The Antibacterial Effect of Mentha Piperita L. Against Streptococcus Mutans as Mouthwash

Right through history, from the genus Mentha L. and the family (Lamiaceae), species which includes about 260 genera and more than 7000 species are being used worldwide and one example is Mentha piperita L. (Brahmi, Khodir, Mohamed & Pierre, 2017) commonly known as peppermint a hybrid of spearmint (Mentha spicata L.) and watermint (Mentha aquatica L.) has strong sweetish aroma and a warm pungent taste with a cooling aftertaste (Encyclopaedia Britannica, 2018). It is a perennial herb 50–90 cm in height, typically quadrilateral, commonly branched stems are generally tainted violet but occasionally grey-haired and dark or light green leaves are short-petiole, oblong-ovate and serrate with margins finely toothed while the flowers are purple or pinkish having false spikes with numerous unnoticeable bracts and seldom bear seeds or most often sterile and spreads by means of runners and grows in a sunny side and prefers acid, neutral and basic, light, medium soils but can also grow in heavy clay soil (Belkheir, Shushni, & Singh, 2015). It was grown all over Asia, Europe, and North America ever since it was introduced to London Pharmacopoeia in 1721 due to its essential oil (Brahmi, Khodir, Mohamed, & Pierre, 2017) extracted from the aerial parts of the flowering plant, the dried leaves, the fresh flowering plant and the whole plant that’s been used as medicine (Belkheir, Shushni, & Singh, 2015), while dried flowers are used as flavorant and fresh leaves normally used as culinary herb, (Encyclopaedia Britannica, 2018) as therapy for common cold, inflamed mouth, pharynx, liver, also disorders in gastrointestinal tract like nausea, vomiting, diarrhoea, cramps, flatulence and dyspepsia. M. piperita L. has long been used as safe medicinal preparations, less toxic than the synthetic ones, contains wide variety of bio-active compounds which is a great source in phytochemicals, anti-oxidant, antinociceptive, anti-inflammatory, antimicrobial, anti-carcinogenic, antiviral, anti-allergic and antitumorigenic beneficial in the prevention or treatment of several diseases. In addition M. piperita L has a great potential for economical and inexpensive application both in medical and food industry (Barbalho, Guiguer, Menezes, & Trevisan, 2017).

Mentha piperita L. yields 0.1–1% of volatile oil composed primarily of menthol (29–48%), menthone (20–31%), menthofuran (6.8%) and menthyl acetate (3–10%). Other pharmacologically active ingredients include bitter substances, caffeic acid, flavonoids (12%), polymerized polyphenols (19%), carotenes, tocopherols, betaine, choline and tannins (Singh, Shushni, & Belkheir, 2015). Levo-menthol, a levorotatory form obtained naturally from Menthol also known as peppermint camphor, terpene alcohol with a strong minty, cooling odour and taste is obtained from peppermint oil or is produced synthetically by hydrogenation of thymol. It is medicinally used in ointments, cough drops, nasal inhalers and is also used as flavouring in foods, cigarettes, liqueurs, cosmetics, and perfumes (Wade, 2018). Due to its pleasurable mint flavour and cooling sensation on mouth, lungs and throat, cigarettes with menthol “one cause of tooth decay (Dental Health & Your Health, 2016)” gained popularity in the 1950’s and usually sold as "healthy" cigarettes (Wickham, 2015), but is now being pointed out by studies as the primary initiator in increasing numbers of youth (people aged 11-17) and young adult (people aged 18-30 years) smokers. Although little proof shows menthol in cigarettes as cause of nicotine dependence and unsuccessfully stops smoking, studies indicate that menthol’s cooling and anaesthetic properties gentles and softens cigarette's taste pose a public health risk. As a sort of countermeasure to this alarming state of youth and young adult smokers, WHO created the Study Group Tobacco Product Regulation (TobReg) which presents its first advisory note on menthol in tobacco products that undoubtedly recommends banning the use of menthol and its analogues, precursors or derivatives in cigarettes and possibly all tobacco products (World Health Organization, 2016). This may be a great opportunity for the members of mint family to advance further and reclaim its prime as traditionally used herb and medicine in order to bridge the gap from the time it was abused and wrongly used.

Having your teeth completely disappear can sometimes loss your smile and cause to degrade self-esteem, self-worth resulting to social withdrawal and hard to eat your favourite, suitable nutritional food therapy (Kalman, 2017). Tooth decay, one cause of imperfect smile is the loss of the outer layer of tooth the enamel and the calcified tissue surrounding the pulp cavity of tooth the dentin that happens when food having carbohydrates are neglected on teeth and the bacteria that is present on mouth digests and convert those foods into acids. Bacteria, acid, food remains, and saliva mix to form plaque that attaches the teeth to breakdown enamel surface resulting to cavities on teeth (Friedman, 2017). Cavities are usual for children, but due to old age it becomes a problem for adults too. Break down on the edges or margin of fillings is also usual for older adults due to not enough fluoride and modern prophylactic dental care when growing up (American Dental Association, 2018). A survey shows that 45% of 10,000 adults failed to brush their teeth at night due to tiredness, forgetfulness and laziness while 28% just use water to brush and 14% use only finger to brush (Parry, 2015). So, we the student pharmacists of University of Negros Occidental - Recoletos wants to formulate a mouthwash using the extracts of Mentha piperita L. leaf that perhaps could ease, save time and effort to the lives of people and help minimize some causes of cavity most especially bacterial cause, since mouthwash aids to minimize and sustain few levels of bacteria, wash out food debris, and halts bad breath in mouth due to its fresh minty aroma (Parry, 2015).

Charles Darwin, in his theory of natural selection, described the “survival of the fittest” as the change of living organisms by time called evolution. Evolution, a biological phenomenon given to all living organisms resulting to the formation of new life-forms supported by fossil records, structure, function, embryological development, DNA and RNA studies (Green, Joshi, & Rogers, 2018). In order to survive, organisms have formed toxic compounds as protection to combat and make advancements for existence, and also created resistance for their toxins produced. Bacteria create proteins infectious to host, such as diphtheria toxin, bacteriocins which is toxic to bacteria. Toxins indirectly lead modification through cell death that change cell division to boost transformation (Fridovich, Keil, & Robinson, 2018). So in relating this theory to our study, we will mainly focus on the inhibition of the growth of Streptococcus mutans a disease carrying organism found in mouth (Bhardwaj, Bhondey, Chandak, Chandwani & Pimpale, 2016), a bacterial specie from the genomes of microbes attaches on tooth which breaks down sugars to form acid resulting to cavity that creates biofilms “a mucus like formation of bacteria (Bhutia, et al., 2018)” which have amyloid fibrils an insoluble filament protein formation used by bacteria to enhance activeness of its biofilms (Paranjapye, & Daggett, 2018).

This study aims to promote that Peppermint (Mentha piperita L.) isn’t just used as flavorant and additive in cigarettes, candies, culinary herbs, cosmetics and pharmaceuticals but can also be used as a primary constituent in the development of new pharmaceutical product containing an active constituent of Levo-menthol obtained naturally from peppermint oil proven to have an anti-antibacterial properties and will be introduced in the market as mouthwash to inhibit the growth of Streptococcus mutans.