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BACKGROUND: Owing to their health benefits, walnuts are attracting interest as a good option for nutritious meals, thereby promoting their production. Furthermore, the adoption of ecologically and environmentally friendly agriculture strengthens biostimulant use as a sustainable complement to traditional fertilizers. This study evaluated the effects of different foliar‐applied biostimulants in walnut tree orchards, in northeastern Portugal, on walnuts' chemical composition and bioactivity. RESULTS: Walnut samples were rich in fat (particularly the polyunsaturated linoleic acid), dietary fiber and protein. Sucrose was the most prevalent soluble sugar, followed by glucose and fructose. Studied samples also showed an antioxidant activity comparable (or superior) to that of Trolox. Some plant biostimulants (e.g. Sprint Plus®) had a positive impact on the nutritional composition of walnuts, more specifically by boosting tocopherol levels, besides improving the bioactivity of walnut extracts against specific bacteria. CONCLUSION: Overall, this research demonstrated that important quality traits of walnuts can be improved using sustainable agricultural bioproducts and practices. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Mangroves store significant amounts of carbon in both sediment and water. Methane (CH4) is often produced in anoxic, organic‐rich sediments during carbon degradation and released to overlying waters via porewater exchange. Yet, a portion of CH4 can be oxidized to CO2 before emission. Here, we investigate whether CH4 oxidation impacts its emissions using high‐temporal resolution CH4 concentration and stable isotope (δ13C‐CH4) observations collected over 14 tidal cycles in 2 Brazilian mangrove creeks with no river inputs. We found higher CH4 concentrations (~ 150 nM) more depleted in 13C (−75‰) during low tide than high tide at both creeks. Similar δ13C‐CH4 values between low tide surface waters and porewaters further suggest tidally driven porewater exchange as the main source of CH4. More 13C‐enriched CH4 in surface waters and surface sediments than deep sediments indicate partial CH4 oxidation prior to exchange with the atmosphere. A stable isotope mass balance revealed that 17–58% of CH4 was oxidized at rates of 3–25 μmol m−2 d−1 in the water column of tidal creeks. A larger portion of deep porewater CH4 (45–61%) was oxidized in sediments prior to porewater exchange with surface creek waters. The two mangrove creeks had average water–air CH4 fluxes of 51–109 μmol m−2 d−1 over spring‐neap tidal cycles. These aquatic CH4 emissions offset only < 3% of the mangroves' soil carbon sequestration. Overall, CH4 oxidation in both surface water and sediment attenuated CH4 emissions to the atmosphere. [ABSTRACT FROM AUTHOR]

Mangrove‐dominated coastlines have high carbon sequestration capacity, but it remains unclear whether tidally outwelled carbon is transformed within the coastal ocean or exported offshore. Here, we used radium isotopes (224Ra and 223Ra) to investigate carbon outwelling in two mangrove seascapes in Brazil across multiple spatial scales. We sampled porewaters to define the source composition, mangrove creek waters to resolve tidal cycles, and cross‐shelf transects to trace outwelling in coastal seascapes. Radium isotopes were positively correlated with dissolved inorganic (DIC), organic (DOC) and particulate organic (POC) carbon across the seascapes. DIC was the primary form of carbon (mean ± SD), representing 85% of the total carbon pool as bicarbonate (75 ± 11%), carbonate (6 ± 5%), and CO2 (4 ± 9%). DOC and POC accounted for 10 ± 6% and 5 ± 6% of total carbon, respectively. Although mangrove waters emitted CO2 to the atmosphere (38–143 mmol m−2 d−1), both bays and continental shelves were a CO2 sink (−2.5 to −0.5 mmol m−2 d−1) associated to chlorophyll‐a enrichments (r2 = 0.86). Total carbon outwelled from mangroves were 3–4 times higher than soil carbon burial at both mangrove sites. Bicarbonate export (27–72 mmol m−2 d−1) to the continental shelf was the major fate of carbon outwelling, more than doubling the perceived capacity of mangrove soil to sequester carbon. Hence, disregarding outwelling as a blue carbon sink mechanism would lead to underestimated assessments of how mangroves capture CO2 and help to mitigate climate change. Plain Language Summary: Mangrove forests effectively store large amounts of carbon within their muddy soils due to their complex root systems, high sedimentation rates, and high productivity. Mangroves also play a crucial role in exporting carbon to the ocean through tidal flushing and climate change mitigation. Here, we measured overlooked lateral carbon fluxes using geochemical tracers. Our findings demonstrated that mangroves could sequester 3–4 times more CO2 if total carbon exports to ocean are accounted in addition to soil carbon burial. Most of the carbon is exported as bicarbonate, with the potential to remain in seawater for millennia. We argue that a fraction of mangrove carbon is not lost during transport offshore, but rather stored in the ocean, the largest global carbon reservoir. Key Points: Porewater exchange is a pivotal component of the carbon budget within mangrove seascapesMangrove carbon outwelling oscillates between tidal cycles and reaches the continental shelf within 1–3 weeksCarbon sequestration via outwelling to the ocean was 3–4 times greater than soil burial [ABSTRACT FROM AUTHOR]

