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Olive oil production and consumption has been increasing due to its organoleptic properties and health benefits. Consequently, waste generation also raised leading to environmental concerns. Nevertheless, this waste contains high amounts of bioactive compounds with potential to be extracted, recovered, and applied, following circular economy policies. New extractive technologies, especially green ones, are important for the success of this venture. This review focuses on the olive oil production chain, from the tree to olive oil and the respective waste/by-products, presenting and discussing emergent and green methodologies to recover and give new life to bioactive compounds that are usually discarded. Oleuropein, hydroxytyrosol, and other related compounds are molecules with important biological activities. They can be recovered in high concentrations through such technologies and used successfully in different industries to meet the sustainability and circular economy principles of the chain. [ABSTRACT FROM AUTHOR]

Produced water (PW) is an effluent from the petrochemical industry that has a significant environmental impact due to its high salinity and presence of chemical compounds and heavy metal. Microalgae have been considered promising to phytoremediation of this effluent and producing biomass with high added value. Therefore, this study aimed to stimulate the production of biomass and biomolecules from Chlorella vulgaris by supplementation with PW and evaluate the synergistic effect of sources of physical and chemical stress. C. vulgaris was cultivated in different PW concentations of PW (not autoclaved) and BG11 medium under a 24 h photoperiod, with inoculum pre-adapted the same photoperiod. The culture containing 70% of BG11 and 30% PW (PW 30%) was the most viable, with a biomass production of 1.35 g/L and a higher concentration of carbohydrates (37.46%) and ash (18.21%) than the control culture (100% BG11). Furthermore, PW 30% also resulted in considerable amounts of lipids (9.92%), proteins (21.94%), chlorophyll-a (6.64 μg/mL), chlorophyll-b (10.57 μg/ mL), and carotenoids (21.38 μg/mL). The major fatty acids were C18:3n6 (21.50%), C20:0 (19.96%), C16:0 (17.12%), and C18:0 (12.15%). The PW 30% treatment showed removal efficiencies for iron (61.80%), chlorides (79.64%), phosphates (97.18%), and petroleum hydrocarbons including total petroleum hydrocarbons (TPH; 45.39%) and resolved petroleum hydrocarbons (RPH; 57.57%). The analyzed fuel properties presented an ideal profile for the production of biodiesel and bioethanol, which can be obtained from carbohydrates. Simultaneously, treatment PW 30% resulted in the production of biomolecule-rich in biomass in addition to the bioremediation effect. [ABSTRACT FROM AUTHOR]

Natural preservatives were predominantly developed to eliminate the use of synthetic preservatives for food and agriculture industries. Multi-component nanoemulsions (MCN) with significant antibacterial activity should be proper candidates as natural preservatives. This research aimed to formulate a multi-component phospholipid-based nanoemulsion (PNE) with prolonged shelf-life loaded with a mixture of Eucalyptus globulus and Mentha piperita essential oils (EOs). The effects of different chemical and mechanical conditions (ultrasonication) on the stability of MCN were evaluated. The emulsions were monitored from day 1 to 730, and stable formulae were investigated for around two years. The Zeta potential confirmed the anionic surface charge. Dynamic light scattering and transmission light scattering revealed a droplet size ranging between 93.40 and 100.00 nm. A homogeneous formula was stable for more than 730 days. Ultrasonication treatment and 1% v/v of food-grade castor oil as co-emulsifier were critical in fabricating stable formulae. Minimum inhibitory concentration (MIC) values of 31, 8, and 63 µg/ml were observed against Escherichia coli, Staphylococcus aureus and Salmonella enteritidis, respectively. The results showed a significant reduction in MIC values of 32-, 250-, 15-fold against E. coli, S. aureus and S. enteritidis, respectively, compared to an original mixture of essential oils. The mass transfer followed a case-I transfer (Fick law diffusion) evaluated by Koresmeyer-Peppas kinetic model (R2 = 0.88). In conclusion, MCN could be a promising candidate for natural preservatives to be used in the food, agriculture and cosmetic industries. [ABSTRACT FROM AUTHOR]

