Antimicrobial activity of Streblus asper leaf extract.

Bactericidal activity was found in the 50% ethanol (v/v) extract of Streblus asper leaves. The extract possessed a selective bactericidal activity towards Streptococcus, especially to Streptococcus mutans which has been shown to be strongly associated with dental caries. The extract had no effect on cultures of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa, Staphylococcus coagulase positive, Staphylococcus coagulase negative, Serratia marcescens, Klebsiella pneumoniae, Enterobacter, Pseudomonas aeruginosa, Burkholderia pseudomeallei and Candida albicans. The minimum growth inhibitory concentration and the minimum bactericidal concentration of S. asper extract against 10(8) CFU/mL of S. mutans was 2 mg/mL. The active compound is partially polar, partially heat labile, precipitated by 80% ammonium sulphate, and possesses a molecular weight larger than 10 000 Da. The potential for using S. asper extract as a natural product for controlling dental caries is discussed.

Analyses of salivary components in leukemia patients receiving chemotherapy.

We analyzed several salivary components in stimulated whole saliva from patients with acute leukemia who were undergoing chemotherapy. Saliva samples were collected at the time of diagnosis and longitudinally during the treatment period. Data analyses showed that patients with leukemia had significantly higher peroxidase and amylase activity and elevated concentrations of total protein at the time of diagnosis. After induction chemotherapy these parameters returned to normal values and remained constant during the observation period. At the time of diagnosis no significant differences in thiocyanate (SCN-) concentrations were found in saliva samples from control subjects and patients with leukemia. Treatment with cytotoxic agents resulted in granulocytopenia and a concomitant decrease in the SCN- concentration in saliva. The function of the salivary peroxidase system is impaired by the decrease in SCN- concentration, which may be a contributing factor to some of the oral complications that occur in patients undergoing chemotherapy.