Mineral nutrition and adventitious rooting in microcuttings of Eucalyptus globulus

We characterized the adventitious rooting response of Eucalyptus globulus Labill. to various concentrations of calcium, nitrogen, phosphorus, iron, manganese, zinc, boron and copper. The parameters analyzed were percent rooting, root number, root length and mean rooting time. Root number and root length were significantly affected by mineral nutrition, whereas mean rooting time and rooting percentage seemed to be closely related to auxin availability. Root number was affected by calcium, nitrogen source and zinc, whereas root length was influenced by concentrations of phosphorus, iron and manganese, and by nitrogen source. Based on these results, we evaluated various combinations of several concentrations of these minerals in each rooting phase. Cuttings that were rooted in an optimized mineral nutrient medium and acclimatized to ex-vitro conditions for two months showed significantly higher survival after transplanting and drought stress than cuttings rooted in basal medium and treated in the same way.     

Inhibition of trypsin by condensed tannins and wine

Phenolic compounds are abundant vegetable secondary metabolites in the human diet. The ability of procyanidin oligomers and wine polyphenols to inhibit trypsin activity was studied using a versatile and reliable in vitro method. The hydrolysis of the chromogenic substrate N-benzoyl-d,l-arginine-p-nitroanilide (BApNA) by trypsin was followed by spectrophotometry in the presence and absence of condensed tannins and wine. A clear relationship between the degree of polymerization of procyanidins and enzymatic inhibition was observed. Trypsin activity inhibition was also detected in several types of wine. In general, the inhibition increased with the concentration of phenolic compounds in wines. These results may be relevant when considering these compounds as antinutritional factors, thereby contributing to a reduced absorption of nutrients.     

Volumetric properties of sunflower methyl ester oil at high pressure

Biodiesel is an alternative to diesel oil (DO), because it is a fuel obtained from renewable resources that has lower emissions than DO. Biomass production should promote agricultural activity to obtain fuels for the transport sector. The study of the behavior of biodiesel at varying pressure and temperature is very interesting because diesel engines are mechanical systems that work with fuels submitted to high pressure. The specific volume, isothermal compressibility, and cubic expansion coefficients of refined sunflower methyl ester oil (SMEO) and unrefined sunflower methyl ester oil (URSMEO) were obtained and compared with those of DO from 0.1 to 350 MPa and 288.15 to 328.15 K. This work shows that oil refinement did not significantly modify any of the properties studied of the final biodiesel. Compared with DO, both SMEOs were about 6% denser, whereas isothermal compressibility and cubic expansion coefficients were bigger or smaller for DO depending on pressure and temperature.     

Anthocyanins present in selected tropical fruits: acerola, jambolão, jussara, and guajiru

Many tropical fruits are rich in anthocyanins, though limited information is available about the characterization and quantification of these anthocyanins. The identification and quantification of anthocyanin pigments in four tropical fruits were determined by HPLC-MS/MS. Fruits studied included acerola (Malphigia emarginata), jussara (Euterpe edulis), jambol?o (Syzygium cumini), and guajiru (Chrysobalanus icaco). All four fruits were found to contain anthocyanin pigments. Anthocyanidin backbones included cyanidin, delphinidin, peonidin, pelargonidin, petunidin, and malvidin. Guajiru contained several acylated forms, while acerola, jussara, and jambol?o contained only nonacylated glycosides. These results demonstrate that these tropical fruits are rich in anthocyanins and that the anthocyanins are widely ranging in anthocyanidin backbone, glycosylation, and acylation.