Biodisponibilidad de minerales que lados y no que lados: una revisión sistemática / Bioavailability of chelated and non-chelated minerals: a systematic review

RESUMEN Los minerales son elementos esenciales para la vida y su equilibrio es imprescindible para múltiples procesos fisiológicos, bioquímicos y metabólicos. La forma en que son ingeridos determina su funcionalidad. Se sugiere que los minerales quelados tienen mejor biodisponibilidad. El objetivo del trabajo fue realizar una revisión sistemática para verificar si los minerales quelados (MQ) son más biodisponibles que los no quelados (MNQ). Se revisaron publicaciones en el período entre 2007 y 2017 en las bases de datos Pubmed, Lilacs y Cochrane Library en los idiomas portugués e inglés, y con las palabras clave: "mineral chelates", "micronutrient chelate", "bioavailability micronutrient chelate", organic mineral, "iron chelate", "zinc chelate", "magnesium chelate", "copper chelate" y "chelate" y sus respectivas traducciones en portugués (idioma original de este artículo). Se seleccionaron 446 artículos, quedando 24 trabajos pendientes de aplicación de criterios de inclusión/exclusión, siendo 15 de ellos en animales (manganeso, zinc, cobre, hierro, cromo, cobalto y selenio) y 9 en humanos, sólo con hierro y calcio. Los estudios demostraron mayor absorción, transporte y biodisponibilidad para los MQ en comparación con los MNQ. Sin embargo, serían necesarios más estudios en humanos, abordando la biodisponibilidad de otros minerales, así como la estandarización de las dosificaciones de estos micronutrientes.

ABSTRACT Minerals are essential elements for life and their balance is important for multiple physiological, biochemical and metabolic processes. The way they are ingested determines their functionality. It has been suggested that chelated minerals have better bioavailability. The objective of this work was to perform a systematic review of published articles to verify if chelated minerals are more bioavailable than non-chelated minerals. Publications were reviewed in the period between 2007 and 2017 in Pubmed, Lilacs and Cochrane Library databases in Portuguese and English with the keywords: "mineral chelates", "micronutrient chelate", "bioavailability micronutrient chelate", organic mineral, "iron chelate", "zinc chelate", "magnesium chelate", "copper chelate" and "chelate" and their respective translations in Portuguese (the original language of this article). 446 articles were selected and 24 papers were left after the application of inclusion / exclusion criteria. Of these, 15 were in animals (manganese, zinc, copper, iron, chromium, cobalt and selenium) and 9 in humans, and focused on iron and calcium. The studies showed greater absorption, transport and bioavailability for chelated compared to non-chelated minerals. More human studies, however, are necessary to address the bioavailability of other minerals, as well as the standardization of the dosajes of these micronutrients.

Níveis de cromo orgânico em rações para frangos de corte mantidos sob estresse por calor no período de um a 42 dias de idade / Levels of dietary chromiumin rations for male broilers kept under heat stress from one to 42 days of age

Avaliou-se o efeito da suplementação de cromo sobre o desempenho e o rendimento de cortes de frangos, mantidos em ambiente de alta temperatura, no período de um a 42 dias de idade. Foram utilizados 400 frangos de corte, machos, da linhagem Cobb, em um delineamento experimental inteiramente ao acaso, com cinco tratamentos, 0, 350, 700, 1.050 e 1.400ppb de cromo na ração, oito repetições e 10 aves por repetição. Nos períodos de um a 21 e de um a 42 dias de idade, não houve influência dos tratamentos sobre o ganho de peso, o consumo de ração e a conversão alimentar das aves, mas observou-se que o consumo de cromo aumentou de forma linear. Os tratamentos não influenciaram os pesos absoluto e relativo de nenhum dos cortes, peito, coxa e sobrecoxa, avaliados aos 42 dias de idade. A suplementação de até 1.400ppb de cromo na ração não influenciou o desempenho e o rendimento de cortes nobres de frangos de corte mantidos em estresse por calor, no período de um a 42 dias de idade.

The effect of dietary organic chromium supplementation on the performance and yield of prime cuts of male broilers from one to 42 days of age reared under high environmental temperature was evaluated. Four-hundred Cobb male broilers, averaging 38±0.14g were distributed in a simple sample random design with five treatments (0; 350; 700; 1,050; and 1,400ppb of chromium in ration), eight replicates, and ten birds per replicates. In periods from one to 21 and from one to 42 days of age, the treatments did not influence the weight gain, the food intake, and the feed:gain ratio of the birds. However, the chromium intake increased in a linear way. No effect of both absolute and relative weights of all evaluated cuts (breast, thigh, and drumstick) was observed. The dietary chromium supplementation up to 1,400ppb did not influence the performance and the carcass traits of the male broilers kept under heat stress from one to 42 days of age.