Submarine groundwater discharge (SGD) dynamically links land‐ and ocean‐derived chemical constituents, such as metals, in the coastal ocean. While many metals are sediment‐bound, changing environmental conditions, particularly along the coast, may lead to increased release of metals to their dissolved and more bioavailable form. Here, we review metal behavior, speciation, and drivers of mobilization in the coastal environment under anthropogenic influence. We also model global metal contamination risk to the coastal ocean via SGD considering anthropogenic and hydrogeologic pressures, where tropical regions with high population density, SGD, and acid sulfate soils (4% of the global coast) present the highest risk. Although most SGD studies focus on other analytes, such as nutrients, this review demonstrates the importance of considering SGD as a critical pathway for metals to reach the coastal ocean under rapidly changing environmental conditions. [ABSTRACT FROM AUTHOR]

The current global food system must adapt to the expected growth of world population (about 9 billion individuals by 2050). This adaptation will probably include an increased consumption of edible wild foods, due to their richness in micronutrients and bioactive compounds, besides providing a cost-effective and sustainable way of improving caloric food security. A striking example of such natural matrices is the Quercus genus, which has the additional advantage of being widespread throughout the Northern Hemisphere. In a traditional sense, Quercus fruits (acorns) were mainly used in animal feeding, despite their potentially important role on the rural economy. But this preconception is changing. In fact, their nutritional value, high contents in phytochemical compounds, biological activity (such as antioxidant, anticarcinogenic, and cardioprotective properties) and use in the treatment of specific diseases (such as atherosclerosis, diabetes, or Alzheimer's disease) have raised the interest in integrating acorns into the human diet. Accordingly, this comprehensive overview was designed to provide an evidence-based review of the literature, with the objective to achieve useful conclusions regarding the nutritional properties, methodologies of extraction, identification, and characterization of a wide variety of bioactive compounds and scientifically validated bioactivities in Quercus species worldwide. The industrial by-products from acorn oil extraction or flour production are also included. Data regarding the analytical techniques, individual compounds, and their bioactivities, are organized in tables. The reported data are discussed and directions for further investigations are suggested, highlighting the use of acorns in food, nutraceutical, and pharmaceutical applications. [ABSTRACT FROM AUTHOR]

