EFECTO DEL QUITOSANO EN EL DESARROLLO Y MORFOLOGÍA DE ALTERNARIA ALTERNATA (FR.) KEISSL

The potential of low and medium molecular weight chitosan (LMWC, MMWC) at five concentrations (0.5, 1.0, 1.5, 2.0 and 2.5% w/v) and high molecular weight chitosan (HMWC) at four concentrations (0.5, 1.0, 1.5 and 2.0 w/v) to inhibit the fungus Alternaria alternata was evaluated. MMWC at 2.5% w/v inhibited mycelial growth of A. alternata up to 50.6%, whilst 0.5, 1.0 and 1.5% doses at the three molecular weight promoted mycelial growth. Sporulation was affected at 2.5% concentration by LMWC and MMWC. Percentage of spore germination was not affected by concentration but it was affected by molecular weight of chitosan. An inverse relationship was observed between germination and molecular weight. Mycelial dry weight was inhibited by all concentrations and type of chitosan evaluated. Observations at the scanning electron microscopy showed diverse alterations in hyphaes such as swelling, depression, and distortion by effect of chitosan.Se evaluó la capacidad in vitro del quitosano de bajo y medio peso molecular (QBPM, QMPM) a cinco concentraciones (0,5, 1,0, 1,5, 2,0 y 2,5% p/v) y alto peso molecular (QAPM) en cuatro concentraciones (0,5, 1,0, 1,5 y 2,0% p/v) para inhibir el hongo Alternaria alternata. El QMPM a la concentración de 2.5%, inhibió el crecimiento del micelio de A. alternata en un 50,6%, mientras que a las concentraciones de 0,5, 1,0 y 1,5% en sus tres pesos moleculares promovió el crecimiento del micelio. La esporulación fue afectada a concentración de 2,5% por el QBPM y el QMPM. El porcentaje de germinación de esporas no fue afectado por las concentraciones, pero sí por los pesos moleculares. Se observó una relación inversa entre la germinación y el peso molecular. El peso seco del micelio fue inhibido con todas las concentraciones y tipos de quitosano evaluados. La observación de hifas a través del Microscopio Electrónico de Barrido mostró diversos daños como hinchazón, depresiones, y distorsiones por efecto del quitosano

Conservación de productos hortofrutícolas mediante el uso de nanopartículas de quitosano y agentes naturales

Actualmente se buscan nuevas alternativas amigables con el ambiente que permitan la conservación de productos agrícolas expuestos al deterioro durante la cosecha, transporte y distribución en el mercado para su venta con la subsecuente reducción de sus atributos de calidad, fisiológicos y propiedades sensoriales, aunados a la manifestación de microorganismos patógenos. En este sentido, se presenta el estado del arte del uso de recubrimientos nanoestructurados de nanopartículas de quitosano con agentes naturales, sus beneficios y un enfoque académico, industrial y gubernamental del uso de la nanoagrotecnología, así como las perspectivas de esta técnica para la conservación de frutas y hortalizas como una solución viable

Corn-Starch-Based Materials Incorporated with Cinnamon Oil Emulsion: Physico-Chemical Characterization and Biological Activity

Active packaging represents a large and diverse group of materials, with its main role being to prolong the shelf-life of food products. In this work, active biomaterials based on thermoplastic starch-containing cinnamon oil emulsions were prepared by the compression molding technique. The thermal, mechanical, and antifungal properties of obtained materials were evaluated. The results showed that the encapsulation of cinnamon oil emulsions did not influence the thermal stability of materials. Mechanical resistance to break was reduced by 27.4%, while elongation at break was increased by 44.0% by the addition of cinnamon oil emulsion. Moreover, the novel material provided a decrease in the growth rate of Botrytis cinerea by 66%, suggesting potential application in food packaging as an active biomaterial layer to hinder further contamination of fruits during the storage and transport period

in vitro response of Colletotrichum to chitosan. Effect on incidence and quality on tropical fruit. Enzymatic expression in mango

Colletotrichum is considered one of the fungal genera with the greatest diversity of species of phytopathogenic fungi and with a wide range of hosts including tropical fruits. In this study, the concentration of chitosan applied was a key factor in the in vitro inhibition of the three Colletotrichum isolates with the most sensitive being the one from banana. Germination was the development stage most affected by the application of this polymer. At the end of 10 days of storage, control of anthracnose in soursop, mango and banana fruit was considerable with the application of 1 % chitosan, with 80 to 100 % inhibition. Likewise, the ripening process of fruit with and without chitosan was generally similar. Activity of the peroxidase (POD) and polyphenol oxidase (PPO) enzymes was observed only in fruit of mango cv. 'Tommy Atkins,' inoculated and non-inoculated with C. gloeosporioides, the activity of both enzymes was higher in the chitosan treatments and the 1.0 % concentration was able to induce gene expression of POD and PPO, occurring until 24 h

Physical-Chemical Evaluation of Active Food Packaging Material Based on Thermoplastic Starch Loaded with Grape cane Extract

The aim of this paper is to evaluate the physicochemical and microbiological properties of active thermoplastic starch-based materials. The extract obtained from grape cane waste was used as a source of stilbene bioactive components to enhance the functional properties of thermoplastic starch (TPS). The biomaterials were prepared by the compression molding technique and subjected to mechanical, thermal, antioxidant, and microbiological tests. The results showed that the addition of grape cane extract up to 15 wt% (TPS/WE15) did not significantly influence the thermal stability of obtained biomaterials, whereas mechanical resistance decreased. On the other side, among all tested pathogens, thermoplastic starch based materials showed antifungal activity toward Botrytis cinerea and antimicrobial activity toward Staphylococcus aureus, suggesting potential application in food packaging as an active biomaterial layer

TRANSFORMED CELL SUSPENSION CULTURE OF GALPHIMIA GLAUCA PRODUCING SEDATIVE NOR-FRIEDELANES.

http://redalyc.uaemex.mx/redalyc/pdf/612/Resumenes/61214206005_Abstract_2.pd

INHIBITORY EFFECT OF ESSENTIAL OILS AGAINST COLLETOTRICHUM GLOEOSPORIOIDES AND RHIZOPUS STOLONIFER IN STORED PAPAYA FRUIT AND THEIR POSSIBLE APPLICATION IN COATINGS.

http://www.sciencedirect.com/science/article/pii/S092552141000069

RESPONSE OF GLADIOLUS (GLADIOLUS SPP) PLANTS AFTER EXPOSURE CORMS TO CHITOSAN AND HOT WATER TREATMENTS.

http://www.sciencedirect.com/science/article/pii/S030442380900132

USE OF CHITOSAN-BASED EDIBLE COATINGS IN COMBINATION WITH OTHER NATURAL COMPOUNDS, TO CONTROL RHIZOPUS STOLONIFER AND ESCHERICHIA COLI DH5Α IN FRESH TOMATOES

http://www.sciencedirect.com/science/article/pii/S0261219412000531