Inadequate wastewater management can cause negative impacts on the ecosystem, becoming an obstacle to aquaculture growth. New technologies have been developed to reduce the nutrient load in aquaculture wastewater involving microalgae as phytoremediation agents. In addition to reducing the nutrient load of water bodies, the microalgae‐based phytoremediation can also generate high‐added value biomass. Arthrospira (Spirulina) is a little‐explored genus as a phytoremediation agent for aquaculture wastewater, representing about 30% of the biomass produced in the world that is known for its high concentration of proteins, carotenoids and phycocyanin. Using the aquaculture wastewater is an important strategy to reduce the production costs, obtain high‐added value biomolecules and mitigate the effects of wastewater on the aquatic ecosystem. However, there are few reports of Arthrospira sp. as a remediation agent for aquaculture wastewater that assesses the biochemical composition. This manuscript aimed to review the cellular mechanisms of phytoremediation and the biochemical composition of Arthrospira currently described when grown in aquaculture wastewater. [ABSTRACT FROM AUTHOR]

DNA-based methods have been advanced as excellent alternatives for the detection and quantification of gluten-containing cereals. In this study, it was intended to evaluate the effect of three distinct food matrices on the performance three TaqMan real-time PCR approaches targeting α2-gliadin, agglutinin isolectin (Tri a 18) and thioredoxin h(Tri a 25) genes of wheat. The results of wheat flour detection in soya bean, maize and rice model matrices evidenced that sensitivity was considerably affected by both the food matrix and the target gene. Rice matrix allowed the highest sensitivity, in opposition to soya bean. The α2-gliadin method enabled the best sensitivity, especially when combined with rice matrix (5 mg kg−1), followed by maize (10 mg kg−1) and soya bean (50 mg kg−1). These findings suggest that food matrix effects need to be carefully evaluated when developing real-time PCR assays for wheat detection/quantification, but without compromising their great effectiveness as tools to monitor gluten-containing cereals. [ABSTRACT FROM AUTHOR]

Abstract Bacteria that are capable of accumulating lipids in their cells as storage compounds can also produce polyhydroxyalkanoates of high technological value, depending on the specific culture conditions. The objective of this study was to utilize crude glycerol from biodiesel (CGB) as a substrate, which is a major byproduct from biodiesel production, to produce lipophilic compounds. Bacillus megaterium INCQS 425 was cultivated and evaluated for the production of lipophilic compounds and the properties of these compounds were investigated. Cultivation of the bacteria in a medium with a C:N ratio of 0.60:1 favored the accumulation of lipids by (17.5%) comprising mainly palmitic acid (13.08%), palmitoleic (39.48%), and especially oleic acid (37.02%), which imparts good characteristics to biodiesel. Meanwhile, cultivation of the bacteria in a medium with a C:N ratio of 4:1 favored the accumulation of polyhydroxyalkanoates (PHA) (3.31 g L−1) mainly comprising medium and long chain PHA. Low crystallinity (<30%) and excellent thermal properties make them suitable for processes that demand high temperatures, such as extrusion. The lipids produced in the present study had satisfactory oxidative stability for the production of quality biodiesel. The polyhydroxyalkanoates produced in the study are of low cost and have promising thermal properties that justify its technological potential, thereby configuring highly competitive bioproducts. [ABSTRACT FROM AUTHOR]

