Edith Oliva Cuevas-Rodríguez

Solid-state bioconversion of chickpea (Cicer arietinum L.) by Rhizopus oligosporus to improve total phenolic content, antioxidant activity and hypoglycemic functionality.

Abstract The objective of this investigation was to study the effect of time during solid state bioconversion (SSB) on total phenolic content (TPC), antioxidant activity (AoxA), and inhibitory properties against α-amylase and α-glucosidase of chickpea. Chickpea cotyledons were inoculated with a suspension of Rhizopus oligosporus and incubated at 35 °C for 24, 36, 48, 60, 72, 84, 96 and 108 h. The best time to produce bioprocessed chickpea (added with seed coats) flour with the highest AoxA was 108 h. SSB substantially increased TPC and AoxA of chickpea extracts in 2.78 and 1.80–1.94 times, respectively. At 36 and 96 h of fermentation, the SSB process improved in vitro α-amylase and α-glucosidase inhibition (AI and GI indexes) activities of chickpea extracts in 83 and 370%, respectively. SSB is a good strategy to enhance health-linked functionality of chickpea, due to improved TPC, AoxA and content of strong natural inhibitors of enzymes associated with diabetes.

Nixtamalized Instant Flour from Corn (Zea mays L.) Meal: Optimization of Nixtamalization Conditions

ABSTRACT The present investigation provides a new method for the nixtamalization process wherein corn endosperm fractions (corn meal) are treated in an alkaline solution that yields quality masa or instant masa flour like traditional nixtamalization process (alkaline cooking of corn with lime). The objective of this work was to determine the best combination of nixtamalization process variables for producing nixtamalized instant flour (NIF) from corn meal. Nixtamalization conditions were selected from factorial combinations of process variables including nixtamalization time (NT 8–22 min) and cooking temperature (CT 78–88°C). A central composite rotable experimental design was chosen. Lime concentration was 1% (10 g of Ca(OH)2/L of water) and ratio of corn meal to cooking medium was 1:4. At the end of each cooking, each treatment was steeped for 5 hr at room temperature (25°C). Nixtamalized corn meal was dried (55°C/12 hr) and milled to pass through 80 U.S. mesh to obtain NIF. Response surface methodology...

Enhancement of nutritional properties, and antioxidant and antihypertensive potential of black common bean seeds by optimizing the solid state bioconversion process

Abstract The aim of this work was to obtain a functional flour with enhanced nutritional properties, and antioxidant and antihypertensive potential from black bean seeds by optimizing the solid state bioconversion (SSB) process using a Rhizopus oligoporus strain. Response surface methodology was applied as optimization technique. A central composite experimental design with two factors [fermentation temperature (FT) = 30–40 °C/fermentation time (Ft) = 6–108 h] and five levels was used (13 treatments). The bioprocessed cotyledons from each treatment were dried, milled, and blended with its previously dried-milled seed coats. The best combination FT/Ft of SSB to obtain the functional flour was 38 °C/100 h. SSB increased the calculated protein efficiency ratio (from 1.59 to 2.40), antioxidant activity (from 13 948 to 22 733 µmol ET/100 g, dw), total phenolic compounds (TPC) (from 190 to 432 mg EGA/100 g, dw) and antihypertensive potential (IC50 from 95.57 to 0.0321 µg/mL). SSB is an effective strategy to improve the TPC of common beans for enhanced functionality.

Physical, Compositional, and Wet-Milling Characteristics of Mexican Blue Maize (Zea mays L.) Landrace

Mexico has the largest diversity of genetic resources for maize in the world, with about 59 different landraces. However, little is known about their wet-milling characteristics. The aim of this study was to determine whether 15 Mexican blue maize (Zea mays L.) genotypes of Elotero de Sinaloa landrace collected in the northwestern region of Mexico have suitable wet-milling properties. Great variability of physical, compositional, and wet-milling characteristics among these blue maize genotypes was observed. The FAUAS-457 and FAUAS-488 maize genotypes had similar starch yield and starch recovery as reported for the wet-milling industry, which indicated that they may be useful as a source of extractable starch. Residual protein levels in the starch fractions were in the range of 0.39–0.68%, and total solids recovery exhibited a mean value of 98.8%, indicating acceptable efficacy of the wet-milling process. This process afforded starches from blue maize genotypes with low protein contents. Wet-milling fracti...

Phenolic Acids Profiles and Cellular Antioxidant Activity in Tortillas Produced from Mexican Maize Landrace Processed by Nixtamalization and Lime Extrusion Cooking

Phenolic acids profiles, chemical antioxidant activities (ABTS and ORAC), as well as cellular antioxidant activity (CAA) of tortilla of Mexican native maize landraces elaborated from nixtamalization and lime cooking extrusion processes were studied. Both cooking procedures decreased total phenolics, chemicals antioxidant activity when compared to raw grains. Extruded tortillas retained 79.6–83.5%, 74.1–77.6% and 79.8–80.5% of total phenolics, ABTS and ORAC values, respectively, compared to 47.8–49.8%, 41.3–42.3% and 43.7–44.4% assayed in traditional tortillas, respectively. Approximately 72.5–88.2% of ferulic acid in raw grains and their tortillas were in the bound form. Regarding of the CAA initially found in raw grains, the retained percentage for traditional and extruded tortillas ranged from 47.4 to 48.7% and 72.8 to 77.5%, respectively. These results suggest that Mexican maize landrace used in this study could be considered for the elaboration of nixtamalized and extruded food products with nutraceutical potential.

Amaranth Protein Hydrolysates Efficiently Reduce Systolic Blood Pressure in Spontaneously Hypertensive Rats

Alcalase is the enzyme of choice to release antihypertensive peptides from amaranth proteins, but the hydrolysis conditions have not been optimized yet. Furthermore, in vivo assays are needed to confirm such a hypotensive effect. Our aim was to optimize the hydrolysis of amaranth protein with alcalase and to test in vivo the hypotensive effect of the hydrolysates. A response surface analysis was carried out to optimize the hydrolysis reaction. The response variable was the Angiotensin Converting Enzyme (ACE-I) inhibition. The hydrolysis degree was determined (free alpha-amino groups measurement). The optimized hydrolysate bioavailability was assessed in the sera of mice and the hypotensive effect was assessed in spontaneously hypertensive rats. Control groups were administered captopril or water. The optimized hydrolysis conditions were: pH = 7.01, temperature = 52 °C, enzyme concentration 0.04 mU/mg, and time = 6.16 h. The optimized hydrolysate showed a 93.5% of ACE-I inhibition and a hydrolysis degree of 74.77%. After supplementation, the hydrolysate was bioavailable in mice from 5 to 60 min, and the hypotensive effect started at 4 h in spontaneously hypertensive rats (p < 0.05 vs. water group). This effect was similar to the captopril hypotensive effect for the next 3 h (p > 0.05). The use of amaranth-optimized hydrolysates as hypotensive supplements or ingredient for functional foods seems feasible.