Perfil fitoquímico e determinação da atividade antimicrobiana de Syzygium cumini (L. ) Skeels (Myrtaceae) frente a microrganismos bucais / Phytochemical profile and determination of antimicrobial activity of Syzygiumcumini (L. ) Skeels (Myrtaceae) against oral microorganisms

RESUMO Este estudo teve como objetivo determinar o perfil fitoquímico e avaliar a atividade antimicrobiana in vitro do extrato etanólico da casca do caule de Syzygium cumini(L.) Skeels frente a microrganismos bucais. O perfil fitoquímico do extrato foi traçado através da determinação espectrofotométrica quantitativa para verificar o teor de taninos, flavonóides, saponinas e polifenóis. A atividade antimicrobiana foi determinada através da Concentração Inibitória Mínima (CIM), por meio da técnica de microdiluição em caldo, utilizando-se as seguintes linhagens de microrganismos: Streptococcus mutans (25175), Streptococcus oralis (10557) e Candida albicans (10231). Uma quantidade apreciável de fitocontituintes foi observada, especialmente de taninos (100,58 ± 1,81). Os extratos apresentaram atividade antimicrobiana inibindo o crescimento das linhagens em estudo, destacando-se essa atividade sobre o crescimento de C. albicans (CIM=250 µg/mL). Já as CIMs para Streptococcus foram baixas. Diante dos resultados expostos, pode-se concluir que o perfil fitoquímico foi traçado e que, dentre os microrganismos testados, o extrato etanólico da casca de S. cumini apresentou forte potencial de inibição sobre o crescimento de C. albicans e fraca inibição frente aos Streptococcus testados. Este estudo sugere que mais pesquisas devem ser realizadas dando continuidade à bioprospecção, por meio de análises experimentais com essa espécie vegetal, objetivando, no futuro, que essa planta possa ser utilizada clinicamente para tratar candidose bucal.

ABSTRACT This study aimed to determine the phytochemical profile and to evaluate the in vitro antimicrobial activity of the ethanol extract of stem bark of Syzygium cumini (L.) Skeels against oral microorganisms. The phytochemicalprofile of the extract was traced through a quantitative spectrophotometric determination in order to check the tannin, flavonoids, saponins, and polyphenols content. The antimicrobial activity was determined through minimum inhibitory concentration (MIC) by the broth microdilution technique, using the following strains of microorganisms: Streptococcus mutans (25175), Streptococcus oralis (10557) and Candida albicans (10231). An appreciable amount of fitocontituintes was observed, particularly the tannin (100.58 ± 1.81). The extracts showed antimicrobial activity, inhibiting the growth of the strains under study, with this activity being more intense on the growth of C. albicans ( MIC = 250 mg / mL). On the other hand, the MICs of the Streptococcus were low. In face of the mentioned results, we can conclude that the phytochemical profile was traced and that, among the tested microorganisms, the ethanol extract of S. cumini bark showed strong potential to inhibit the growth of C. albicans and weak inhibition against the Streptococcus tested. This study suggests that more research should be done by proceeding with the bioprospecting, through experimental tests with this plant`s species, aiming that in the future this substance can be used clinically for the treatment of oral candidiasis.

Occult hepatitis B virus infection in liver transplant patients in a Brazilian referral center

Estimates of occult hepatitis B virus (HBV) infection prevalence varies among different studies depending on the prevalence of HBV infection in the study population and on the sensitivity of the assay used to detect HBV DNA. We investigated the prevalence of occult HBV infection in cirrhotic patients undergoing liver transplantation in a Brazilian referral center. Frozen liver samples from 68 adults were analyzed using a nested polymerase chain reaction assay for HBV DNA. The specificity of the amplified HBV sequences was confirmed by direct sequencing of the amplicons. The patient population comprised 49 (72.1%) males and 19 (27.9%) females with a median age of 53 years (range=18-67 years). Occult HBV infection was diagnosed in three (4.4%) patients. The etiologies of the underlying chronic liver disease in these cases were alcohol abuse, HBV infection, and cryptogenic cirrhosis. Two of the patients with cryptic HBV infection also presented hepatocellular carcinoma. Markers of previous HBV infection were available in two patients with occult HBV infection and were negative in both. In conclusion, using a sensitive nested polymerase chain reaction assay to detect HBV DNA in frozen liver tissue, we found a low prevalence of occult HBV infection in cirrhotic patients undergoing liver transplant, probably due to the low prevalence of HBV infection in our population.

Estudo farmacognóstico das raízes de Jacaranda decurrens Cham. (carobinha)

Este trabalho estabelece parâmetros farmacognósticos para as raízes de Jacaranda decurrens Cham., Bignoniaceae, conhecida na medicina popular como carobinha. Características morfológicas e histológicas, prospecção fitoquímica, teor de cinzas e de açúcares redutores são descritos. Encontrou-se presença de esteróides/triterpenos, açúcares redutores, amido, mucilagem e saponinas. O teor de cinzas totais foi de 2,21 por cento, e insolúveis em ácido de 0,63 por cento; a umidade, de 6,42 por cento e o teor de açúcares redutores foi de 2,77 por cento.

This work stablishes pharmacognostic parameters to Jacaranda decurrens Cham. roots, Bignoniaceae, known in the folk medicine as carobinha. Morphological and histological characteristics, phytochemical tests, ash and reducing sugars contents are descripted. The results showed steroids/triterpenes, sugars reducers, starch, mucilage and saponinas presence; the tenor of total ashes was of 2,21 percent, and insoluble in acid of 0,63 percent; the humidity of 6,42 percent and the tenor of sugars reducers was of 2,77 percent.