In this study, we investigated the cellular fatty acid profiles of different Xanthomonas pathovars producing xanthan gum and explored the fatty acid composition to identify chemical markers of xanthan gum productivity and quality. Three Xanthomonas pathovars were studied. The fermentation was conducted for 168 h. Samples from the fermented medium were collected for extraction, quantification, and characterization of xanthan. The unsaturated/saturated (U/S) fatty acid ratio in Xanthomonas cells during fermentation was correlated with production, viscosity, and molecular weight of the gum obtained at each 24 h. The Xanthomonas axonopodis pv manihotis 290 strain showed a higher U/S ratio for major cell fatty acids (C16:1ω7/C16:0) as compared with the other two strains; this high ratio was directly associated with xanthan production. No correlation was observed between cellular fatty acid composition and characteristics of xanthan synthesized. Thus, it was possible to determine a production chemical marker for xanthan gum in Xanthomonas strains. [ABSTRACT FROM AUTHOR]

Alfalfa ( Medicago sativa) has been extensively used as animal feed, due to its fiber, protein, minerals, and vitamins, being also a useful source of phenolic compounds with potential therapeutic benefits. Nevertheless, its potential use as human ingredient is scarce. The aim of this work was to assess the nutritional composition, amino acid profile, and antioxidant capacity (AOC) of freeze-dried juice (FDJ) and fibrous residual material (RM), two new alfalfa-derived products (Adps) recently launched as ingredients for beverage preparations. Results demonstrated a high content of proteins (23-30 g/100 g FDJ and 13-17 g/100 g RM), crude fiber (29 g/100 g RM), and minerals (such as sodium, calcium, iron, and zinc). No significant difference was found in caloric content (4 kcal/g). Essential and nonessential amino acids were quantified in both Adps being leucine and lysine the most abundant. Total phenolic and total flavonoid contents (TPC and TFC, respectively) and their changes along the different harvesting periods of the year were also examined. FDJ presented the highest TPC in May (19 mg gallic acid equivalents/g dry weight [dw]), while in October TFC had the maximum value (4 mg catechin equivalents/g dw). Both products exhibited an interesting AOC by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power assays. This study reports the nutraceutical potential of two new types of Adps. [ABSTRACT FROM AUTHOR]

This work describes the development of an electrochemical enzymatic biosensor for quantification of the pesticide formetanate hydrochloride (FMT). It is based on a gold electrode modified with electrodeposited gold nanoparticles and laccase. The principle behind its development relies on FMT's capacity to inhibit the laccase catalytic reaction that occurs in the presence of phenolic substrates. The optimum values for the relevant experimental variables such as gold nanoparticles electrochemical deposition (at −0.2V for 100s), laccase immobilization (via glutaraldehyde cross-linking), laccase concentration (12.4mg/mL), substrate selection and concentration (5.83×10−5 M of aminophenol), pH (5.0), buffer (Britton–Robinson), and square-wave voltammetric parameters were determined. The developed biosensor was successfully applied to FMT determination in mango and grapes. The attained limit of detection was 9.5×10−8 ±9.5×10−10 M (0.02±2.6×10−4 mg/kg on a fresh fruit weight basis). Recoveries for the five tested spiking levels ranged from 95.5±2.9 (grapes) to 108.6±2.5% (mango). The results indicated that the proposed device presents suitable characteristics in terms of sensitivity (20.58±0.49A/μM), linearity (9.43×10−7 to 1.13×10−5 M), accuracy, repeatability (RSD of 1.4%), reproducibility (RSD of 1.8%) and stability (19days) for testing of compliance with established maximum residue limits of FMT in fruits and vegetables. [ABSTRACT FROM AUTHOR]

Abstract: An accurate and sensitive method for determination of 18 polycyclic aromatic hydrocarbons (PAHs) (16 PAHs considered by USEPA as priority pollutants, dibenzo[a,l]pyrene and benzo[j]fluoranthene) in fish samples was validated. Analysis was performed by microwave-assisted extraction and liquid chromatography with photodiode array and fluorescence detection. Response surface methodology was used to find the optimal extraction parameters. Validation of the overall methodology was performed by spiking assays at four levels and using SRM 2977. Quantification limits ranging from 0.15–27.16ng/g wet weight were obtained. The established method was applied in edible tissues of three commonly consumed and commercially valuable fish species (sardine, chub mackerel and horse mackerel) originated from Atlantic Ocean. Variable levels of naphthalene (1.03–2.95ng/g wet weight), fluorene (0.34–1.09ng/g wet weight) and phenanthrene (0.34–3.54ng/g wet weight) were detected in the analysed samples. None of the samples contained detectable amounts of benzo[a]pyrene, the marker used for evaluating the occurrence and carcinogenic effects of PAHs in food. [Copyright &y& Elsevier]

