With the introduction of the new European Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) system,
this number is likely to increase dramatically. The aim of this work was to test the acute toxicity of a number of anionic, cationic and non-ionic surfactants to embryos of the zebrafish (Danio rerio), over 48 hours, as a possible alternative to the standard 96-hour fish acute test. We measured the toxicities of 15 surfactants, and compared the results to previously generated adult D. rerio LC50 data (or other fish species, if these data were not available). Comparison of the LC50 data showed that embryos appear to be as sensitive to cationic RG-7388 mw and non-ionic surfactants as the adult fish, but possibly are more sensitive to anionic surfactants. Toxicity testing with the embryo test can be carried out more quickly than with the adult test, uses much less space and media, requires less effort, and therefore can be performed at a reduced cost. The embryo test may also uncover additional sub-lethal effects, although these were not
observed for surfactants. The data presented here show that the 48-hour embryo test can be considered as a suitable alternative to the adult acute fish test for surfactants.”
“This study proposes a bioprospection methodology regarding the antimicrobial potential of plant extracts against bacteria with cariogenic relevance. Sixty extracts were obtained from ten plants – (1) Jatropha weddelliana, (2) Attalea phalerata, (3) Buchenavia tomentosa, (4) Croton doctoris, (5) Mouriri elliptica, Selisistat Epigenetics inhibitor (6) Mascagnia benthamiana, (7) Senna aculeata, (8) Unonopsis guatterioides, (9) Allagoptera Screening Library chemical structure leucocalyx and (10) Bactris glaucescens – using different extraction methods -(A) 70 degrees ethanol 72 h/25 degrees C, (B) water 5 min/100 degrees C, (C) water 1 h/55 degrees C, (D) water 72 h/25 degrees C, (E) hexane 72 h/25 degrees C and (F) 90 degrees ethanol 72 h/25 degrees C. The plants were screened for antibacterial activity at 50 mg/ml using the agar well diffusion test against Actinomyces naeslundii
ATCC 19039, Lacto-bacillus acidophilus ATCC 4356, Streptococcus gordonii ATCC 10558, Streptococcus mutans ATCC 35688, Streptococcus sanguinis ATCC 10556, Streptococcus sobrinus ATCC 33478 and Streptococcus mitis ATCC 9811. The active extracts were tested to determine their minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), cytotoxicity and chemical characterization. Forty-seven extracts (78%) were active against at least one microorganism. Extract 4A demonstrated the lowest MIC and MBC for all micro-organisms except S. gordonii and the extract at MIC concentration was non-cytotoxic. The concentrated extracts were slightly cytotoxic. Electrospray ionization with tandem mass spectrometry analyses demonstrated that the extract constituents coincided with the mass of the terpenoids and phenolics. Overall, the best results were obtained for extraction methods A, B and C.