BackgroundSutherlandia frutescens (L) R.Br. is one of traditional herbal medicines that formed the basis of primary health care systems since the earliest days and is still widely used. Sutherlandia is prescribed for people with tuberculosis (TB), but is still not known which compound(s) acts against M. tuberculosis and its mode of action. The aim of this study was to identify and isolate antimycobacterial compounds from S. frutescens extracts against shikimate kinase, a drug target for M. tuberculosis.MethodsS. frutescens were dried, ground and extracted with ethanol, dichloromethane: methanol and water. Fractionation and separation of compounds was done with column chromatography. Chromatograms were developed in butanol/acetic acid/water (BAW) [21:6:3]; chloroform/methanol/water/formic acid (CMWF1) [60:15:2:1] and (CMWF2) [21:9:1:0.3]. Separation and isolation of active compounds were done using preparative HPLC. The activity of the plant extracts were also screened against shikimate kinase enzyme (MtbSK) using the MtbSK inhibition assay.ResultsThe DCM: MeOH (1:1) extract showed a high percentage inhibition (with an IC50 of 0.1 μg/ml) of MtbSK and the purified inhibitor was an Alpha-Linolenic Acid (ALA) compound and it had a significant IC50 of 3.7 μg/ml.ConclusionsThis study demonstrated that ALA from S. frustescens is an inhibitor of shikimate kinase a good drug target for M. tuberculosis.

Sutherlandia frutescens (L) R. Br. bevat verskeie essensiële bioaktiewe verbindings met farmakologiese aktiwiteit waarvoor daar kliniese bewyse bestaan. Sutherlandia word vir mense met tuberkulose voorgeskryf, maar niemand weet nog watter verbindings in hierdie plant Mycobacterium tuberculosis en die werking daarvan teenwerk nie. Hierdie studie het ten doel om te bepaal of S. frutescens antimikobakteriese verbindings bevat. Bogrondse dele van S. frutescens is gedroog, gemaal en met etanol:metanol [1:1] (vol./vol.) en water onttrek. Die chemiese profiel is bepaal deur hoëverrigting vloeistofchromatografie-massaspektrometrie en dunlaag-chromatografie te gebruik. Die dunlaagchromatografie is in butanol:asynsuur:water (BAW) [21:6:3], chloroform:metanol:water:mieresuur (CMWM1) [60:15:2:1] en CMWM2 [21:9:1:0.3] ontwikkel. Die kwalitatiewe anti-oksidant-aktiwiteit is bepaal deur 2.2 difeniel-2-pikrielhidrasiel (DFPH) te gebruik. Die antimikobakteriese aktiwiteit van die plantekstrakte is bepaal deur mikro-verdunning en bio-outografiese metodes teen Mycobacterium smeagmatis te gebruik. Ons het lae antimikobakteriese aktiwiteit teen M. smegmatis in die bio-outogramme waargeneem. Die profiele van die hoëverrigting vloeistofchromatograpfie-massaspektrometrie het meer verbindings in die etanolekstrakte as in die waterekstrakte aangedui. Die gemiddelde waardes vir minimum inhibeerderkonsentrasie vir al die ekstrakte was 0.61 mg/mL. Die DCM:MeOH (1:1) ekstrak het die laagste minimum inhibeerderkonsentrasie-waarde, naamlik 0.28 mg/mL gehad. Die resultate het getoon dat die plant verder vir moontlike antimikobakteriese agente ondersoek kan word. Lae aktiwiteit is waargeneem, waarskynlik as gevolg van stadig vermeerderende bacilli en nie-vermeerderende organismes. Die studie bied voorlopige wetenskaplike ondersteuning vir die tradisionele medisinale gebruik van hierdie plant. Navorsing korrelasie: Hierdie artikel is die vertaalde weergawe en is beskikbaar gestel om ‘n breër lesersgroep te bereik. Die oorspronklike Engelse artikel is beskikbaar hier: https://doi.org/10.4102/satnt.v36i1.1486

Sutherlandia frutescens (L) R. Br. contains several essential, bioactive compounds with clinically proven pharmacological activities. Sutherlandia is prescribed for people with tuberculosis but it is still not known what compounds in this plant act against Mycobacterium tuberculosis and its mode of action. This study is aimed at determining if S. frutescens extracts contain antimycobacterial compounds. Aerial parts of S. frutescens were dried, ground and extracted with ethanol, dichloromethane: methanol 1:1 (v/v) and water. The chemical profiling was done using high-performance liquid chromatography-mass spectroscopy (HPLC-MS) and thin layer chromatography (TLC). TLC plates were developed in butanol:acetic acid:water (BAW) to the ratio of 21:6:3; chloroform:methanol:water:formic acid (CMWF1) [60:15:2:1] and (CMWF2) [21:9:1:0.3]. Qualitative antioxidant activity was done, using 2.2-diphenylpacryl-1-hydrazyl (DPPH). Antimycobacterial activity of the plant extracts was evaluated, using micro-dilution and bioautographic methods against Mycobacterium smegmatis. Low antimycobacterial activity against M. smegmatis was observed on the bioautograms. The ethanol extracts contained more compounds compared to water extracts on HPLC-MS chromatographic profiles. The average Minimum Inhibitory Concentration (MIC) values for all the extracts were 0.61 mg/mL units and the DCM:MeOH (1:1) extract had the lowest MIC value of 0.28 mg/mL. The results showed that the plant could be further explored for possible antimycobacterial agents. Low activity was observed, possibly due to low replication of bacilli and non-replicating organisms. The study provides preliminary scientific validation of the traditional medicinal use of this plant. Further studies are required to identify the bioactive compounds in the DCM:MeOH 1:1 extract which showed significant antimycobacterial activities. Research correlation: This article is the original version, of which an Afrikaans translation was made available to provide access to a larger readership, available here: https://doi.org/10.4102/satnt.v36i1.1494