Valorization and extraction optimization of Prunus seeds for food and functional food applications: A review with further perspectives

Extract toolkit for essential oils: State of the art, trends, and challenges

Plant essential oils have a wide range of applications including cosmetics, food, leather, and textiles. Traditional methods employed for essential oils extraction suffer from several drawbacks, which have escalated into a major bottleneck for industrial applications. To circumvent the limitations, various innovative and eco-friendly technologies have emerged for the extraction of essential oils, such as ultrasound-assisted extraction, pulsed electrical-assisted extraction, ohmic-assisted technology, supercritical fluid extraction, and solvent-free microwave extraction. These cutting-edge technologies provide notable advantages over traditional methods in terms of extraction efficiency, environmental safety, and product quality enhancement. This review highlights the advantage of these innovative techniques, with a particular focus on their ability to enhance the yield and antioxidant activity of essential oils while simultaneously reducing energy consumption. Additionally, the mechanisms of these new and eco-friendly extraction methods are thoroughly discussed. This review provides valuable insights into the advancements in essential oils extraction.

Unlocking the in vitro neuroprotection of sloe residues phenolic extracts by bioanalytical and chemometric strategies

Wild fruits, particularly the underutilized sloe (Prunus spinosa), are gaining interest as natural antioxidants, with residues from liqueur production being a source of bioactive compounds. This study proposes a sustainable approach for valorizing sloe residues, seeds and skins, by employing an innovative green extraction method. HPLC-ESI-QTOF and spectrophotometric techniques were used to explore the phenolic profile, highlighting the predominance of quercetin, 2,3-dihydroxybenzoic and ferulic acids (9.7-57 μg·g-1). In addition, the presence of Cu, Zn and Ca was confirmed by atomic absorption spectroscopy. Simultaneously, their neuroprotective potential against Alzheimer's disease (AD) was studied by exploring the inhibition of beta-amyloid aggregation and oxidative stress cytoprotection in SH-SY5Y cell line, standing out 1 μg·g-1 and 10 μg·g-1 extracts of sloe skin. Phenolic composition was correlated with bioactivities by means of multivariate analysis. These results contributed to highlight the potential of this bio-residue as a neuroprotective agent against AD in pharmaceutical and nutraceutical industries.

Nutraceuticals and dietary supplements: balancing out the pros and cons

While the market is full of different dietary supplements, in most countries, legislation is clear and strict towards these products, with severe limitations on their health claims. Overall, the claims cannot go beyond the consumption of a said supplement will contribute to a healthy diet. Thus, the supplement industry has been reacting and changing their approach to consumers. One change is the considerable growth of the nutraceutical market, which provides naturally produced products, with low processing and close to no claims on the label. The marketing of this industry shifts from claiming several benefits on the label (dietary supplements) to relying on the knowledge of consumers towards the benefits of minimally processed foods filled with natural products (nutraceuticals). This review focuses on the difference between these two products, their consumption patterns, forms of presentation, explaining what makes them different, their changes through time, and their most notable ingredients, basically balancing out their pros and cons.

The Potential of Plum Seed Residue: Unraveling the Effect of Processing on Phytochemical Composition and Bioactive Properties

Bioactive compounds extracted from plum seeds were identified and quantified, aiming to establish how the brandy manufacturing process affects the properties and possible cascade valorization of seed residues. Extraction with n-hexane using Soxhlet has provided oils rich in unsaturated fatty acids (92.24-92.51%), mainly oleic acid (72-75.56%), which is characterized by its heart-healthy properties. The fat extracts also contain tocopherols with antioxidant and anti-inflammatory properties. All the ethanol-water extracts of the defatted seeds contain neochlorogenic acid (90-368 µg·g-1), chlorogenic acid (36.1-117 µg·g-1), and protocatechuate (31.8-100 µg·g-1) that have an impact on bioactive properties such as antimicrobial and antioxidant. Anti-amyloidogenic activity (25 mg·mL-1) was observed in the after both fermentation and distillation extract, which may be related to high levels of caffeic acid (64 ± 10 µg·g-1). The principal component analysis showed that all plum seed oils could have potential applications in the food industry as edible oils or in the cosmetic industry as an active ingredient in anti-aging and anti-stain cosmetics, among others. Furthermore, defatted seeds, after both fermentation and distillation, showed the greatest applicability in the food and nutraceutical industry as a food supplement or as an additive in the design of active packaging.

Chemical Composition and Antibacterial and Antiulcerative Colitis Activities of Essential Oil from Pruni Semen

This study was sought to investigate the chemical composition and antibacterial and antiulcerative colitis (UC) effects of essential oil from Pruni Semen (PSEO). A GC-MS assay showed that the major compounds in PSEO were products of amygdalin hydrolysis, which possessed great antibacterial and anti-inflammatory potential. In vitro antibacterial experiments demonstrated that PSEO treatment inhibited activity of four kinds of intestinal pathogens probably by disrupting the cell wall. Further in vivo studies showed that PSEO administration significantly improved physiological indexes, attenuated histopathological characteristics, and inhibited proinflammatory cytokine production in dextran sulfate sodium (DSS)-induced UC mice. Network pharmacology and molecular docking results predicted that PSEO might prevent UC via regulating the PI3K/AKT pathway. Western blotting and immunofluorescence assays were further conducted for verification, and the results evidenced that PSEO intervention significantly regulated the PI3K/AKT pathway and the expression of its downstream proteins in DSS-induced mice. PSEO might provide a new dietary strategy for UC treatment.

