Optimized Camellia sinensis var. sinensis, Ilex paraguariensis, and Aspalathus linearis blend presents high antioxidant and antiproliferative activities in a beverage model

Anthocyanin-rich extract from purple tea: Chemical stability, cellular antioxidant activity, and protection of human erythrocytes and plasma

This study aimed to obtain an anthocyanin extract from the purple leaves of Camellia sinensis cv. Zijuan using a sustainable, non-toxic, and low-cost solid-liquid extraction, employing an aqueous citric acid solution (0.2 mol/L) as the extracting solvent, and to evaluate its chemical stability at different pH values, as well as its in vitro antioxidant properties in chemical and biological terms. The phenolic composition, in vitro antioxidant activity, and the stability of anthocyanins against pH, temperature, and light of the crude extract (CE) were evaluated, as well as the phenolic composition and bioactivity in the crude lyophilised extract (CLE). In the direct/reverse spectrophotometric titration, anthocyanins showed structural changes between pH 2 and 10, and reversibility of 80%. The antioxidant activity against the DPPH radical showed inhibition percentages of 73% (pH 4.5) to 39% (pH 10). Thermal stability was observed at 60 °C, and prolonged exposure of the extract to light caused photodegradation of the anthocyanins. Thirty-three phenolic compounds, including anthocyanins and catechins, were quantified in the CLE by UPLC-ESI-MS and HPLC, totalling 40.18 mg/g. CLE reduced cell viability (IC50 from 18.1 to 52.5 μg GAE/mL), exerted antiproliferative (GI50 from 0.0006 to 17.0 μg GAE/mL) and cytotoxic (LC50 from 33.2 to 89.9 μg GAE/mL) effects against A549 (human lung adenocarcinoma epithelial cells), HepG2 (hepatocellular carcinoma), HCT8 (ileocecal colorectal adenocarcinoma), and Eahy926 (somatic cell hybrid cells); and showed protection against oxidation of human plasma (635 ± 30 mg AAE/g). The results showed the diversity of compounds in the extracts and their potential for technological applications; however, temperature, pH, and light must be considered to avoid diminishing their bioactivity.

Conceptual functional-by-design optimisation of the antioxidant capacity of trans-resveratrol, quercetin, and chlorogenic acid: Application in a functional tea

Designing functional foods as delivery systemsmay become a tailored strategy to decrease the risk of noncommunicable diseases. Therefore, this work aims to optimise a combination of t-resveratrol (RES), chlorogenic acid (CHA), and quercetin (QUE) based on antioxidant assays and develop a functional tea formulation enriched with the optimal polyphenol combination (OPM). Experimental results showed that the antioxidant capacity of these compounds is assay- and compound-dependent. A mixture containing 73% RES and 27% QUE maximised the hydroxyl radical scavenging activity and FRAP. OPM upregulated the gene expressions of heme oxygenase-1, superoxide dismutase, and catalase and decreased the reactive oxygen species generation in L929 fibroblasts. Adding OPM (100 mg/L)to a chamomile tea increased FRAP:39%, DPPH:59%; total phenolic content: 57%, iron reducing capacity: 41%, human plasma protection against oxidation: 67%. However, pasteurisation (63 °C/30 min) decreased onlythe DPPH. Combining technology, engineering, and cell biology was effective for functional tea design.

Sustainable and effective approach to recover antioxidant compounds from purple tea (Camellia sinensis var. assamica cv. Zijuan) leaves

Camellia sinensis var. assamica cv. Zijuan (purple tea) is known for its content of anthocyanins, flavan-3-ols, and bioactivities. This study aimed to verify the influence of solvent polarity, in a solid-liquid extraction, on the content of phenolic compounds and chlorophylls, instrumental color, and antioxidant activity. Different proportions of water and ethanol (0:100, 25:75, 50:50, 75:25, and 100:0 v/v) were used for extraction. The results showed that the hydroalcoholic extract (75 % ethanol + 25 % water) had the highest contents of total flavonoids, total anthocyanins, chlorophyll A, and total carotenoids, as well as presenting the highest color intensity, proportion of yellow pigments, and antioxidant activity (total reducing capacity and scavenging of the DPPH free radical). Twenty-two compounds were identified, with chlorogenic acid, hesperidin, (-)-epicatechin, (-)-epigallocatechin gallate, and isoquercitrin being the main phenolics. This phenolic-rich extract inhibited lipoperoxidation induced in egg yolk homogenate (IC₅₀ = 455 mg/L), showed no hemolytic behavior when human erythrocytes were subjected to osmotic stress, and exerted in vitro cytotoxic effects against cancer and hybrid cells. The extract obtained with the mixture of non-toxic solvents presented critical bioactivities, as well as a comprehensive identification of phenolic compounds in the cultivar, and has potential to be used in technological applications.

Contribution of the diverse experimental models to unravelling the biological scope of dietary (poly)phenols

The health benefits associated with (poly)phenols need to be supported by robust and insightful information on their biological effects. The use of in vitro, ex vivo, and in vivo models is crucial to demonstrate functionalities in specific targets. In this regard, bioaccessibility, bioavailability, and tissue/organ distribution need to be fully understood and established. In addition, the structure-function relationships, concerning both descriptive and mechanistic information, between specific compounds and therapeutic objectives, need to be supported by results obtained from in vivo studies. Nevertheless, these studies are not always possible or have some limitations, particularly concerning the mechanistic information explaining the health benefits provided that should be covered with complementary experimental models. Based on these premises, this review aims to overview the contribution of the separate experimental approaches to gain insights into the bioaccessibility, bioavailability, and bioactivity of (poly)phenols. To achieve this objective, recent evidence available on the linkage of healthy/functional foods with the incidence of non-communicable pathologies is presented. The different experimental approaches provide complementary information that allows advances to be applied to the knowledge gained on the functional properties and mechanistic facts responsible for the health attributions of polyphenols. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Deferoxamine Supplementation Abolished Iron-Related Toxicity of Ilex paraguariensis Extract: Behavioral and Biochemical Evaluation in Adult Zebrafish (Danio rerio)

