Phenolic profile of oils obtained from "horchata" by-products assisted by supercritical-CO2 and its relationship with antioxidant and lipid oxidation parameters: Triple TOF-LC-MS-MS characterization

Flavonoid Components, Distribution, and Biological Activities in Taxus: A review

Taxus, also known as "gold in plants" because of the famous agents with emphases on Taxol and Docetaxel, is a genus of the family Taxaceae, distributed almost around the world. The plants hold an important place in traditional medicine in China, and its products are used for treating treat dysuria, swelling and pain, diabetes, and irregular menstruation in women. In order to make a further study and better application of Taxus plants for the future, cited references from between 1958 and 2022 were collected from the Web of Science, the China National Knowledge Internet (CNKI), SciFinder, and Google Scholar, and the chemical structures, distribution, and bioactivity of flavonoids identified from Taxus samples were summed up in the research. So far, 59 flavonoids in total with different skeletons were identified from Taxus plants, presenting special characteristics of compound distribution. These compounds have been reported to display significant antibacterial, antiaging, anti-Alzheimer's, antidiabetes, anticancer, antidepressant, antileishmaniasis, anti-inflammatory, antinociceptive and antiallergic, antivirus, antilipase, neuronal protective, and hepatic-protective activities, as well as promotion of melanogenesis. Flavonoids represent a good example of the utilization of the Taxus species. In the future, further pharmacological and clinical experiments for flavonoids could be accomplished to promote the preparation of relative drugs.

Chemical Composition and Bioactive Antioxidants Obtained by Microwave-Assisted Extraction of Cyperus esculentus L. By-products: A Valorization Approach

Tiger nut is highly appreciated in the Mediterranean basin by the large number of nutritional advantages offered by a beverage, called "horchata," which is directly obtained from the tuber of Cyperus esculentus L. However, the current tiger nut harvesting and processing practices generate a large number of residues, mainly a solid by-product after processing and the plant that remains spread out in the fields. In this work the plant residues have been fully characterized to get a clear picture of the possibilities for its valorization to generate products with high added value. Several analytical techniques have been applied to obtain data to assess the real possibilities of these residues in advanced applications in the food, packaging and nutrition sectors. Results on the compositional and elemental analysis, monosaccharide composition, phenolic concentration, and antioxidant capacity were obtained from the dry powder (DP). The high content of α-cellulose (47.2 ± 1.8%) in DP could open new possibilities for these residues as raw material in the production of cellulose nanoentities. Many essential minerals with nutritional interest (Na, Mg, Ca, Mn, Fe, Cu, and Zn) and free sugars (xylose, arabinose, glucose, and galacturonic acid) were identified in the DP making it an interesting source of valuable nutrients. The total carbohydrate content was 171 ± 31 mg gdm -1. In addition, microwave-assisted extraction (MAE) was used to obtain extracts rich in polyphenolic compounds. A Box-Behnken design (BBD) was used, and the optimal extraction conditions predicted by the model were 80°C, 18 min, ethanol concentration 40% (v/v), and solvent volume 77 mL, showing an extraction yield of 2.27 ± 0.09%, TPC value was 136 ± 3 mg GAE 100 gdm -1 and antioxidant capacity by the ABTS method was 8.41 ± 0.09 μmol trolox gdm -1. Other assays (FRAP and DPPH) were also tested, confirming the high antioxidant capacity of DP extracts. Some polyphenols were identified and quantified: p-coumaric (7.67 ± 0.16 mg 100 gdm -1), ferulic (4.07 ± 0.01 mg 100 gdm -1), sinapinic (0.50 ± 0.01 mg 100 gdm -1) and cinnamic acids (1.10 ± 0.03 mg 100 gdm -1), 4-hydroxybenzaldehyde (1.28 ± 0.06 mg 100 gdm -1), luteolin (1.03 ± 0.01 mg 100 gdm -1), and naringenin (0.60 ± 0.01 mg 100 gdm -1). It can be concluded that C. esculentus L. residues obtained from the tiger nut harvesting and horchata processing could be an important source of high value compounds with potential uses in different industrial sectors, while limiting the environmental hazards associated with the current agricultural practices.

