This work evaluated the production of dehydrated mangoes (Mangifera indica L.) and the effectiveness of ultrasonic-assisted osmotic dehydration on the drying kinetics of mangoes. Cube shaped mango samples were pretreated using ultrasound-assisted osmotic dehydration (UAOD) and dried in a circulating drying oven. An experimental design was created to evaluate the effect of pretreatment time and osmotic solution concentration on the water loss and sugar gain in the osmotic dehydration and on the drying time. The ultrasonic pretreatment was carried out in a bath ultrasound operating at 25 kHz and outputting 55 W/m 3 of power. Osmotic solution ranging from 0 to 500 kg sucrose/m 3 was applied in the treatments, and air drying was carried out at 60°C. A mathematical model was developed for the osmotic pretreatment, and Fick's law was used to model the air-drying process. The mass transfer coefficients were estimated for the ultrasonicassisted osmotic dehydration, and the apparent water diffusivity was estimated for the air-drying process. The mass transfer coefficient ranged from 0.017 to 0.109 m 2 /s and the resistance to mass transfer at the surface ranged from 0.26 9 10 -6 to 1.22 9 10 -6 m 2 /s on the UAOD, while the apparent water diffusivity during air drying ranged from 5.94 9 10 -9 to 8.41 9 10 -9 m 2 /s. Mangoes presented a different behavior when compared to other fruits. The ultrasonic pretreatment was effective only when associated with an osmotic solution at 500 kg sucrose/m 3 .

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The Phyllanthus genus is widely distributed in tropical and subtropical areas of the world and present several pharmacological applications. Drought is a restrictive factor for crop development and production, and is becoming a severe problem in many regions of the world. The species Phyllanthus amarus and Phyllanthus niruri were subjected to drought stress for varying periods of time (0, 3, 5, 7, and 10 days), and afterwards, leaves were collected and evaluated for physiological and biochemical responses, such as oxidative stress markers and drought-associated defense mechanisms. Results show that P. amarus has an endogenously higher level of variables of the oxidative/antioxidant metabolism, and P. niruri presents the most significant changes in those variables when compared to control and stressed plants. For both Phyllanthus species, drought stress induces higher levels of organic acids such as malic, succinic, and citric acids, and amino acids such as proline, GABA, alanine, and valine. Moreover, P. niruri plants respond with greater glucose and corilagin contents. Therefore, considering the evaluated metabolic changes, P. amarus is better adapted to drought-stress, while P. niruri presents an acclimation strategy that increases the corilagin levels induced by short-term drought stress.

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