Ilex paraguariensis (Herb mate) is a native plant from South America, widely consumed through the infusion of dried leaves. The presence of antioxidant properties in herb mate may be relevant and contribute to evaluating the effect of its compounds against oxidative stress, which could cause neurodegenerative diseases. Despite having health benefits, there are reports of the presence of heavy metals in extracts obtained from the infusion. One of these metals is iron (Fe), found in large amounts in herb mate. To reverse the cumulative effects of metals and Fe in the body, the use of Deferoxamine (Dfx) is indicated, being a potent chelator of Fe. In this work, we aimed to evaluate the antioxidant potential of the micro-encapsulated extract of I. paraguariensis (MEIP) supplemented with Dfx on zebrafish behavior and biochemical biomarkers. To evaluate the effect per se and the supplementation, four groups were established: the first group was the control (water); the second, fish treated with MEIP; the third group was formed of fish treated with Dfx; while the fourth group was treated with both MEIP and Dfx. When applied alone, Dfx presents an anxiogenic-like pattern on zebrafish (Danio rerio), while the MEIP shows an anxiolytic-like behavior. The antioxidant enzymes are re-modulated close to control when the MEIP + Dfx is applied. The cholinergic system shows an activation of the signaling, as well as the heme radical group formation, which is not affected by the Dfx-chelating effect. Thus, the supplementation of MEIP with Dfx is important to transform this extract into one that is safer and healthier for human consumption.

From the forest to the plate - Hemicelluloses, galactoglucomannan, glucuronoxylan, and phenolic-rich extracts from unconventional sources as functional food ingredients

This study aimed to characterise pressurised hot water (PHW) extracts from nonconventional sources of functional carbohydrates and phenolic compounds in terms of antioxidant capacity, antiviral activity, toxicity, and human erythrocytes' protection antidiabetic potential. PHW extracts of Norway spruce bark (E1 + E2) and Birch sawdust (E3 + E4) contained mostly galactoglucomannan and glucuronoxylan. In contrast, samples E5 to E9 PHW extracted from Norway spruce, and Scots pine bark are rich sources of phenolic compounds. Overall, phenolic-rich extracts presented the highest inhibition of α-amylase and α-glucosidase and protection against stable non-enveloped enteroviruses. Additionally, all extracts protected human erythrocytes from hemolysis. Cell-based experiments using human cell lines (IMR90 and A549) showed extracts' non-toxicin vitroprofile. Considering the relative toxicological safety of extracts from these unconventional sources, functional carbohydrates and polyphenol-rich extracts can be obtained and further used in food models.

Hibiscus, Rooibos, and Yerba Mate for Healthy Aging: A Review on the Attenuation of In Vitro and In Vivo Markers Related to Oxidative Stress, Glycoxidation, and Neurodegeneration

The world is currently undergoing a demographic change towards an increasing number of elderly citizens. Aging is characterized by a temporal decline in physiological capacity, and oxidative stress is a hallmark of aging and age-related disorders. Such an oxidative state is linked to a decrease in the effective mechanisms of cellular repair, the incidence of post-translational protein glycation, mitochondrial dysfunction, and neurodegeneration, just to name some of the markers contributing to the establishment of age-related reduction-oxidation, or redox, imbalance. Currently, there are no prescribed therapies to control oxidative stress; however, there are strategies to elevate antioxidant defenses and overcome related health challenges based on the adoption of nutritional therapies. It is well known that herbal teas such, as hibiscus, rooibos, and yerba mate, are important sources of antioxidants, able to prevent some oxidation-related stresses. These plants produce several bioactive metabolites, have a pleasant taste, and a long-lasting history as safe foods. This paper reviews the literature on hibiscus, rooibos, and yerba mate teas in the context of nutritional strategies for the attenuation of oxidative stress-related glycoxidation and neurodegeneration, and, here, Alzheimer’s Disease is approached as an example. The focus is given to mechanisms of glycation inhibition, as well as neuroprotective in vitro effects, and, in animal studies, to frame interest in these plants as nutraceutical agents related to current health concerns.

Preparation of Monascus-fermented ginkgo seeds: optimization of fermentation parameters and evaluation of bioactivity

In this study, a high monacolin K yield was achieved through solid-state fermentation of Ginkgo biloba seeds. Monascus purpureus suspension made from red yeast rice was used as spore inoculum. Fermentation conditions in solid-state fermentation were optimized using response surface methodology, and the optimal conditions for the maximum monacolin K yield (17.71 ± 1.57 mg/g) were 0.22% ammonium sulfate, 0.34% ammonium chloride, 0.05% magnesium sulfate, fermentation time of 12 days, inoculation volume of 11%, and temperature of 27 °C. The total phenolic content of Monascus-fermented ginkgo seeds attained 9.67 mg GAE/g, 4.88-fold higher than that of unfermented ginkgo seeds. The scavenging abilities of DPPH and ABTS free radicals increased to 9.79 mg TE/g and 13.92 mg TE/g, respectively. These findings highlight the importance of investigating the optimal fermentation conditions for maximum monacolin K yield and the utilization value of ginkgo seed as fermentation substrate for higher bioactivities.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-022-01078-z.

