatment of diabetes.

RESUMEN Objetivo: Costus pictus D. Don es una planta usada tradicionalmente en la zona del distrito de Golaghat Naojan de Assam, India específicamente para el tratamiento de la diabetes. Seis compuestos se aislaron a partir de extracto metanólico estandarizados de las hojas (MECP). El principal objetivo fue seleccionar compuestos antidiabéticos más potentes entre los compuestos aislados viz. F67, F12, F16, F3032, F37 y F48 mediante métodos in vitro e in vivo. Métodos: Los compuestos aislados fueron sometidos a cribado inicial mediante ensayo de actividad de inhibición in vitro α-amilasa utilizando yodo-almidón y métodos DNSA (ácido 3,5-dinitrosalicilico). Los compuestos que presentaban una actividad in vitro prometedora se seleccionaron para la actividad de cribado antidiabético inducida por estreptozotocina (STZ) in vivo. En función de los resultados in vivo, la mayoría de los compuestos potentes se seleccionaron para la caracterización instrumental por Q-TOF ESI-MS, 1HNMR, 13CNMR y FTIR. Resultados: Entre los seis compuestos aislados de MECP, tres compuestos viz. F12, F16 y F48 mostraron una potente actividad. Posteriormente se sometieron a evaluación de la actividad antidiabética in vivo mediante administración oral, en dosis de 10, 20 y 50 mg / kg peso, utilizando ratas Wister (120-150 g) y glibenclamida (10 mg / kg peso) como estándar. Dos compuestos, F12 y F48 en dosis de 50 mg/kg peso, revirtieron los parámetros diabéticos inducidos por STZ (aumento del nivel de glucosa en sangre, plasma perfil alterado y histoarquitectura del páncreas y células hepáticas), con significación estadística (P<0,05) que era comparable con la norma. Se llevo a cabo la caracterización instrumental por Q-TOF ESI-MS, RMN 1H, RMN 13C y FTIR de los compuestos F12 y F48 aislado de MECP, lo que estableció su identidad como (3,5,7-trihidroxi-3 ‘-hidroxi-4’- metoxi) flavanona o [3,5,7-trihidroxi-2- (fenil 3 ‘-hidroxi-4’-metoxi) -2,3-dihydrochromen-4-ona] y 3,5,8-trihidroxi-7-metoxi -2-fenil-2,3-dihydrochromen-4-ona o [7-metoxi-3, 5, 8 trihidroxi flavanona] respectivamente. Conclusión: El estudio culminó en la elucidación de dos flavanonas como los compuestos más potentes en la exposición de actividades antidiabéticas. Los resultados lograron validar las prácticas tradicionales en el distrito de Golaghat de Assam, India, asociados con el uso de Costus pictus D. Don en el tratamiento de la diabetes.

ABSTRACT The receptor protein PfATP6 has been identified as the common target of artemisinin and curcumin. The work was initiated to assess the antimalarial activity of six curcumin derivatives based on their binding affinities and correlating the in silico docking outcome with in vitro antimalarial screening results. A ligand library of thirty two Knoevenagel condensates of curcumin were designed and docked against PfATP6 protein and six compounds with the best binding scores were synthesized and screened for their antimalarial activity against the sensitive 3D7 strain of Plasmodium falciparum. ADME/Tox, pharmacokinetic and pharmacodynamic profiles of the designed compounds were analyzed and reported. 4-FB was found to have similar binding energy to the standard artemisinin (-6.75 and -6.73 respectively) while 4-MB, 3-HB, 2-HB, B, 4-NB displayed better binding energy than curcumin (-5.95, -5.89, -5.68, -5.35, -5.29 and -5.25 respectively). At a dose of 50 µg/mL all the six compounds showed 100% schizont inhibition while at 5µg/ml, five showed more than 75% inhibition and better results than curcumin. 4-FB showed the best activity with 97.8% schizonticidal activity. The in vitro results superimpose the results obtained from the in silico study thereby encouraging development of promising curcumin leads in the battle against malaria.