The industrial production of orange juices generates large amounts of wastes highly rich in polyphenolic compounds with great antioxidant properties. Hence, in the framework of circular economy, orange residues result in a excellent source of valuable by-products that can be recovered and purified to be further used in pharmaceuticals, nutraceuticals and functional foods.

In this work, orange wastes consisting of solid mixtures of skin and pulp residues have been treated with water and hydroalcoholic solutions under mechanical shaking to recover the polyphenolic components. The resulting extracts have been centrifuged and filtered, and solutions obtained have been analyzed chromatographically to try to identify the most remarkable phenolic species they contain. The analytical method relies on reversed phase (C18) liquid chromatography with UV/vis and mass spectrometric (MS) detection using 0.1% formic acid in water and acetonitrile as the components of the mobile phase. Chromatograms have been acquired with UV detection at 280, 325 and 370 nm, and MS (low and high resolution) detection with different acquisition modes, including full scan, data-dependent acquisition (DDA) and multiple reaction monitoring (MRM).

Results have confirmed the presence of astilbin, p-coumaric acid, rutin, ferulic acid, diosmin, caffeic acid, hesperetin, naringenin and hesperidin, which have also been quantified using HPLC-MS. Hesperidin is the major compound in the extract solutions, with a concentration of about 30 mg L^-1. Naringenin and hesperetin are found at concentrations of about 13 and 3 mg L^‑1, respectively, and the rest of the compounds are found at concentrations below 1 mg L^‑1.

Honey is a natural food product well known for its high nutritional value. Apart from sugars, it contains phytochemicals, including polyphenols and flavonoids that are compounds with highly demonstrated antimicrobial and antioxidant capacities.

The main goal of this work is the development of an analytical methodology to obtain the polyphenolic profile of honeys from different varieties and pollen sources. To isolate the target compounds from the samples, miniaturized vortex (VE) and ultrasound assisted extraction (UAE) employing aqueous solvent followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) were employed. Results revealed that more than 20 different polyphenols of the 40 target were detected in the analyzed samples, reaching total concentrations up to hundreds of µg g^-1. Other indexes such as the total polyphenolic content (TPC) and antioxidant activity (AA) were also evaluated by spectrophotometric techniques.

ANOVA and PCA based on the results from TPC, AA and individual polyphenols concentration showed that significant differences appeared depending on the honey variety, being several of the identified polyphenols, especially hydroxycinnamic acids, responsible of the main differentiation. PCA revealed that two components were enough to explain more than 90% of variance and honey classification in 6 different groups, attending to the presence of individual polyphenols, was successfully obtained showing that the combination of chromatographic analysis, mass spectrometry detection and PCA are suitable tools to investigate the botanical authentication of honey.

Acknowledgement. This research was supported by project GO FEADER 2018/054B (Xunta de Galicia). The authors belong to the National Network for the Innovation in miniaturized sample preparation techniques, RED2018-102522-T (Ministry of Science, Innovation and Universities, Spain), and to the Galician Competitive Research Groups IN607B 2019/13 and ED431 2020/06 (Xunta de Galicia). This study is based upon work from the Sample Preparation Study Group and Network, supported by the Division of Analytical Chemistry of the European Chemical Society. All these programmes are co-funded by FEDER (EU). Authors would like to acknowledge the Regulator Council of Galician Honey (IXP, Mel de Galicia) for collecting and supplying the samples.

The leaves of the coffee plant (genus Coffea) are traditionally used in several countries worldwide to prepare tea-like beverages using aqueous infusion in hot water. Since 1 July 2020, the placing on the market of coffee leaf tea was authorized in the European Union (EU) under the framework of the novel food regulation. The implementing regulation for coffee leaf tea established several conditions of use, including maximum amount of dried leaves per litre of water, a necessary pasteurisation step and several chemical requirements including maximum levels for chlorogenic acid, caffeine and epigallocatechin gallate. To date, there are no standard methods available to control these parameters to check the regulatory compliance of coffee leaf tea. In this presentation, we have for the first time evaluated standard methods for Camellia sinensis tea analysis for transferability to coffee leaf tea. The results showed that the methods for polyphenol and catechin analysis could be transferred without modifications to coffee leaf tea. The only difference found was a much lower content of some catechins in coffee leaf tea compared to Camelia sinensis tea, but the methods were clearly applicable to be used to control the EU’s maximum limits for coffee leaf tea. None of the samples obtained from India and El Salvador exceeded the limits and all were found to comply with the EU regulation. Furthermore, standard European tea brewing methods using 90-95°C hot water will ensure the EU’s necessary pasteurisation conditions (at least 71°C for 15 seconds).