Kombucha: A review of substrates, regulations, composition, and biological properties

Kombucha has been gaining prominence around the world and becoming popular due to its good health benefits. This beverage is historically obtained by the tea fermentation of Camellia sinensis and by a biofilm of cellulose containing the symbiotic culture of bacteria and yeast (SCOBY). The other substrates added to the C. sinensis tea have also been reported to help kombucha production. The type as well as the amount of sugar substrate, which is the origin of SCOBY, in addition to time and temperature of fermentation influence the content of organic acids, vitamins, total phenolics, and alcoholic content of kombucha. The route involved in the metabolite biotransformation identified in kombucha so far and the microorganisms involved in the process need to be further studied. Some nutritional properties and benefits related to the beverage have already been reported. Antioxidant and antimicrobial activities and antidiabetic and anticarcinogenic effects are some of the beneficial effects attributed to kombucha. Nevertheless, scientific literature needs clinical studies to evaluate these benefits in human beings. The toxic effects associated with the consumption of kombucha are still unclear, but due to the possibility of adverse reactions occurring, its consumption is contraindicated in infants and pregnant women, children under 4-years-old, patients with kidney failure, and patients with HIV. The regulations in place for kombucha address a number of criteria, mainly for the pH and alcohol content, in order to guarantee the quality and safety of the beverage as well as to ensure transparency of information for consumers.

Purple tea (Camellia sinensis var. assamica) leaves as a potential functional ingredient: From extraction of phenolic compounds to cell-based antioxidant/biological activities

A statistical optimization study was used to maximize the extraction of bioactive compounds and antioxidant activity from green tea derived from purple leaves of Camellia sinensis var. assamica. Simultaneous optimization was applied, and a combination of 60 °C, 15 min, and a mass-solvent ratio of 1 g of dehydrated purple leaves to 62.3 mL of an ethanol/citric acid solution, were determined as the ideal extraction conditions. The optimized extract of purple tea leaves (OEPL) contained showed stability in relation to variations in pH, and lyophilized OEPL exerted cytotoxic and antiproliferative effects against cancerous cells (A549 and HCT8), demonstrated antimicrobial activity towards Listeria monocytogenes (ATCC 7644), Staphylococcus aureus (ATCC 13565) and Staphylococcus epidermidis (ATCC 12288), inhibition of α-amylase and α-glycosidase enzymes and reduced the release of pro-inflammatory cytokines (TNF-α, CXCL2/MIP-2, and IL-6) in lipopolysaccharides-stimulated RAW 264.7 macrophages. Thus, our results provide a broad assessment of the bioactivity of "green" extracts obtained by a simple and low-cost process using non-toxic solvents, and they have the potential to be used for technological applications.

Polypodium vulgare L. (Polypodiaceae) as a Source of Bioactive Compounds: Polyphenolic Profile, Cytotoxicity and Cytoprotective Properties in Different Cell Lines

Pteridophytes, represented by ferns and allies, are an important phytogenetic bridge between lower and higher plants. Ferns have evolved independently of any other species in the plant kingdom being its secondary metabolism a reservoir of phytochemicals characteristic of this taxon. The study of the potential uses of Polypodium vulgare L. (Polypodiaceae) as medicinal plant has increased in recent years particularly when in 2008 the European Medicines Agency published a monograph about the rhizome of this species. Our objective is to provide scientific knowledge on the polar constituents extracted from the fronds of P. vulgare, one of the main ferns of European distribution, to contribute to the validation of certain traditional uses. Specifically, we have characterized the methanolic extract of P. vulgare fronds (PVM) by HPLC-DAD and investigated its potential cytotoxicity, phototoxicity, ROS production and protective effects against oxidative stress by using in vitro methods. The 3T3, HaCaT, HeLa, HepG2, MCF-7 and A549 were the cell lines used to evaluate the possible cytotoxic behaviour of the PVM. HPLC-DAD was utilized to validate the polyphenolic profile of the extract. H₂O₂ and UVA were the prooxidant agents to induce oxidative stress by different conditions in 3T3 and HaCaT cell lines. Antioxidant activity of in vitro PVM in 3T3 and HaCaT cell lines was evaluated by ROS assay. Our results demonstrate that PVM contains significant amounts of shikimic acid together with caffeoylquinic acid derivatives and flavonoids such as epicatechin and catechin; PVM is not cytotoxic at physiological concentrations against the different cell lines, showing cytoprotective and cellular repair activity in 3T3 fibroblast cells. This biological activity could be attributed to the high content of polyphenolic compounds. The fronds of the P. vulgare are a source of polyphenolic compounds, which can be responsible for certain traditional uses like wound healing properties. In the present work, fronds of the common polypody are positioned as a candidate for pharmaceutical applications based on traditional medicine uses but also as potential food ingredients due to lack of toxicity at physiological concentrations.

Cellular Defensive Mechanisms of Tea Polyphenols: Structure-Activity Relationship

Tea is particularly rich in polyphenols, including catechins and theaflavins, thearubigins, flavonols, and phenolic acids, which are believed to contribute to the health benefits of tea. The health-promoting effects of tea polyphenols are believed to be related to their cellular defensive properties. This review is intended to briefly summarize the relationship between the chemical structures of tea polyphenols and their biological activities. Tea polyphenols appear as direct antioxidants by scavenging reactive oxygen/nitrogen species; chelating transition metals; and inhibiting lipid, protein, and DNA oxidations. They also act directly by suppressing “pro-oxidant” enzymes, inducing endogenous antioxidants, and cooperating with vitamins. Moreover, tea polyphenols regulate cellular signaling transduction pathways, importantly contributing to the prevention of chronic diseases and the promotion of physiological functions. Apparently, the features in the chemical structures of tea polyphenols are closely associated with their antioxidant potentials.

Recent Applications of Mixture Designs in Beverages, Foods, and Pharmaceutical Health: A Systematic Review and Meta-Analysis

Design of Experiments (DoE) is a statistical tool used to plan and optimize experiments and is seen as a quality technology to achieve products excellence. Among the experimental designs (EDs), the mixture designs (MDs) stand out, being widely applied to improve conditions for processing, developing, or formulating novel products. This review aims to provide useful updated information on the capacity and diversity of MDs applications for the industry and scientific community in the areas of food, beverage, and pharmaceutical health. Recent works were selected following the Preferred Reporting Items for Systematic Review and Meta-Analyses statement (PRISMA) flow diagram. Data analysis was performed by self-organizing map (SOM) to check and understand which fields of application/countries/continents are using MDs. Overall, the SOM indicated that Brazil presented the largest number of works using MDs. Among the continents, America and Asia showed a predominance in applications with the same amount of work. Comparing the MDs application areas, the analysis indicated that works are prevalent in food and beverage science in the American continent, while in Asia, health science prevails. MDs were more used to develop functional/nutraceutical products and the formulation of drugs for several diseases. However, we briefly describe some promising research fields in that MDs can still be employed.

