No abstract

Ethylene (C 2 H 4 ) acts as a plant hormone, growth regulator that has a number of effects on the growth. Ethylene accelerates respiration, leading to maturity and also softening and ripening of many kinds of fruits. Although ethylene has some positive effects, it is often hazardous to the quality and shelf-life of fruits and vegetables. The removal of ethylene and/or inhibition of the effect of ethylene in stored environments is fundamental to maintaining postharvest quality of climacteric produce. In this study, the efficiency of a Chilean natural zeolite (NZ-Ch) against a commercial Na + montmorillonite (Cloisite Na + ) was studied. The aluminosilicate characterization (XDR, FTIR, EGME, CEC, chemical composition) indicates that natural Chilean zeolite belongs to mordenite group. Elemental chemical analysis indicated that compensating ions, were sodium for MTNa + and calcium, sodium and potassium for NZ-Ch, and in both aluminosilicates copper was present in their composition. Ethylene adsorption kinetics were fitted to a pseudo-second order model. The rate constant of the ethylene adsorption was nearly double for NZ-Ch compared with MtNa

Bioactive compounds and nutritional characterization in three genotypes of mashua tubers (Tropaeolum tuberosum Ruiz and Pavón) from different agroecological areas of the Peruvian highlands (3747 at 3888 meters above sea level) were studied. The studied genotypes from different agroecological areas significantly differed for vitamins, amino acids, and bioactive compounds. However, the nutritional characteristics of yellow, purple, and yellow-purple mashua remained unaffected. Its tubers were shown to be important sources of protein and fiber. The nutritional analysis revealed high phosphorus and potassium values, as well as considerable amounts of vitamin C. The amounts of total free amino acids in the genotypes ranged from 2.73 ± 0.450  mg/g dry matter (DM) to 6.825 ± 0.450  mg/g DM. Important total anthocyanins, total flavonoids, total phenolics, tannin content, and antioxidant activity values were obtained from purple genotype. Unexploited colored mashua tubers are proposed as a valuable natural source of phenolics and anthocyanins with high antioxidant activity.