Antimicrobial and Antioxidant Activities of Polyphenols against Streptococcus mutans

Abstract

Natural polyphenols, gallic acid, tannic acid, quercetin and salicylic acid, were investigated for their antimicrobial and antioxidant activities against Streptococcus mutans. Ascorbic acid, well known for its antimicrobial and antioxidant activities, was used as a criterion for the polyphenols. The antimicrobial effect was assessed using the plate dilution assay and the minimum inhibitory concentration (MIC) of each polyphenol was then determined from the antimicrobial activity results. Salicylic acid was the weakest antimicrobial with the highest MIC (3.8 mg/mL), and tannic acid was the strongest antimicrobial with the lowest MIC of 0.4 mg/mL. Antioxidant capacities were evaluated using the DMPD and ABTS decolorizing assays. These polyphenols show high antimicrobial activity and inoxidizability. Antioxidant activity for quercetin according to the DMPD method was inconclusive because it had color interference with the DMPD radicals. Although some conflicting results were observed between the DMPD and ABTS methods, the polyphenols with high antioxidant capacities still showed high antimicrobial activities, which suggest that the antioxidant capacity attributes to the antimicrobial effects.

Supercritical Fluid Extraction of Polyphenols from Vietnamese Callisia fragrans Leaves and Antioxidant Activity of the Extract

“…However, as the ethanol concentration continued to rise above 14%, antioxidant activity fell down rapidly. is could be articulated by the strong relationship between ethanol concentration and free radical properties of the crude extract due to the hydroxyl groups of polyphenols [23]. In accordance with other studies, it is revealed that the antioxidant activity of polyphenols has been strongly relevant to its structures [4].…”

Antimicrobial and antioxidant activity of the vegetative and reproductive organs of Robinia pseudoacacia

“…(8)(9)(10)(11)(12)(13)(14) mm for all extracts) and lower than 6 mm for the solvent control. In addition, the 70 % ethanol solvent control showed some activity against K. pneumoniae strains, A. baumannii and Candida sp.…”

“…14 Microbial cells are negatively affected by derived substances from plants via various mechanisms of action that attack the phospholipid bilayer of the cell membrane and disrupt enzyme systems. 16 According to the literature, 17,18 a number of polyphenols (catechin, epicatechin, rutin and quercetin) that have been identified in some vegetal extracts show antimicrobial activity.…”

A randomized controlled trial evaluating antioxidant–essential oil gel as a treatment for gingivitis in orthodontic patients

“…The lack of larger group differences in plaque reduction may have been due to the plaque retentive nature of orthodontic appliances. 6,27 While antioxidants have been shown to have an effect on plaque bacteria in vitro, 16,17 and essential oil mouth rinse has been shown to reduce plaque in vivo, 15,28 these effects may be limited during orthodontic treatment. 29 This is consistent with the findings of Tufekci et al 25 and Chen et al, 30 who showed small, and statistically insignificant, increases in PI over 6 months in orthodontic patients using essential oil mouth rinses.…”

“…15 There is also a developing body of evidence to suggest that antioxidants are useful in the treatment of gingivitis. [16][17][18] The clinical trials evaluating the use of antioxidants for the treatment of gingivitis have found decreased severity of gingivitis, decreased bleeding on probing, and modest reduction in pocket depth. 19,20 However, none of the trials included orthodontic patients or used ferulic acid or phloretin in the treatment of gingivitis.…”