The inhibitory effect of a novel neem paste against cariogenic bacteria

Abstract

Background Dental caries is a major oral health problem, which associates with cariogenic bacteria. Streptococcus mutans and Lactobacillus acidophilus are facultative anaerobic bacteria that are found in tooth decay. Accordingly, neem leaf extract was developed due to its great anti-microbial property against many bacteria. The aim of this study was to determine anti-cariogenic properties of neem leaf extract in a novel paste preparation. Material and Methods The neem extract was derived from maceration of dry neem leaves in ethanol for 48 h. The ethanolic extract was subjected to chemical identification using GC-MS. Neem pastes were prepared from ethanolic extract mixed with polyethylene glycol paste with or without zinc oxide. S. mutans and L. acidophilus test were initiated at bacterial concentration of 108 CFU/ml. The antibacterial activity was then performed by disc diffusion method following by minimum bactericidal concentration (MBC) technique. Results GC-MS result displayed 35 compounds. Compounds found in the extract were n-Hexadecanoic acid (31.18%), Hentriacontane (18%), Phytol (16.79%). Disc diffusion showed that ethanolic extract and neem pastes inhibited growth of both bacteria. For MBC, neem paste with zinc oxide at concentration of neem 0.4 mg/ml was the most effective concentration on inhibiting S. mutans growth. Neem pastes and ethanolic extract at concentration of neem 6.25 mg/ml inhibited L. acidophilus growth. Conclusions The ethanolic neem leaf extract and novel neem pastes had antimicrobial effect on both S. mutans and L. acidophilus . By this property, neem paste could be developed for the application in dental field, i.e. pulp capping. Key words: Neem, Azadirachta indica, antimicrobial, cariogenic bacteria.

Dose-dependent effects of neem crude extract on human dental pulp cell and murine osteoblast viability and mineralization

“…Nine out of thirty-five compounds were phytol, α-capaene, α-humulene, β-caryophyllene, δ-cadinene, carvone, aromadendrene, octadeamethyl-cyclononasiloxane, and β-bourbonene. According to previous studies, these compounds possessed the anti-proliferative property 13 - 21 (see detail in Discussion). One compound, β-caryophyllene, possessed mineralization induction property 22 .…”

“…GC-MS allowed the detection of various substance groups including sesquiterpenoids, diterpenes, terpenoid, organoheterosilanes, trialkylamines, ethylamines, fatty acid, amino acid, carboxylic acids, hydrocarbon, benzofuran, barbiturate, glucoside and furanoid. From the ethanolic neem extract, 35 compounds were identified 13 . Nine out of thirty-five compounds were phytol, α-capaene, α-humulene, β-caryophyllene, δ-cadinene, carvone, aromadendrene, octadeamethyl-cyclononasiloxane, and β-bourbonene.…”

“…The mixture was incubated in shaker incubator for 24 h, boiled in hot water bath for 30 min and incubated in shaker incubator for 24 h. The resulting solvent was filtered through Whatman No.1 filter paper and evaporated by rotary evaporator under reduced pressure at 40°C to obtain the crude extract. Then, the crude extract was subjected to phytochemical identification by gas chromatography-mass spectrometry (GC-MS) as previously described 13 . Identification of compounds was achieved by comparing them with the MS known library.…”

Neem leaf powder (Azadirachta indica) mitigates oxidative stress and pathological alterations triggered by lead toxicity in Nile tilapia (Oreochromis niloticus)

“…Heterocyclic compounds, including polysaccharides and carbohydrates, have many active centers and electronegative atoms. All active groups, electronegative atoms, polysaccharide compounds, carbohydrates, and oxygen atoms, in the case of the ionic state, have partial ionization that can adsorb the ionized lead element in solution, and this adsorption is a chemical as well as physical adsorption 90 . The coordination tendency of aromatic electrons to donate groups involving hydroxyl, ether, and phenyl groups is much superior to that in corresponding aliphatic groups.…”

The Antimicrobial Potential of the Neem Tree Azadirachta indica

“…Additional biologically relevant studies may be able to provide even more evidence for the use of neem in dentistry in combination with, or as an alternative to, antimicrobials already used in the field. Of note, several studies have already suggested that neem extracts have similar levels of activity as chlorhexidine or hypochlorite (typical components of oral washes) against plaque, gingivitis, and pain in vivo ( Jalaluddin et al, 2017 ; Hosny et al, 2021 ) and against biofilm-forming bacteria (e.g., Streptococcus viridans, Porphyromonas gingivalis, and S. aureus ) and C. albicans in vitro or ex vivo ( Joy Sinha et al, 2015 ; Anand et al, 2016 ; Kankariya et al, 2016 ; Heyman et al, 2017 ; Andonissamy et al, 2019 ; Bansal et al, 2019 ; Tasanarong et al, 2021 ). Another human pathogen that causes plaque and other biofilm-related diseases in the body, E. faecalis , is also just as susceptible to various neem extracts as it is to chlorhexidine in vitro ( Chandrappa et al, 2015 ; Mustafa, 2016 ; Bhardwaj et al, 2017 ; Joy Sinha et al, 2017 ).…”