Polyelectrolyte precipitation: a new green chemistry approach to recover value-added proteins from different sources in a circular economy context

Proteins have always been vital biological molecules used for industrial purposes, human nutrition and health. Nowadays, seeking new alternatives and sources of these biomolecules is becoming an increasing research trend derived from the present consumer awareness between food consumption and health promotion, but also on environmental sustainability. Although there are different consolidated/traditional downstream processes to obtain proteins, such as chromatography tools, alkali hydrolysis, precipitation by inorganic salts and organic solvents, their industrial-scale application still demands urgent innovation due to the poor recovery yields, high costs and time-consuming steps, environmental impact as well as some toxic concerns. Polyelectrolyte precipitation represents a green, innovative alternative for protein recovery; however, there are reduced data regarding its pilot or industrial-scale application. In this literature work, the action mechanism and principles with regards to its functionality and insights for its application on a big scale are reviewed. Overall, this review discusses the novelty and sustainability of protein precipitation by polyelectrolytes from different sources against traditional techniques as well as highlights the relationship between protein source, production relevance and bioactive properties that are key factors to maximize the application of this extractive method on a circular economy context.info:eu-repo/semantics/publishedVersio

Functional ingredients and additives from lemon by-products and their applications in food preservation: a review

Citrus trees are among the most abundant fruit trees in the world, with an annual production of around 124 million tonnes. Lemons and limes are among the most significant contributors, producing nearly 16 million tonnes per year. The processing and consumption of citrus fruits generates a significant amount of waste, including peels, pulp, seeds, and pomace, which represents about 50% of the fresh fruit. Citrus limon (C. limon) by-products are composed of significant amounts of bioactive compounds, such as phenolic compounds, carotenoids, vitamins, essential oils, and fibres, which give them nutritional value and health benefits such as antimicrobial and antioxidant properties. These by-products, which are typically discarded as waste in the environment, can be explored to produce new functional ingredients, a desirable approach from a circular economy perspective. The present review systematically summarizes the potential high-biological-value components extracted from by-products to achieve a zero-waste goal, focusing on the recovery of three main fractions: essential oils, phenolic compounds, and dietary fibres, present in C. limon by-products, and their applications in food preservation.info:eu-repo/semantics/publishedVersio

Incorporation of olive pomace ingredients in yoghurt as source of fibre and hydroxytyrosol: bioactivity and stability of throughout gastrointestinal digestion

Tânia I. B. Ribeiro thanks the Fundação para a Ciência e Tecnologia (FCT), Portugal for the PhD Grant SFRH/BDE/108271/2015, the financial support of BLC3 Association – Technology and Innovation Campus and the mentoring of Frulact and Comendador Arménio Miranda.info:eu-repo/semantics/publishedVersio

Management of fruit industrial by-products - a case study on circular economy approach

The management of industrial fruit by-products is important not only to decrease the volume of food waste accumulated in the landfills but also to develop strategies through reuse with the purpose to valorise and add economic value. The disposal of food waste leads to di erent global issues in di erent sectors, such as social, environmental and economical. These by-products represent a rich source of valuable compounds (polyphenols) with high antioxidant activity, which can be extracted through biotechnological methodologies for future industrial applications. In this context, the management of fruit by-products is challenged to move from a linear economy to a circular economy. Therefore, the purpose of this review is to provide a critical view of an integrated valorisation of fruit by-products to overcome a global issue, via the production of antioxidant extracts with high economic value. A case study of pineapple processing industrialization in a circular economy is explored and discussed.info:eu-repo/semantics/publishedVersio

Polyphenol extraction by different techniques for valorisation of non-compliant portuguese sweet cherries towards a novel antioxidant extract

Currently, there is special interest in the recovery of polyphenols from non-compliant fruits that have no market value; e orts to find value-added solutions for these food areas are a key option for a sustainable bio-economy. Saco cherries are a traditional Portuguese cherry variety, and although they are a nutritionally important food, rich in powerful dietary polyphenols, significant amounts of these cherries are not sold due to their small size. In this context, this work aimed to select the best method to produce novel antioxidant polyphenol-rich extracts from low calibre and non-compliant Saco cherries. Based on the results, microwaves-assisted extraction (MAE) allowed us to obtain a polyphenol-rich extract with a high antioxidant capacity (50.46 + 1.58 mg Trolox equivalent (TE)/g dry extract (DE) by oxygen radical absorbance capacity (ORAC), 10.88 + 0.38 mg ascorbic acid equivalent (AA)/g DE by 2-azinobis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), and 9.58 + 0.42 mg TE/g DE by 2,2-diphenyl-1-picrylhydrazyl (DPPH)) and a high content of polyphenols, namely, hydroxycinnamic acids (neochlorogenic and p-coumaric acids) and anthocyanins (cyanidin-3-rutinoside and cyanidin-3-glucoside), compared with those of conventional extractions with low and high temperature and ultrasound-assisted extraction. The antioxidant extract produced from MAE could be a new alternative for the valorisation of non-compliant cherries since these extracts proved to be a functional ingredient due to the high content of antioxidants, which are linked to the prevention of diseases.N/Ainfo:eu-repo/semantics/publishedVersio

Impact of simulated in vitro gastrointestinal digestion on bioactive compounds, bioactivity and cytotoxicity of melon (Cucumis melo L. inodorus) peel juice powder

