Comparison of Antibacterial and Antifungal effect of Hydroalcoholicextract of Ephedra Gerardianawith Chlorhexidine 1% on Oral Pathogenesis isolates

Infectious diseases such as tooth decay are a challenge to oral health in humans.Mouthwashes arean auxiliary tool and in addition to this, mechanical dental plaque control i.e. brushing and flossing, play an important role in controlling plaque. In the past three decades, the pharmaceutical industry has produced a significant number of antibiotics, but the resistance of microorganisms to these drugs has increased. Thus, the increasing spread of microbial resistance has made the treatment of infectious diseases difficult and costly. Much research has been done on chlorhexidine-containing solutions, which is a gold standard. Chlorhexidine belongs to the group of medicines called antiseptic antibacterial agentsand its only side effect is a change in tooth color. Therefore, now days it is sought to replace the products with herbal antimicrobial properties due to their availability and low side effects, instead of antibiotics. Ephedraguardianais an herbal medicine that has been used in the treatment of asthma, nasal congestion and disorders of the central nervous system. Almost all species of this plant are adapted to the environmental and climatic conditions of Iran and have significant antimicrobial effects. The aim of this study was to investigate the effect of aqueous and alcoholic extracts of Ephedra gerardiana with chlorhexidine on normal flora of oral bacteria and Candida albicans in vitro.

In this experimental study, the conical section of Ephedra gerardianawascollected and then approved by anexpert of medicinal plants of the Faculty of Agriculture department in Birjand University. Extraction was performed by soaking the conical parts of the plant after drying and grinding.To prepare hydroalcoholicextracts, the plant powder was boiled for one hourand then condensed in a rotary evaporator at a temperature of 60 degrees to reach a volume of 20 ml. The antimicrobial effect of the extracts was determined by broth microdilution method on Enterococcusfaecalis(ATCC29212), Streptococcus mutans (ATCC35668), Lactobacilli casei (ATCC39392) and Candida albicans (ATCC 10231).Thus, the concentrations of chlorhexidine 1%(0.03-10 mg/ml) and hydroalcoholic extractof Ephedra gerardiana(0.01-20 mg/ml)were prepared in 96-well plate wells, respectively.Bacterial cell suspensionwas adjusted to the turbidity of 0.5 McFarland standard and for Candida albicans and 5 × 103 cells mL−1was prepared by spectrophotometry and confirmed byhemocytometric counting.The extract-free wells were considered as positive control and extract control were considered as negative control.  A well microtiter platewas incubated in a 96- for 24 h at37 °C. At the end of this incubation,minimum inhibitory concentration (MIC) andminimum bactericidal concentration (MBC) and minimum fungicidal concentration (MFC) was determined by using colony count on blood agar medium.

The results showed that E. gerardiana aqueous extract did not affect the growth of Enterococcus faecalis and Streptococcus mutans. Enterococcusfaecalis and Streptococcus mutans were resistant to aqueous extractswhile aqueous extract showed an inhibitory effect on Lactobacilli casei and Candida albicans.Lactobacilli casei and Candida albicans had MIC 2.5 and 0.31 mg / ml, MBC/ MFC 0.62 and 5.0 mg / ml, respectively. Enterococcusfaecaliswas also resistant to alcoholic extracts.The results of the alcoholic extract showed that different concentrations of extract did not affect the growth of Enterococcusfaecalis. However, Streptococcus mutans and Lactobacilli casei and Candida albicans were susceptible to alcoholic extracts.Lactobacilli casei, Streptococcus mutans, and Candida albicanshad MICs at 0.07, 1.25, 2.5, mg / ml and MBC/ MFC at0.3, 2.5, 5.0 mg / ml, respectively. Also,chlorhexidine 1% showed an inhibitory effect on all bacterial strains and Candida albicans. All three bacterial strains (Enterococcusfaecalis, Streptococcus mutans and Lactobacillus casei) had MIC at 1.25 and0.07 mg / ml and MBC 2.5 and0.3 mg / ml to chlorhexidine 1%respectively. Furthermore, Candida albicans demonstrated MIC at 0.3 mg / ml and MFC at 0.62 mg / ml to chlorhexidine.

The results of the effect of hydroalcoholic extractof Ephedra gerardianashowed that it has antibacterial effects on some gram-positive bacteria of normal oral flora, including Streptococcus mutans,Lactobacillus casei and Candida albicans. Compared to the effect of different concentrations of chlorhexidine 1% and hydroalcoholic extractitdid not have a significant effect on the growth of Enterococcus faecalis. According to the study, with the exception ofEnterococcus faecalis, which was resistant to all aqueous and alcoholic extracts, Ephedra gerardiana extract has antibacterial and antifungal properties and therefore can be an effective antimicrobial agent compared with chlorhexidine 1% as a commercial mouthwash solution that has side effects of tooth discoloration;Ephedra gerardianaextract can be used alone or in combination with other antimicrobial agents as mouthwashes.To better identify the performance and antimicrobial properties of Ephedra, it is recommended that different species of Ephedra be collected from different areas and examined phytochemically.