Liposomes are made up of lipid bilayers that can enclose both hydrophilic and hydrophobic active ingredients. They act as drug vehicles for the effective delivery of small molecules to their targeted cells. Most of the vitamins are susceptible to degradation when exposed to adverse conditions, hence it is often enclosed within a membrane to prevent deterioration and ensure maximum uptake. A computational study on the ligand-receptor interaction will provide comprehensive knowledge about the bilayer composition that will aid in liposome structuring. To this context, the docking of vitamins (B12, B9, A, D) with the lipid bilayer membrane was investigated using Autodock Vina. The docking studies were further coupled with molecular dynamics simulation for 3ns (MDS) to analyze the energies. The binding interaction of vitamins with the lipid membrane influences the bioavailability and affects its diffusion across the membranes determining the stability. Hydrophobic vitamins showed a stronger binding affinity with the membranes varying from 10.8 – 12.7 kcal/mol. Hydrophilic vitamins had a weaker binding affinity 5.1-5.7 kcal/mol. Few unfavorable bonds were observed in hydrophilic vitamins. Electrostatic force showed a stronger influence over the molecules than Van der Waals attraction. The diffusion coefficient (× 10-5) suggests there might be a formation of a leaky membrane. Docking study of these vitamins with the lipid bilayer membrane provides information about the ligands' binding affinity (RMSD ~ 0.00) and its interaction nature in the receptor pockets. Hence, simultaneous co-encapsulation of hydrophilic and hydrophobic cavities can be a promising strategy to improve the delivery of multi-micronutrients.

Background: The bacteriocins produced by lactic acid bacteria (LAB) are candidates for application as food biopreservatives and as an alternative of antibiotics. The antimicrobial activities against pathogenic and spoilage bacteria are one of the properties of bacteriocins.

In the present study, the bacteriocins produced by three strains of LAB were studied and characterized: enterocins CM9 (Enterococcus sp CM9), enterocins CM18 (Enterococcus sp CM18) and enterocins H3 (Enterococcus sp H3).

Method: A number of fifteen of different pathogenic bacteria was tested for antimicrobial activity. The spot agar and well diffusion methods were used. The well diffusion method was also used for the characterization of enterocins, by studying the effect of pH, heat and chemical agents on the activity of enterocins.

Results: The LAB used in the present work, showed an inhibitory activity against all pathogenic bacteria tested. The supernatant of LAB exhibited an inhibitory activity against Listeria monocytogenes, Escherichia coli and Salmonella Typhimirium. The enterocins produced by the three strains of LAB appeared stable to adjustment of pH and were resistant to heat, showing their thermostability. Excepting the Triton X100, they remained stable after treatment with Tween 20 and 80, NaCl, SDS, urea and EDTA.

Conclusion: The results indicate that the enterocins CM9 and CM18 belong to class IIa bacteriocin and present a wide inhibitory spectrum. The biological properties of the three strains of LAB suggest that these strains merit further investigations so they can be applied in public and veterinary health programs.

