Review Article Plant Extracts with Activity against Oral Bacteria Jacob Mathew Philip1*, K. Mahalakshmi2, L. Jeyanthi Rebecca3, C. J. Venkatakrishnan4, Chitra R. Chandran5 ABSTRACT The association between oral diseases and oral microbiota is well established. The development of dental caries involves Gram-positive bacteria (mutans streptococci, lactobacilli, and actinomycetes). Periodontal diseases have been linked to anaerobic Gram-negative bacteria (Porphyromonas gingivalis, Actinobacillus, Prevotella, and Fusobacterium). Given the incidence of oral disease, increased resistance by bacteria to antibiotics, adverse affects of some antibacterial agents currently used in dentistry there is a need for alternative prevention and treatment options that are safe, effective, and economical. While several agents are commercially available, these chemicals can alter oral microbiota and have undesirable side-effects. In this review, plant extracts or phytochemicals that inhibit the growth of oral pathogens, reduce the development of biofilms and dental plaque, influence the adhesion of bacteria to surfaces, and reduce the symptoms of oral diseases will be discussed. KEY WORDS: Antibacterial, Oral bacteria, Oral disease, Plant extracts INTRODUCTION oral bacteria. These studies have focused on bacteria known to be involved in the etiology of orodental There have been numerous reports of the use of diseases. Many studies have clearly established that traditional plants and natural products for the treatment a number of substances had potential to be utilized of oral diseases. Many plant-derived medicines used in the dental industry, given their activity against in traditional medicinal systems have been recorded cariogenic bacteria, and those bacteria associated with in pharmacopeias as agents used to treat infections periodontal diseases. Substances that exhibited activity and a number of these have been recently investigated included extracts such as cinnamon bark oil, papua- for their effect against oral microbial pathogens. The mace extracts, and clove bud oil and constituents of antimicrobial properties of medicinal plants and plant these extracts.[1] products are reviewed here. Traditional medicinal plant extracts that have been shown to inhibit the Many studies investigating the activity of traditional growth of oral pathogens, reduce the development of medicinal plants against oral pathogens have been dental plaque, influence the adhesion of bacteria to done for examination of crude aqueous or organic surfaces, and reduce the symptoms of oral diseases solvent extracts. In most cases, the investigators will be discussed. have sought to validate the traditional medicinal use of the plant. For example, the use of Drosera peltata PLANT EXTRACTS WITH (Droseraceae) leaves as a traditional treatment for dental caries was validated by a study which showed ACTIVITY AGAINST ORAL that chloroform extracts of the aerial plant parts BACTERIA showed broad-spectrum activity against numerous bacteria of the oral cavity, with greatest activity against There have been numerous studies that have Streptococcus mutans and Streptococcus sobrinus.[2] investigated the activity of plant substances against Plumbagin was identified as the active component of this extract. Access this article online Tichy and Novak[3] investigated a collection of Website: jprsolutions.info ISSN: 0975-7619 27 medicinal and random plants extracts and identified 1Research Scholar, Sree Balaji Dental College, BIHER, Bharath University, Velachery Main Rd, VGP Rajesh Nagar, Pallikaranai, Chennai, Tamil Nadu 600100.2Dept. of Microbiology, Sree Balaji Dental College, BIHER, Bharath University, Velachery Main Rd, VGP Rajesh Nagar, Pallikaranai, Chennai, Tamil Nadu 600100. 3Dept. of Biotechnology, BIHER, Bharath University, 173, New Agaram Rad, Selaiyur, Chennai, Tamil Nadu 600073,India. 4Dept of Prosthodontics, Tagore Dental College, Near Vandalur, Melakkottaiyur Post, Rathinamangalam, Tamil Nadu 600127, India. 5Dept. of Periodontics, Tagore Dental College, Near Vandalur, Melakkottaiyur Post, Rathinamangalam, Tamil Nadu 600127, India *Corresponding author: Dr. Jacob Mathew Philip, BIHER, Bharath University, 173, New Agaram Road, Selaiyur, Chennai - 600 073, Tamil Nadu, India. Received on: 16-02-2018; Revised on: 16-03-2018; Accepted on: 19-05-2018 1088 Drug Invention Today | Vol 10 • Issue 7 • 2018 Jacob Mathew Philip, et al. a number that inhibited the growth of oral streptococci. Harungana madagascariensis (Hypericaceae) is a The most active extracts included those from Abies native African plant with antimicrobial properties Canadensis (Pinaceae), Albizia julibrissin (Fabaceae), that contains numerous antimicrobial components. Chelidonium majus (Papaveraceae), Ginkgo