Antimycobacterial activity of linoleic acid and oleic acid obtained from the hexane extract of the seeds of Mesua ferrea L. and their in silico investigation (original) (raw)

Anti-mycobacterial activity of five plant species used as traditional medicines in the Western Cape Province (South Africa)

Journal of Ethnopharmacology, 2008

Ethnopharmacological relevance: Five plants used in traditional medicine in the Western Cape Province of South Africa, have been investigated for anti-mycobacterial activity: Olea capensis, Tulbaghia alliacea, Dittrichia graveolens, Leysera gnaphalodes and Buddleja saligna. Aim of the Study: The aim was to assess antimycobacterial activity in plants used in treatment of symptoms of TB, and through activity-guided fractionation of extracts to isolate compounds or mixtures with potential as anti-TB drug leads. Materials and Methods: Extracts and derived fractions were assayed against strains of Escherichia coli, Staphylococcus aureus, and Mycobacterium aurum A+. Isolated pure compounds were further tested against Mycobacterium species M. avium ATCC 25291, M. scrofulaceum ATCC 19981, M. microti ATCC 19422 and Mtb H37Rv, and for cytotoxicity against Chinese hamster ovarian cells. Results: Extracts of B. saligna and L. gnaphaloides exhibited significant anti-mycobacterial activity, primarily associated with the presence of non-cytotoxic triterpenoids oleanolic acid in B. saligna and both oleanolic and ursolic acids in L. gnaphaloides. Conclusions: Anti-mycobacterial activity of extracts of selected plants is consistent with their traditional use. The identification of oleanolic and ursolic acids in these plants, and verification of their activity, underlines the potential for exploring structure-activity relationships of derivatives of these ubiquitous triterpenoids.

Potential of plant extracts against Mycobacterium tuberculosis: an integrative review

Peer Review, 2023

Mycobacterium tuberculosis (MTB) is the main cause of tuberculosis. For decades, new forms of treatment and new ways of dealing with the growing resistance acquired by this bacterium to first-line drugs have been studied. Medicinal plants are a source of new bioactive compounds with antimicrobial potential. Objective: to investigate which plant species have already been tested and which main secondary metabolites are active against MTB. Methodology: an integrative review that included in vitro experimental studies, carried out around the world, that used medicinal plant extracts to evaluate the antimycobacterial activity by microdilution, with identification of major compounds, against MTB, between 2011 and 2021, the Web of Science and PubMed were used and the descriptors "medicinal plants AND against AND MTB". Results: 20 species of plants with antimycobacterial activities were found. Four stood out with MIC<10 µg/mL. The variety of secondary metabolites was determinant for antimycobacterial activity, highlighting alkaloids, terpenes and phenolic compounds. Conclusion: the number of secondary metabolites obtained in the extraction is decisive in the antimycobacterial activity.

Quantitative structure-activity relationship of molecules constituent of different essential oils with antimycobacterial activity against Mycobacterium tuberculosis and Mycobacterium bovis

Background Essential oils and their constituents are commonly known for their antibacterial, antifungal and antiparasitic activity, and there are also reports on the antimycobacterial properties, but more experimental data are needed for the description of the mechanism of action or structural (and molecular) properties related to the antimicrobial activity. Methods Twenty-five constituents of essential oils were evaluated against Mycobacterium tuberculosis H37Rv and Mycobacterium bovis AN5 by the Alamar Blue technique. Twenty compounds were modeled using in silico techniques descriptor generation and subsequent QSAR model building using genetic algorithms. The p-cymene, menthol, carvacrol and thymol were studied at the quantum mechanical level through the mapping of HOMO and LUMO orbitals. The cytotoxic activity against macrophages (J774A) was also evaluated for these four compounds using the Alamar Blue technique. Results All compounds tested showed to be active antimicrobials against M. tuberculosis. Carvacrol and thymol were the most active terpenes, with MIC values of 2.02 and 0.78 μg/mL respectively. Cinnamaldehyde and cinnamic acid were the most active phenylpropanes with MIC values of 3.12 and 8.16 μg/mL respectively. The QSAR models included the octanol-water partition (LogP) ratio as the molecular property that contributes the most to the antimycobacterial activity and the phenolic group (nArOH) as the major structural element. Conclusions The description of the molecular properties and the structural characteristics responsible for antimycobacterial activity of the compounds tested, were used for the development of mathematical models that describe structure-activity relationship. The identification of molecular and structural descriptors provide insight into the mechanisms of action of the active molecules, and all this information can be used for the design of new structures that could be synthetized as potential new antimycobacterial agents.

