Steroids from Diplazium esculentum: Antiplasmodial activity and molecular docking studies to investigate their binding modes

@#Diplazium esculentum is an edible fern commonly consumed by the local community in Malaysia either as food or medicine. Isolation work on the ethyl acetate extract of the stem of D. esculentum resulted in the purification of two steroids, subsequently identified as stigmasterol (compound 1) and ergosterol5,8-endoperoxide (compound 2). Upon further testing, compound 2 displayed strong inhibitory activity against the Plasmodium falciparum 3D7 (chloroquine-sensitive) strain, with an IC50 of 4.27±1.15 µM, while compound 1 was inactive. In silico data revealed that compound 2 showed good binding affinity to P. falciparum-Sarco endoplasmic reticulum calcium-dependent ATPase (PfATP6); however, compound 1 did not show an antiplasmodial effect due to the lack of a peroxide moiety in the chemical structure. Our data suggested that the antiplasmodial activity of compound 2 from D. esculentum might be due to the inhibition of PfATP6, which resulted in both in vitro and in silico inhibitory properties.

Potential of the Ethanol Extract of Aerial Parts of Diplazium esculentum (Retz) SW. AS Larvicide against Anopheles gambiae Giles and Culex quinquefasciatus Say

Plant products have been tested as insecticides against mosquitoes as they are promising candidates to replace conventional insecticides. This study was carried out to evaluate the larvicidalpotential of ethanol extract of the aerial parts of Diplazium esculentumagainst Anopheles gambiaeand Culex quinquefasciatus. Ethanol extract of the aerial parts of D. esculentumwas screened for its phytochemical constituents and used for larvicidal assay. A stock solution of the extract (5g in Original Research Article Umohata et al.; IJTDH, 41(3): 40-47, 2020; Article no.IJTDH.5566841100ml of water) was prepared. From the stock solution, 0.45, 0.60, 0.75, 0.90 and 1.05%w/v concentrations of the extract were obtained for the study. Each concentration of the extract had 3 replicates. The control was also replicated. Twenty (20) third instar larvae each of Anopheles gambiae andCulex quinquefasciatuswere separately exposed to each extract concentration for a duration of 48 hours. Larval nutrient was added to each experimental set up. Observations were made after 24 and 48 hours exposure period.Phytochemical screening revealed the presence of some plant metabolites. Mortality of larvae exposed to the extract increased with increased concentration and exposure time. This study revealed a differential susceptibility of larvae of the two mosquito species to the extract as evident by the 24h LC50values obtained which were 0.355 and 2.468%w/v for An. gambiaeand Cx.quinquefasciatus respectively. Exposure of An. gambiaelarvae to the extract resulted in 100% mortality even with the least concentration of 0.45%w/v after 48 hours exposure period while the highest concentration of extract (1.05%w/v) resulted in 53.33% mortality of Cx.quinquefasciatuslarvae, after an exposure period of 48 hours. Results obtained from this study suggest that the aerial parts of D. esculentumif further explored would be useful in the control of An. gambiae andCx.quinquefasciatus.

In vitro propagation of a rare medicinal fern of Western Ghats – Diplazium esculentum (Reytz.).

Present study aimed for in vitro culture of circinate part of young leaves of D. esculentum which is amongst the leafy vegetables consumed as vegetable by Paniya and Chetti tribes of Western Ghats. The circinate part of young leaves (crosiers), excised before the beginning of foliar expansion, was inoculated on half strength Murashige and Skoog (MS) medium supplemented with auxins indole-3-butyric acid (IBA) or α-napthalene acetic acid (NAA) or 2,4-Dichlorophenoxyacetic acid (2,4-D) and cytokinin 6- benzylaminopurine (BA) in a range 0.5 to 2.5 mg L-1. Combinations of different concentrations of 2,4 D + BA, IBA + BA as well as of NAA+ BA were also tested in half strength MS medium with 3% sucrose and with pH 5.8. The best morphogenic response was obtained with half strength MS medium supplemented with 2,4-D 0.5 mg L-1 and BA 2.5 mg L-1, 3% sucrose, at pH 5.8. For rooting of the microshoots, half strength MS medium supplemented with 2,4-D ( 2 and 1 mg L-1 ) exhibited best results. Present study reports the successful in vitro culturing of D. esculentum.