Structural polysaccharides and dietary fiber in floral buds (tunitas) of Nopalea cochenillifera (L.) Salm-Dick from different growth stages [Polisacáridos estructurales y fibra dietética en brotes florales (tunitas) de Nopalea cochenillifera (L.) Salm-Dick de diferente estadio de desarrollo] Article uri icon

abstract

  • In Mexico, the young cladodes (nopalitos) and floral buds (tunitas) of Nopalea cochenillifera are consumed as vegetables, but there is no information on the content of structural polysaccharides and dietary fiber in floral buds. The objective of this study was to extract, purify and quantify the structural polysaccharides (mucilages, pectins, loosely and tightly hemicelluloses bound to cellulose, and cellulose) and dietary fiber (soluble, insoluble and total) in floral buds of N. cochenillifera in four stages of development. The hypothesis was that soluble structural polysaccharides increase during the development of floral buds. Floral buds were harvested between 06:00 and 09:00 h in the municipality of San Ciro de Acosta, San Luis Potosí, Mexico; they were classified by their length and development in four stages (GS); thorns were eliminated, lyophilized and crushed. The structural polysaccharides were extracted in sequence with aqueous solvents (water, ammonium oxalate and potassium hydroxide). Soluble dietary fiber was determined as the sum of mucilage, pectin and loosely bound hemicelluloses, and insoluble as the sum of tightly bound hemicelluloses and cellulose. Total dietary fiber was the sum of all structural polysaccharides. The experimental design was completely randomized with four replications per treatment. The content of mucilage and loosely bound hemicelluloses varied between GS, from 5.6 to 9.8 %25 and from 3.1 to 15.0 %25. Pectins, tightly bound hemicelluloses and cellulose remained stable during the development of floral buds (6.4, 12.4 and 12.7 %25). The GS2 had the highest dietary fiber content (46.3 %25). The content of mucilages, loosely bound hemicelluloses and total and soluble dietary fiber increased in floral buds of N. cochenillifera in GS2, followed by their decrease in GS3 and GS4. © 2019, Colegio de Postgraduados.

publication date

  • 2019-01-01