Antimycobacterial evaluation and preliminary phytochemical investigation of selected medicinal plants traditionally used in Mozambique

Journal of …, 2011

Ethnopharmacological relevance: Several medicinal plants are traditionally used in Mozambique to treat tuberculosis and related symptoms. Aims of the study: It was aimed to assess the in vitro antimycobacterial activity of crude extracts from fifteen medicinal plants and to reveal main classes of compounds which may account for the activity of extracts. Methods and materials: The plant materials were sequentially extracted by n-hexane, dichloromethane, ethyl acetate, and 70% ethanol. Decoction of each plant material was also prepared according to traditional use. Broth microdilution method was employed to screen extracts against two mycobacterial species: Mycobacterium smegmatis ATCC 607 and Mycobacterium tuberculosis H37Rv. The extracts with minimum inhibitory concentration(s) (MIC) below 125 g/mL were considered active and further tested against different mycobacterial species and strains, namely Mycobacterium tuberculosis H37Ra, Mycobacterium bovis BCG ATCC 35734, Mycobacterium smegmatis mc 2 155, Mycobacterium avium DSM 44156 and DSM 44157. Cytotoxic effect was evaluated against human macrophages from the monocytic THP-1 cells. Main classes of compounds in these active extracts were proposed from their 1 H NMR spectroscopic characterizations. Results: n-Hexane extracts of Maerua edulis and Securidaca longepedunculata, ethyl acetate extract of Tabernaemontana elegans and dichloromethane extract of Zanthoxylum capense were found to possess considerable activity against Mycobacterium bovis BCG and Mycobacterium tuberculosis H37Ra with MIC 15.6-62.5 g/mL. Tabernaemontana elegans ethyl acetate extract displayed strong activity against Mycobacterium tuberculosis H37Rv (MIC 15.6 g/mL). Except for Tabernaemontana elegans ethyl acetate extract which presented potent cytotoxic effects in THP-1 cells (IC 50 < 4 g/mL), the other three plant extracts showed moderate to none toxicity. Based on 1 H NMR spectroscopic analysis, major components in both Maerua edulis and Securidaca longepedunculata n-hexane extracts were linear chain unsaturated fatty acids. Zanthoxylum capense dichloromethane extract contained more complex constituents (mostly phenolic compounds). In the most potent extract, Tabernaemontana elegans ethyl acetate extract, the prominent compounds were identified as indole alkaloids. Conclusions: The pronounced antimycobacterial activity of the medicinal plants Maerua edulis, Securidaca longepedunculata, Zanthoxylum capense, and Tabernaemontana elegans suggested that they might provide compounds which could be potential anti-TB drug leads.

Isolation of alpha-linolenic acid from Sutherlandia frutescens and its inhibition of Mycobacterium tuberculosis’ shikimate kinase enzyme

BMC Complementary and Alternative Medicine, 2016

Background: Sutherlandia 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. Methods: S. 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. Results: The DCM: MeOH (1:1) extract showed a high percentage inhibition (with an IC 50 of 0.1 μg/ml) of MtbSK and the purified inhibitor was an Alpha-Linolenic Acid (ALA) compound and it had a significant IC 50 of 3.7 μg/ml. Conclusions: This study demonstrated that ALA from S. frustescens is an inhibitor of shikimate kinase a good drug target for M. tuberculosis.

Composition of three essential oils, and their mammalian cell toxicity and antimycobacterial activity against drug resistant-tuberculosis and nontuberculous mycobacteria strains

Natural product communications, 2011

Tuberculosis (TB) is the most ancient epidemic disease in the world and a serious opportunistic disease in HIV/AIDS patients. The increase in multidrug resistant Mycobacterium tuberculosis (MDR-TB, XDR-TB) demands the search for novel antimycobacterial drugs. Essential oils (EOs) have been widely used in medicine and some EOs and their major components have been shown to be active against M. tuberculosis. The aim of this work was to evaluate the antimycobacterial and cell toxicity activities of three EOs derived from Salvia aratocensis, Turnera diffusa and Lippia americana, aromatics plants collected in Colombia. The EOs were isolated by hydrodistillation and analyzed by GC/MS techniques. The EOs were tested against 15 Mycobacterium spp using a colorimetric macrodilution method and against mammalian Vero and THP-1 cells by MTT. The activity was expressed as minimal concentration in microg/mL that inhibits growth, and the concentration that is cytotoxic for 50 or 90% of the cells (CC...