Tiger Nut (Cyperus esculentus L.): Nutrition, Processing, Function and Applications

The tiger nut is the tuber of Cyperus esculentus L., which is a high-quality wholesome crop that contains lipids, protein, starch, fiber, vitamins, minerals and bioactive factors. This article systematically reviewed the nutritional composition of tiger nuts; the processing methods for extracting oil, starch and other edible components; the physiochemical and functional characteristics; as well as their applications in food industry. Different extraction methods can affect functional and nutritional properties to a certain extent. At present, mechanical compression, alkaline methods and alkali extraction-acid precipitation are the most suitable methods for the production of its oil, starch and protein in the food industry, respectively. Based on traditional extraction methods, combination of innovative techniques aimed at yield and physiochemical characteristics is essential for the comprehensive utilization of nutrients. In addition, tiger nut has the radical scavenging ability, in vitro inhibition of lipid peroxidation, anti-inflammatory and anti-apoptotic effects and displays medical properties. It has been made to milk, snacks, beverages and gluten-free bread. Despite their ancient use for food and feed and the many years of intense research, tiger nuts and their components still deserve further exploitation on the functional properties, modifications and intensive processing to make them suitable for industrial production.

New Advances in the Phenolic Composition of Tiger Nut (Cyperus esculentus L.) by-Products

“Horchata” is a well-known Spanish beverage obtained from pressing tiger nuts. Its by-product is a potential source of sugar and fiber but also contains polyphenols; thus, it could be used as a new ingredient in the food industry. The aim of this work is to determine the phenolic compounds and compare the phenolic profile of two tiger nut by-products. A Box–Behnken design has been carried out to optimize the extraction of phenolic compounds from tiger nut by-products by ultrasound technology. The independent factors were time (min), ethanol/water (% v/v), and solvent/sample ratio (v/w). The model was validated and confirmed by ANOVA. A Protected Designation of Origin (PDO) of Valencia and a non-Protected Designation of Origin (n-PDO) tiger nut by-products were extracted under the optimal conditions and were characterized by HPLC-DAD-ESI-TOF-MS (High Performance Liquid Chropatography coupled to a photodiode array time-of-flight mass detector). Moreover, their antioxidant activities measured by three different methods (DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2′-Azinobis [3-ethylbenzothiazoline-6-sulfonic acid]-diammonium salt) and FRAP (ferric reducing antioxidant power)) were compared. A total of 45 polar compounds were identified, and the phenolic ones were quantified, some of them for the first time. PDO tiger nut by-product has been demonstrated to be richer in phenolic acids and other polyphenols and has higher antioxidant activity; meanwhile, n-PDO tiger nut by-product is richer in phenol precursors.

Plant Flavonoids: Chemical Characteristics and Biological Activity

In recent years, more attention has been paid to natural sources of antioxidants. Flavonoids are natural substances synthesized in several parts of plants that exhibit a high antioxidant capacity. They are a large family, presenting several classes based on their basic structure. Flavonoids have the ability to control the accumulation of reactive oxygen species (ROS) via scavenger ROS when they are formed. Therefore, these antioxidant compounds have an important role in plant stress tolerance and a high relevance in human health, mainly due to their anti-inflammatory and antimicrobial properties. In addition, flavonoids have several applications in the food industry as preservatives, pigments, and antioxidants, as well as in other industries such as cosmetics and pharmaceuticals. However, flavonoids application for industrial purposes implies extraction processes with high purity and quality. Several methodologies have been developed aimed at increasing flavonoid extraction yield and being environmentally friendly. This review presents the most abundant natural flavonoids, their structure and chemical characteristics, extraction methods, and biological activity.

Evaluation of antioxidant capacity, fatty acid profile, and bioactive compounds from buritirana (Mauritiella armata Mart.) oil: A little-explored native Brazilian fruit

Buritirana (Mauritiella armata Mart.) is a fruit species native to the Amazon and Cerrado region, belonging to the Arecaceae family. It has high nutritional and functional potential, yet little explored. In this study, we evaluated for the first time the overall yield, behavior of total carotenoids in the extraction kinetics, fatty acid profile, bioactive compounds, and the antioxidant capacity of the oil from buritirana fractions obtained by supercritical CO₂. The highest extraction yield was found in the pulp and whole without seed at 60 °C (18.06 ± 0.40 and 14.55 ± 1.10 g 100 g^-1 of the freeze-dried sample (fdw), respectively), and in the peel at 40 °C (8.31 ± 0.73 g 100 g^-1 fdw). During the extraction kinetics, the pulp had the highest yields of oil (41.57%) and total carotenoids (8.34 mg g^-1) after 61 min at 40 °C. The antioxidant potential, fatty acid profile, and α-tocopherol content were dependent on both fraction and temperature, with oleic acid being the main fatty acid. The oil from the whole fraction without seed had the largest number (20) of identified phenolic compounds. The extraction at 60 °C reduced the relative intensity of most compounds in the whole without seed and pulp. Moreover, it increased the intensity of the compounds in the peel. These results suggest that buritirana is a good oil source with great bioactive potential to produce new products with functional claims.

