Antimicrobial Activity of Essential Oils of Lamiaceae Aromatic Spices Towards Sheep mastitis-Causing Staphylococcus aureus and Staphylococcus epidermidis

Abstract

Mastitis in ewes is responsible for massive economic losses. Antibiotics are routinely used for mastitis control but its excessive use leads to development of antibiotic resistance with deleterious outcomes both for animal and public health. Essential oils (EOs) show antibacterial proprieties and no resistance has been reported after prolonged exposure; however their efficacy depends on their chemical composition. In this study EOs chemical composition from four autochthonous aromatic herbs, from Alentejo region, southern Portugal, Calamintha nepeta subsp. nepeta, Lavandula stoechas subsp. luisieri, Rosmarinus officinalis and Thymus mastichina was accessed. EOs of R. officinalis showed predominance in monoterpene hydrocarbons (63 %) whereas EOs of T. mastichina, L. luisieri and C. nepeta were rich in oxygenated monoterpenes (71-95 %). The antimicrobial activity of selected EOs was investigated towards Staphylococcus aureus (n= 24) and Staphylococcus epidermidis isolates (n= 24) from ovine mastitic milk origin. Results of disk diffusion assay revealed that C. nepeta, L. luisieri and T. mastichina EOs are highly active against both S. aureus and S. epidermidis strains, whereas R. officinalis EO is highly active against S. aureus strains but inactive against several S. epidermidis isolates. EOs concentration causing bacterial growth inhibition ranged from 500 to 4,000 μg mL-1 in liquid microassays.

New Tricks for Old Guys: Recent Developments in the Chemistry, Biochemistry, Applications and Exploitation of Selected Species from the Lamiaceae Family

“…luisieri, Rosmarinus officinalis and Thymus mastichina EOs among others was investigated towards Staphylococcus aureus and Staphylococcus epidermidis isolates from ovine mastitic milk origin. [277] Results of disk diffusion assay revealed that L. luisieri and T. mastichina EOs are highly active against both S. aureus and S. epidermidis strains, whereas R. officinalis EO is highly active against S. aureus strains but inactive against several S. epidermidis isolates. Finally the effects of intramammary infusion of sage (Salvia officinalis) essential oil on milk somatic cell count, milk composition parameters and selected hematology and serum biochemical parameters in 20 ewes affected with subclinical mastitis were studied by Alekish et al [278] In this study, the intramammary infusion of sage EO to ewes affected with subclinical mastitis resulted in a significant decrease in milk somatic cells count 24 h and 48 h post treatment.…”

“…The antimicrobial activity of Lavandula stoechas subsp. luisieri , Rosmarinus officinalis and Thymus mastichina EOs among others was investigated towards Staphylococcus aureus and Staphylococcus epidermidis isolates from ovine mastitic milk origin . Results of disk diffusion assay revealed that L. luisieri and T. mastichina EOs are highly active against both S. aureus and S. epidermidis strains, whereas R. officinalis EO is highly active against S. aureus strains but inactive against several S. epidermidis isolates.…”

Thymus mastichina: Composition and Biological Properties with a Focus on Antimicrobial Activity

“…The effect of T. mastichina essential oil was evaluated on several bacteria of the Enterobacteriaceae family ( E. coli, Salmonella spp.) with an origin in poultry and pigs species, was registered with MIC values with 4% ( v / v ) [ 29 ], as well as in other studies against methicillin-sensitive S. aureus and S. epidermidis isolates from ovine mastitic milk [ 48 ].…”

“…As shown in Figure 2 and Table 1 , the composition of the essential oil of T. mastichina is quite diverse, being constituted by hydrocarbon and oxygenated monoterpenes and sesquiterpenes, presenting main constituents of 1,8-cineole (also known as eucalyptol) and linalool. The major constituents of the essential oil of T. mastichina have been determined by gas chromatography [ 2 , 4 , 8 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 47 , 48 ]. Table 1 summarizes the major constituents present and it can be seen that their composition varies according to origin.…”

Environmental Bovine Mastitis Pathogens: Prevalence, Antimicrobial Susceptibility, and Sensitivity to Thymus vulgaris L., Thymus serpyllum L., and Origanum vulgare L. Essential Oils

“…However, antibiotic resistance in bacteria is an increasing threat, and there is a need for new, alternative therapies, including essential oils (EOs) [ 18 ]. Along with other advantages as an alternative to antibiotics, EOs show antibacterial properties and no resistance has been reported after prolonged exposure [ 19 ]. There are many in vitro studies for evaluating the antimicrobial efficacy of EOs against common mastitis-associated pathogens [ 20 , 21 , 22 , 23 , 24 ].…”