Chemical and Biochemical Features of Spinasterol and Schottenol

Phytosterols, which are produced in plants, are structurally similar to cholesterol. Their basic structures consist of a cyclo pentano-perhydrophenanthrene nucleus composed of 3 hexane rings and of a pentane ring with an alkyl side chain. There are around more than 250 phytosterols and related compounds that have been identified in natural resources. Among them, spinasterol and schottenol, its dihydro analog, are often found in seeds, and consequently in seed oils, and in other botanical parts of some plant families such as Sapotaceae, Cactaceae, and Cucurbitaceae. Spinasterol and/or schottenol has been identified in dietary and cosmetic argan oil, milk thistle seed oil, nigella seed oil, and pumkin seed oil. These phytosterols that have several bioactive properties make them potentially attractive molecules in pharmacology. Their chemical and biochemical features are summarized and the analytical methods used to characterize and analyze these compounds are presented.

Valorization of Defatted Cherry Seed Residues from Liquor Processing by Matrix Solid-Phase Dispersion Extraction: A Sustainable Strategy for Production of Phenolic-Rich Extracts with Antioxidant Potential

The integrated valorization of food chain waste is one of the most promising alternatives in the transition to a sustainable bioeconomy. Thus, an efficient solid-phase matrix dispersion extraction method, using experimental factorial design and response surface methodology, has been developed and optimized for the recovery of polyphenols from defatted cherry seeds obtained after cherry liquor manufacture and subsequent fatty acid extraction, evaluating the effect of each processing step on the composition and phenolic content of sweet cherry residues. The phenolic extracts before fermentation showed the highest content of total polyphenols (TPC) and flavonoids (TFC) (3 ± 1 mg QE·g-1 and 1.37 ± 0.08 mg GAE·g-1, respectively), while the highest antioxidant capacity was obtained in the defatted seed extracts after both fermentation and distillation. In addition, high-performance liquid chromatography coupled to a quadrupole time-of-flight mass spectrometer (HPLC-ESI-QTOF-MS) was used to determine the phenolic profile. Dihydroxybenzoic acid, neochlorogenic acid, caffeic acid, and quercetin were the main phenolics found, showing differences in concentration between the stages of liquor production. The results underline the prospective of cherry by-products for obtaining phenol-rich bioactive extracts for possible use in different industrial sectors, offering a feasible solution for the cascade valorization of cherry agri-food waste.

Valorization of Prunus Seed Oils: Fatty Acids Composition and Oxidative Stability

Prunus fruit seeds are one of the main types of agri-food waste generated worldwide during the processing of fruits to produce jams, juices and preserves. To valorize this by-product, the aim of this work was the nutritional analysis of peach, apricot, plum and cherry seeds using the official AOAC methods, together with the extraction and characterization of the lipid profile of seed oils using GC-FID, as well as the measurement of the antioxidant activity and oxidative stability using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging method. Chemometric tools were required for data evaluation and the obtained results indicated that the main component of seeds were oils (30-38%, w). All seed oils were rich in oleic (C18:1n9c) and linoleic (C18:2n6c) acids and presented heart-healthy lipid indexes. Oil antioxidant activity was estimated in the range IC50 = 20-35 mg·mL-1, and high oxidative stability was observed for all evaluated oils during 1-22 storage days, with the plum seed oil being the most antioxidant and stable over time. Oxidative stability was also positively correlated with oleic acid content and negatively correlated with linoleic acid content. Therefore, this research showed that the four Prunus seed oils present interesting healthy characteristics for their use and potential application in the cosmetic and nutraceutical industries.

Essential Components from Plant Source Oils: A Review on Extraction, Detection, Identification, and Quantification

Oils derived from plant sources, mainly fixed oils from seeds and essential oil from other parts of the plant, are gaining interest as they are the rich source of beneficial compounds that possess potential applications in different industries due to their preventive and therapeutic actions. The essential oils are used in food, medicine, cosmetics, and agriculture industries as they possess antimicrobial, anticarcinogenic, anti-inflammatory and immunomodulatory properties. Plant based oils contain polyphenols, phytochemicals, and bioactive compounds which show high antioxidant activity. The extractions of these oils are a crucial step in terms of the yield and quality attributes of plant oils. This review paper outlines the different modern extraction techniques used for the extraction of different seed oils, including microwave-assisted extraction (MAE), pressurized liquid extraction (PLE), cold-pressed extraction (CPE), ultrasound-assisted extraction (UAE), supercritical-fluid extraction (SFE), enzyme-assisted extraction (EAE), and pulsed electric field-assisted extraction (PEF). For the identification and quantification of essential and bioactive compounds present in seed oils, different modern techniques-such as high-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared spectroscopy (FTIR), gas chromatography-infrared spectroscopy (GC-IR), atomic fluorescence spectroscopy (AFS), and electron microscopy (EM)-are highlighted in this review along with the beneficial effects of these essential components in different in vivo and in vitro studies and in different applications. The primary goal of this research article is to pique the attention of researchers towards the different sources, potential uses and applications of oils in different industries.

