Botanical studies, antimicrobial activity and cytotoxity of Eleutherine bulbosa (Mill.) Urb

Abstract

The use bulbs of Eleutherine bulbosa for treatament of diseases caused by malaria, amoeba and bacteria. This study accomplished the botanical and phytochemical characterization, antimicrobial activity and cytotoxic of E. bulbosa. For the anatomical studies, the studied material was fixed in formaldehyde – acetic acid and ethanol and it was dyed in safranin and in astra blue. For histochemistry, was fixed in buffered neutral formalin and in ferrous sulphate in formalina. Ethanolic Extract (EE) was submitted to fractionation in a chromatographic column and four (4) fractions were obtained from it. The Dichloromethane Fraction (DF) was submitted to a new fractionation. The biological activity was evalueted by diffusion in agar, microdilution and celular viability MTT. The bulb of E. bulbosa is characterized by a reduced caulinar axis and by succulent amiliferous cataphylls, epidermis with the presence of anthocyanins, homogeneous mesophyll with idioblasts of prismatic crystals of calcium oxalate and phenolic compounds. In agar diffusion it was observed that EE, DF and ethyl acetate fraction (ACF) were active for Staphylococcus aureus. In microdilution, DF (Inhibitory minimum concentration= 125 µg/ mL) was more active. For all samples the Minimous Bactericidal Concentration was >1000 µg/ mL. The fractionation contributes positively with the citotoxicity, being subfractions S1 and S2 the most citotoxic ones. The Fraction Dichloromethane was the most active one for S. aureus and more citotoxicity to VERO cells. Probably the less citotoxicity of EE is related to the presence of anthocyanins that are present on bulbs epidermis.

Anti-leishmanial activity of Eleutherine plicata Herb. and predictions of isoeleutherin and its analogues

“…From the ethanolic extract (EEEp; yield 2.84%) the following fractions were obtained: hexane (FHEp; yield 3.1%), dichloromethane (FDEp; yield 19.6%), ethyl acetate (FAEEp; yield 10.2%) and methanol (FMEp; 61.9% yield). Isoeleutherin was isolated from FDEp and its identification is described by Borges et al (2020) .…”

Toxicity evaluation of Eleutherine plicata Herb. extracts and possible cell death mechanism

“…After 48 h of treatment, isoeleutherin and FDMEp were more cytotoxic than the ethanol extract. The biological activities of E plicata have been attributed to quinonic compounds [ 26 , 27 , 47 ]. It is believed that it is an intrinsic property of these compounds associated with other structural factors, such as resonance effects, that may contribute to cytotoxicity.…”

“…In the microdilution test, the most promising sample was FDMEp (minimum inhibitory concentration = 125 μg/mL). For all samples, the Minimum Bactericidal Concentration was > 1000 μg/mL [ 26 ].…”

Study of Genotoxicity, Activities on Caspase 8 and on the Stabilization of the Topoisomerase Complex of Isoeleutherin and Analogues

“…The following compounds have already been isolated from this species: isoeleutherin ( Figure 1 A), eleutherin ( Figure 1 B), eleutherol ( Figure 1 C), eleutherinone ( Figure 1 D), (R)-4-Hydroxyeleutherine ( Figure 1 E), eleuthrone ( Figure 1 F), isoeleuthoside C ( Figure 1 G) and eleutherinol-8-O-b-D-glucoside ( Figure 1 H) [ 2 , 6 , 7 , 8 ]. Some studies demonstrated the activity of extracts, fractions and/or isolated substances from E. plicata against malaria parasites [ 7 ] and as antimicrobial [ 9 ] and antitumor agents [ 10 ]. Pharmacological activities have been related to quinone compounds, especially isoeleutherin [ 7 , 10 ].…”