Antioxidant effects of gastrointestinal digested purple carrot extract on the human cells of colonic mucosa

Resveratrol and Its Natural Analogs Mitigate Immune Dysregulation and Oxidative Imbalance in the Endometriosis Niche Simulated in a Co-Culture System of Endometriotic Cells and Macrophages

Background: Inflammation and immune cell dysfunction are critical facilitators of endometriosis pathophysiology. Macrophages are renowned for stimulating lesion growth, vascularization, innervation, and pain generation. By combining macrophages and endometriotic cells, we determined if resveratrol and its natural analogs can target the immune dysregulation and oxidative imbalance in endometriosis. Methods: After treatment with compounds (5, 10, 25 µM), we evaluated the expression of key inflammatory and oxidative stress markers, cytokines release, and ROS production by applying q-PCR, ELISA, Cytometric Beads Array, and multiplexed fluorogenic staining and flow cytometry analysis with bioimaging. Results: The results showed that endometriosis-related macrophages treated with stilbenes have impaired expression of pro-inflammatory markers (IL6, IL8, IL1B, TNF, CCL2, CXCL10, PTGS2). The effect of resveratrol, pterostilbene, and piceatannol was observed, especially in reducing IL1B, CCL2, and CXCL10 genes up to 3.5-, 5-, and 7.7-fold at 25 µM, respectively. Also, with piceatannol or polydatin exposure, the IL-6 decrease was noticeable. This study reported an antioxidant effect by reducing ROS-positive cells from 96% to 48% by pterostilbene. Results from flow cytometry correlated with the transcript activation of detoxification enzymes (SOD, GPX). Conclusions: Prospects for potential therapy based on regulating the immune microenvironment and reducing the accumulation of free radicals with stilbenes application were described in the article.

Potato Protein-Based Vegan Burgers Enriched with Different Sources of Iron and Fiber: Nutrition, Sensory Characteristics, and Antioxidants before and after In Vitro Digestion

The aim of this research was to develop a technology for the production of plant-based burgers (PBBs) based on potato protein, also containing high content of iron and appropriately selected fats. The produced PBBs were characterized in terms of their nutritional and bioactive properties both before and after the in vitro digestion process. It was found that the produced burger was characterized by high protein content, ranging from 20.80 to 22.16 g/100 g. It was also shown to have a high dietary fiber content, ranging from 8.35 to 9.20 g/100 g. The main fraction of dietary fiber in the tested samples was insoluble fiber, which accounted for approximately 89% of the total fiber content. In addition, noteworthy is the high digestibility of the protein, reaching approximately 95% for the potato fiber used in the formulation, and about 85% for the oat fiber. Produced PBBs also provide significant amounts of iron, with the use of an organic iron source greatly increasing its quantity in the final product. The analyzed antioxidant properties before and after the digestion process showed a tenfold increase in biological activity after digestion, indicating that the examined PBBs may counteract oxidative stress. Analyzing the chemical and biological properties, it is impossible not to assess consumer attractiveness. It has been shown that PBB1, which contains potato fiber and powdered sprouts enriched with ferritin, received the highest attractiveness ratings among respondents.

An overview on the cellular mechanisms of anthocyanins in maintaining intestinal integrity and function

Structural and functional changes of the intestinal barrier, as a consequence of a number of (epi)genetic and environmental causes, have a main role in penetrations of pathogens and toxic agents, and lead to the development of inflammation-related pathological conditions, not only at the level of the GI tract but also in other extra-digestive tissues and organs. Anthocyanins (ACNs), a subclass of polyphenols belonging to the flavonoid group, are well known for their health-promoting properties and are widely distributed in the human diet. There is large evidence about the correlation between the human intake of ACN-rich products and a reduction of intestinal inflammation and dysfunction. Our review describes the more recent advances in the knowledge of cellular and molecular mechanisms through which ACNs can modulate the main mechanisms involved in intestinal dysfunction and inflammation, in particular the inhibition of the NF-κB, JNK, MAPK, STAT3, and TLR4 proinflammatory pathways, the upregulation of the Nrf2 transcription factor and the expression of tight junction proteins and mucins.

