Synergistic interaction and mode of action ofCitrus hystrixessential oil against bacteria causing periodontal diseases

Abstract

Context: Citrus hystrix de Candolle (Rutaceae), an edible plant regularly used as a food ingredient, possesses antibacterial activity, but there is no current data on the activity against bacteria causing periodontal diseases. Objective: C. hystrix essential oil from leaves and peel were investigated for antibiofilm formation and mode of action against bacteria causing periodontal diseases. Materials and methods: In vitro antibacterial and antibiofilm formation activities were determined by broth microdilution and time kill assay. Mode of action of essential oil was observed by SEM and the active component was identified by bioautography and GC/MS. Results and discussion: C. hystrix leaves oil exhibited antibacterial activity at the MICs of 1.06 mg/mL for P. gingivalis and S. mutans and 2.12 mg/mL for S. sanguinis. Leaf oil at 4.25 mg/ mL showed antibiofilm formation activity with 99% inhibition. The lethal effects on P. gingivalis were observed within 2 and 4 h after treated with 4 Â MIC and 2 Â MIC, respectively. S. sanguinis and S. mutans were completely killed within 4 and 8 h after exposed to 4 Â MIC and 2 Â MIC of oil. MICs of tested strains showed 4 times reduction suggesting synergistic interaction of oil and chlorhexidine. Bacterial outer membrane was disrupted after treatment with leaves oil. Additionally, citronellal was identified as the major active compound of C. hystrix oil. Conclusions: C. hystrix leaf oil could be used as a natural active compound or in combination with chlorhexidine in mouthwash preparations to prevent the growth of bacteria associated with periodontal diseases and biofilm formation.

Bioactivity of Citrus essential oils (CEOs) against microorganisms associated with spoilage of some fruits

“…The better antimicrobial efficacy may be as a result of the mixture of chemically different biologically active compounds such as terpenes, both oxygenated and non-oxygenated [59]. Dinan et al [60] revealed that the mode of action of EOs takes place against microorganisms by attacking the microbial cell wall, which resulted in increased permeability and loss of cellular constituents, acidification of the cytoplasmic content; blocking the production of cellular energy and synthesis of structural components; and, finally, destruction of genetic material leading to the death of the microorganisms [61]. The synergistic activity of CEOs may be due to their actions on microbial cell membrane.…”

Larvicidal Activity of Essential Oil of Syzygium aromaticum (Clove) in Com-parison with Its Major Constituent, Eugenol, against Anopheles stephensi

“…LC 50 of EO of Allium macrostemon (72.86 ppm) was better than a major constituent, methyl propyl disulfide (86.16ppm), while its efficacy was lower than the other major component, dimethyl trisulfide (36.36ppm), against Ae. albopictus (40).…”

“…Synergistic effects of constituents of some EOs are nowadays well-known when they are used as anti-fungal or anti-bacterial agents (39, 40). Our findings in this research and our previous study also show that An.…”

Synergistic effects of natural products and commercial antibiotics—A mini–review 2010–2015

“…Cont. Table 1: Summary of plants screened for antibiotic modulatory effects of commercially available drugs against nosocomial bacteria, that yielded synergistic effects 32,45,[80][81][82][83][84][85] . is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.…”