The objectives of this research work were to evaluate the effect of in vitro gastrointestinal digestion (GIT) on melon peel juice (MPJ) powder from fruit processing industry by-products, considering (i) the recovery and accessibility indexes, (ii) the changes on antioxidant activity, and (iii) the prebiotic effect. Throughout exposition to GIT conditions a decrease on the total phenolic content (TPC = 65.31%) and antioxidant activity by ABTS = 39.77% and DPPH = 45.91% were observed. However, these both parameters exhibited stable accessibility, accounting with 81.89%, 76.55%, and 54.07% for TPC, ABTS and DPPH, respectively. After gastrointestinal digestion, the non-absorbed fraction exhibited a positive impact on the growth of Bifidobacterium and Lactobacillus strains, possibly associated with the high content of simple sugar (glucose and fructose). This fraction also showed to be safe on Caco-2 intestinal cells. These findings suggest that MPJ might be used as a potential food functional ingredient.info:eu-repo/semantics/publishedVersio

Impact of extraction process in non-compliant ‘Bravo de Esmolfe’ apples towards the development of natural antioxidant extracts

The ‘Bravo de Esmolfe’ apple (BE) is rich in antioxidants and represents one of the most important traditional cultivars in Portugal. A large amount of non-compliant BE, with no market value, it is generated every year. Thus, an effort to find value-added solutions is of utmost importance. For the first time, green extraction (microwave-assisted-extraction (MAE) and ultrasound-assisted-extraction (UAE)) were compared against conventional extraction (with (CET) and without temperature (CE)) to select the most efficient process to produce a natural antioxidant extract from non-compliant BE. The results showed that MAE and CET are good methodologies for developing a BE antioxidant extract. However, MAE is more sustainable than CET, requiring less time to reach high temperatures. The MAE-extract showed great antioxidant activity (14.80 ± 0.70 mg TE/g DE by ORAC, 3.92 ± 0.25 mg AAE/g DE by ABTS, and 5.11 ± 0.13 mg TE/g DE by DPPH). This extract revealed high amount of chlorogenic acid (0.48 ± 0.07 mg/g DE), (-)-epicatechin (0.30 ± 0.02 mg/g DE) and phloridzin (0.13 ± 0.01 mg/g DE). This study shows that non-compliant BE is a useful source of antioxidants, being a sustainable way for the recovery of value-added compounds from the rejected fruit in line with sustainable and circular bioeconomy principles.info:eu-repo/semantics/publishedVersio

Impact of functional flours from pineapple by-products on human intestinal microbiota

Solid fractions from pineapple stems and peels are constituted by structural carbohydrates coupled with dietary fibre, simple sugars, but also vitamins and polyphenols, which together can have potential effects on human health. The present studies report for the first time the bioavailability and bioaccessibility of pineapple by-products fractions throughout simulated gastrointestinal tract, evaluates prebiotic potential and in vitro human microbiota fermentation. The pineapple flours promoted the human faeces fermentation through growth of beneficial strains, being corroborated by the decrease of simple sugars and the production of healthy organic acids (acetic, propionic and butyric acids) - well known short chain fatty acids. On the other hand, a high phenolic compounds content was release through flours digestion, developing an antioxidant environment within human gut. Thus, was possible to conclude that pineapple flour promoted a positive modulation in the overall system, proving a synergetic interaction of dietary fibre and polyphenols upon human microbiota.This work wasfinancially supported by BiValBi - Biotechnologies toValorise the regional Biodiversity in Latin America, in the funding project FP7-PEOPLE-2013-IRSES PEOPLE Marie Curie Program through project reference PIRSES-GA-2013-611493. We would like to thank thescientific collaboration of CBQF under the FCT–Fundação para aCiência e a Tecnologia with project Multibiorefinery–Multi-purposestrategies for the valorisation of a wide range of agroforestry by-pro-ducts andfisheries: A step forward in the creation of an integratedbiorefinery, (POCI-01-0145-FEDER-0066), project UID/Multi/50016/2013 and by PhD grant SFRH/BD/104074/2014 to Débora Campos.info:eu-repo/semantics/publishedVersio

Natural-based antioxidant extracts as potential mitigators of fruit browning

Fruit enzymatic browning (EB) inhibition continues to be a challenge in the Food Industry. This physiological disorder results mainly from the oxidation of natural phenolic compounds by polyphenoloxidase (PPO) and peroxidase (POX) leading to the formation of brown pigments. EB can be controlled with the application of antioxidants, reducing/inhibiting the activity of these oxidative enzymes. In this study, strawberry tree (leaves and branches) and apple byproduct were the natural-based extracts (NES) selected, as potential tissue browning inhibitors, within a first screening of fifteen natural-based extracts with antioxidant properties. Phenolic profile, total phenolic content and antioxidant activity of the selected extracts were also performed as well as their depletion effect on the oxidative enzyme’s activity and browning inhibiton in fresh-cut pears. Strawberry tree extracts (leaves and branches) revealed higher total phenolic content (207.97 ± 0.01 mg GAE.gNES−1 and 104.07 ± 16.38 mg GAE.gNES−1, respectively), confirmed by the plethora of phenolic compounds identified by LC-ESI-UHR-QqTOF-HRMS and quantified by HPLC. This phytochemical composition was reflected in the low IC50 against PPO and POX obtained. Despite the lower phenolic content (6.76 ± 0.11 mg GAE.gNES−1) and antioxidant activity (IC50 = 45.59 ± 1.34 mg mL−1), apple byproduct extract showed potential in delaying browning. This study highlights the opportunity of byproducts and agricultural wastes extracts as novel anti-browning agents.info:eu-repo/semantics/publishedVersio

Development of a UPLC-MS/MS method for establishing Serra da Estrela´s free amino acids profile

Associate Laboratory LSRE-LCM-UID/EQU/50020/2019,strategic funding UID/BIO/04469/2019-CEB and BioTecNorte operation (NORTE-01-0145-FEDER-000004), strategic project PEst-OE/AGR/UI0690/2014–CIMOand by Project 02/SAICT/ 2016/23290-QCLASSE, funded by national funds through FCT/MCTES (PIDDAC)info:eu-repo/semantics/publishedVersio