In this study, a partial purification and characterization of the lectins from two varieties of Phaseolus coccineus (black and purple ayocote bean) was carried out. A partial purification of the lectins was performed by affinity chromatography on fetuin-agarose. The lectins’ characterization showed that the hemagglutination activity was only inhibited by the fetuin and that the saccharides (mono-, di- and tri-saccharides) do not influence their hemagglutination capacity. A difference in the relative molecular weight between the two Phaseolus varieties was observed, 28.5 kDa for the black variety and 30.6 kDa for the purple variety. In the lectins of both Phaseolus varieties, ions were detected in their structure and influenced their hemagglutination activity, principally to the ion Ca+2; on the other hand, only the lectins of the purple variety of the Phaseolus, had a detectable ion, Cu+2. The lectins showed thermostability in the temperature range of 25 and 70 °C, on the other hand, in the pH range between 3 and 10, the lectins showed hemagglutination activity. According to the obtained results, the structural differences between the lectins obtained from both Phaseolus varieties influence their hemagglutination activity.

Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo intemperizados en suelos y sedimentos (Biodegradation modeling of sludge bioreactors of total petroleum hydrocarbons weathering in soil and sediments)

No abstract

Recently, the utilisation of essential oils extracted from spices has been garnering interest due to their phytochemical constituents which could be extracted using various techniques. Studies have demonstrated antimicrobial activities from essential oils against foodborne pathogens, and thus, their application has been considered to be a possible preservative for foods. Pimenta dioica is a type of aromatic plant, and its essential oil is is rich in eugenol, a phenolic compound with wide antimicrobial spectrum. Other bioactive compounds in P. dioica extract include glycosides, alkaloids, carbohydrates, proteins, flavonoids, and tannins. The incorporation of essential oils into food is limited because they have an intense aroma, and might affect consumer acceptance. Therefore, nanotechnology is applied as a tool to rectify this limitation, and it is now possible to apply essential oils in active packaging, or to encapsulate them in biodegradable materials or edible coatings with controlled release. However, there is little information on the interaction of nanoencapsulated bioactive composites, and thus, it is essential to assess the viability of biomaterials before their use. The objective of this work is to show the use of the essential oil of Pimenta dioica and its phytochemical composites in a general way for its potential application in food technology.

Ethanol oleoresins obtained from orange peel, pea pod, or pomegranate peel were employed to enrich soybean oil before elaborating two types of oleogels, one made with candelilla wax, another made with a mixture of celluloses derivatives, in order to determine their effect on oleogel oxidative stability. Orange peel oleoresin obtained a higher amount of polyphenols as catechol acid equivalent (9.09 meq/g), as compared to pea pod oleoresin or pomegranate peel (8.80 and 8.55, respectively), although pomegranate peel presented the higher TEAC (1.67, twice than the other samples). Oleogels elaborated with celluloses were presented better oxidative stability (oxidative rancidity and peroxide index) as compared to samples elaborated with candelilla wax, since waxes minor constituents employed as oleogelators could promote prooxidant activity. Samples with pomegranate oleoresin presented enhanced oxidative stability. Candelilla wax has a more marked effect on the oleogels thermal properties of due to their influence on fatty acids crystallization, because in celluloses oleogels the mechanism of gelation does not imply the formation of a highly ordered secondary structure. This finding opens the possibility to, on one hand, use oleoresins to enhance the oxidative stability of oleogels; and on the other hand, to select the oleogelator, waxes, or celluloses, based on thermal properties and other aspects, depending on the further application of oleogel thinking in oleogel thermoreversible capacity.