Plant cell cultures of Nordic berry species: Phenolic and carotenoid profiling and biological assessments

Plant cell cultures from cloudberry (CL), lingonberry (LI), stone berry (ST), arctic bramble (AB), and strawberry (SB) were studied in terms of their polyphenol and carotenoid composition, antioxidant activity, antihemolytic activity and cytotoxicity effects on cancerous cells. High-resolution mass spectrometry data showed that LI, presented the highest antioxidant activity, contained the highest contents of flavones, phenolic acids, lignans, and total carotenoids, while CL, ST and SB presented the opposite behavior. AB and SB presented the lowest FRAP and CUPRAC values, while AB and CL presented the lowest reducing power. SB presented the lowest antioxidant activity measured by single electron transfer assays and the lowest content of lignans, phenolic acids, and flavones. CL and LI decreased the viability of in vitro mammary gland adenocarcinoma while only LI decreased the viability of in vitro lung carcinoma and showed protective effects of human erythrocytes against mechanical hemolysis.

Therapeutic targets of natural products for the management of cardiovascular symptoms of coronavirus disease 2019

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first occurred in China in December 2019 and subsequently spread all over the world with cardiovascular, renal, and pulmonary symptoms. Therefore, recognizing and treating the cardiovascular sign and symptoms that caused by coronavirus disease 2019 (COVID-19) can be effective in reducing patient mortality. To control the COVID-19-related cardiovascular symptoms, natural products are considered one of the promising choices as complementary medicine. Scientists are struggling to discover new antiviral agents specific to this virus. In this review, the natural products for management of cardiovascular symptoms of COVID-19 are categorized into three groups: (a) natural products with an impact on angiotensin II type 1 receptor; (b) natural products that inhibit angiotensin-converting enzyme activity; and (c) natural products that mimic adenosine activity. All these natural products should undergo clinical investigations to test their efficacy, safety, and toxicity in the treatment of cardiovascular symptoms of COVID-19. This article summarizes agents with potential efficacy against COVID-19-related cardiovascular symptoms.

Ellagitannins from jabuticaba (Myrciaria jaboticaba) seeds attenuated inflammation, oxidative stress, aberrant crypt foci, and modulated gut microbiota in rats with 1,2 dimethyl hydrazine-induced colon carcinogenesis

Since dietary factors are thought to be responsible for high colon cancer risk, we investigated the chemopreventive effect of jabuticaba seed extract (LJE) by administering yogurt with or without LJE against 1,2 dimethyl hydrazine (DMH)-induced colon carcinogenesis in rats. Results showed that LJE contained a total phenolic content of 57.16 g/100 g of seed extract in which 7.67 and 10.09 g/100 g represented total flavonoids and ellagitannins, respectively. LJE protected DNA and human LDL against induced in vitro oxidation, which was associated with the ellagitannin content and with the free-radical scavenging and reducing capacities. LJE alone had a non-clastogenicity/aneugenicity property, but in combination with cisplatin, it enhanced the chromosome aberrations in cancer cells. In colon cancer-induced rats, yogurt with or without LJE caused a reduction in pro-inflammatory parameters, decreased the RNA expression of antiapoptotic cytokines and increased the expression of proapoptotic cytokines. Moreover, LJE attenuated colon cancer initiation and progression by decreasing aberrant crypt foci and LJE recovered the gut microbiome. Together, this evidence suggests that LJE provides chemopreventive protection against colon cancer development by reducing inflammation and increasing proapoptotic pathways.

Extraction optimization of bioactive compounds from ora-pro-nobis (Pereskia aculeata Miller) leaves and their in vitro antioxidant and antihemolytic activities

Ora-pro-nobis (Pereskia aculeata Miller) is a non-conventional food plant common in Brazil. The objective of this study was to optimize the extraction of bioactive phenolic compounds from ora-pro-nobis leaves by employing solvent mixtures. Ten extracts were obtained with water, ethanol, acetone, and their binary and ternary mixtures, evaluating the chemical composition, antioxidant activity and bioactivities in vitro. The response surface methodology was applied to model the results and calculate the optimal solvent composition, which is 60% water, 40% ethanol and 0% acetone. The optimized extract is rich in phenolic compounds (64 mg GAE/g) and proteins (823 mg/g) and presents antioxidant activity (in intracellular media as well) and inhibits lipid peroxidation (32%) along with hypotonic hemolysis (H₅₀ = 0.339%), it does not present toxicity in vitro against cancer and normal cells. This is the first report of chicoric, caffeoyl-hexaric and coumaroyl-hexaric acids and some glycosylate derivatives of flavonols in ora-pro-nobis leaves.

Antigenotoxic, antiproliferative and antimetastatic properties of a combination of native medicinal plants from Argentina

ETHNOPHARMACOLOGICAL RELEVANCE

Jarilla is the common name of an appreciated group of native plants from the semi-arid region in Argentina (Larrea cuneifolia Cav., Larrea divaricata Cav. and Zuccagnia punctata Cav.) that have been historically consumed to heal respiratory, musculoskeletal and skin ailments, as well as recommended for weakness/tiredness, hypertension, diabetes and cancer treatment. It was previously reported that some biological properties could be improved when these plants are used jointly. Infusions of a defined mixture, composed by three Jarilla species, L. cuneifolia: L. divaricata: Z. punctata (0.5:0.25:0.25) (HM2) showed synergistic and additive effect on antioxidant activity even after passing through the gastro-duodenal tract.

