Antibacterial Activity of a Fractionated Pistacia lentiscus Oil Against Pharyngeal and Ear Pathogens, Alone or in Combination With Antibiotics

Abstract

Previous studies have clearly demonstrated that the addition of lentisk oil (LO) to streptococcal cultures makes it possible to differentiate Streptococcus spp. into three categories with Streptococcus mitis and Streptococcus intermedius sensitive, Streptococcus pyogenes, Streptococcus agalactiae, and Streptococcus mutans partially sensitive, and Streptococcus salivarius insensitive to the product. We have investigated here whether the winterization of LO, an easy and cheap procedure that removes some of the fatty substances contained within, resulted in a better antimicrobial effect on human pathogens affecting the pharyngeal mucosa and middle ear such as S. pyogenes, S. pneumoniae, Moraxella catarrhalis, and Haemophilus influenzae, without affecting, or minimally affecting, S. salivarius strains, oral probiotics commonly used to reduce oral and middle ear infection recurrence, especially in children. Our results not only demonstrated a stronger antimicrobial action of winterized LO (WLO) on S. pyogenes, compared to what was seen with LO, but also demonstrated a strong antimicrobial action vs. S. pneumoniae and M. catarrhalis and a very limited effect on S. salivarius (strains K12 and M18). Moreover, WLO demonstrated a co-acting action when tested along with the antibiotics amoxicillin (A) and amoxicillin clavulanate (AC), effects clearly visible also on H. influenzae. Our results also showed that at least part of the antimicrobial effect observed was due to the presence of anacardic acids (AAs). Finally, WLO, when tested with human peripheral blood mononuclear cells (h-PBMCs), reduced the release of IL-6 and TNF-α and, in the case of cells stimulated by LPS, the release of IFN-γ. In conclusion, our study highlights an enhanced antimicrobial role for LO when winterized, suggests a co-acting effect of this when given with antibiotics, identifies AAs as possible active ingredients, and proposes a possible anti-inflammatory role for it.

Overview of Chios Mastic Gum (Pistacia lentiscus) Effects on Human Health

“…In fact, the inhibitory effect was proportionate to the concentration of the added oil [46]. More recent studies have demonstrated a strong antimicrobial action of mastic against Streptococcus species and several other common pharyngeal and ear pathogens, either when administered alone or in combination with antibiotics [47]. Moreover, the effective inhibition of numerous periodontal pathogens, without exhibiting any cytotoxic effects towards cells of epithelial or mesenchymal origin, makes mastic gum an ideal antimicrobial factor for oral inflammatory diseases [48].…”

Antimicrobial Activities of Pistacia lentiscus Essential Oils Nanoencapsulated into Hydroxypropyl-beta-cyclodextrins

“…lentiscus resins, particularly against Helicobacter pylori, a main cause of gastric ulcers and gastric cancers, in. − Since 1995, additional antimicrobial activities exerted by P. lentiscus extracts have been reported against different Gram+ve and Gram-ve bacteria, including Salmonella enteritidis, Pseudomonas fragi, Lactobacillus plantarum, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and different Streptococcus species. − …”

Xanthine Oxidase Inhibitory Activity and Chemical Composition of Pistacia chinensis Leaf Essential Oil

“…Antimicrobial, including antibacterial and antifungal, activities were found in the essential oils or extracts from P. lentiscus leaf, berry and bark, P. atlantica mastic gum, and P. atlantica leaf and fruit [ 20 , 21 , 23 , 28 , 29 , 30 ]. Antioxidant activity has been reported in P. atlantica subsp.…”