RESUMO
Among the most important agro-industrial activities in the Mediterranean basin, olive oil production has a high impact on the economy of many Mediterranean countries. However, olive oil extraction generates huge quantities of byproducts, including leaves, pomace residues, stones and wastewater, which have severe environmental impacts mainly because of their phytotoxicity and great organic content. Olive oil byproducts are regarded as inexpensive and abundant raw materials rich in bioactive compounds with high and varied health-related activities. Several phenolic compounds and terpenoids were recovered from olive byproducts using different conventional and advanced extraction methods due to their potential to be used in food, packaging, pharmaceutical, and cosmetic industries. Recently, the use of olive byproducts and their functional compounds to enhance the functional properties of packaging systems was investigated as a sustainable strategy for food preservation, fostering the sustainability of the olive-oil chain, and promoting circular economy. In this framework, the main goals of this review are to summarize the main bioactive compounds in olive byproducts, to review the main advancements in their extraction, purification, and characterization, and finally to discuss their applications in food packaging systems as well as safety-related aspects.
Assuntos
Olea , Embalagem de Alimentos , Olea/química , Azeite de Oliva/análise , Azeite de Oliva/química , Fenóis/análise , Folhas de Planta/químicaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Masson Pine pollen (Pinus massoniana; MP) are used in Traditional Chinese Medicine to treat gut conditions. Early in vivo work supports this claim and suggests interaction of the material with the gastrointestinal immune system. AIM OF THE STUDY: The present study tested if and how MP material activates HD11 chicken macrophages in vitro using material from different production sites and harvest years. MATERIAL & METHODS: We applied twelve batches of MP from different Chinese production sites and harvest years. Materials were subjected to LAL tests (endotoxic activity), GC-MS (fatty acid analysis), and plate techniques (microbiological background, antimicrobial activity). Furthermore, HD11 chicken macrophages were challenged (6 h, 37 °C) with MP or LPS (E. coli O111:B4), respectively, to quantify nitric oxide (NO) production and immune gene expression (RT-qPCR). RESULTS: MP material promoted strong signals in LAL tests and contained significant amounts of 3-hydroxydodecanoic acid and 3-hydroxymyristic acid, irrespective of processing, harvest year, or origin. The pollen material activated HD11 chicken macrophages, which was confirmed by spikes of NO release and k-means cluster analysis of TLR-signaling pathway gene expression data. Response of NO production to Log2-titration of MP and LPS-treated media was in any case linear and significant. The response was reduced by polymyxin-B (PMB) and the inhibition was twice as strong for LPS than MP. No or minor microbiological background was detected on the majority of MP samples. Three samples showed presence of spoilage microorganisms and Gram-negative bacteria, but this did not correlate to LAL data or bacterial DNA counts. No antimicrobial activity of MP was evident. CONCLUSION: Pollen of the Masson Pine activated HD11 chicken macrophages in vitro, which is likely partially due to a background of bacterial LPS associated with the pollen material. However, as most of the effect (appr. 80%) could not be blocked by PMB this is certainly due to other stimuli. We hypothesize that polysaccharides and oligosaccharides of the pollen matrix have the potential to interact with certain immune receptors presented on the plasma membrane of chicken macrophages.