RESUMO
Asparagus production generates significant amounts of by-products during the summer and post-harvest growth period. By-products can be good sources of nutrients and phytochemicals. The interest in increasing the availability of proteins for human consumption has led to the use of new plant sources rich in proteins. The objective of this study was to use response surface methodology (RSM) to optimize the aqueous extraction process of proteins from asparagus leafy by-products, for the production of new protein ingredients. The optimum extraction condition was at pH 9, with 40 min of extraction at 50 °C, and the concentration was fixed at 5 g·L-1. The isolate obtained presented 90.48% protein with 43.47% protein yield. Amino acids such as alanine, proline, valine, leucine/isoleucine, asparagine, and phenylalanine were identified, and the antioxidant activity for 2,2 AZINO BIS (3-ethylbenzo thiazoline 6 sulfonic acid diammonium salt) was 145.76 equivalent to Trolox µmol.100g-1 and for DPPH 65.21 equivalent to Trolox µmol.100g-1. The product presented favorable technological properties (water absorption capacity 4.49 g·g-1 and oil absorption capacity 3.47 g·g-1) and the color tended towards dark green (L* 31.91, a* -1.01, b* -2.11). The protein isolate obtained through the extraction optimization process showed high potential to be used as a protein ingredient.
RESUMO
Genetic variation among sweet, purple, and yellow passion fruit accessions was assessed using inter-simple sequence repeat (ISSR) markers. Eighteen ISSR primers were used to evaluate 45 accessions. The number of polymorphic bands per primer varied from 4 to 22, with 12.4 bands per primer on average. Nei's genetic distance between accessions ranged from 0.04 to 0.35. Clustering using the neighbor-joining method resulted in the formation of 11 major clusters. It was not possible to classify the accessions according to their geographic origin, showing that there is no structure in the gene bank. The overall mean Shannon-Weaver diversity index was 0.32, indicating good resolution of genetic diversity in passion fruit germplasm using ISSR markers. Our results indicate that ISSR can be useful for genetic diversity studies, to provide practical information for parental selection and to assist breeding and conservation strategies.