Quality of bee pollen submitted to drying, pasteurization, and high-pressure processing - A comparative approach.

Bee Pollen is a valuable and useful natural food product that can be used for different purposes, among which medical ones. This matrix is deemed a superfood because of its chemical composition, which is rich in nutrients and possesses significant bioactivities, including antioxidant and microbiological properties. Nevertheless, the storage conditions and processing methods must be optimized to maintain their properties and maximise their application. This work investigates the best bee pollen conservation process and its impact on individual constituents. Monofloral bee pollen was analysed for 30 and 60 days after three different storage processes (drying, pasteurization, and high-pressure pasteurization). The results showed a decrease mainly in fatty acid and amino acid content for the dried samples. The best results were obtained with high-pressure pasteurization, maintaining the proteins, amino acids and lipids characteristics of pollen and the lowest microbial contamination.

Post-Transcriptional Gene Silencing of Glucanase Inhibitor Protein in Phytophthora cinnamomi.

Ink disease is considered one of the most significant causes contributing to the decline of chestnut orchards. The reduced yield of Castanea sativa Mill can be attributed to two main species: Phytophthora cinnamomi and Phytophthora cambivora, with the first being the main pathogen responsible for ink disease in Portugal. P. cinnamomi is a highly aggressive and widely distributed plant pathogen, capable of infecting nearly 1000 host species. This oomycete causes substantial economic losses and is accountable for the decline of numerous plant species in Europe and worldwide. To date, no effective treatments are available to combat these pathogens. Given chestnut's economic and ecological significance, particularly in Portugal, it is crucial to investigate the molecular mechanisms underlying the interaction between Phytophthora species and host plants. This can be achieved through the study of the glucanase inhibitor protein (GIP) produced by P. cinnamomi during infection. The technique of RNA interference (RNAi) was employed to suppress the GIP gene of P. cinnamomi. The resulting transformants, carrying the silenced gene, were used to infect C. sativa, allowing for the assessment of the effects of gene silencing on the plant's phenotype. Additionally, bioinformatics tools predicted the secretion of GIP protein. The obtained results validate RNAi as a potential alternative tool for studying molecular factors and for controlling and managing P. cinnamomi.

Melipona scutellaris Geopropolis: Chemical Composition and Bioactivity.

Geopropolis has been used in traditional medicine for centuries. In this study, the botanical origin, physicochemical profile, and biological activities of geopropolis from Melipona scutellaris harvested during rainy and dry seasons were investigated. Palynological analysis identified over 50 pollen types, with Schinus terebinthifolius and Cecropia being the predominant types. The analytical results were in line with those reported in the literature. Rainy-season geopropolis exhibited higher total phenol and flavonoid content (determined using High Performance Liquid Chromatography-25.13% and 3.92%, respectively) compared to the dry season (19.30% and 2.09%); the major peaks (naringin, gallic acid, and catechin) were similar among samples. Antioxidant capacity was assessed via DPPH, reducing power, and ß-carotene/linoleic acid discoloration assays. Rainy-season samples displayed superior antioxidant activity across methods. Antimicrobial effects were determined using microdilution, while the impact on the cholinesterase enzyme was quantified using 5-thio-2-nitrobenzoic acid accumulation. Anti-inflammatory and antimutagenic activities were assessed through hyaluronidase enzyme inhibition and by utilizing Saccharomyces cerevisiae ATCC-20113 cells. Both samples exhibited anti-inflammatory and antimutagenic properties. Moreover, a significant inhibition of acetylcholinesterase was observed, with IC50 values of 0.35 µg/mL during the rainy season and 0.28 µg/mL during the dry season. Additionally, the geopropolis displayed antimicrobial activity, particularly against Staphylococcus aureus. These findings suggest the therapeutic potential of M. scutellaris geopropolis in the context of inflammatory, oxidative, and infectious diseases.