Olive stones (OS) are a by-product generated in the olive oil production process. This residue is obtained in the industries after the oil extraction process and it is recognized as an interesting feedstock for the production of bioenergy and value-added products. Nevertheless, currently it is only used as low-cost solid biofuel for combustion.
An alternative valorization approach has been developed based on an acid catalyzed process for the solubilization of hemicelluloses [1] and the production of furfural [2]. This process yields a solid cellulose and lignin-rich material, that can be further upgraded.
In this work, an organosolv process for delignification of the material and improvement of the enzymatic digestibility was applied and optimized. The organosolv stage was carried out with an ethanol:water ratio (50:50, w/w) in a Parr reactor, varying the temperature (140-190 °C) and the addition of catalyst (0-100 mM H2SO4). The liquid fraction obtained was analyzed to evaluate the presence of value-added products, such as phenolic compounds with antioxidant activity.
The total phenolic content was determined by the Folin-Ciocalteu method, obtaining a phenol concentration between 5 and 12 g GAE/L, of which between 2 and 6 g/L are tannins, corresponding to a phenol yield of 7 g GAE/100 g of processed material, which ranks is in the range of the obtanided from other plant sources, in other olive by-products such as exhausted olive pomace, up to 9 g GAE/100g of extract have been reported [3]. Phenolic profile was obtained by capillary electrophoresis analysis, allowing the identification, among others, of vanillin and syringaldehyde as naturally occurring flavor components exhibiting antioxidant and antimicrobial properties.
Therefore, with the present study, we were able to determine that the liquor obtained after organosolv pretreatment of olive stones can be also valued as a bio-source of non-synthetic preservatives and additives for the food industry.

References
1. Padilla-Rascón, C.; Ruiz-Ramos, E.; Romero, I.; Castro, E.; Oliva, J.M.; Ballesteros, I.; Manzanares, P. Valorisation of Olive Stone By-Product for Sugar Production Using a Sequential Acid/Steam Explosion Pretreatment. Ind. Crops Prod. 2020, 148, 112279, doi:10.1016/j.indcrop.2020.112279.
2. Padilla-Rascón, C.; Romero-García, J.M.; Ruiz, E.; Romero, I.; Castro, E. Microwave-Assisted Production of Furfural from the Hemicellulosic Fraction of Olive Stones. Process Saf. Environ. Prot. 2021, 152, 630–640, doi:10.1016/j.psep.2021.06.035.
3. Gómez-Cruz, I.; Romero, I.; Contreras, M. del M.; Padilla-Rascón, C.; Carvalheiro, F.; Duarte, L.C.; Roseiro, L.B. Exhausted Olive Pomace Phenolic-Rich Extracts Obtention: A First Step for a Biorefinery Scheme Proposal. Proceedings 2020, 70, 10, doi:10.3390/foods_2020-07612.

The winemaking industry produces large volumes of waste and by-products, among these, pomace is an important source of bioactive molecules like polyphenols, dietary fiber, unsaturated fatty acids, etc. Only small amount of this by-product is recycled thus potentially resulting in an environmental problem. Over the last years, the evaluation of grape pomace flour as functional alternative ingredient and its recovery into value-added food products have attracted great interest. In this study fortified pasta was prepared through the replacement of durum wheat semolina with 5 % of pomace flour from one white grape cultivar (Fiano) and two red grape cultivars (Aglianico and Lambrusco). Fortified uncooked and cooked pasta samples were characterized by bioactive molecule content and profile. High Performance Liquid Chromatography analysis of both soluble and bound phenols, tocochromanols and carotenoids were performed. In uncooked pasta fortified with both white and red grape pomace significantly increased the soluble phenolic molecules content while the content of bound phenols increases slightly in pasta added with red grape pomace only. During cooking process, the bound phenols were lost, while soluble phenols showed a net increase both in control and fortified pasta samples. Moreover cooked fortified pasta showed a higher soluble phenolic content than the control. Both tocochromanols and carotenoids showed a net increase in uncooked pasta added with either white grape pomace or red grape pomace. In the cooked samples, tocochromanol and carotenoid content slightly decreased; despite the losses, cooked pasta still presented a significative higher content of these molecules with respect to the control. These results show that pasta fortified with Fiano, Aglianico and Lambrusco grape pomace flour could represent a food product enriched with functional molecules and a potential technological alternative for the food industry by-products re-use.

