Abstract
Background: The olive tree (Olea europaea L.), the most widespread plant species in the Mediterranean basin, includes two forms: cultivated (var Europaea) and wild (var Sylvestris). Wild olive trees or oleasters cover large areas in Algeria. It has been shown that oil from oleaster has a higher content of phenolic compounds, which could have antimicrobial properties.
Objective: The objective of this study was to assess the antibacterial activity of phenolic extracts from four Algerian oleaster oils and an extra virgin olive oil (EVOO) from Chemlal variety.
Methods: Phenolic compounds were determined by UHPLC-MS. Antibacterial activity was tested against six referenced human enteropathogenic bacteria by the agar disc diffusion method by measuring the diameters of the zone of inhibition.
Results: The results revealed a similarity between the phenolic composition of oleasters 1 and 3 and between oleaster 4 and EVOO; however, the phenolic composition of oleaster 2 that the poorer was markedly different with a higher content of free phenolic alcohols and lower in secoiridoids. Almost all bacteria showed to be sensitive against the antibiotics, with the value of ZOI ranging from 5-32 mm; otherwise, most of the oleaster extracts exhibited higher antibacterial activity than the EVOO with ZOI values of 7-12mm. A significant correlation was noted between phenolic content and antibacterial activity.
Conclusion: These results show that oleaster oil can be considered a high potential food.
Keywords: Antibacterial activity, Wild olive, oleaster, phenolic compounds, UHPLC.
Graphical Abstract
[http://dx.doi.org/10.1155/2011/431021] [PMID: 21647315]
[http://dx.doi.org/10.1016/S0040-4020(01)88506-9]
[PMID: 19553175]
[http://dx.doi.org/10.3390/molecules17056083] [PMID: 22614862]
[http://dx.doi.org/10.1021/jf0602267] [PMID: 16819902]
[http://dx.doi.org/10.1111/j.1745-4549.2008.00318.x]
[http://dx.doi.org/10.1108/NFS-01-2016-0010]
[http://dx.doi.org/10.3389/fmicb.2019.01586] [PMID: 31396167]
[http://dx.doi.org/10.1007/s00217-020-03603-y]
[http://dx.doi.org/10.1002/9781119135340.ch7]
[http://dx.doi.org/10.3390/molecules26020273] [PMID: 33430487]
[http://dx.doi.org/10.1155/2021/8869060]
[http://dx.doi.org/10.1016/j.indcrop.2015.12.081]
[http://dx.doi.org/10.1039/C6FO01136E] [PMID: 27713969]
[http://dx.doi.org/10.1016/j.talanta.2007.04.045] [PMID: 19073094]
[http://dx.doi.org/10.1016/j.foodchem.2008.07.057]
[http://dx.doi.org/10.1016/j.foodchem.2011.01.068] [PMID: 25214124]
[http://dx.doi.org/10.1016/j.foodchem.2009.12.013]
[http://dx.doi.org/10.1016/j.foodchem.2004.12.036]
[http://dx.doi.org/10.1016/j.foodchem.2003.07.012]
[http://dx.doi.org/10.1016/j.copbio.2011.09.006] [PMID: 22000808]
[http://dx.doi.org/10.1007/s11745-001-0413-x]
[http://dx.doi.org/10.1021/jf062335r] [PMID: 17253709]
[http://dx.doi.org/10.3390/12081679] [PMID: 17960082]
[http://dx.doi.org/10.1016/j.indcrop.2015.01.077]
[http://dx.doi.org/10.1016/S0308-8146(99)00093-X]
[http://dx.doi.org/10.1016/j.foodcont.2007.05.007]
[http://dx.doi.org/10.1007/s12078-008-9008-2]
[http://dx.doi.org/10.1016/j.scienta.2006.12.036]
[http://dx.doi.org/10.3989/gya.2008.v59.i4.528]
[http://dx.doi.org/10.1016/j.foodres.2011.10.024]
[http://dx.doi.org/10.1016/S0308-8146(00)00276-4]
[http://dx.doi.org/10.4315/0362-028X-70.5.1194] [PMID: 17536679]
[http://dx.doi.org/10.1007/s00396-007-1693-x]
[http://dx.doi.org/10.1016/j.biortech.2009.12.052] [PMID: 20106659]
[http://dx.doi.org/10.3390/microorganisms7090321] [PMID: 31491985]
[PMID: 9670554]
[http://dx.doi.org/10.1016/j.bmc.2006.08.027] [PMID: 16971127]