Metabolite characterization of fifteen by-products of the coffee production chain: From farm to factory.

Approximately 11.4 million tonnes of solid by-products and an increased amount of waste water will be generated during the 2020/21 coffee harvest. There are currently no truly value-adding uses for these potentially environmentally threatening species. This work presents the most wide-ranging chemical investigation of coffee by-products collected from farms to factories, including eight never previously investigated. Twenty compounds were found for the first time in coffee by-products including the bioactive neomangiferin, kaempferol-3-O-rutinoside, lup-20(29)-en-3-one and 3,4-dimethoxy cinnamic acid. Five by-products generated inside a factory showed caffeine (53.0-17.0 mg.g-1) and/or chlorogenic acid (72.9-10.1 mg.g-1) content comparable to coffee beans, while mature leaf from plant pruning presented not only high contents of both compounds (16.4 and 38.9 mg.g-1, respectively), but also of mangiferin (19.4 mg.g-1) besides a variety of flavonoids. Such by-products are a source of a range of bioactive compounds and could be explored with potential economic and certainly environmental benefits.

Functionalization of sweet potato leaf polyphenols by nanostructured composite ß-lactoglobulin particles from molecular level complexations: A review.

Sweet potato leaf polyphenols (SPLPs) have shown potential health benefits in the food and pharmaceutical industries. Nowadays, consumption of SPLPs from animal feeds to foodstuff is becoming a trend worldwide. However, the application of SPLPs is limited by their low bioavailability and stability. ß-lactoglobulin (ßlg), a highly regarded whey protein, can interact with SPLPs at the molecular level to form reversible or irreversible nanocomplexes (NCs). Consequently, the functional properties and final quality of SPLPs are directly modified. In this review, the composition and structure of SPLPs and ßlg, as well as methods of molecular complexation and mechanisms of formation of SPLPsßlgNCs, are revisited. The modified functionalities of SPLPsßlgNCs, especially protein conformational structures, antioxidant activity, solubility, thermal stability, emulsifying, and gelling properties including allergenic potential, digestibility, and practical applications are discussed for SPLPs future development.

Burdock (Arctium lappa L) roots as a source of inulin-type fructans and other bioactive compounds: Current knowledge and future perspectives for food and non-food applications.

The roots and tubers of the Asteraceae family are known as a source of various oligosaccharides, and chicory roots and Jerusalem artichoke have stood out for its commercial viability. However burdock root (Arctium lappa L.), which is adapted to temperate climate, moist, and sandy soil, is still unknown as health food in the western world. This review showed the potential of burdock roots as a source of prebiotic fibers, chlorogenic acids, cinnarine, lignans, and quercetin. The extraction methods of burdock functional compounds are made with water, temperature and time variations only. Biological assays showed antioxidant activity, anti-inflammatory, and hypolipidemic properties, and gastric mucosal defense mechanisms, among others. Therefore, the use of burdock roots as functional food should be encouraged in countries that have imported products derived from other roots of the same family for health benefits.

Valorisation of kitul, an overlooked food plant: Phenolic profiling of fruits and inflorescences and assessment of their effects on diabetes-related targets.

Caryota urens L. has long been valued as a traditional food, the edible fruits being eaten raw and the inflorescences commonly used on sweet sap and flour production. In the current work, the phenolic profile of methanol extracts obtained from the inflorescences and fruits was unveiled for the first time, nine caffeic acid derivatives being identified and quantified. Since kitul products have been reported for their antidiabetic properties, extracts radical scavenging activity and α-amylase, α-glucosidase and aldose reductase inhibitory activity were assessed. The inflorescences' extract was particularly active against yeast α-glucosidase (IC50 = 1.53 µg/mL), acting through a non-competitive inhibitory mechanism. This activity was also observed in enzyme-enriched homogenates obtained from human Caco-2 cells (IC50 = 64.75 µg/mL). Additionally, the extract obtained from the inflorescences showed no cytotoxicity on HepG2, AGS and Caco-2 cell lines. Our data suggest that C. urens inflorescences can support the development of new functional foods with α-glucosidase inhibitory activity.

Activation of caspase-3 in gastric adenocarcinoma AGS cells by Xylopia aethiopica (Dunal) A. Rich. fruit and characterization of its phenolic fingerprint by HPLC-DAD-ESI(Ion Trap)-MSn and UPLC-ESI-QTOF-MS2.

While the fruits of Xylopia aethiopica (Dunal) A. Rich. are important in African countries as a local trade product, their composition remains scarcely investigated. Phenolic fingerprint is herein delivered through HPLC-DAD-ESI(Ion Trap)-MSn and UPLC-ESI-QTOF-MS2 analysis, six cinnamoylquinic acid derivatives and twenty-four flavonoid glycosides being determined, chrysoeriol-7-O-glycosides being the main constituents. A cytotoxicity screening of twenty-eight hydroethanol extracts, obtained from a collection of Guinea-Bissauan plants, against A549 and AGS carcinoma cells, revealed the selective and potent effect towards AGS cells (IC50 = 151 × 10-3 g L-1), upon exposure to the extract from X. aethiopica fruits. Additional experiments demonstrated insignificant effect on LDH release at 151 × 10-3 g L-1, morphological analysis further suggesting induction of apoptosis. Pro-apoptotic effects were confirmed, as the extract enabled the activation of the effector caspase-3, broadening the knowledge on the anticancer mechanisms elicited by the fruits of X. aethiopica. Phenolic constituents might contribute to the cytotoxic effects, particularly via caspase-3 activation. Considering that X. aethiopica fruit is very often referred as an anticancer ingredient in Africa, but mainly the potent cytotoxicity herein recorded, our results call for additional research aiming to identify non-phenolic constituents contributing to the effects and also to further detail the anticancer mechanisms.

Acrylamide formation and antioxidant activity in coffee during roasting - A systematic study.

The aim of this study was to investigate the effect of the coffee roasting process on both toxic and some beneficial antioxidant compounds, applying a systematic and broad approach. Arabica and Robusta green coffee beans were roasted in a lab-scale roaster for different times in order to achieve five roasting degrees (from light to dark) and to assess the evolution of acrylamide (AA), trigonelline, nicotinic acid and caffeoylquinic acids contents (determined by HPLC) as well as antioxidant activity (evaluated by Folin-Ciocalteu, FRAP, DPPH, ABTS assays). The results confirmed that the AA levels and antioxidant activity reached a maximum in the first coffee roasting degrees and then decreased prolonging the heating process, both in Arabica and Robusta samples. Nevertheless, the thermal reduction observed was greater for AA compared to antioxidant activity, which was only slightly reduced due to the balance between the degradation and the neoformation of antioxidant compounds.

Optimization of espresso coffee extraction through variation of particle sizes, perforated disk height and filter basket aimed at lowering the amount of ground coffee used.

Espresso machines maintain constant the extraction process of espresso coffee (EC), however, it is difficult to grind roasted coffee in homogeneous way. This research aims to investigate grinded beans at specific particle sizes in three variously designed filter baskets and to compare the concentration of bioactive compounds while decreasing the amount of ground coffee. Analyses on caffeine, trigonelline and chlorogenic acids are carried out with HPLC-VWD, while volatiles with HS-SPME/GC-MS. Extracting with smaller particles escalates the quantity of bioactive compounds. The amount of caffeine/cup increased moving from 500-1000 µm to 200-300 µm particle size, both in Arabica and Robusta for all filter baskets. Keeping constant the volume of EC at various heights of perforated disc, the amount of bioactive compounds at 12 g were only around 9% lower than at 14 g. The outcomes will support further studies on different extraction processes, to develop more sustainable and economically affordable coffee.