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BACKGROUND: Early childhood caries (ECC), a type of tooth decay that affects preschool children, is a complex chronic disease resulting from an imbalance of multiple risk factors and protective factors of tooth decay, over time. The antioxidant system in saliva is one of its defense mechanisms against disease agents. The pH of saliva also affects the integrity of the oral cavity, hence caries susceptibility. OBJECTIVE: The study assessed and compared the total antioxidant capacity (TAC) and pH of saliva in children with and without ECC. METHODS: Unstimulated whole saliva, using the passive drool method was obtained from children with and without ECC, matched for age and gender. The samples were analyzed for TAC using the phosphomolybdenum assay technique, and pH with a hand-held digital pH meter. Data was analyzed using the Statistical Package for Social Sciences (SPSS) version 21. Association between categorical variables was determined using Chi-square, while analysis of variance (ANOVA) was used to compare the means. The level of significance (p-value) was set at 5% (0.05). RESULTS: A total of 68 children were examined (34 with ECC and 34 without ECC). The mean TAC in the ECC group was (0.53± 0.2) which was higher than the mean TAC of (0.36± 0.1) in the group without ECC. The mean pH (6.17±0.5) in the ECC group was lower than the mean pH (6.74± 0.5) in the caries-free group. The difference was statistically significant, p value<0.001. CONCLUSION: The saliva samples of children with ECC contained higher mean TAC and lower pH values compared to those without, who had lower mean TAC and higher pH values. This suggests a relationship between antioxidant production and cariogenesis. There was a statistically significant positive correlation between TAC and the pH of saliva in children with ECC.

CONTEXTE: La carie de la petite enfance (CPE), un type de carie dentaire qui touche les enfants d'âge préscolaire, est une maladie chronique complexe résultant d'un déséquilibre de multiples facteurs de risque et de facteurs de protection contre la carie dentaire, au fil du temps. Le système antioxydant de la salive est l'un de ses moyens de défense. mécanismes contre les agents pathogènes. Le pH de la salive affecte également l'intégrité de la cavité buccale, d'où la susceptibilité aux caries. OBJECTIF: L'étude a évalué et comparé la capacité antioxydante totale (TAC) et le pH de la salive chez les enfants avec et sans CPE. METHODES: Salive entière non stimulée, en utilisant le La méthode de la bave passive a été obtenue auprès d'enfants avec et sans CPE, appariés en fonction de l'âge et du sexe. Les échantillons ont été analysés pour le TAC à l'aide de la technique de dosage du phosphomolybdène et le pH avec un pH-mètre numérique portatif. Les données ont été analysées á i'aide du paquet statistique pour les sciences sociales (SPSS) version 21. L'association entre les variables catégorielles a été déterminée à l'aide du chi carré, tandis qu'une analyse de variance (ANOVA) a été utilisée pour comparer les moyennes. Le niveau de signification (valeur p) a été fixé à 5 % (0,05). RESULTATS: Un total de 68 enfants ont été examinés. (34 avec ECC et 34 sans ECC). Le TAC moyen dans le groupe ECC était de (0,53 ± 0,2), ce qui était supérieur au TAC moyen de (0,36 ± 0,1) dans le groupe sans ECC. Le pH moyen (6,17 ± 0,5) dans le groupe ECC était inférieur au pH moyen (6,74 ± 0,5) dans le groupe sans carie. La différence était statistiquement significative, valeur p <0,001. CONCLUSION: Les échantillons de salive des enfants atteints de CPE contenaient un TAC moyen plus élevé et des valeurs de pH plus faibles par rapport à ceux sans TAC, qui avaient un TAC moyen plus faible et des valeurs de pH plus élevées. Ceci suggère une relation entre la production d'antioxydants et la cariogenèse. Il existait une corrélation positive statistiquement significative entre le TAC et le pH de la salive chez les enfants atteints de CPE. MOTS CLES: Carie de la petite enfance (CPE), Salive, pH, Capacité antioxydante totale (TAC).