Heating and storage of structured acylglycerols with succinyl-linked stigmasterol residue does not cause negative chemical or biological changes

Four structured acylglycerols with stigmasterol bonded by a succinyl linker were investigated and their stability were analyzed. Samples were heated to 60 °C and kept at that temperature to simulate storage, and to 180 °C to simulate frying conditions. The degradation of the synthesized compounds and formed derivatives was determined, and their cytotoxicity and genotoxicity on normal human cells from the digestive system was determined. Holding at 180 °C resulted in greater degradation of the compounds than holding at 60 °C. The most stable compound in each sample proved to be one with oleic acid in its structure-1,3-dioleoyl-2-stigmasterylsuccinoyl-sn-glycerol (DO2SSt) at 60 °C and 1,2-dioleoyl-3-stigmasterylsuccinoyl-sn-glycerol (DO3SSt) at 180 °C. These results indicate that the type of fatty acid in the molecule is more important than its position in the glycerol structure. None of the diacylmonostigmasterylsuccinoyl-sn-glycerols (DASStGs) before or after heating exhibited cytotoxic or genotoxic potential to small intestine and colon mucosa cells.

Natural resveratrol analogs differentially target endometriotic cells into apoptosis pathways

The specific characteristics of endometriotic cells are their ability to evade the apoptotic machinery and abnormal response to apoptotic stimuli. Natural-originated compounds may constitute a beneficial strategy in apoptosis modulation in endometriosis. We investigated and compared the potency of natural resveratrol analogs, including piceatannol, polydatin, and pterostilbene, in targeting cell death pathways, including apoptosis-related morphologic and biochemical processes, alongside the modulation of the critical genes expression. Upon resveratrol and pterostilbene treatment, a significant reduction of endometriotic cell viability and an increased apoptotic proportion of cells were noted. The lower antiproliferative potential was found for piceatannol and polydatin. Endometrial stromal T HESC cells were significantly more resistant than endometriotic epithelial 12Z cells to the cytotoxic activity of all analyzed compounds. They differentially affected endometriotic cell viability, cell cycle, anti- and proapoptotic genes regulation, caspases expression and enzymatic activity, and DNA fragmentation. Pterostilbene-mediated endometriotic cell apoptosis modulation was confirmed to be most effective but without evident caspase 3 upregulation. Our study provides valuable insight into the apoptogenic activity of resveratrol and its natural analogs in endometriotic cells. Data obtained revealed the highest therapeutic potential of pterostilbene by effectively targeting cell death determinants in endometriosis, strengthening its optimization in further extensive research.

Thermo-oxidative stability and safety of new acylglycerols with stigmasterol residue: Effects of fatty acids saturation and position in the glycerol backbone

The safety and thermoxidative stability of new diacyl-stigmasterylcarbonoyl-sn-glycerols (DAStGs) with two molecules of palmitic or oleic acids and one molecule of stigmasterol at the sn-2 or sn-3 position were studied. After heating to 60 °C, the compounds with stigmasterol at the sn-2 position were more stable than those with stigmasterol at the sn-3 position. The lowest level of degradation of stigmasterol after heating to 180 °C was detected for both compounds with oleic acid, followed by the samples with palmitic acid. The high content of SOPs, especially triolSt, as well as the high level of dimers showed the most effect on the cytotoxicity of DAStGs heated at both temperatures. DAStGs with oleic acid at sn-1,3 and stigmasterol at sn-2 position were the most stable compounds. Both oleic acid and the location of stigmasterol in the middle of the glycerol molecule play an important role in increasing the thermoxidative stability of stigmasterol.

Bioactive Substances of Potato Juice Reveal Synergy in Cytotoxic Activity against Cancer Cells of Digestive System Studied In Vitro

More and more literature data indicate the health-promoting effect of potato juice (PJ). However, to date, it has not been precisely explained which of the many compounds present in PJ exhibit biological activity. The work aimed to establish the antiproliferative effect of gastrointestinal digested PJ and the products of its processing. Fresh PJs derived from three edible potato varieties, industrial side stream resulting from starch production, partially deproteinized PJ derived from feed protein production line, and three different potato protein preparations subjected to digestion in the artificial gastrointestinal tract were used in this study. The cytotoxic potential of glycoalkaloids (GAs), phenolic acids, digested PJ, and products of PJ processing was determined in human normal and cancer cells derived from the digestive system. The results showed that GAs exhibit concentration-dependent cytotoxicity against all analyzed cell lines. In contrast, phenolic acids (caffeic, ferulic, and chlorogenic acid) do not show cytotoxicity in the applied cell lines. A correlation between cytotoxic potency and GAs content was found in all PJ products studied. The most potent effects were observed under treatment with deproteinized PJ, a product of industrial processing of PJ, distinguished by the highest effective activity among the fresh juice products studied. Moreover, this preparation revealed a favorable cytotoxicity ratio towards cancer cells compared to normal cells. Statistical analysis of the obtained results showed the synergistic effect of other bioactive substances contained in PJ and its products, which may be crucial in further research on the possibility of using PJ as a source of compounds of therapeutic importance.

