Mango peel as a potential enzyme inducer in Trichoderma harzianum: a strategy for cariogenic biofilm degradation and reuse of industrial waste

Water-insoluble exopolysaccharides (I-EPS) are a virulence factor for dental biofilms. It has already been demonstrated that mango pulp induces the secretion of glucan-hydrolytic enzymes in the fungus Trichoderma harzianum, and that they have an effect on I-EPS from young biofilms. Aim: Evaluate the effect of mango peel as an enzyme inducer in T. harzianum, and the effect of enzymes secreted on mature biofilms. Methods: Fractions of the peel (PL) and ethanol-precipitated pulp (PP) of Tommy Atkins mangoes were sterilized and added to a culture medium containing T. harzianum for induction of hydrolytic enzymes. After 192 h, the culture medium was centrifuged and the supernatant (enzyme extract) was used as treatment on S. mutans biofilms (n=9): a) NaCl 0.9 %; b) 0.12 % chlorhexidine digluconate; and c) extract of enzymes induced by PL or PP. Acidogenicity, bacterial viability, quantification of insoluble polysaccharides, and three-dimensional analysis of the biofilm by scanning electron microscopy (SEM) was performed. Data were analyzed by ANOVA followed by the Tukey test (α=5 %). Results: The hydrolytic enzymes did not alter the metabolism or bacterial viability of the biofilm (p<0.05). Although the images obtained by SEM suggest some degree of matrix degradation, the quantification of I-EPS for the PL and PP groups did not differ from the control group (p>0.05), suggesting a slight effect on the disorganization of the mature S. mutans biofilm. Conclusion: The results suggest that mango peel fraction can induce secretion of mutanase by T. harzianum, however in an insufficient amount to generate significant degradation on cariogenic biofilm.

Clinical and biochemical evaluation of the saliva of patients with xerostomia induced by radiotherapy

Foram avaliados alguns aspectos clínicos e algumas propriedades bioquímicas salivares de 21 pacientes, antes e após o tratamento radioterápico para câncer de cabeça e pescoço (grupo experimental) e de 21 pacientes sem câncer (grupo controle). O fluxo salivar foi avaliado pelo tempo necessário (segundos) para produção estimulada de 2 ml de saliva e a capacidade tamponante determinada frente à utilização de um método colorimétrico simples. A concentração de proteína total salivar foi determinada pelo método de Bradford4. A atividade da amilase foi mensurada através dos açúcares redutores liberados e quantificados pelo método do ácido dinitrossalicílico utilizando a glicose como substrato. O perfil eletroforético foi avaliado em gel de poliacrilamida (SDS-PAGE 12%) para amostras salivares contendo 5 mg de proteína. Foi observada, no grupo experimental, redução estatisticamente significativa (p < 0,01) para o fluxo salivar (162,47 s ± 28,30 antes e 568,71 s ± 79,75 após) e para a capacidade tamponante (pH 5,45 ± 0,14 antes e 4,40 ± 0,15 após). Não foi observada alteração estatisticamente significativa na concentração de proteína. A atividade específica da a-amilase foi significativamente diminuída (p < 0,01) (856,6 ng/mg ± 88,0 antes e 567,0 ng/mg ± 120,6 após). No perfil eletroforético, foram observadas diferenças nas bandas protéicas, principalmente na faixa de peso molecular de 72.000 a 55.000 Da. Clinicamente, os pacientes com xerostomia induzida pela radioterapia apresentaram aumento de lesões na mucosa.

Evaluation of the influence of cetylamine fluoride and sodium fluoride on acid production by S. mutans

The acidogenic character of Streptococcus mutans has been pointed out as one of the most important physiological aspects associated with dental caries establishment. Fluoride is a key component of oral health promotion. Amine fluorides (AmF) have been used in products such as mouth rinses, toothpastes, gels and other topical fluoride agents for over 30 years in several European countries. In Brazil, the use of such substances was limited to toothpaste until August 2000, when a new resolution was published to approve the use of three AmFs in mouth rinses and other formulations for odontological purposes. In this report the influence of cetylamine fluoride (CAmF) and sodium fluoride (NaF) on acid production...