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Essential oils are promising substitute for chemical pesticides with the inherent resistance by pests, environmental and health effects on humans. In this study, the chemical composition of essential oil extracted from Citrus sinensis peel was characterized, the insecticidal activities of the oil and its constituents against Callosobrunchus maculatus (Cowpea weevil) and Sitophilus zeamais (maize weevil) were investigated and the underlying insecticidal mechanism were elucidated. The essential oil was extracted by hydro-distillation and characterized using gas chromatography-mass spectrometry (GC-MS). Insecticidal activity was determined by contact and fumigant toxicity assay. The inhibitory effect of the oil and its constituents on acetylcholinesterase (AChE), Na+/K+-ATPase and glutathione-S- transferase (GST) activity were assayed using standard protocols. The total number of volatile compounds detected in C. sinensis essential oil was eighteen (18). d-limonene (59.3%), terpineol (8.31%) and linalool (6.88%) were the major compounds present in the essential oil. Among the tested essential oil compounds, terpineol showed highest contact toxicity against C. maculatus (LD50 =17.05 µg/adult) while 3-carene showed highest contact toxicity against S. zeamais (LD50 =26.01 µg/adult) at 24 h exposure time. Citral exhibited the highest fumigant toxicity against C. maculatus and S. zeamais with LC50 value 0.19 and 2.02 µL/L air at 24 h respectively. Acetylcholinesterase and Na+/K+-ATPase activities were significantly inhibited by C. sinensis oil and its constituents in both C. maculatus and S. zeamais as compared to control. This study indicates that C. sinensis essential oil and its constituents have potential to be developed into botanical pesticides.

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The decolorization and biodegradation of Reactive Blue 13 (RB13), a sulphonated reactive azo dye, was achieved under static anoxic condition with a bacterial strain identified as Proteus mirabilis LAG, which was isolated from a municipal dump site soil near Lagos, Nigeria. This strain decolorized RB13 (100mg/l) within 5h. The formation of aromatic amine prior to mineralization was supported by Fourier transform infrared spectrometry (FTIR), which revealed the disappearance of certain peaks, particularly those of the aromatic C-H bending at 600-800 cm(-1). Gas chromatography-mass spectrophotometry (GCMS) analysis of the dye metabolite showed the presence of sodium-2(2-formyl-2-hydroxyvinyl) benzoate, with a tropylium cation as its base peak, this suggested the breakage of naphthalene rings in RB13. The detection of azoreductase and laccase activities suggested the enzymatic reduction of azo bonds prior to mineralization. In addition, phytotoxicity studies indicated the detoxification of RB13 to non-toxic degradation products by this strain of P. mirabilis LAG.

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In addition to being a widely consumed vegetable in West Africa, the leaves extract of Telfairia occidentalis is believed to have beneficial health effects and is used in tradomedical preparations. The effect of saline extract of T. occidentalis leaves on sickle and normal erythrocytes membrane stability was investigated. Human erythrocytes exposed to hypotonic and heat stress, by incubation in a buffered hypotonic medium at 56 degrees C, were stabilized by the extract in a doze dependent manner. The maximum stability was 72.3 +/- 3.1% and 55.0 +/- 4.1% for the sickle and normal erythrocytes membrane respectively (p < 0.0001). This study indicates that T. occidentalis has human erythrocyte membrane stabilizing activity. In addition the marked difference in the observed effect between the normal and sickle erythrocytes membranes suggests that pharmacogenetic factors may be involved in the response to herbal preparations.

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The genetic basis of the fungicidal activity of strains of Lactobacillus brevis and L. fermentum isolated from indigenous fermented foods was determined. A 5.5-kb plasmid was isolated from L. brevis while L. Fermentum was found to harbor no plasmid. Plasmid curing indicated no correlation between the plasmid and the fungicidal activity of the Lactobacillus species. The fungicidal activity of the isolated organisms can be supposed to be mediated by the chromosome. No antibiotic resistance genetic markers were detected on the plasmid and hence it was classified as cryptic.

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