Abstract: In this work, a microwave-assisted extraction (MAE) methodology was compared with several conventional extraction methods (Soxhlet, Bligh & Dyer, modified Bligh & Dyer, Folch, modified Folch, Hara & Radin, Roese-Gottlieb) for quantification of total lipid content of three fish species: horse mackerel (Trachurus trachurus), chub mackerel (Scomber japonicus), and sardine (Sardina pilchardus). The influence of species, extraction method and frozen storage time (varying from fresh to 9months of freezing) on total lipid content was analysed in detail. The efficiencies of methods MAE, Bligh & Dyer, Folch, modified Folch and Hara & Radin were the highest and although they were not statistically different, differences existed in terms of variability, with MAE showing the highest repeatability (CV=0.034). Roese-Gottlieb, Soxhlet, and modified Bligh & Dyer methods were very poor in terms of efficiency as well as repeatability (CV between 0.13 and 0.18). [Copyright &y& Elsevier]

Abstract: The concentrations of 18 polycyclic aromatic hydrocarbons (PAHs) were determined in three commercially valuable fish species (sardine, Sardina pilchardus; chub mackerel, Scomber japonicus; and horse mackerel, Trachurus trachurus) from the Atlantic Ocean. Specimens were collected seasonally during 2007–2009. Only low molecular weight PAHs were detected, namely, naphthalene, acenaphthene, fluorene and phenanthrene. Chub mackerel (1.80–19.90μg/kgww) revealed to be significantly more contaminated than horse mackerel (2.73–10.0μg/kgww) and sardine (2.29–14.18μg/kgww). Inter-specific and inter-season comparisons of PAHs bioaccumulation were statistically assessed. The more relevant statistical correlations were observed between PAH amounts and total fat content (significant positive relationships, p ⩽0.05), and season (sardine displayed higher amounts in autumn–winter while the mackerel species showed globally the inverse behavior). The health risks by consumption of these species were assessed and shown to present no threat to public health concerning PAH intakes. [Copyright &y& Elsevier]

Olive pomace, an olive oil processing byproduct, can be upcycled and meet the current demand for natural and sustainable food ingredients. In this work, a patented process was used to obtain a functional ingredient from different olive pomaces. The nutritional, chemical and antioxidant profiles, as well as the antimicrobial activity against S. aureus, E. coli and C. albicans, were investigated for the first time. The amount of phenolics ranged between 3.1 and 3.8 g gallic acid eq./100 g in all samples and flavonoids between 2.0 and 3.2 g catechin eq/100 g. No significant differences were found regarding the antioxidant activity. The total fat varied between 5 and 11%, α-tocopherol being the major vitamer and oleic acid the main fatty acid. The protein and ash contents were 1–4% and 10–17%, respectively. The functional ingredient with a higher hydroxytyrosol content (220 mg/100 g) also presented the best minimal inhibitory concentration against the tested bacteria. No activity against C. albicans was verified. This new functional ingredient presents the potential to be used as a natural preservative or as a nutritional profile enhancer. Moreover, it can be an advantageous ingredient in food products, since it comprises specific lipid and hydrophilic bioactive compounds usually not present in other plant extracts. [ABSTRACT FROM AUTHOR]