The Application of Supercritical Fluids Technology to Recover Healthy Valuable Compounds from Marine and Agricultural Food Processing By-Products: A Review

Food by-products contain a remarkable source of bioactive molecules with many benefits for humans; therefore, their exploitation can be an excellent opportunity for the food sector. Moreover, the revalorization of these by-products to produce value-added compounds is considered pivotal for sustainable growth based on a circular economy. Traditional extraction technologies have several drawbacks mainly related to the consumption of hazardous organic solvents, and the high temperatures maintained for long extraction periods which cause the degradation of thermolabile compounds as well as a low extraction efficiency of desired compounds. In this context, supercritical fluid extraction (SFE) has been explored as a suitable green technology for the recovery of a broad range of bioactive compounds from different types of agri-food wastes. This review describes the working principle and development of SFE technology to valorize by-products from different origin (marine, fruit, vegetable, nuts, and other plants). In addition, the potential effects of the extracted active substances on human health were also approached.

Antioxidant Properties of Soybean Oil Supplemented with Ginger and Turmeric Powders

Soybean oil has been supplemented with 10% (w/w) of ginger and turmeric powders derived from commercial products (GC—commercial ginger and TC—commercial turmeric), freeze-dried rhizomes (freeze-dried ginger (GR) and freeze-dried turmeric rhizome—TR) and peels (freeze-dried ginger peel (GP) and freeze-dried turmeric peel—TP) for developing a functional seasoning with great lipid stability for human consumption. The exhausted ginger and turmeric powders were also recovered and recycled two times to promote a more sustainable process. The antioxidant activity and oxidative stability of oil samples were evaluated respectively by spectrophotometric and Rancimat methods. Folin–Ciocalteu assay and HPLC analysis were also performed to quantify total polyphenols, ginger-derived 6-gingerol and 6-shogaol, and turmeric-derived curcumin. Their antioxidant activity as well as oxidative stability, which non-linearly decreased over cycles because of a strongly reduced phenolic extractability, linearly increased with increasing phenolic yields. Hence, ginger and turmeric can be proposed as healthy spices containing bioactive compounds to control lipid oxidation and improve oil stability. Moreover, the valorization of peels as eco-friendly source of natural antioxidants is a valid strategy for providing added-value to these agro-food wastes.

Fruits and fruit by-products as sources of bioactive compounds. Benefits and trends of lactic acid fermentation in the development of novel fruit-based functional beverages

Current awareness about the benefits of a balanced diet supports ongoing trends in humans towards a healthier diet. This review provides an overview of fruits and fruit-by products as sources of bioactive compounds and their extraction techniques, and the use of lactic acid fermentation of fruit juices to increase their functionality. Fruit matrices emerge as a technological alternative to be fermented by autochthonous or allochthonous lactic acid bacteria (LAB such as Lactiplantibacillus plantarum, Lacticaseibacillus rhamnosus, and other Lactobacillus species), and also as probiotic vehicles. During fermentation, microbial enzymes act on several fruit phytochemicals producing new derived compounds with impact on the aroma and the functionality of the fermented drinks. Moreover, fermentation significantly reduces the sugar content improving their nutritional value and extending the shelf-life of fruit-based beverages. The generation of new probiotic beverages as alternatives to consumers with intolerance to lactose or with vegan or vegetarian diets is promising for the worldwide functional food market. An updated overview on the current knowledge of the use of fruit matrices to be fermented by LAB and the interaction between strains and the fruit phytochemical compounds to generate new functional foods as well as their future perspectives in association with the application of nanotechnology techniques are presented in this review.

Pomegranate Peel as Suitable Source of High-Added Value Bioactives: Tailored Functionalized Meat Products

In the last few years, the consumer's concern with the relationship between health and diet has led to the search of foods with functional properties beyond the nutritional. In this framework, the consumption of pomegranate has increased due to their sensorial attributes and remarkable amounts of bioactive compounds, which generate, at the same time, huge amounts of by-products. A search in the Scopus database for the last 10 years has revealed the rising interest in pomegranate peel (PP), the main residue from this fruit. The meat industry is a food sector that has had to search for new alternatives to substitute the use of synthetic preservatives by new natural additives, to extend the self-life and keep the quality attributes of their processed products. This review sets out the main bioactivities of PP extracts, and their incorporation in meat products is elaborated. PP is a good source of bioactive compounds, including phenolic acids, flavonoids and hydrolyzable tannins, which have beneficial health effects. It can be concluded that the reformulation of meat products with PP extracts is a suitable strategy for enhancing their technological characteristics, in addition to conferring functional properties that make them healthier and potentially more acceptable for the consumer.

