Antioxidant Activity of Foods and Natural Products.

Today, there is growing recognition of the importance of antioxidants in promoting human health and well-being [...].

The Chemical Characterisation of the Maritime Pine Bark Cultivated in Northern Portugal.

Maritime pine, scientifically known as Pinus pinaster, holds a vital role in Iberian Peninsula forests, primarily as a source of wood for panels, paper, and cellulose production. Recently, there has been a growing interest in utilising agroforestry by-products to yield valuable chemicals for applications in various sectors, including the food, pharmaceutical, and bioenergy industries. This study aimed to assess the value of the primary by-product of Pinus pinaster from the Minho region of northwestern Portugal, i.e., the bark. The research extensively examined the bark's chemical and thermal characteristics, including ash content, extractives, lignin, cellulose, hemicellulose, fatty acids, and mineral composition. Additionally, various analytical techniques like FTIR, SEM, DSC, DTG, and XRD were used to observe chemical structure differences. The results reveal that the Pinus pinaster bark primarily consists of lignin (51.15%) and holocellulose (46.09%), with extractives mainly soluble in toluene-ethanol, followed by water, and a small amount of them are soluble in ethanol. The bark contained around 0.44% ash, and heavy metals such as Cd and Pb were not found. During degradation, Pinus pinaster experienced a 10% mass loss at 140 °C. In terms of crystallinity, holocellulose and cellulose showed similar percentages at approximately 25.5%, while α-cellulose displayed the highest crystallinity index at 41%.

Chemical composition and biological activities of whole and dehulled hemp (Cannabis sativa L.) seeds.

This study aimed to determine a complete chemical composition of eight different varieties of whole hemp seeds and eight samples of commercial dehulled hemp seeds. We also evaluated the phenolic profiles and antioxidant, cytotoxic, and antimicrobial properties of hydromethanolic seed extracts. Whole hemp seeds contain much more fibre than dehulled hemp seeds, which contain more fat and protein. Sucrose and raffinose were the most abundant soluble sugars, and citric and oxalic acids were the most abundant organic acids. In the hydromethanolic hemp seed extracts, we detected the phenolic acids ferulic acid-hexoside and syringic acid. Whole hemp seed extracts exhibited better antioxidant activity than dehulled hemp seed extracts, especially in the TBARS assay. Cytotoxic activity against NCI-H460 cells was also observed. The dehulled hemp seed extracts displayed antibacterial activity, especially against Bacillus cereus, Listeria monocytogenes, and Enterococcus faecalis, and antifungal activity to a lesser extent.