AIM OF THE STUDY

The main purpose of this work was to evaluate antigenotoxic, antitumor, and anti-metastatic properties of the Jarilla species that grow in the Northwest of Argentina and a herbal combination of them.

MATERIAL AND METHODS

Infusions of Jarilla mixture (HM2), and of each single plant species were prepared. Phenolic profiles of infusions were analyzed by HPLC-ESI-MS/MS and two relevant chemical markers were quantified. The antigenotoxic activity was evaluated by using the Ames test and the Cytokinesis-Block Micronucleus (CBMN) assay against direct mutagens. Evaluations of both cytotoxicity and antiproliferative effects were conducted on tumor and non-tumor cell lines. Both in vivo tumoral growth and metastasis inhibition were evaluated by using a carcinoma model on Balb/c mice.

RESULTS

HM2 mix could suppress genetic and chromosome mutations induced by 4-nitro-o-phenylendiamine (4-NPD) and doxorubicin. Herbal mixture and single plant infusions showed cytotoxic effect against mammary, uterus, and brain tumoral cells without a selective action vs normal human cell line. HM2 mix was able to reduce mammary tumor mass on the Balb/c mice model and showed a significant reduction in the number of metastatic nodules in the lungs.

CONCLUSIONS

Our results suggest that the combinations of three Jarilla species from northwest Argentina would be a promising alternative to treat or slow down the development of chronic diseases, such as cancer.

Polyphenols of jabuticaba [Myrciaria jaboticaba (Vell.) O.Berg] seeds incorporated in a yogurt model exert antioxidant activity and modulate gut microbiota of 1,2-dimethylhydrazine-induced colon cancer in rats

The chemical composition, antioxidant activity (AA), cytotoxic activity, antihemolytic effects, and enzyme inhibition (EI) of lyophilized jabuticaba (Myrciaria jaboticaba) seed extract (LJE) was studied. The main compounds found were castalagin, vescalagin, procyanidin A2, and ellagic acid. LJE was more toxic to cancer cells than to normal cells, meaning relative toxicological safety. This cytotoxic effect can be attributed to the pro-oxidant effect observed in the reactive oxygen species (ROS) generation assay. LJE inhibited α-amylase, α-glucosidase, and ACE-I activities and protected human erythrocytes from hemolysis. LJE was incorporated into yogurts at different concentrations and the total phenolic content, AA, and EI increased in a dose-dependent manner. LJE-containing yogurt presented 86% sensory acceptance. The yogurt was administered to Wistar rats bearing cancer and it modulated the gut bacterial microbiota, having a prebiotic effect. LJE is a potential functional ingredient for food companies looking for TPC, AA, and prebiotic effect in vivo.

Extraction and characterization of phytochemical compounds from araçazeiro (Psidium cattleianum) leaf: Putative antioxidant and antimicrobial properties

Underexplored species have phytochemical potential for pharmacological and nutraceutical applications. The fruits of such species, including aracá (Psidium cattleianum Sabine), are rich in specialized metabolites with putative antioxidant and antimicrobial activity; therefore, the leaves of these species are also a potential source of bioactive compounds. In this study, araçazeiro leaves were extracted using an aqueous infusion (Al) and a pressurized liquid extraction system with water (PLE-W), ethanol (PLE-E), and 1:1 water:ethanol ratio combination (PLE-W:E). PLE-W:E yielded a greater diversity of extracted compounds. Nonetheless, all extracts showed inhibitory activity against pathogenic Gram-positive and Gram-negative bacteria and antioxidant activity in the in vitro thiobarbituric acid reactive substances (TBARS) and reactive oxygen species (ROS) assays with rat brain and yeast model systems. Thus, araçazeiro leaves can be exploited as a promising source of bioactive compounds.

Response surface optimization of phenolic compounds extraction from camu-camu (Myrciaria dubia) seed coat based on chemical properties and bioactivity

Food companies should comply with the requirements of a zero-waste concept to adapt to the circular economy requirements. In fruit companies, usually seeds are discarded without proper utilization and extraction of the bioactive compounds. Fruit seeds are sources of chemical compounds that can be extracted, studied, and applied in high value-added products. Thus, in this work the experimental conditions for the water extraction of phenolic compounds from camu-camu (Myrciaria dubia) seed coat were optimized using a central composite design and the desirability function. Total phenolic content (TPC), and condensed tannins (CT), DPPH radical scavenging activity, ferric reducing antioxidant capacity (FRAP), Folin-Ciocalteu reducing capacity (FCRC), and Cu²⁺ chelating ability were assessed. Seed coat extracted for 51.1 min using a 1:34.1 solid:liquid ratio was the optimal condition to extract 6,242 mg gallic acid equivalent (GAE)/100 g of TPC and 695 mg catechin equivalent (CE)/100 g of CT. The optimized extract displayed free-radical scavenging activity, reducing properties and ability to chelate Cu²⁺ , and inhibited the growth of Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella Typhimurium, Salmonella Enteritidis, Bacillus cereus, and Staphylococcus aureus. Additionally, the lyophilized water extract inhibited the in vitro activity of α-amylase, α-glucosidase, and angiotensin converting enzyme and showed cytotoxic effects towards Caco-2, A549, and HepG2 cancer cells, but no cytotoxicity towards IMR90 cells. Vescalagin, castalagin, and 3,4-dihydroxybenzoic acid were the major phenolic compounds identified in the optimized extract. In conclusion, the optimized camu-camu seed coat water extract is a rich source of phenolic compounds with antioxidant, antidiabetic, antihypertensive, and antiproliferative effects. PRACTICAL APPLICATION: Camu-camu fruit pulp and seeds have been studied for their phenolic composition and bioactivity. However, seeds are usually discarded and represent an environmental problem in South American countries. We presented a methodological overview on the extraction optimization of the phenolic compounds from camu-camu seed coat and studied the bioactivity of the optimized extract using chemical, enzymatic, and cell-based experiments. Results can be used by camu-camu processors to obtain a phenolic-rich extract for industrial applications, without any further processing.

