Quinolizidine alkaloids and the oil were recovered from seeds of bitter lupin,Lupinus mutabilis, by 2 extractions using hexane as the only organic solvent, Ground and flaked lupin seed was extracted first with hexane, which recovers the oil and those alkaloids that occur as free bases. Subsequently, the hexane‐insoluble salts of the alkaloids retained in the defatted flakes were converted into hexanesoluble free bases by treatment with aq sodium carbonate or ammonium hydroxide and removed by another extraction with hexane. A low‐alkaloid proteinaceous meal was obtained with practically no loss of protein. The alkaloids dissolved in the oil were completely recovered by extraction with aq hydrochloric acid.

Purpose: To assess the effect of acid hydrolysis on the degree of acetylation, crystallinity, and molecular weight of chitin obtained from shrimp heads as well as to evaluate their tableting properties. Methods: The effect of acid hydrolysis conditions such as reaction temperature (46, 60, 80, 100, 114°C), hydrochloric acid concentration (4.6, 6, 8, 10 and 11.4 M) and reaction time (0.6, 2, 4, 6 and 7.4 h) were examined. The degree of acetylation and molecular weight were found by Fourier transform spectroscopy (FT-IR) and viscometry methods, respectively. The degree of crystallinity degree and its compact tensile strength were determined by x-ray and Fell & Newton methods, respectively. Results: The combined effect of high temperature (> 80 o C), HCl concentration (> 2 M) and reaction time (> 4 h) led to high depolymerization, reduction in degree of

Silver nanoparticles have been obtained by colloidal synthesis using two different reducing agents: ascorbic acid and ethylene glycol. The colloids have been characterized by UV-Vis Spectroscopy, atomic absorption and transmission electron microscopy (TEM). The UV-visible spectra show the typical peak with a maximum ranging between 390-420 nm, due to the plasmon resonance of spherical silver nanoparticles. TEM micrographs show non-aggregated spherical silver nanoparticles whit diameters between 30 and 50 nm. The antibacterial effect was tested in three different bacteria cultures: Escherichia coli (gram negative), Staphylococcus epidermidis (gram positive) and dental plaque, which were grown in Mueller-Hinton agar. For comparative purposes the bactericidal effect of silver nitrate was also evaluated. Inhibition index (IIC) was calculated, obtaining satisfactory results for the three kinds of microorganism when silver nanoparticles are used.