The development of multidrug-resistant bacterial strains is a worldwide emerging problem that needs a global solution. Exploring new natural antibiofilm agents is one of the most important alternative therapies in combating bacterial infections. This study aimed at testing the antimicrobial potential of Eucalyptus sideroxylon flowers extract (ESFE) against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans prior to testing the antibiofilm activity against S. aureus, P. aeruginosa and C. albicans. ESFE demonstrated antimicrobial activity and promising inhibition activity against methicillin-resistant S. aureus (MRSA) biofilm formation up to 95.9% (p < 0.05) at a concentration of 0.05 mg/mL and eradicated C. albicans biofilm formation up to 71.2% (p < 0.05) at a concentration of 0.7 mg/mL. LC-MS analysis allowed the tentative identification of eighty-three secondary metabolites: 21 phloroglucinol, 18 terpenes, 16 flavonoids, 7 oleuropeic acid derivatives, 7 ellagic acid derivatives, 6 gallic acid derivatives, 3 phenolic acids, 3 fatty acids and 2 miscellaneous. In conclusion, E. sideroxylon is a rich source of effective constituents that promote its valorization as a promising candidate in the management of multidrug-resistant bacterial infections.

Microbial resistance inhibition is increasingly focused on the use of plant extracts and their phytochemicals as candidates for targeting virulence factors. Here, we report on the chemical composition and virulence inhibition potential of both polar (PF) and non-polar fractions (NPF) of the underground parts of three common Iris species (I. confusa, I. pseudacorus and I. germanica). The anti-haemolytic and biofilm inhibition potentials of the aforementioned Iris species on methicillin resistant and sensitive (MRSA and MSSA) S. aureus bacterial strains were explored. I. pseudacorus PF exhibited the most potent effect against S. aureus haemolytic activity. Intriguingly, all the tested fractions from all species, except I. pseudacorus NPF, have no significant inhibition on the biofilm formation of MRSA and MSSA. Metabolite profiling of the investigated species revealed ninety and forty-five metabolites detected in the PFs and NPFs, respectively. Nigricin-type, tectorigenin-type isoflavonids and xanthones allowed the discrimonation of I. pseudacorus underground parts PF from the other species, highlighting the importance of those metabolites in exerting its promising activity. On the other hand, triterpene acids, iridals, triacylglycerols, ceramides, and acid represented the metabolites detected in highest abundance in I. pseudacorus NPF.

Introduction: Sulfur dioxide has been traditionally used in winemaking as an effective preservative even though it often has negative taste and health-related effects on consumers, particularly when used in excess. Furthermore, it can induce both the SO₂-related resistance and the SO₂-related viable but not culturable (VBNC) state of different wine yeast and bacteria species. Currently, sulfur dioxide replacement by plant-derived compounds, used as food bio-preservatives, has been proposed in winemaking, at laboratory scale, as a green and healthier alternative.

Purpose: To replace sulfur dioxide with p-coumaric acid, a plant-derived phenolic compound, in winemaking on an industrial scale in order to produce a safe, natural wine that is more sustainable, genuine and healthier.

Methods: Winemaking of both sulfur dioxide- and p-coumaric acid-treated wine was conducted in parallel at a winery on an industrial scale (into two 10,000 L stainless steel tanks) using the same quantity of the same grape variety (10,000 kg of Lemnos Island organic white wine grapes, Muscat of Alexandria) during the harvest of 2019 and following the same oenological procedures. The influence of p-coumaric acid on wine properties and quality has been compared with that of sulfur dioxide under the same conditions, after 3 months of storage in a bottle. To this end, several analytical parameters of wine related to oenological, microbiological, antioxidant, sensory and safety properties were determined according to the International Standards Organization (ISO) and International Organization of Vine and Wine (OIV) official analytical methods for both wine samples.

Results: In general, there were no significant differences observed in stability, microbiological, antioxidant and oenological profiles due to sulfur dioxide replacement by p-coumaric acid, while the sensory profile was slightly ameliorated.

Significance: This replacement technology resulted in a suitable green alternative to sulfur dioxide and could be easily applied by the wine industry in order to guarantee high quality green products.