Screening of Elaeocarpus floribundus fruit extracts for bioactive phytocomponents and antibacterial activity against food-borne bacteria

Abstract

Background: Medicinal plants possess several active components having antimicrobial activity. This study was undertaken to explore the antibacterial activity of Indian olive, Elaeocarpus floribundus, fruit extracts against potential food-borne bacterial isolates.Methods: The ethanolic extracts of olive seed (OSE) and mesocarp-epicarp (OMeE), and the aqueous extracts of olive seed (AqOSE) and mesocarp-epicarp (AqOMeE) were prepared, and analysed qualitatively for phytochemicals. The antibacterial activity of the extracts against food-borne pathogenic bacteria: Bacillus sp., Bacillus cereus, Enterococcus sp. and Corynebacterium sp., was determined by agar-well diffusion method, and minimum inhibitory concentration (MIC) values by agar dilution method.Results: The concentration dependent activity of the extracts against the bacteria was recorded with zone diameter of inhibition 6 - 28 mm for ethanolic extracts, and 7 - 23 mm for aqueous extracts. The ethanolic extracts were confirmed positive for the presence of cardiac glycosides, anthraquinone glycosides, steroids, terpenoids and quinones, while cardiac glycosides, anthraquinone glycosides, steroids, terpenoids, quinones and phenol were detected in the aqueous extracts. The MICs of OSE and OMeE ranged 9.375-12.5mg/ml, and 1.875 - 3.125 mg/ml, respectively, for the test bacteria.Conclusions: The olive fruit extracts contained various bioactive components, and had excellent antibacterial activity against food-borne bacteria. The plant might be useful in the preparation of non-antibiotic antibacterial agents and in the storage of food as well.

Indian olive, Elaeocarpus floribundus fruits in combating MRSA infection

“…floribundus fruit were prepared according to the method mentioned earlier [7], and tested against MRSA by agar well diffusion method [1] using nutrient agar medium (Hi-Media, India). The ZDI (nearest whole) on the test agar plate, around each of the wells, due to the antimicrobial action of the extracts at various concentrations (2.49, 4.15 and 8.3 mg/well), was measured and interpreted following the criteria mentioned earlier [1].…”

“…The olive extracts are natural sources of reducing as well as stabilizing agents for the synthesis of silver nanoparticles with antibacterial activity against spoilage and pathogenic bacteria, such as Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa [6]. It has been reported that the ethanolic as well as aqueous extracts of seed and mesocarp-epicarp of olive (E. floribundus) fruits had growth inhibitory activity against food-borne bacteria [7]. However, no scientific report has been made on anti-methicillin resistant …”

Phytochmical analysis and antibacterial property assessment of helencha (Enhydra fluctuans; Family: Asteraceae) extracts

“…The plants were washed repeatedly, cut into pieces and dried under shade for two weeks. The dried plant materials were milled to form fine powder, and were processed to prepare the aqueous extract of E. fluctuans (AEE) and methanolic extract of E. fluctuans (MEE), as described earlier [6,7]. For the preparation of MEE, 5 g of sample powder was soaked in 50 ml methanol for 72 h with manual shaking at 2 h intervals, and in order to prepare AEE, 5 g of the powdered E. fluctuans was boiled in a conical flask containing 50 ml double distilled water, for 30 min, without pressure.…”

“…The bioactive components, such as flavonoids, steroids, terpenoids, quinone, phenol, cardiac glycosides, anthraquinone glycosides and saponins, present in the plant extracts have been detected qualitatively, following the protocol mentioned elsewhere [6,8].…”

High Performance Liquid Chromatography Analysis and Anti-Methicillin Resistant Staphylococcus Aureus Activity of Olive Fruit Ethanolic Extract

“…The seeds and mesocarp-epicarp parts of the fruits were separated, sheddried, and thereafter (mesocarp-epicarp parts and seeds) were grinded. The ethanolic extracts of the grinded materials (25 g in 200 ml) were prepared as described earlier 29,30 . The olive seed ethanolic extract (OSE; 125 μg/μl)) as well as the olive mesocarp-epicarp ethanolic extract (OME; 125 μg/μl), after filtration, were stored at 4⁰C, for further work.…”