Distribution of bioactive compounds in maize fractions obtained in two different types of large scale milling processes

Maize kernels contain different bioactive compounds that are important for human health. The aim of this study was to analyze the distribution of the bioactive compounds in maize fractions derived from two industrial dry-milling processes, characterized by a dry-degermination (DD) system and a tempering-degermination (TD) system.The bioactive compounds in maize resulted unevenly distributed in the milling fractions of the kernel. By-products such as the germ and the animal feed flour, had higher total antioxidant capacity (TAC), total polyphenol content (TPC) and total dietary fibre content (TDF) than the whole grains, while xanthophyll and resistant starch resulted to be higher in the fractions derived from the vitreous endosperm. The germ fraction showed also the highest folate content. Results also showed that the type of degermination process influences the bioactive compound contents in the milling fraction, in accordance to the effectiveness of the germ and bran removal from the endosperm fractions. In particular, the animal feed flour obtained by means of TD system resulted in a higher TAC, TPC and TDF than the same fraction obtained by means of the DD system. Conversely, the extraction rate do not affect the recovery of bioactive components in particular fractions.     

ISSR molecular characterization and leaf volatiles analysis of Pittosporum undulatum Vent. naturalized in the Azores archipelago (Portugal)

Pittosporum undulatum from the Azores archipelago was characterized by both molecular and volatiles analyses. Inter simple sequence repeat (ISSR) evaluation was performed based on a random sampling of 77 individuals from a total of 123 samples collected on all the Azorean islands. Molecular studies grouped the samples mainly according to the geographical collection site, with some exceptions. Leaf volatiles were isolated by distillation-extraction and analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) from all the 123 samples. Cluster analysis based on the leaf volatiles chemical composition defined three main clusters, not related to sample site collection, and was based mainly on the relative amounts of limonene (3-89%), sabinene (0.1-64%) and terpinen-4-ol (traces-43%). Clusters obtained from both molecular studies and volatiles composition were not superimposable and no correlation between ISSR markers and volatile oils could be drawn. The results suggest that there is a high genetic variability among individuals of P. undulatum that can explain the invasive ability of this species in the Azores archipelago. The detailed characterization of this alien weed species may assist finding potential commercial uses as well as management strategies to help its eradication and/or control.