Olive pomace is a semisolid by-product of olive oil production and represents a valuable source of functional phytocompounds. The valorization of agro-food chain by-products represents a key factor in reducing production costs, providing benefits related to their reuse. On this ground, we herein investigate extraction methods with supercritical carbon dioxide (SC-CO2) of functional phytocompounds from olive pomace samples subjected to two different drying methods, i.e., freeze drying and hot-air drying. Olive pomace was produced using the two most common industrial olive oil production processes, one based on the two-phase (2P) decanter and one based on the three-phase (3P) decanter. Our results show that freeze drying more efficiently preserves phytocompounds such as α-tocopherol, carotenoids, chlorophylls, and polyphenols, whereas hot-air drying does not compromise the β-sitosterol content and the extraction of squalene is not dependent on the drying method used. Moreover, higher amounts of α-tocopherol and polyphenols were extracted from 2P olive pomace, while β-sitosterol, chlorophylls, and carotenoids were more concentrated in 3P olive pomace. Finally, tocopherol and pigment/polyphenol fractions exerted antioxidant activity in vitro and in accelerated oxidative conditions. These results highlight the potential of olive pomace to be upcycled by extracting from it, with green methods, functional phytocompounds for reuse in food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

In recent decades, food waste management has become a key priority of industrial and food companies, state authorities and consumers as well. The paper describes the biotechnological processing of mechanically deboned chicken meat (MDCM) by-product, rich in collagen, into gelatins. A factorial design at two levels was used to study three selected process conditions (enzyme conditioning time, gelatin extraction temperature and gelatin extraction time). The efficiency of the technological process of valorization of MDCM by-product into gelatins was evaluated by % conversion of the by-product into gelatins and some qualitative parameters of gelatins (gel strength, viscosity and ash content). Under optimal processing conditions (48–72 h of enzyme conditioning time, 73–78 °C gelatin extraction temperature and 100–150 min gelatin extraction time), MDCM by-product can be processed with 30–32% efficiency into gelatins with a gel strength of 140 Bloom, a viscosity of 2.5 mPa.s and an ash content of 5.0% (which can be reduced by deionization using ion-exchange resins). MDCM is a promising food by-product for valorization into gelatins, which have potential applications in food-, pharmaceutical- and cosmetic fields. The presented technology contributes not only to food sustainability but also to the model of a circular economy. [ABSTRACT FROM AUTHOR]

The effects of the drying process using the conventional oven and freeze-drying on the thermogravimetric profile, proximate composition, color parameters, individual bioactive compounds, and antioxidant activity in the grape residue (skin) were evaluated. Twenty individual phenolic compounds were identified, where a variation in concentration was observed for flavonols, stilbenes, phenolic acids, flavonoids, procyanidins, and particularly anthocyanins (malvidin-3,5-di-O-glucoside of 253.2–536.9 mg/kg) due to the drying process. Drying in a conventional oven caused a decrease of 23% of the total polyphenols. The skin of the BRS magna grape has a high concentration of total phenolic content of 489.5–148.3 mg.GAE/100 g, total anthocyanin content of 124.9–260.1 mg.CE/100 g, and total flavonoid content of 12.7–26.0 mg.QE/100 g. The results of free radical scavenging activity (1.26–4.91 μg/mL, as EC50) and ferric reducing antioxidant power (82.93–184.10 μmol/g of skin as equivalent to Fe2SO4) indicate high antioxidant activity, independently of the drying process applied. It was concluded that, if the application is directed to anthocyanin compounds, the use of lyophilization is recommended. On the other hand, if the interest is in bioactive compounds that exert antioxidant activity, conventional oven-drying can be used. [ABSTRACT FROM AUTHOR]