Evaluation of Some Plant-derived Secondary Metabolites Against Sensitive and Multidrug-resistant Mycobacterium tuberculosis

The results on the bioevaluation of thirty five plant-derived secondary metabolites against one sensitive and three multidrugresistant clinical isolates of Mycobacterium tuberculosis are reported. Results toward the sensitive strain showed that five products gave MIC values of 12.5 µg/mL: the alkaloids 6-methoxydihydrochelerytrine (2) and 6-methoxy-dihydrochelirubine (6), the flavanone pinostrobin (17), 1-hydroxy-benzoisochromanquinone (23) and 23-hydroxy-5a-lanosta-7,9(11),24-triene-3-one (33). These were followed by the peracetylstrictosidine lactam (12) and the quinone aloe-emodin (24) which displayed MICs of 6.25 µg/mL. Finally, liriodenine (8) was the most active (MIC: 3.125 µg/mL) of all secondary metabolites. Results with the multidrug-resistant clinical isolates showed that 6-methoxy-dihydrochelirubine (6) was the most active (MIC: 12.5 µg/mL).

Preliminary antimycobacterial study on selected Turkish plants (Lamiaceae) against Mycobacterium tuberculosis and search for some phenolic constituents

BMC Complementary and Alternative Medicine, 2013

Background: The global resurgence of tuberculosis is a significant threat. Lamiaceae members have been used in folk remedies for centuries. This study was designed to assess the in-vitro antimycobacterial activity of eighteen crude extracts from six plants (Lamiaceae) and to characterize their phenolic and flavonoid compounds. Methods: Six Turkish medicinal plants of the family Lamiaceae (Stachys tmolea Boiss., Stachys thirkei C. Koch, Ballota acetabulosa (L.) Benth., Thymus sipthorpii Benth., Satureja aintabensis P.H. Davis, and Micromeria juliana (L.) Benth. ex Reich.) were collected in 2009-2010. Dried and crushed plant samples were subjected to sequential extraction with petroleum ether, ethyl acetate, and methanol in order of increasing polarity. A broth microdilution method was employed to screen extracts against four mycobacterial strains of Mycobacterium tuberculosis. Phenolic and flavonoid compounds were characterized by liquid chromatography-mass spectrometry. Results: S. aintabensis, T. sibthorpii, and M. juliana were found to develop considerable activity against the four strains of M. tuberculosis with the minimal inhibitory concentrations value of 12.5-100 μg/ml. S. aintabensis and T. sibthorpii extracts killed M. tuberculosis with the minimum bactericidal concentration value of 50-800 μg/ml. On the basis of these prominent antimycobacterial activity, we suggest that they could be a source of natural anti-tuberculosis agents. Conclusion: S. aintabensis and T. sibthorpii showed activity by killing Mycobacteria strains. The major phenolic compound was rosmarinic for T. sibthorpii and S. aintabensis. Flavonoids might be "a modal" for the drug design.

Comparative Anti-mycobacterial Activity on Lowenstein-Jensen Slants of Selected Medicinal Plants Used in the Congolese Pharmacopeia

Journal of Diseases and Medicinal Plants

Tuberculosis is an infectious disease that kills approximately three million people annually worldwide. The emergence of multidrug resistant, extensively drug resistant and lengthy therapy reduces the patient compliance and therefore comprises control strategies. In this study, the leaves of Terminalia ivorensis, Carapa procera, Fagara macrophylla, Anacardium occidentale, Ficus spp. and Drepanoalpha® (a polyherbal medicine to relieve sickle cell anaemia) were extracted with petroleum ether, ethyl acetate and methanol in order to screen potential bioactive compounds in different extracts and to assess their anti-mycobacterial activity against Mycobacterium tuberculosis H37Rv and Mycobacterium tuberculosis spp. on Lowenstein-Jensen medium using a qualitative approach. The activity was determined as to whether there was growth or not. It was shown that only the methanolic extract displayed a good activity on both strains than the petroleum ether and ethyl acetate extracts. The presence of phytochemicals in plants such as alkaloids, flavonoids, tannins, saponins, anthocyanins and quinones known to be of medicinal importance pointed out a possible source for anti-mycobacterial agents to address the problem of multidrug resistance. The in vitro findings of this study provide a partial support for the use of these plants in the control of various infectious diseases as lead to drug discovery and should be reiterated and recommended for a clinical trial using an animal model.