'Serra da Estrela' cheese is a Portuguese delicacy, which has been produced for centuries from the milk of cattle pasturing in the protected Serra da Estrela natural park. Transforming this cheese into a functional food would be a huge benefit for the market and the consumer. Decocted extracts, dried chestnut flowers and lemon balm plants were incorporated into the cheese to functionalise it, granting antioxidant activity to this foodstuff. The functionalised cheeses showed higher antioxidant activity, especially lipid peroxidation inhibition. The incorporation of dried plants appeared to be more effective than using decoctions, but the influence of the plant species was less observable. Furthermore, the fatty acids profile of the cheeses was also determined through gas chromatography. C18:1 and C16:0 were the most abundant fatty acids; saturated fatty acids prevailed over the unsaturated ones. Between the control and the incorporated samples no significant differences were found. In addition, the external colour was measured through a spectrophotometer for lightness, yellowness and redness. There were some differences recorded for each samples' colour. In general, the results indicated that the functionalisation of this exquisite dairy product with natural plant extracts provided beneficial characteristics, both for consumers (healthier product) and producers (added-value products). Practical applications The food industry is always searching for new products which are cheaper to produce and healthier for the consumer, withstanding longer storage periods. 'Serra da Estrela' cheese was incorporated with chestnut flowers and lemon balm dried plants and their respective decoctions in order to achieve antioxidant properties. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction Analytical methods used in phytochemistry analysis are limited by the sample preparation step, which should ideally be fast, accurate, ecofriendly and achievable using low quantities of the sample. Matrix solid-phase dispersion (MSPD) may be a good alternative for combining extraction and purification procedures, thereby reducing the indicated limitations. Objective Applying an MSPD extraction procedure coupled to high-performance liquid chromatography diode-array detection (HPLC/DAD) as an alternative methodology to evaluate isoflavone profiles. Methods Isoflavone profiles were determined for the leaves of nine species of Medicago in the late flower phenological stage (one or more nodes with 50% open flowers, no seed pods). Extraction was performed following MSPD, and isoflavone profiles were characterised using HPLC/DAD. The quantified amounts were compared with previous results in different species commonly recognised as good sources of isoflavones. Results Formononetin was the major isoflavone in most species, except M. polymorpha and M. truncatula. The isoflavone amounts were significantly different among the assayed species, with M. orbicularis and M. arabica as the major isoflavone sources, while M. rigidula presented the lowest contents. Furthermore, the detected differences allow electing the best species as a primary source of a specific isoflavone. Conclusion The MSPD allowed good extraction efficiency, reproducibility and recovery. Some of the species showed relevant isoflavone contents, even when compared with acknowledged plant sources such as soy or red clover. To the best of our knowledge the results presented are reported for the first time in these species. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Natural matrices are important sources of new antitumor and antimicrobial compounds. Species such as Laurus nobilis L. (laurel) might be used for this purpose, considering its medicinal properties. Herein, in vitro activity against human tumor cell lines, bacteria, and fungi was evaluated in enriched phenolic extracts. Specifically, methanol and aqueous extracts of wild and cultivated samples of L. nobilis were compared considering different phenolic groups. Principal component analysis (PCA) was applied to understand how each extract acts differentially against specific bacteria, fungi, and selected human tumor cell lines. In general, the extract type induced the highest differences in bioactivity of laurel samples.However, fromthe PCA biplot, it became clear that wild laurel samples were higher inhibitors of tumor cell lines (HeLa, MCF7, NCI-H460, and HCT15). HepG2 had the same response to laurel from wild and cultivated origin. It was also observed that methanolic extracts tended to have higher antimicrobial activity, except against A. niger, A. fumigatus, and P. verrucosum. The differences in bioactivity might be related to the higher phenolic contents in methanolic extracts. These results allow selecting the extract type and/or origin with highest antibacterial, antifungal, and antitumor activity. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyse the lipid peroxidation inhibition in beef burgers after incorporation of Boletus edulis extracts at different concentrations. Beef burger samples were stored for 8 days, and chemical and nutritional parameters, including the free fatty acid profile, were evaluated. Furthermore, the inhibition of thiobarbituric acid reactive substances (TBARS) formation, free radical scavenging activity and reducing power were determined. Polyunsaturated fatty acids, mainly arachidonic (C20:4n6) and cis-5,8,11,14,17-eicosapentaenoic (C20:5n3) acids were protected in the presence of mushroom extract. The antioxidant potential increased in beef burgers supplemented with mushroom extract, giving higher radical scavenging properties, reducing power and TBARS inhibition capacity. These findings indicated that beef burger patties were protected from lipid peroxidation in the presence of mushroom extract. [ABSTRACT FROM AUTHOR]

In order to determine the optimum operational conditions for phenols extraction, a series of assays were performed in the Guara variety of almond (Prunus dulcis ). Four variable operational conditions factors were considered: solvent type, solvent volume, temperature and extraction time. Phenols extracts antioxidant properties were evaluated, either chemically, by screening the free radical scavenging activity, or biochemically, by measuring the inhibition of thiobarbituric acid reactive substances formation in brain cells used as model for the study of lipid peroxidation damage in biomembranes. The extraction of the totality of phenols, confirmed by their antioxidant properties, allows the calculation of ideal doses for almond intake concerning antioxidant effects. The best outcome, regarding these proposals was obtained in the following conditions: 50 mL of methanol with 60 min of extraction time at 25C. PRACTICAL APPLICATIONS The quantification of total phenols in the extracts allows the definition of the most adequate doses of almond to be included in healthy diets in order to obtain the best antioxidant effects. This is quite important as it is not yet well defined if the over-intake of these compounds can cause deleterious effects. The correlations obtained between phenols and antioxidant activity allows an estimation of extract concentration providing 50% inhibition values instead of their experimental determination. In future works with the same or other varieties we can achieve antioxidant activity parameters through phenols determination. From an industrial point of view, the obtained results offer a possibility to valorise almond as a better food product obtained from an economical natural resource. Furthermore, almond tree could be cultivated more intensively, namely in areas with little agricultural potential, as it represents a culture with modest needs in terms of practical management. [ABSTRACT FROM AUTHOR]