biloba Using successive Soxhlet solvent extractions, an (Ginkgoaceae), Juniperus virginiana (Cupressaceae), ethyl acetate extract of leaves was prepared and tested Pinus virginiana (Pinaceae), Rosmarinus officinalis against numerous oral pathogens. While the extract (Lamiaceae), Sassafras albidum (Lauraceae), was able to kill all oral bacteria tested (including Tanacetum vulgare (Asteraceae), and Thuja plicata Actinomyces, Fusobacterium, Lactobacillus, (Cupressaceae). Bioautography indicated that a Prevotella, Propionibacterium, and Streptococcus number of extracts contained common antimicrobial species), poly (d,l-lactide-co-glycolide) nanoparticles components, while other extracts possessed chemically containing extract showed enhanced activity. The different constituents. authors suggested that this may have been due to the bioadhesive properties of the polymer resulting in the Garlic, Allium sativum (Liliaceae), has been used extract being in contact with the bacteria for prolonged as a medicine since ancient times because of its periods.[9] antimicrobial properties. While garlic has been shown to have activity against a wide range of bacteria, Smullen et al.[10] determined the ability of commercially the specific activity against the Gram-negative oral available extracts or fresh aqueous propanone extracts pathogens including P. gingivalis has only recently (PE) of foods with high polyphenol content to inhibit been demonstrated.[4] A garlic extract containing the the growth of S. mutans and other oral pathogens. major antimicrobial component, allicin, was active All the extracts showed activity, with the PE of red toward Gram-negative pathogens less active against grape seeds exhibiting the greatest activity against S. Gram-positive bacteria. The extract almost completely mutans. The green tea and unfermented cocoa PE were inhibited trypsin-like protease activity (implicated most active against other oral pathogens. Overall, the in the pathogenesis of periodontitis) of P. gingivalis. commercial extracts were not as active as the PE. Taken together, these observations suggest that garlic Various PEs were also able to prevent adhesion of S. extract or allicin may be of therapeutic use against mutans to glass. These data suggest that extracts of periodontal diseases or other oral diseases. polyphenol-containing foods may have a preventative role against dental caries. A boiling water extract of Coptidis rhizoma (Ranunculaceae), a traditional Chinese medicinal Helichrysum italicum (Compositae) is widely found plant, showed bactericidal activity against oral in the Mediterranean region and has been shown to bacteria with particularly good activity against have a variety of biological properties. An ethanol periodontopathogenic bacteria.[5] Iauk et al.[6] extract of powdered flowering tops was found to exert assessed the ability of 10% decoctions and methanol antimicrobial activity against S. mutans, Streptococcus [11] extracts of a number of medicinal plants to inhibit Sanguis, and S. sobrinus. bacterial isolates obtained from crevicular fluid of Two recent studies have examined a number of plants the periodontal pockets of periodontic patients. In traditionally used in Brazil[12] and South Africa,[13] general, the methanol extracts showed greater activity respectively, for activity against oral pathogens. Plant than the decoctions. The extract from the leaves of extracts of Cocos nucifera (Palmae), Ziziphus joazeiro Hamamelis virginiana (Hamamelidaceae) had the (Rhamnaceae), Caesalpinia pyramidalis (Fabaceae), greatest overall activity against all bacteria tested, and Aristolochia cymbifera (Aristolochiaceae) were particularly against Porphyromonas spp., Preveotella active against the test bacteria, with the ethanol extract spp., and Actinomyces Odontolyticus. of A.cymbifera being the most effective. The resin exuded by the Pistacia lentiscus Crude ethanol extracts of Piper cubeba (Piperaceae) (Anacardiaceae) tree, known as mastic gum, is used exhibited good antimicrobial properties against a range in the preparation of foods and as a remedy for oral of cariogenic pathogens, although no information malodor and has been shown to have antimicrobial about the activity against periodontal pathogens was activity. The activity of a mastic gum extract against provided.[14] P. gingivalis was demonstrated using disc diffusion assays, but its low solubility suggested that it Cold and hot water and ethanolic extracts of Breynia may be useful for local application rather than as a nivosa (Euphorbiaceae) and Ageratum conyzoides mouthrinse.[7] The antibacterial activity of Pistacia (Asteraceae) were tested for activity against vera extracts against oral streptococci has also been S. mutans.[15] While the hot water and ethanol