Response surface optimization of phenolic compounds from jabuticaba (Myrciaria cauliflora [Mart.] O.Berg) seeds: Antioxidant, antimicrobial, antihyperglycemic, antihypertensive and cytotoxic assessments

The aim of this study was to evaluate the effects of different solvents and maximize the extraction of bioactive compounds from jabuticaba (Myrciaria cauliflora) seeds. In general, the solvent system composed of water and propanone (52:48 v/v) modified the extract polarity and increased extraction yield of bioactive compounds. The optimized extract presented antioxidant capacity measured by different chemical and biological assays. The optimized extract exerted antiproliferative and cytotoxic effects against A549 and HCT8 cells, antimicrobial and antihemolytic effects, inhibited α-amylase/α-glucosidase activities and presented in vitro antihypertensive effect. Nonetheless, the optimized extract showed no cytotoxicity in a human cell model (IMR90). Vescalagin, castalagin and ellagic acid were the major phenolic compounds in the optimized extract. Our results show that jabuticaba seed may be a potential ingredient for the development of potentially functional foods.

A new analytical concept based on chemistry and toxicology for herbal extracts analysis: From phenolic composition to bioactivity

Studies regarding the bioactivity of teas are mainly based on the phenolic composition and in vitro antioxidant activity of the herbal species used in their preparation. The aim of this study was to compare the in vitro and ex vivo antioxidant activity, cytotoxic/antiproliferative activity against cancer cells, the inhibitory activity of α-amylase, α-glucosidase and angiotensin I-converting enzymes, as well as the inhibition of DNA-induced fission of the peroxyl radical, in relation to aqueous extracts of Camellia sinensis var. sinensis (CS), Ilex paraguariensis (IP), Aspalathus linearis (AL) and an optimised extract (OT) containing the three herb species. A bivariate and multivariate statistical approach was employed to associate functional activities with individual phenolic composition. The CS and OT extracts showed the highest levels of hesperidin, quercetin-3-rutinoside, (-)-epigallocatechin-3-gallate and isoquercitrin. The CS and OT extracts showed the highest antioxidant activity, greater ability to inhibit α-amylase and proliferation of HCT8 cells, and greater ability to reduce Folin-Ciocalteu reagent. The AL extract, which is the major source of quercetin-3-rutinoside, hesperidin and isoquercitrin, showed the highest ability to inhibit α-glucosidase, the inhibition of LDL oxidation and protection of human erythrocytes. The IP extract showed the highest inhibition of lipoperoxidation in brain homogenate of Wistar rats, antihypertensive activity, and A549 cell proliferation; chlorogenic acid was its major phenolic compound. In general, the in vitro functionality of each extract was dependent on its chemical composition and the OT extract presented the most varied phenolic composition, and biological activity similar to the CS sample. In conclusion, the mixture of CS, AL, and IP represents a chemical and functional-based strategy to develop functional teas.

Functional Foods: Product Development, Technological Trends, Efficacy Testing, and Safety

Functional foods is a very popular term in the social and scientific media; consequently, food producers have invested resources in the development of processed foods that may provide added functional benefits to consumers' well-being. Because of intrinsic regulation and end-of-use purposes in different countries, worldwide meanings and definitions of this term are still unclear. Hence, here we standardize this definition and propose a guideline to attest that some ingredients or foods truly deserve this special designation. Furthermore, focus is directed at the most recent studies and practical guidelines that can be used to develop and test the efficacy of potentially functional foods and ingredients. The most widespread functional ingredients, such as polyunsaturated fatty acids (PUFAs), probiotics/prebiotics/synbiotics, and antioxidants, and their technological means of delivery in food products are described. The review discusses the steps that food companies should take to ensure that their developed food product is truly functional.

Camu-camu seed (Myrciaria dubia) - From side stream to anantioxidant, antihyperglycemic, antiproliferative, antimicrobial, antihemolytic, anti-inflammatory, and antihypertensive ingredient

Camu-camu (Myrciaria dubia) seeds are discarded without recovering the bioactive compounds. The main aim of the present work was to optimise the solvent mixture to extract higher total phenolic content and antioxidant capacity of camu-camu seeds. The optimised solvent system increased the extraction of phenolic compounds, in which vescalagin and castalagin were the main compounds. The optimised extract displayed antioxidant capacity measured by different chemical and biological assays, exerted antiproliferative and cytotoxic effects against A549 and HCT8 cancer cells, antimicrobial effects, protected human erythrocytes against hemolysis, inhibited α-amylase and α-glucosidase enzymes and presented in vitro antihypertensive effect. Additionally, the optimized extract inhibited human LDL copper-induced oxidation in vitro and reduced the TNF-α release and NF-κB activation in macrophages cell culture. Thus, the use of camu-camu seed showed to be a sustainable way to recover bioactive compounds with in vitro functional properties.

Furtado M, S. Sant’Ana A, Wen M, Zhang L, Granato D. From the Field to the Pot: Phytochemical and Functional Analyses of Calendula officinalis L. Flower for Incorporation in an Organic Yogurt

Edible flowers have been used as ingredients because of their biological activities, taste, and overall appearance. This research was aimed to characterize the chemical composition and in vitro antioxidant activity of the marigold flower (Calendula officinalis L.) extracted with different proportions of water and ethyl alcohol, and the lyophilized extract with higher content of antioxidant compounds was incorporated into an organic yogurt. Results showed that the hydroalcoholic extract (50:50 v/v) presented the highest total phenolic content (TPC), flavonoids, and antioxidant activity (ferric reducing antioxidant power (FRAP), total reducing capacity (TRC), and Cu²⁺/Fe²⁺ chelating ability). Phenolic acids and flavonoids were quantified in the extract by LC-DAD, while 19 compounds were tentatively identified by ESI-MS/MS. The lyophilized marigold extract (LME) also inhibited 12% of Wistar rat’s brain lipid oxidation in vitro, inhibited α-amylase, and α-glucosidase activities, but showed no cytotoxicity towards cancerous cells (HCT8 and A549). However, marigold flower extract protected human erythrocytes against mechanical stress. When added into an organic yogurt model (0 to 1.5%), LME increased TPC and antioxidant activity (2,2-diphenyl-1-picrylhydrazyl (DPPH) and TRC), and the sensory analysis showed that the organic yogurt had an acceptance of 80.4%. Our results show that the use of LME may be a technological strategy to increase the content of bioactive compounds in yogurts.