Recent advances and comparisons of conventional and alternative extraction techniques of phenolic compounds

Phenolic compounds are a group of secondary metabolites produced by plants under stressful conditions. Phenolic compounds play an important role in the prevention and treatment of certain illnesses and are exploited by the food and pharmaceutical industries. Conventional methods are commonly used as models to compare the efficiencies of alternative extraction methods. Among alternative extraction processes, microwave-assisted extraction (MAE), pressurized liquid extraction (PLE), supercritical fluid extraction (SFE) and ultrasonic-assisted extraction (UAE) are the most studied. These methods produce extracts rich in phenolic compounds using moderate temperatures, short extraction times, and solvents generally recognized as safe. The combination of extraction time and temperature plays a critical role in the stability of the compounds. Solvents of higher polarity enhance the extraction of phenolic compounds. The use of the ethanol-water mixture for MAE, PLE, and UAE is recommended. MAE and UAE involve shorter extraction times than do PLE and SFE. SFE requires a low average temperature (40 °C). MAE produces the highest total phenolic content [227.63 mg GAE/g dry basis (d.b.)], followed by PLE (173.65 mg GAE/g d.b.), UAE (92.99 mg GAE/g d.b.) and SFE (37 mg GAE/g d.b.). Extraction yields and recovery rates of the phenolic compounds can be enhanced by combining and integrating extraction methods.

Physicochemical Characterization, Antioxidant Activity, and Phenolic Compounds of Hawthorn (Crataegus spp.) Fruits Species for Potential Use in Food Applications

Hawthorn belongs to the Crataegus genus of the Rosaceae family and is an important medicinal plant. Due to its beneficial effects on the cardiovascular system and its antioxidant and antimicrobial activity hawthorn has recently become quite a popular herbal medicine in phytotherapy and food applications. In this study, physicochemical characterization (color parameters, pH, titratable acidity, total soluble solids, soluble carbohydrate, total carotenoid, total phenols, and flavonoid contents), antioxidant activity (by ferric-reducing antioxidant power, FRAP assay), and quantification of some individual phenolic compounds of fruits of 15 samples of different hawthorn species (Crataegus spp.) collected from different regions of Iran were investigated. According to findings, the total phenols, total flavonoid content, and antioxidant activity were in the range of 21.19–69.12 mg gallic acid equivalent (GAE)/g dry weight (dw), 2.44–6.08 mg quercetin equivalent (QUE)/g dw and 0.32–1.84 mmol Fe⁺⁺/g dw, respectively. Hyperoside (0.87–2.94 mg/g dw), chlorogenic acid (0.06–1.16 mg/g dw), and isoquercetin (0.24–1.59 mg/g dw) were found to be the most abundant phenolic compounds in the extracts of hawthorn fruits. The considerable variations in the antioxidant activity and phenolic compounds of hawthorn species were demonstrated by our results. Hence, the evaluation of hawthorn genetic resources could supply precious data for screening genotypes with high bioactive contents for producing natural antioxidants and other phytochemical compounds valuable for food and pharma industries.

Effect of Different Green Extraction Methods and Solvents on Bioactive Components of Chamomile (Matricaria chamomilla L.) Flowers

Chamomile (Matricaria chamomilla L.) dried flowers contain a group of interesting biologically active compounds such as sesquiterpenes, flavonoids, coumarins, vitamins, phenolic acids and glucosides. Therefore, the aim of the present study was to characterize the composition in bioactive compounds (specialized metabolites) present in water and ethanol extracts of chamomile flowers, together with monitoring the impact of different extraction techniques (conventional vs. ultrasound-assisted extraction (UAE)) on the parameters under investigation. UAE treatment significantly decreased the extraction time of bioactive compounds from herbal material. Polyphenolic compounds content and antioxidant capacity were significantly higher in UAE extracts. Moreover, solvent type had a significant impact on the specialized metabolites content, while the highest vitamin C and polyphenols content were recorded in 50% ethanol (v/v) extracts. Optimization of basic extraction factors: solvent type, temperature and technique is crucial for obtaining the extracts with the highest content of specialized metabolites and antioxidant capacity.