Anti-Inflammatory Activity of an In Vitro Digested Anthocyanin-Rich Extract on Intestinal Epithelial Cells Exposed to TNF-α

Background: The consumption of foods rich in anthocyanins (ACN) have been associated with beneficial properties in chronic inflammatory disorders such as intestinal bowel diseases (IBD). These effects were attributed not only to a direct antioxidant mechanism but also to the modulation of cell redox-dependent signaling. However, ACN bioavailability is low for their poor stability in the digestive tract, so ACN gastrointestinal digestion should be considered. Methods: To have a more realistic knowledge of the effects of ACN, we performed an in vitro simulated gastrointestinal digestion of an ACN-rich purified and standardized bilberry and blackcurrant extract (BBE), followed by an evaluation of ACN composition modification (HPLC-DAD and pH differential method) and antioxidant activity (FRAP assay). Then, we studied the effects of BBE gastrointestinal extract on Caco-2 exposed to TNF-α. Results: The results confirmed the high instability of ACN in the mild alkaline environment of the small intestine (17% recovery index). However, the digested BBE maintained part of its bioactivity. Additionally, BBE gastrointestinal extract inhibited the TNF-α-induced NF-κB pathway in Caco-2 and activated the Nrf2 pathway. Conclusions: Although ACN stability is affected by gastrointestinal digestion, the anti-inflammatory and antioxidant activity of digested extracts were confirmed; thus, the loss of ACN can probably be counterweighed by their metabolites. Then, ACN introduced by diet or food supplements could represent an approach for IBD prevention.

Efficient production of anthocyanins in Saccharomyces cerevisiae by introducing anthocyanin transporter and knocking out endogenous degrading enzymes

Anthocyanins are natural pigments found in various plants. As multifunctional natural compounds, anthocyanins are widely used in food, pharmaceuticals, health products, and cosmetics. At present, the anthocyanins are heterologously biosynthesized in prokaryotes from flavan-3-ols, which is rather expensive. This study aimed to metabolically engineer Saccharomyces cerevisiae for anthocyanin production. Anthocyanin production has been extensively studied to understand the metabolic pathway enzymes in their natural hosts, including CHS (chalcone synthase); FLS (flavonol synthase); CHI (chalcone isomerase); F3H (flavanone 3-hydroxylase); F3′H (flavonoid 3′-hydroxylase); F3′5′H (flavonoid 3′,5′-hydroxylase); DFR (dihydroflavonol 4-reductase); ANS (anthocyanidin synthase); LAR (leucoanthocyanidin reductase); and UFGT (flavonoid 3-O-glucosyltransferase). The anthocyanin transporter MdGSTF6 was first introduced and proven to be indispensable for the biosynthesis of anthocyanins. By expressing MdGSTF6, FaDFR, PhANS₀, and Dc3GT and disrupting EXG1 (the main anthocyanin-degrading enzyme), the BA-22 strain produced 261.6 mg/L (254.5 mg/L cyanidin-3-O-glucoside and 7.1 mg/L delphinidin-3-O-glucoside) anthocyanins from 2.0 g/L dihydroflavonols, which was known to be the highest titer in eukaryotes. Finally, 15.1 mg/L anthocyanins was obtained from glucose by expressing the de novo biosynthesis pathway in S. cerevisiae, which is known to be the highest de novo production. It is the first study to show that through the introduction of a plant anthocyanin transporter and knockout of a yeast endogenous anthocyanin degrading enzyme, the anthocyanin titer has been increased by more than 100 times.