First-generation biofuel biorefineries may be a starting point for the development of new value chains, as their by-products and side streams retain nutrients and valuable molecules that may be recovered and valorized for high-value applications. This study provides a chemical characterization of post-fermentation corn oil and thin stillage, side streams of dry-grind corn bioethanol production, in view of their valorization. An overall long-term study was conducted on the two co-products collected over 1 year from a bioethanol plant. Water content, acid value, sedimentation, mineral composition, and fatty acid profiles were analyzed on post-fermentation corn oil. Results highlighted that its acid value was high (19.72–24.29 mg KOH/g), indicating high levels of free fatty acids, but stable over the year due to standardized operating conditions. The fatty acid profile was that typical of corn oil, with a prevalence of linoleic (54–59% of total fatty acids) over oleic (23–27%) and palmitic (12–17%) acids. Macronutrients, fatty acid, and mineral profiles were investigated in thin stillage. Results revealed the acidic pH (4.05–4.68) and high dilution (90–93% water) of this side stream. The dry mass was composed of fats (19–30%), proteins (8.8–12.8%), ash (8.7–9.5%), and fiber (7.3–9.8%). The concomitant presence of a variegate complex of molecules of nutritional interest in corn bioethanol co-products, with several potential high-value market applications, make the perspective of their recovery a promising strategy to create new cross-sector interconnections according to circular economy principles. [ABSTRACT FROM AUTHOR]

Walnut oilcake is a low-cost by-product of the edible oil industry but at the same time it is a valuable source of dietary fiber, natural antioxidants, and polyunsaturated fatty acids. In the context of health-friendly confectionary food products and to reduce the production cost, the aim of this study was to investigate the effect of walnut oilcake by-product on the quality characteristics and volatile profile of modified macarons. For this purpose, GC-MS and ITEX/GC-MS techniques were used to obtain the fatty acids methyl esters and the volatile profiles; physicochemical analyzes were performed to determine the nutritional characteristics and a nine-point hedonic scale test was performed for the sensory characteristics. The substitution of almond flour with 0%, 10%, 25% and 50% walnut oilcake powder increased the fiber, total phenolic content, and antioxidant capacity. Hedonic scores of the macaron samples made with different percentage of walnut oilcake decreased to additions of over 10%. Moreover, this result is emphasized by Pearson's correlation parameters indicating as optimal addition for modified macarons, percentages up to 10% of walnut oilcake. This approach could reduce the costs related to the acquisition of the ingredients due to the oilcake price which is 3% of the almonds flour price. [ABSTRACT FROM AUTHOR]

Sustainable utilization of agri-food wastes and by-products for producing value-added products (for cosmetic, pharmaceutical or food industrial applications) provides an opportunity for earning additional income for the dependent industrial sector. Besides, effective valorisation of wastes/by-products can efficiently help in reducing environmental stress by decreasing unwarranted pollution. The major focus of this review is to provide comprehensive information on valorisation of agri-food wastes and by-products with focus laid on bioactive compounds and bioactivity. The review covers the bioactives identified from wastes and by-products of plants (fruits, exotic fruits, vegetables and seeds), animals (dairy and meat) and marine (fish, shellfish seaweeds) resources. Further, insights on the present status and future challenges of sustainably utilizing agri-food wastes/by-products for value addition will be highlighted. [ABSTRACT FROM AUTHOR]

Every year, the poultry industry produces a large number of by-products such as chicken heads containing a considerable proportion of proteins, particularly collagen. To prepare gelatin is one of the possibilities to advantageously utilize these by-products as raw materials. The aim of the paper was to process chicken heads into gelatins. An innovative method for conditioning starting raw material was using the proteolytic enzyme. Three technological factors influencing the yield and properties of extracted gelatins were monitored including the amount of enzyme used in the conditioning of the raw material (0.4% and 1.6%), the time of the conditioning (18 and 48 h), and the first gelatin extraction time (1 and 4 h). The gelatin yield was between 20% and 36%. The gelatin gel strength ranged from 113 to 355 Bloom. The viscosity of the gelatin solution was determined between 1.4 and 9.5 mPa.s. The content of inorganic solids varied from 2.3% to 3.9% and the melting point of the gelatin gel was recorded between 34.5 and 42.2 °C. This study has shown that gelatin obtained from chicken heads has a promising potential with diverse possible applications in the food industry, pharmacy, and cosmetics. [ABSTRACT FROM AUTHOR]