Antibacterial activities of the methanol extracts of seven Cameroonian dietary plants against bacteria expressing MDR phenotypes

Abstract

The morbidity and mortality caused by bacterial infections significantly increased with resistance to commonly used antibiotics. This is partially due to the activation of efflux pumps in Gram-negative bacteria. The present work designed to assess the in vitro antibacterial activities of seven Cameroonian dietary plants (Sesamum indicum, Sesamum radiatum, Cinnamomum zeylanicum, Corchous olitorius, Cyperus esculentus, Adansonia digitata, Aframomum kayserianum), against multidrug resistant (MDR) Gram-negative bacteria over expressing active efflux pumps. The standard phytochemical methods were used to detect the main classes of secondary metabolites in the extracts. The antibacterial activities of the studied extracts in the absence or presence of an efflux pump inhibitor (PAβN) were evaluated using liquid microbroth dilution method. The results obtained indicated that apart from the extract of C. esculentus, all other samples contained alkaloids, phenols and polyphenols meanwhile other classes of chemicals were selectively present. The studied extracts displayed antibacterial activities with minimal inhibitory concentrations (MICs) values ranged from 64 to 1024 μg/mL on the majority of the 27 tested microbial strains. The extract of S. indicum was active against 77.77% of the tested microorganisms whilst the lowest MIC value (64 μg/mL) was recorded with that of A. kayserianum against E. aerogenes EA294. The results of the present work provide baseline information on the possible used of the tested Cameroonian dietary plants in the treatment of bacterial infections including multi-drug resistant phenotypes.

The 15-lipoxygenase inhibitory, antioxidant, antimycobacterial activity and cytotoxicity of fourteen ethnomedicinally used African spices and culinary herbs

“…Cinnamomum verum Bark Spices, respiratory, digestive and gynaecological ailments (Ranasinghe et al, 2012) bark anti-inflammatory, antioxidant, antibacterial, collagenase, urease inhibitory ( Bujnakova et al, 2013;Hong et al, 2012;Seukep et al, 2013). Corchorus olitorius (Tiliaceae) 14725/SRFC Indian jute, Jew's mallow.…”

“…Antioxidant, antibacterial, antiinflammatory (Biradar et al, 2010;Jing et al, 2013;Seukep et al, 2013). (Lin et al, 2001;Olaleye, 2007) Leaves Antibacterial , α-glucosidase and α-amylase inhibitory, antidiabetic Salehi et al, 2013;Saxena et al, 2011).…”

“…(Lin et al, 2001;Olaleye, 2007) Leaves Antibacterial , α-glucosidase and α-amylase inhibitory, antidiabetic Salehi et al, 2013;Saxena et al, 2011). (Bruneton, 1999) Roots Antibacterial, spermatotoxicity, cytotoxicity, genotoxicity, insecticidal, antioxidant, (Akinboro and Bakare, 2013;Djeussi et al, 2013;Koubala et al, 2013;Oriakhi et al, 2014 (Bopitiya and Madhujith, 2013;Seukep et al, 2013;Sharif et al, 2013). Bankole et al, 2007).…”

“…Seeds Hypoglycaemia, antimicrobial (Bankole et al, 2007;Seukep et al, 2013). (Feussner and Wasternack, 2002).…”

Evaluation of antibacterial effect of Cyperus species on typical food-borne pathogens

“…The extracts were serially diluted to give a concentration of 666, 333, 166.5, 50, 83.25, 41.62, 20.81, 10.40 and 5.25 mg/mL [24]. Then, 100 µL of each concentration was added in a well (96-well microplate) containing 95 µL of MHB and 5 µL of inoculum (1.5 × 10 6 CFU/mL) [25]. The microplate was incubated at (37 ± 1) °C for 24 h. Dilution of the extract corresponding to respective test organism showing no visible growth was considered as MIC [4] to determine MBC.…”