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Provitamin A carotenoids in grain reduce aflatoxin contamination of maize while combating vitamin A deficiency

natalia palacios rojas Jose Crossa (2019)

Aflatoxin contamination of maize grain and products causes serious health problems for consumers worldwide, and especially in low- and middle-income countries where monitoring and safety standards are inconsistently implemented. Vitamin A deficiency (VAD) also compromises the health of millions of maize consumers in several regions of the world including large parts of sub-Saharan Africa. We investigated whether provitamin A (proVA) enriched maize can simultaneously contribute to alleviate both of these health concerns. We studied aflatoxin accumulation in grain of 120 maize hybrids formed by crossing 3 Aspergillus flavus resistant and three susceptible lines with 20 orange maize lines with low to high carotenoids concentrations. The hybrids were grown in replicated, artificially-inoculated field trials at five environments. Grain of hybrids with larger concentrations of beta-carotene (BC), beta-cryptoxanthin (BCX) and total proVA had significantly less aflatoxin contamination than hybrids with lower carotenoids concentrations. Aflatoxin contamination had negative genetic correlation with BCX (-0.28, p < 0.01), BC (-0.18, p < 0.05), and proVA (-0.23, p < 0.05). The relative ease of breeding for increased proVA carotenoid concentrations as compared to breeding for aflatoxin resistance in maize suggests using the former as a component of strategies to combat aflatoxin contamination problems for maize. Our findings indicate that proVA enriched maize can be particularly beneficial where the health burdens of exposure to aflatoxin and prevalence of VAD converge with high rates of maize consumption.

Article

Beta-Carotene Beta-Cryptoxanthin Biofortification Maize Breeding CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AFLATOXINS MAIZE MYCOTOXINS VITAMIN A DEFICIENCY CAROTENOIDS AGRICULTURAL SCIENCES AND BIOTECHNOLOGY MYCOTOXINS VITAMIN A DEFICIENCY AFLATOXIN

Functional polymorphism for crtRB1 gene loci in tropical maize (Zea mays L.) inbred lines

Pervez Zaidi Prakash Kuchanur (2017)

Maize (Zea mays L.) is an important cropknown for its carotenoid diversity amongcereals which accumulates significant levels of proA (provitamin A) and non-proA carotenoids itskernels. The proA components of maize endosperm promises to solve themajor global problem VAD(Vitamin A deficiency). Among several genes involved in-carotene biosynthetic pathway, crtRB1isvery important gene associated with three polymorphismsviz., 5 'TE, In Del4 and 3'TE (TransposableElement) responsible for variation in carotenoid levels in maize endosperm. Due to insertion of TE at 3'UTR (Un Translated Region), crtRB1again exhibits polymorphism with 3 alleles, however, only allele1(favourable allele; 543bp amplicon) of this crtRB1-3'TE gene will double the-carotene concentrationin maize endosperm and allele 2 and 3 termed as unfavourable. This study was undertaken to find outthe allelic difference for crtRB1gene loci. Totally 228 tropical maize inbred lines were screened for allele1of crtRB1gene using crtRB1-3’TE gene specific markers. Among 228 in breds, 226 inbreds showed thepresence of allele 2 and the two inbredsVL1016247 and VL1016213 possessed both alleles 1 and 2 whichare found to be heterozygous for crtRB1 loci. This study indicated the possible use of (VL1016247 andVL1016213) these two inbreds for developing provitaminA (proA) rich maize hybrids using markerassisted selection (MAS).

Article

Zea mays Inbred lines Polymorphism Tropical Maize Provitamin A β-carotene crtRB1 AGRICULTURAL SCIENCES AND BIOTECHNOLOGY CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

β-Carotene Production under Greenhouse Conditions

RODRIGO CASTAÑEDA MIRANDA LUIS OCTAVIO SOLIS SANCHEZ (2009)

β-carotene is a secondary metabolite that is a hydrocarbon carotene predominantly

located in lower concentrations in PS II functioning as a helper to harvest light pigment

during photosynthesis and to dissipate excess energy before damage occurs. As other

carotenes, β-carotene is uniquely synthesized in plants, algae, fungi and bacteria. βcarotene is the main diet precursor of pro-vitamin A. Additionally, β-carotene serves as

an essential nutrient and is in high demand in the market as a natural food colouring

agent, as an additive to cosmetics and also as a health food. Several approaches have

been carried out in order to increase β-carotene production in algae, bacteria, fungi and

plants using biotechnological and engineering focuses. In the case of plants, such species

as the tomato have important β-carotene contents, which are theoretically amenable to

management using approaches such as fertilization, growth conditions and mild stress.

On the other hand, greenhouse structures can protect crops from wind and rain, and can

also protect from insects when fitted with insect exclusion screens. β-carotene production

could potentially be improved and enhanced in greenhouse conditions in plants as well as in algae, based on the exclusion of the structure, and the possibility of controlling aspects

such as climate, fertilization and stress management, among others. Production of βcarotene (and other secondary metabolites) from several organisms in greenhouse

conditions should be an interesting future approach, visualizing the greenhouse as a

“factory” in frontier technologies such as biotechnology and mechatronics in order to

optimize this production.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Book part

BIOLOGÍA Y QUÍMICA β-carotene photosynthesis plants

Impact of Silicon Nanoparticles on the Antioxidant Compounds of Tomato Fruits Stressed by Arsenic

MAGIN GONZALEZ MOSCOSO NADIA VALENTINA MARTINEZ VILLEGAS Gregorio Cadenas Pliego Adalberto Benavides Mendoza MARIA DEL CARMEN RIVERA CRUZ SUSANA GONZALEZ MORALES ANTONIO JUAREZ MALDONADO (2019)

