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The physicochemical and nutritional characteristics of Colocasia antiquorum (taro coconut or Chinese taro) starch cultivated in Oaxaca, Mexico, were determined. The granules of Colocasia antiquorum presented a truncated ellipsoidal shape. The chemical composition analysis showed levels of moisture, ash, protein, fat, fiber, and NFE in a dry base of 10.29, 0.18, 2.0, 0.05, 0.01, and 97.76, respectively, as well as amylose and amylopectin contents of 13.05 and 86.95%, respectively. Gelatinization temperatures, onset (To), peak (Tp), and final (Tf), were 72.86, 82.91, and 93.05°C, respectively. Solubility, swelling power (SP), and water absorption capacity (WAC) correlate directly with increments in temperature. Transmittance value (% T) for taro coconut was 0.3% and its apparent viscosity ranged from 100 to 150 cp. The nutritional characterization of Colocasia antiquorum’s starch amounted to 97.88% of total starch (TS), while available (AS) and resistant starch (RS) were 93.47 and 3.70%, respectively. Colocasia antiquorum, grown in Oaxaca, Mexico, is an unconventional source of starch with added value due to its potential use as an ingredient in the development of new products or as a substitute for conventional starch sources in industrial processes.

The functional properties of starches determine their potential applications in food systems. These properties depend largely on granular and molecular structure and can be physically, chemically or enzymatically modified. One way of modifying starch functional properties is by interaction with other food components, such as proteins. Starch-protein interactions are frequent in plant foods, particularly cereals and legumes, which are formed mainly of starches and proteins. An evaluation has been done of changes in the functional properties of three native starches (corn, Zea mays L.; cassava, Manihot esculenta; and lima bean, Phaseolus lunatus L.) when blended with lima bean protein concentrate. The gelatinization temperature of each blend increased compared to its corresponding native starch. The cassava starch/lima bean protein blend had the highest overall swelling power and water absorption capacity values at all temperatures. Maximum viscosity for each blend was higher than for the corresponding native starches. The blends of lima bean protein with cassava and corn starches did not exhibit syneresis. The lima bean starch/lima bean protein blend had the highest gel firmness values, followed by the blends with corn and cassava starches. The protein-starch mixtures are an alternative in the improvement of the starch functional properties which are useful in the development of nutritional products.

Las hojas de Stevia rebaudiana y sus glucósidos recientemente se han comenzado a utilizar de manera importante como edulcorantes. Sin embargo, existen reportes acerca del efecto antihiperglucemiante de extractos y un componente glucósido. El objetivo de este trabajo fue cuantificar los glucósidos de S. rebaudiana, evaluar la citotoxicidad y el efecto de la administración aguda y crónica del extracto sobre la glucemia en modelos animales como en humanos. Los glucósidos de los extracto de las variedades Morita II y Criolla se cuantificaron por HPLC, empleando una columna C18 (250 mm x 4.6 mm y tamaño de partícula de 5μm), con detector UV a 210 nm, fase móvil de acetonitrilo/amortiguador fosfato de sodio 10 mmol/L, pH 2.6 (32:68 v/v). Se realizó un estudio de citotoxicidad en células Vero, una prueba de tolerancia a la glucosa intraperitoneal y ensayo de consumo crónico (4 semanas) en un modelo animal de diabetes y finalmente, se determinó el índice glicémico (I.G) en individuos sanos. El contenido de glucósidos fue mayor en la variedad Morita II aunque la CC50 en ambas es >300 μg/mL. Las áreas bajo la curva de la IPGTT así como la glucosa en ayuno de los animales no fueron significativamente diferentes (p>0.05) y el I.G. del extracto fue 11.11%, lo cual lo clasifica como I.G. bajo. El extracto de S. rebaudiana Morita II es de bajo índice glicémico y, en las dosis evaluadas, no es citotóxico ni posee efecto agudo o crónico sobre la glucemia, lo cual lo hace un edulcorante inocuo.

Apis mellifera propolis has been used in ethnobotany and its compounds and therapeutic properties have been evaluated in various studies. Propolis from Maxcanú, Tizimín and Huhí, Yucatán, México were analyzed, determining the bioactive compounds (BC) of ethanolic extracts (PEE) and their potential use in the control of blood pressure, diabetes, and their antioxidant capacity. PEE was prepared by mixing 6 g of propolis with 20 mL of 95% ethanol, stirring daily for 28 days. BC were identified using HPLC and in vitro assays were performed on their antioxidant activity, ACE-I inhibition, and antidiabetic properties. Total phenols and flavonoids were between 1.27 ± 0.02 and 25.95 ± 0.99 mg GAE g−1 and 65.06 ± 3.48 and 85.64 ± 4.09 mg CE g−1 dry extract. The results of the in vitro assays were positive and a close relationship with the total content of flavonoids was detected, with epicatechin and p-coumaric being the main components identified. According to the results, the Huhí PEE had the highest values in all the assays, as well as the BC content. This study demonstrates that PEE can be used as a potential alternative in the treatment of certain diseases due to the therapeutic properties that exhibits.