Benzyl Isothiocyanate, a Major Component from the Roots of Salvadora Persica Is Highly Active against Gram-Negative Bacteria

Plants produce a number of antimicrobial substances and the roots of the shrub Salvadora persica have been demonstrated to possess antimicrobial activity. Sticks from the roots of S. persica, Miswak sticks, have been used for centuries as a traditional method of cleaning teeth. Diverging reports on the chemical nature and antimicrobial repertoire of the chewing sticks from S. persica led us to explore its antibacterial properties against a panel of pathogenic or commensal bacteria and to identify the antibacterial component/s by methodical chemical characterization. S. persica root essential oil was prepared by steam distillation and solid-phase microextraction was used to sample volatiles released from fresh root. The active compound was identified by gas chromatography-mass spectrometry and antibacterial assays. The antibacterial compound was isolated using medium-pressure liquid chromatography. Transmission electron microscopy was used to visualize the effect on bacterial cells. The main antibacterial component of both S. persica root extracts and volatiles was benzyl isothiocyanate. Root extracts as well as commercial synthetic benzyl isothiocyanate exhibited rapid and strong bactericidal effect against oral pathogens involved in periodontal disease as well as against other Gram-negative bacteria, while Gram-positive bacteria mainly displayed growth inhibition or remained unaffected. The short exposure needed to obtain bactericidal effect implies that the chewing sticks and the essential oil may have a specific role in treatment of periodontal disease in reducing Gram-negative periodontal pathogens. Our results indicate the need for further investigation into the mechanism of the specific killing of Gram-negative bacteria by S. persica root stick extracts and its active component benzyl isothiocyanate

Effect of Salvadora Persica L Root on pH and Buffering Capacity of Saliva

The pH of saliva can be influenced by several factors such as diet, medication, disease, physiological conditions and age. The local effect of food and other substances on the buffering capacity of saliva has been the subject of many studies. It was shown that saliva’s buffering capacity can be influenced by diet (systematically), however, this effect was apparently, temporary ( Afonsky, 1961). The use of certain drugs affect salivary secretion and hence, buffering capacity (Osterberg, Landahland Hedegard, 1984). Some medication such as the administration of Diamox for example, decresses the bicarbonate and sodium content of saliva with resultant decrease in its buffering power (Afonsky, 1961) Saliva’s pH values were significantly lower in children with ongoing cancer and in those cured of their malignant disease than in their age-matched controls (pajari, et al. 1989). As far as physiological conditions are concerned, it has been reported that salivary pH and buffer capacity decrease during pregnancy (Laine et al. 1988). Age play a significant role in lowering the pH of saliva. In general saliva pH values for a young populationare more alkaline than that of an older group (Osterberg, landahl and Hedegard, 1984).King Saud Universit

Growth and acid production profile of Streptococcus mutans 6715 in the presence of tannic acid.

Salvadora persica (Miswak) and certain related Nigerian chewing stick plants are used as a toothbrush substitute for oral hygiene. One of the proposed active substances in these chewing sticks is tannic acid, which has been shown to possess antibacterial and antifungal properties. This study was carried out to investigate the effect of tannic acid (TA) on the growth and acid production of Streptococcus mutans 6715. Various concentrations of TA prepared with trypticase soy broth were inoculated with Streptococcus mutans 6715 and incubated at 37oC. Growth was monitored by OD measured at specific intervals. In acid production experiment, cells of the bacterium were used as non-growing cell suspension in a combined buffer solution of 40 mM NaHCO3 and 6 mM K2HPO4 to which various concentrations of TA were added. Data showed that TA was bacteriostatic at concentrations of 10, 100, 200 and 300 mg/ml and bactericidal at 500 mg/ml. However, acid production of Streptococcus mutans 6715 was not affected by presence of TA. Growth inhibition of Streptococcus mutans 6715 demonstrated by this study suggests that tannic acid may play an important role in restricting plaque accumulation and hence dental caries.King Saud Universit

In Vitro pH Changes and Acid Profile Obtained during Metabolism of Dates by Oral Flora

Dates are a commonly eaten fruit in many Middle East and North American countries. Chemical analysis of this fruit by previous workers showed that it is rich in carbohydrates, proteins, amino acids and minerals. The acid-base changes, which occur when dates is metabolized by mixed oral bacteria was investigated. The results showed that despite the presence of nitrogenous substances in dates profound acidogenic response was obtained with the different types of the fruit and at different ripening stages. A variety of organic acids, which included lactic acid, acetic acid and propionic acid were produced during process.King Saud Universit

Microbiological Character Characteristics of Treated Adult Periodontitis Cases on Maintenance Care

The present study was due to analyze the subgingival microflora after after surgical treatment of severe adult periodontitis. Twenty eight patients participated in the study. They were selected to receive modified Widman flap surgery for at least single rooted teeth having attachment loss of more than 7 mm. Gingival crevices rangjng from 1-3 mm were sampled with paper points. Diluted samples were incubated in non-selective and selective media for identification of black pigmented Bacteroides (bpB) and Actinobacillus actinomycetemeomitans (Aa). Results revealed very low recovery of Aa while bpB were more frequently obsereved. It was concluded that the recovery of such organism at a low rate may not be indicative of recurrence of periodontaI disease.King Saud Universit

Effect of Aqueous Extract of Miswak on the in Vitro Growth of Candida Albicans

Chewing sticks (miswak) which are the roots of Salvadora persica plant have been used for centuries as oral hygiene tools In. many parts of the world particularly in Saudi Arabia. Many studies have demonstrated the antiplaque, antiperiopathic, anticaries and antibacterial effect of these sticks. This study was designed to investigate the antimycotic effect, if any, of the aqueous extract of the plant roots. Various concentrations of aqueous extract of miswak prepared with Sabouraud medium were inoculated with Candisa albicans (oral isolate), These were incubated at 37"C and the turbidity was determined by OD at 600 nm wavelength measured at specific intervals over a period of 48 h. Data show that the extract at a concentration of 15% and above, has a fungistatic effect for up to 48 h. This antimycotic effect was probably due to one or more of the root contents which included chlorine, trimethylamine, an alkaloid resin, and sulphur compounds.King Saud Universit

Electron microscopic demonstration of herpes simplex virus-i after up inoculation in rabbit

Herpes simplex virus-1 (HSl is recognized lo be the identifiable cause of herpes labialis in humans. The aim of the sent research was to demonstrate the viral particles in labial mucosa at different periods in rabbit after lip inoculation with HSl-1. Eight rabbits were lip inoculated with HSl'-1. They were then sacrificed al 3.7,14 and 21 days. Two rabbits were served as controls and were sacrificed at 3 and 14 days. The biopsy specimens were fixed in 2.5 % glutaraldehyde. processed and examined using the JEOL CX I 00 transmission electron microscope. The findings of the present work indicated that the viral particles of HSl'-/ were mainly detected within the nuclei and some in the cytoplasm of the epithelial, mesenchymal and Schwann cells in most of the specimens up lo 14 days. However, few viral particles were also evident in the nuclei of the epithelial cells in the 21 day specimens. The control specimens were devoid of any viral particles. In conclusion, the presence of HSl'-1 viral panicles in the nuclei of the epithelial, mesenchymal and nerve cells indicate that this type of virus is mainly restricted to these sites. Consequently, the present report revealed that the development of herpetic lesions in the selected animal model is similar lo herpetic infection in humans regarding the clinical and microscopic episodes.King Saud Universit