"Tomato fruit is rich in antioxidant compounds such as lycopene and β-carotene. The beneficial effects of the bioactive compounds of tomato fruit have been documented as anticancer activities. The objective of this research was to determine whether arsenic (As) causes changes in the content of antioxidant compounds in tomato fruits and whether Silicon nanoparticles (SiO2 NPs) positively influence them. The effects on fruit quality and non-enzymatic antioxidant compounds were determined. The results showed that As decreased the oxide-reduction potential (ORP), while lycopene and β-carotene were increased by exposure to As at a low dose (0.2 mg L−1), and proteins and vitamin C decreased due to high doses of As in the interaction with SiO2 NPs. A dose of 250 mg L−1 of SiO2 NPs increased glutathione and hydrogen peroxide (H2O2), and phenols decreased with low doses of As and when they interacted with the NPs. As for the flavonoids, they increased with exposure to As and SiO2 NPs. The total antioxidant capacity, determined by the ABTS (2,2´-azino-bis[3-ethylbenzthiazolin-6-sulfonic acid]) test, showed an increase with the highest dose of As in the interaction with SiO2 NPs. The application of As at low doses induced a greater accumulation of bioactive compounds in tomato fruit; however, these compounds decreased in high doses as well as via interaction with SiO2 NPs, indicating that there was an oxidative burst."

Article

Bioactive compounds Oxidative stress Lycopene Hydrogen peroxide β-carotene INGENIERÍA Y TECNOLOGÍA INGENIERÍA Y TECNOLOGÍA

Ecología de comunidades de macromicetos a lo largo de un gradiente altitudinal en Santa Catarina Ixtepeji, Oaxaca

Sadoth Vázquez Mendoza (2008)

Los macromicetos son uno de los grupos de organismos mas diversos, sin embargo su estudio tanto a nivel taxonómico como ecológico esta poco desarrollado, en especial en los trópicos. Por ello, en este trabajo se estimó la riqueza específica de macromicetos en el municipio de Santa Catarina Ixtepeji, Oaxaca; y analizó patrones de diversidad y productividad con respecto a la altitud. El trabajo de campo se realizó en cuatro localidades en un intervalo de 2100 a 3120 m, en parcelas de 7m2 cada 5 m a lo largo de 5 transectos de 125 m de longitud. Se recolectaron 1762 especimenes distribuidos en 669 especies y morfoespecies. Se encontró una relación positiva entre la riqueza específica y la productividad con la altitud. Esta relación fue encontrada para todos los grupos ecológicos de macromicetos con excepción de los hongos lignícolas los cuales tuvieron su mayor diversidad y productividad a los 2245 m. Los hongos lignícolas tuvieron en todos los sitios la mayor proporción de biomasa, mientras que en los sitios de mayor altitud fueron más abundantes los micorrícicos. La humedad del suelo también presenta relación positiva con la altitud y esta relacionada de igual forma con la riqueza especifica y la productividad de macromicetos. La similitud entre sitios, analizada mediante el índice de Sorensen y el de Renkonnen, fue baja por lo que la diversidad beta fue muy alta. Los resultados obtenidos sugieren la necesidad de modificar las medidas de selección de áreas naturales protegidas, ampliando la protección de zonas de media y alta montaña, en especial por los cambios provocados por el calentamiento global.

Master thesis

BIOLOGÍA Y QUÍMICA Macromicetos altitud productividad fúngica patrones ecológicos diversidad beta

Características químicas y sensoriales de la carne de cerdo, en función del consumo de dietas con ractopamina y diferentes concentraciones de lisina

MARIA ANTONIA MARIEZCURRENA BERASAIN DIEGO BRAÑA VARELA MARIA DOLORES MARIEZCURRENA BERASAIN IGNACIO ARTURO DOMINGUEZ VARA RUBEN DANILO MENDEZ MEDINA MARIA SALUD RUBIO LOZANO (2012)

Se evaluaron las características químicas y sensoriales de la carne de cerdos alimentados con Ractopamina (RAC) a 5 ppm (Paylean®, Elanco, México) y diferentes concentraciones de lisina digestible ileal estandarizada (lys-dig), en dietas con 3.3 Mcal EM/ kg y 14.5 % de proteína cruda, lo que representa un contenido de proteína de 10 % inferior al mínimo recomendado por el laboratorio y la literatura. Se utilizaron 48 cerdos (peso corporal inicial 77.2±3.42 y final 110.0±3.0 kg) que fueron asignados a uno de cuatro tratamientos: C) Dieta de finalización Control (lys-dig 0.65%); RAL) alta en Lisina con RAC (lys-dig 1%); RNL) Niveles normales de lisina con RAC (lis-dig 0.80%); RBL) Baja en lisina con RAC (lis-dig 0.50%). Después de 28 días en sus respectivas dietas, los animales se sacrificaron y procesaron. De cada animal, se recolectaron cuatro chuletas (2.5 cm de grosor) y se determinó grasa intramuscular y evaluación sensorial. Los resultados indican que con la adición de RAC, en dietas con 14.5 % de proteína, se aumenta (P<0.01) la grasa intramuscular en 25 %. Un incremento mayor (hasta el 50 %) en grasa intramuscular se obtuvo con dietas con RAC y una baja concentración de lisina (0.5% lys-dig). El panel de consumidores no detectó diferencias en aroma, sabor y textura (P>0.17), pero sí detectó una mayor jugosidad de carne de cerdo (P<0.02) de animales que consumieron la dieta RBL. Es factible mejorar la calidad de la carne de cerdo mediante el uso de RAC y dietas bajas en proteína y lisina.

Article

Veterinaria Carne de cerdo Beta adrenérgico Composición química Análisis sensorial BIOLOGÍA Y QUÍMICA