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.

The current study explores the antibacterial activity and HPLC (high performance liquid chromatography) profiles of olive (Elaeocarpus floribundus) fruits. The ethanolic extract of olive fruit parts: seed (OSE) and mesocarp-epicarp (OME), were prepared, and tested for their antibacterial activity, by agar-well diffusion method using 1.875 -6.25 mg/well, against the clinical isolates of methicillin resistant Staphylococcus aureus (MRSA; n=3). The HPLC profiles of the extracts were prepared. For the test MRSA isolates, the OSE, at concentrations 1.875, 3.125 and 6.25 mg/well, had ZDI (zone diameter of inhibition) values 8  1.73 mm (range: 6 -9 mm), 9  1.73 mm (range: 7 -10 mm) and 11.67  1.53 mm (range: 10 -13 mm), respectively, and the ZDIs for OME recorded were 12.33  2.51 mm (range: 10 -15 mm), 13.66  2.08 mm (range: 12 -16 mm) and 16.33  1.53 mm (range: 15 -18 mm), respectively (when the values expressed as mean  standard deviation). The HPLC chromatograms for both OSE and OME displayed 9 major compounds with retention times 1.54 -6.14 min and 1.79 -9.47 min, respectively. Thus, the olive fruit extracts (OME and OSE) possessing various phytochemicals, showed anti-MRSA activity, suggesting the plausible usage of the extracts in the preparation of antibacterial leads in combating various life threatening diseases caused due to S. aureus infection, including MRSA.

Aims: The current study determines the antibacterial activity of 'Bakul' (Mimusops elengi) leaf, seed and bark extracts against gram-negative clinical bacterial isolates as well as the standard bacterial strains. Methods:The disc diffusion method was followed to determine the antibacterial activity of M. elengi leaf, seed and bark extracts against the clinical isolates of Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris and Pseudomonas aeruginosa. The antibiotic susceptibility of the bacterial isolates was determined by disc diffusion. Results:The concentration dependent activity of the extracts against the bacteria was recorded with zone diameter of inhibition 7-21 mm. The extracts in combination with antibiotics (cefpodoxime, gentamycin and ciprofloxacin) had growth inhibitory indices (GIIs), 0.5-0.6, 0.5-0.89 and 0.73-0.82 against E. coli, K. pneumoniae and Pr. vulgaris clinical isolates, respectively, while for the standard strains (E. coli, K. pneumoniae and Ps. aeruginosa) the GIIs ranged 0.56-0.86. Most of the extracts were tested positive for the presence of flavonoids, glycosides, steroids, terpenoids, quinone and phenol. Conclusion:The M. elengi leaf, seed and bark extracts, in combination with antibiotics, had synergistic interactions against all the standard bacterial strains and Pr. vulgaris clinical isolate, while both synergistic and additive interactions were recorded against E. coli and K. pneumoniae clinical isolates.

The antibiotic resistance among gram-positive and gram-negative pathogenic bacteria is of global health concern. This has prompted the development of new effective drugs. But the discovery and development of new drugs is slow, and the emergence of resistance to such new drugs, on the other hand, is rapid as well as continuous among the bacteria. Therefore, in tackling the emergence of antibiotic resistant pathogenic bacteria finding alternative ways is vital. This communication, based on the published scientific data, summarizes the antibacterial capacity of some naturally derived agents such as honey, phytocomponents, probiotics, and antimicrobial peptides that might bring new essence in biomedicine.  Keywords: Bacterial resistance, alternative therapeutics, honey, phytomedicine, probiotics, antimicrobial peptides.

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