Flaxleaf Fleabane Leaves (Conyza bonariensis), A New Functional Nonconventional Edible Plant?

This work aimed to investigate the phytochemical composition, nutritional value, antioxidant, antihemolytic, antihyperglycemic, and antiproliferative activities of flaxleaf fleabane (Conyza bonariensis) leaves. Different concentrations of water and ethanol (0:100, 25:75, 50:50, 75:25, and 100:0 v/v) were used in the extraction process and results showed that the hydroalcoholic extract (50:50 v/v) presented the highest total phenolics, ortho-diphenolics, Folin-Ciocalteu reducing capacity, FRAP, and Fe²⁺ chelating ability values. Flaxleaf fleabane leaves (FFL) contained 19.6 g/100 g of fibers and 26 g/100 g of proteins. Ellagic acid, procyanidin A2, caffeic, rosmarinic, gallic, and 2,5-dihydroxybenzoic acids were the main phenolics. This phenolic-rich extract inhibited the lipid oxidation of Wistar rat brain (IC₅₀ = 863.0 mg GAE/L), inhibited α-glucosidase activity (IC₅₀ = 435.4 µg/mL), protected human erythrocytes against mechanical hemolysis at different osmolarity conditions, and showed cytotoxic/antiproliferative effects against human ileocecal adenocarcinoma cells (HCT8; IC₅₀ = 552.6 µg/mL) but no cytotoxicity toward noncancerous human lung fibroblast (IMR90). Overall, FFL showed potential to be explored by food companies to be a source of proteins, natural color substances, and phenolic compounds. PRACTICAL APPLICATION: Flaxleaf fleabane leaves (FFL) are usually burnt or partially given to cattle, without a proper utilization as a source of nutrients for human nutrition. Here, we studied the nutritional composition, phenolic composition, and toxicological aspects of FFL using different biological protocols. FFL was proven to be a rich source of proteins and dietary fibers and showed antioxidant activity measured by chemical and in vitro biological assays. Additionally, as it did protected human red cells and did not show cytotoxicity, we assume FFL has relative safety to be consumed as a nonconventional edible plant.

Chemistry and Biological Activities of Processed Camellia sinensis Teas: A Comprehensive Review

Tea is a typical processed beverage from the fresh leaves of Camellia sinensis [Camellia sinensis (L.) O. Kuntze] or Camellia assamica [Camellia sinensis var. assamica (Mast.) Kitamura] through different manufacturing techniques. The secondary metabolites of fresh tea leaves are mainly flavan-3-ols, phenolic acids, purine alkaloids, condensed tannins, hydrolysable tannins, saponins, flavonols, and their glycoside forms. During the processing, tea leaves go through several steps, such as withering, rolling, fermentation, postfermentation, and roasting (drying) to produce different types of tea. After processing, theaflavins, thearubigins, and flavan-3-ols derivatives emerge as the newly formed compounds with a corresponding decrease in concentrations of catechins. Each type of tea has its own critical process and presents unique chemical composition and flavor. The components among different teas also cause significant changes in their biological activities both in vitro and in vivo. In the present review, the progress of tea chemistry and the effects of individual unit operation on components were comprehensively described. The health benefits of tea were also reviewed based on the human epidemiological and clinical studies. Although there have been multiple studies about the tea chemistry and biological activities, most of existing results are related to tea polyphenols, especially (-)-epigallocatechin gallate. Other compounds, including the novel compounds, as well as isomers of amino acids and catechins, have not been explored in depth.

Multivariate effects of Chinese keemun black tea grades (Camellia sinensis var. sinensis) on the phenolic composition, antioxidant, antihemolytic and cytotoxic/cytoprotection activities

The main objectives of the study were to compare the phenolic composition, chemical and biological antioxidant activities, and cytotoxicity towards IMR90, HCT8, and A549 cell lines of eight grades of Chinese keemun black tea (Camellia sinensis var. sinensis) using a statistical approach. No cytotoxic effects were observed on IMR90 normal cells. Our results all together show that the chemical antioxidant capacity of high-grade black teas measured by DPPH, FRAP, and total reducing capacity assays was correspondingly higher than the mean values of low-grade teas and these antioxidant assays were not associated with cytotoxicity towards cancerous cell lines (HCT8 and A549). High grades of Chinese keemun black teas contained higher contents of total phenolics, flavonoids and ortho-diphenols than lower grades and theaflavin-3,3'-di-gallate could only be detected in high black tea grades (T1 and T2). Intermediate-high keemun black tea grades - C1, C3, T1, and T2 - which also had the highest mean values of TPC, flavonoids, o-diphenols, theaflavin-3-gallate, theaflavin-3'-gallate, Fe²⁺ chelating ability, and chemical antioxidant activity, presented the highest inhibition of Wistar rat's brain oxidation. No clear differentiation and trend were observed between erythrocyte protection and Chinese black tea grades as results clearly showed that intermediate black tea grades (C3 and C4) protected more the human erythrocytes against mechanical stress. Our study shows that although higher Chinese keemun black tea grades (T1 and T2) presented the highest TPC, flavonoids, and chemical antioxidant activity, these in vitro chemical assays were not translated into higher biological activity.