Thermal and Viscoelastic Responses of Selected Lignocellulosic Wastes: Similarities and Differences

Woody lignocellulosic biomasses comprise the non-edible parts of fruit trees. In recent years, the exploitation of this biomass has been widening in order to mitigate environmental issues. At the same time, this waste could be transformed into a value-added product (active carbon by pyrolysis, isolation of nanocellulose, oils or proteins). For either valorization path, a complete thermo-mechanical characterization is required. A detailed thermo-mechanical study (TGA, DSC, DMA) was performed on two types of lignocellulosic wastes, with and without kernels: on one side, the walnut shells (WS) and the pistachio shells (PsS) and, in the second category, the apricot seeds (AS), the date seeds (DS), and the plum seeds (PS). The results of the sample-controlled thermal analyses (HiRes TGA) evidenced a better resolution of the degradation steps of WS. Kinetic studies conducted also by conventional TGA (Flynn-Wall-Ozawa) and modulated TGA (MTGA) allowed us to make comparative reasonings concerning the degradation of the investigated biomasses. The DMA results revealed the effect of water traces and oil kernels on relaxation and supported the atypical DSC endotherm emphasized in the freezing temperature domain.

Apricot kernel characterization, oil extraction, and its utilization: a review

Apricot (Prunus armeniaca L.) kernels, one of the economical stone fruit kernels, are utilized worldwide for edible, cosmetic, and medicinal purposes. Oil from the apricot kernel is valued by the richness of unsaturated fatty acids, the high proportion of oleic acids, phenols, and tocopherol content. Oil yield with quality from apricot kernel varies with region, variety, and adopted method of oil extraction. This review discusses apricot kernel characterization, different conventional and novel methods of oil extraction, their merits and demerits as reported in the literature. Novel technologies such as microwave-assisted oil extraction, ultrasound-assisted oil extraction, enzyme-assisted oil extraction, and supercritical fluid oil extraction have emerged as the most promising extraction methods that allow efficient oil recovery in very environment-friendly ways. Knowledge of the extraction technique aids in giving higher oil recovery with minimal nutritional losses while retaining the original organoleptic properties.

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Investigating the Effect of Supercritical Carbon Dioxide Treatment on the Rheological, Thermal, and Functional Properties of Plum (Prunus domestica L.) Kernel Protein Isolates

Plum kernels are a promising source of dietary proteins that are irretrievably lost during processing. The recovery of these underexploited proteins could be eminently vital for human nutrition. Plum kernel protein isolate (PKPI) was prepared and exposed to a targeted supercritical carbon dioxide (SC-CO₂) treatment to diversify its effectiveness in industrial applications. The impacts of SC-CO₂ treatment at different processing temperatures (30-70 °C) on dynamic rheology, microstructure, thermal, and techno-functional characteristics of PKPI were investigated. The results revealed that the dynamic viscoelastic characteristics of SC-CO₂-treated PKPIs showed higher storage modulus, loss modulus, and lower tan δ value than native PKPI, indicating greater strength and elasticity of the gels. Microstructural analysis showed that the proteins experienced denaturation at elevated temperatures and resulted in the formation of soluble aggregates, which increased the heat requirement for thermal denaturation of SC-CO₂-treated samples. SC-CO₂-treated PKPIs demonstrated a decline of 20.74% and 30.5% in crystallite size and crystallinity. PKPIs treated at 60 °C showed the highest dispersibility, which was 1.15-fold higher than the native PKPI sample. SC-CO₂ treatment offers a novel path to improve the techno-functional properties of PKPIs and extend its use in food and non-food applications.

Food Wastes and Microalgae as Sources of Bioactive Compounds and Pigments in a Modern Biorefinery: A Review

The United Nations 2030 Agenda for Sustainable Development has created more pressure on countries and society at large for the development of alternative solutions for synthetic and fossil fuel derived products, thus mitigating climate change and environmental hazards. Food wastes and microalgae have been studied for decades as potential sources of several compounds that could be employed in various fields of application from pharmaceutical to textile and packaging. Although multiple research efforts have been put towards extracting rich compounds (i.e., phenolic compounds, tocopherols, and tocotrienols) from these sources, they still remain overlooked as two major sources of bioactive compounds and pigments, mainly due to inefficient extraction processes. Hence, there is a growing need for the development of optimized extraction methods while employing non-organic solvent options following the main principles of green chemistry. This review will focus on delivering a clear and deep analysis on the existing procedures for obtaining bioactive compounds and pigments from food wastes derived from the most consumed and produced fruit crops in the world such as apples, oranges, cherries, almonds, and mangoes, and microalgal biomass, while giving light to the existing drawbacks in need to be solved in order to take full advantage of the rich properties present in these two major biorefinery sources.