Antibacterial activities of the methanol extracts of ten Cameroonian vegetables against Gram-negative multidrug-resistant bacteria

Abstract

BackgroundMany edible plants are used in Cameroon since ancient time to control microbial infections. This study was designed at evaluating the antibacterial activities of the methanol extracts of ten Cameroonian vegetables against a panel of twenty nine Gram negative bacteria including multi-drug resistant (MDR) strains.MethodsThe broth microdilution method was used to determine the Minimal Inhibitory Concentrations (MIC) and the Minimal Bactericidal Concentrations (MBC) of the studied extracts. When chloramphenicol was used as a reference antibiotic, the MICs were also determined in the presence of Phenylalanine-Arginine β-Naphtylamide (PAβN), an efflux pumps inhibitor (EPI). The phytochemical screening of the extracts was performed using standard methods.ResultsAll tested extracts exhibited antibacterial activities, with the MIC values varying from 128 to 1024 mg/L. The studied extracts showed large spectra of action, those from L. sativa, S. edule, C. pepo and S. nigrum being active on all the 29 bacterial strains tested meanwhile those from Amaranthus hybridus, Vernonia hymenolepsis, Lactuca.carpensis and Manihot esculenta were active on 96.55% of the strains used. The plant extracts were assessed for the presence of large classes of secondary metabolites: alkaloids, anthocyanins, anthraquinones, flavonoids, phenols, saponins, steroids, tannins and triterpenes. Each studied plant extract was found to contain compounds belonging to at least two of the above mentioned classes.ConclusionThese results confirm the traditional claims and provide promising baseline information for the potential use of the tested vegetables in the fight against bacterial infections involving MDR phenotypes.

Chemical composition, antibiotic promotion and in vivo toxicity of Piper nigrum and Syzygium aromaticum essential oil

“…Clove (Syzygium aromaticum) is an aromatic herb that has many useful purposes. Its essential oil has demonstrated several properties as reported by Noumedem et al (2013). S. aromaticum is widely cultivated in Indonesia, Sri Lanka, Madagascar, Tanzania and Brazil.…”

“…Black pepper (Piper nigrum) has many medicinal properties among which, antibacterial, antifungal, antiinflamatory and antidiarrhoeal are mostly reported (Noumedem et al, 2013). Clove (Syzygium aromaticum) is an aromatic herb that has many useful purposes.…”

“…In the same report, Salmonella Typhi was recognized as one of the major cause of food borne diseases. Regarding Staphylococcus aureus, Tong et al (2015) stated that in the industrialized world, the population incidence of S. aureus bacteremia ranges from 10 to 30 per 100,000 person/year.Black pepper (Piper nigrum) has many medicinal properties among which, antibacterial, antifungal, antiinflamatory and antidiarrhoeal are mostly reported (Noumedem et al, 2013). Clove (Syzygium aromaticum) is an aromatic herb that has many useful purposes.…”

Antimicrobial, Antiviral Activity and GC-MS Analysis of Essential Oil Extracted from Achillea fragrantissima Plant Growing In Sinai Peninsula, Egypt

“…Natural products of higher plants may possess a new source of antimicrobial agents with possibly novel mechanisms for treatment of infectious diseases [8,9]. Medicinal plants contain active principles which can be used as alternative effective herbal drugs against common bacterial infections [10].…”

“…Although, the pharmacological companies have produced a number of new antibiotics recently, but even then microorganism resistance to antibiotics increased throughout the world [5,7]. This situation has attract attention of researchers towards herbal products for developing and improve the antibacterial drugs quality [6,7].Natural products of higher plants may possess a new source of antimicrobial agents with possibly novel mechanisms for treatment of infectious diseases [8,9]. Medicinal plants contain active principles which can be used as alternative effective herbal drugs against common bacterial infections [10].…”