Process for production of ready to drink iced teas from sage (Salvia officinalis L.) and linden (Tilia cordata): pressurized hot water extraction and spray drying

The aim of this study was to produce ready to drink (RTD) iced teas from sage and linden. For this purpose, phenolics of sage and linden were extracted by pressurized hot water extraction (PHWE) and then the extracts obtained were spray dried by the addition of maltodextrin. The powders produced by spray drying were processed into RTD sage and linden iced teas by adding sucrose and citric acid. The optimum conditions of PHWE of sage and linden were at 160 °C and for 10 min and 5 min, respectively. The solubility and microencapsulation efficiency of spray dried powders were found to be greater than 97%. In addition, total phenolic content and antioxidant activity of RTD iced teas are parallel with those of microencapsulated sage and linden powders after pasteurization at 80 °C for 5 min. The sensory analysis of RTD iced teas showed that products were well-accepted by the panelists.

Visualized analysis of within-tissue spatial distribution of specialized metabolites in tea (Camellia sinensis) using desorption electrospray ionization imaging mass spectrometry

Although specialized metabolite distributions in different tea (Camellia sinensis) tissues has been studied extensively, little is known about their within-tissue distribution owing to the lack of nondestructive methodology. In this study, desorption electrospray ionization imaging mass spectrometry was used to investigate the within-tissue spatial distributions of specialized metabolites in tea. To overcome the negative effects of the large amount of wax on tea leaves, several sample preparation methods were compared, with a Teflon-imprint method established for tea leaves. Polyphenols are characteristic metabolites in tea leaves. Epicatechin gallate/catechin gallate, epigallocatechin gallate/gallocatechin gallate, and gallic acid were evenly distributed on both sides of the leaves, while epicatechin/catechin, epigallocatechin/gallocatechin, and assamicain A were distributed near the leaf vein. L-Theanine was mainly accumulated in tea roots. L-Theanine and valinol were distributed around the outer root cross-section. The results will advance our understanding of the precise localizations and in-vivo biosyntheses of specialized metabolites in tea.

Antioxidant and antimicrobial efficacy of a biflavonoid, amentoflavone from Nandina domestica in vitro and in minced chicken meat and apple juice food models

A biflavonoid, amentoflavone isolated from Nandina domestica and characterized by NMR spectral-data analyses was assessed for its antioxidant, and antibacterial potential in vitro and in food-model systems. Amentoflavone exhibited potent antioxidant ability (19.21-75.52%) on scavenging DPPH, ABTS, superoxide, and hydroxyl radicals. Fluorescent images confirmed bacterial membrane depolarization of both the tested pathogens Staphylococcus aureus and Escherichia coli, with a significant reduction in cell viabilities at their respective MIC of 62.5 and 125 µg/mL. Increasing rates of membrane permeability observed in 260 nm-absorbing material, potassium ion, extracellular ATP, and relative electrical conductivity assays confirmed antibacterial mechanistic role of amentoflavone as also evidenced by microscopic studies of SEM and TEM. There was a marked inhibitory effect of amentoflavone with a significant reduction in cell counts of S. aureus and E. coli in minced chicken and apple juice at 4 °C, thus suggesting its nutritional enhancing efficacy as a natural antioxidant and antimicrobial agent.

Comparison of Antioxidant Constituents of Agriophyllum squarrosum Seed with Conventional Crop Seeds

Twelve chemical constituents were identified from the Agriophyllum squarrosum seed (ASS). ASS contained large amounts of flavonoids, which were more concentrated in the seed coat. ASS-coat (1 g) contained 335.7 μg flavonoids of rutin equivalent, which was similar to the flavonoid content in soybean (351.2 μg/g), and greater than that in millet, wheat, rice, peanut, and corn. By LC-MS analysis, the major constituents in ASS were 3-O-[α-L-rhamnopyranosyl-(1→6)-β-D- glucopyranosyl]-7- O-(β-D-glucopyranosyl)-quercetin (1), rutin (4), quercetin-3-O-β-D- apiosyl(1→2)-[α-L-rhamnosyl(l→6)]-β-D-glucoside (2), isorhamnetin-3-O-rutinoside (5), and allantoin (3), compared with isoflavonoids-genistin (16), daidzin (14), and glycitin (18) in soybean. Among constituents in ASS, compounds 1, 2, 4, protocatechuic acid (8), isoquercitrin (11), and luteolin-6-C-glucoside (12) potently scavenged DPPH radicals and intracellular ROS; strongly protected against peroxyl radical-induced DNA scission; and upregulated Nrf2, phosphorylated p38, phosphorylated JNK, and Bcl-2 in HepG2 cells. These results indicate that ASS is rich in antioxidant constituents that can enrich the varieties of food flavonoids, with significant beneficial implications for those who suffer from oxidative stress-related conditions.

PRACTICAL APPLICATION

This study found that A. squarrosum seed contains large amounts of antioxidative flavonoids and compared its chemical constituents with those of conventional foods. These results should increase the interest in planting the sand-fixing A. squarrosum on a large scale, thus preventing desertification and providing valuable foods.

Antioxidant activity, total phenolics and flavonoids contents: Should we ban in vitro screening methods?

As many studies are exploring the association between ingestion of bioactive compounds and decreased risk of non-communicable diseases, the scientific community continues to show considerable interest in these compounds. In addition, as many non-nutrients with putative health benefits are reducing agents, hydrogen donors, singlet oxygen quenchers or metal chelators, measurement of antioxidant activity using in vitro assays has become very popular over recent decades. Measuring concentrations of total phenolics, flavonoids, and other compound (sub)classes using UV/Vis spectrophotometry offers a rapid chemical index, but chromatographic techniques are necessary to establish structure-activity. For bioactive purposes, in vivo models are required or, at the very least, methods that employ distinct mechanisms of action (i.e., single electron transfer, transition metal chelating ability, and hydrogen atom transfer). In this regard, better understanding and application of in vitro screening methods should help design of future research studies on 'bioactive compounds'.