Ethnopharmacology, phytochemistry and biological activity of Erodium species: A review

Erodium spp. is a genus that can be found in all continents that has been traditionally used in folk medicine to treat many diseases such as hemorrhage, dermatological disorders, indigestion, and inflammatory diseases. Moreover, Erodium leaves have been used for the preparation of salads, omelets, sandwiches, sauces and soups, among other food products. The objective of this review was to show the recent and relevant studies about extraction of bioactive compounds, the phytochemical characterization, the potential biological activities and toxicological evidence reported in both in vitro and in vivo studies from Erodium spp. In addition, the use of Erodium spp. as natural compounds against the development of diseases were also showed. This review highlights the traditional use of Erodium species in several countries as a therapeutic agent to treat several diseases (such as constipation, dermatological disorders, diabetes, indigestion, urinary inflammations, and as carminative agent), the factors influencing the extraction of bioactive compounds (mainly species and solvent composition on phenolic compounds) and phytochemical profile (presence of essential oils and alkaloids), the scientific evidence about its anti-inflammatory, antimicrobial (against both spoilage and pathogenic microorganisms), antiviral and other health-related activities (anti-protozoal and anti-viral activity) as well as the toxicological evidence. Erodium spp. is a relevant source of compounds with antioxidant, antimicrobial, and biological activity, which support its potential exploration in pharmacological and food area. Major efforts are necessary to advance the knowledge about Erodium genus regarding the relation between traditional use and scientific evidence, optimization of extraction conditions, the influence on biological mechanisms at animal and clinical levels, and bioaccessibility and bioavailability of bioactive compounds.

Influence of Temperature, Solvent and pH on the Selective Extraction of Phenolic Compounds from Tiger Nuts by-Products: Triple-TOF-LC-MS-MS Characterization

The aim of this study was to assess the effect of temperature, solvent (hydroethanolic mixtures) and pH on the recovery of individual phenolic compounds from "horchata" by-products. These parameters were optimized by response surface methodology and triple-TOF-LC-MS-MS was selected as the analytical tool to identify and quantify the individual compounds. The optimum extraction conditions were 50% ethanol, 35 °C and pH 2.5, which resulted in values of 222.6 mg gallic acid equivalents (GAE)/100 g dry matter and 1948.1 µM trolox equivalent (TE)/g of dry matter for total phenolic content (TPC) and trolox equivalent antioxidant capacity (TEAC), respectively. The extraction of phenolic compounds by the conventional solvent method with agitation was influenced by temperature (p = 0.0073), and more strongly, by the content of ethanol in the extraction solution (p = 0.0007) while the pH did not show a great impact (p = 0.7961). On the other hand, the extraction of phenolic acids was affected by temperature (p = 0.0003) and by ethanol amount (p < 0.0001) but not by the pH values (p = 0.53). In addition, the percentage of ethanol influenced notably the extraction of both 4-vinylphenol (p = 0.0002) and the hydroxycinnamic acids (p = 0.0039). Finally, the main individual phenolic extracted with hydroethanolic mixtures was 4-vinylphenol (303.3 μg/kg DW) followed by spinacetin3-O-glucosyl-(1→6)-glucoside (86.2 μg/kg DW) and sinensetin (77.8 μg/kg DW).

Nutritional and Microbiological Quality of Tiger Nut Tubers (Cyperus esculentus), Derived Plant-Based and Lactic Fermented Beverages

Tiger nut (Cyperus esculentus) is a tuber that can be consumed raw or processed into beverages. Its nutritional composition shows a high content of lipid and dietary fiber, close to those of nuts, and a high content of starch, like in other tubers. Tiger nuts also contain high levels of phosphorus, calcium, and phenolic compounds, which contribute to their antioxidant activity. From those characteristics, tiger nuts and derived beverages are particularly relevant to limit food insecurity in regions where the plant can grow. In Europe and United States, the tiger nut derived beverages are of high interest as alternatives to milk and for gluten-free diets. Fermentation or addition of probiotic cultures to tiger nut beverages has proven the ability of lactic acid bacteria to acidify the beverages. Preliminary sensory assays concluded that acceptable products are obtained. In the absence of pasteurization, the safety of tiger nut-based beverages is not warranted. In spite of fermentation, some foodborne pathogens or mycotoxigenic fungi have been observed in fermented beverages. Further studies are required to select a tailored bacterial cocktail which would effectively dominate endogenous flora, preserve bioactive compounds and result in a well-accepted beverage.