Thermo-oxidative stability of asymmetric distigmasterol-modified acylglycerols as novel derivatives of plant sterols

The study investigated the thermo-oxidative stability of distigmasterol-modified acylglycerols as a new structured acylglycerols. Samples were heated at 60 and 180 °C for 8 h. Their percentage degradation and products formed during heating were compared with free stigmasterol and stigmasteryl esters. The remaining of stigmasterol and fatty acid parts, the formation of stigmasterol oxidation products and the composition of polar and non-polar fractions were analysed using chromatographic methods. The cytotoxicity and genotoxicity were determined with the use of an MTT test and a comet assay, respectively. The highest stability during heating was observed for 2,3-distigmasterylsuccinoyl-1-oleoyl-sn-glycerol (dStigS-OA) and the lowest for 2,3-distigmasterylcarbonoyl-1-oleoyl-sn-glycerol (dStigC-OA). Data showed that the formation of thermo-oxidative degradation products is affected by the temperature and chemical structure of lipids present in the molecule. The dStigMAs bonded by a succinate linker and products formed during their thermo-oxidation showed no cytotoxic or genotoxic activity to normal human cells.

Delving into the Nutraceutical Benefits of Purple Carrot against Metabolic Syndrome and Cancer: A Review

Metabolic syndrome (MetS) constitutes a group of risk factors that may increase the risk of cancer and other health problems. Nowadays, researchers are focusing on food compounds that could prevent many chronic diseases. Thus, people are shifting from dietary supplements towards healthy nutritional approaches. As a nutritious and natural food source, purple carrot (Daucus carota spp. Sativus var. atrorubens Alef.) roots could have an important role in the prevention of MetS as well as cancer. This review provides deep insight into the role of purple carrot’s main bioactive compounds and their effectiveness against MetS and cancer. Phenolic compounds, such as anthocyanin, present in purple carrot roots may be especially productive in avoiding or delaying the onset of cardiovascular disease (CVDs), obesity, diabetes, and cancer. Anthocyanins and other phenolics are successful in reducing metabolic changes and inflammation by inhibiting inflammatory effects. Many researchers have made efforts to employ this vegetable in the prevention and treatment of MetS and cancer. However, more advanced studies are required for the identification of its detailed role, effectiveness, suitable intake, and the effect of its bioactive compounds against these diseases.

Comparison of Flavonoid O-Glycoside, C-Glycosideand Their Aglycones on Antioxidant Capacity and Metabolism during In Vitro Digestion and In Vivo

Flavonoids are well known for their extensive health benefits. However, few studies compared the differences between flavonoid O-glycoside and C-glycoside. In this work, flavonoid O-glycoside (isoquercitrin), C-glycoside (orientin), and their aglycones (quercetin and luteolin) were chosen to compare their differences on antioxidant activities and metabolism during in vitro digestion and in vivo. In vitro digestion, the initial antioxidant activity of the two aglycones was very high; however, they both decreased more sharply than their glycosides in the intestinal phase. The glycosidic bond of flavonoid O-glycoside was broken in the gastric and intestinal stage, while the C-glycoside remained unchanged. In vivo, flavonoid O-glycoside in plasma was more elevated than C-glycoside on the antioxidant activity; however, flavonoid C-glycoside in urine was higher than O-glycoside. These results indicate that differences of flavonoid glycosides and their aglycones on antioxidant activity are closely related to their structural characteristics and metabolism in different samples. Aglycones possessed higher activity but unstable structures. On the contrary, the sugar substituents reduced the activity of flavonoids while improving their stability and helping to maintain antioxidant activities after digestion. Especially the C-glycoside was more stable because the stability of the C–C bond is higher than that of the C–O bond, which contributes to the difference between flavonoid O-glycoside and C-glycoside on the absorption and metabolism in vivo. This study provided a new perspective for comparing flavonoid O-glycoside, flavonoid C-glycoside, and their aglycones on their structure–activity relationship and metabolism.

Stabilization of Lycium ruthenicum Murr. anthocyanins by natural polyphenol extracts

Anthocyanins are a group of flavonoids widely used as natural pigments and in functional foods. However, the sensitivity of anthocyanins to environment factors limits their utilization. The present study examined the stabilizing effects of polyphenol extracts from raspberry, sea-buckthorn, Lonicera edulis, and blackcurrant on Lycium ruthenicum Murr (LRM)-derived anthocyanins. After light and heat exposure, contents of total anthocyanins and the monomers were detected with the pH differential method and the HPLC. Remarkably, polyphenol extracts from raspberry, Lonicera edulis and blackcurrant extended the half-lives of anthocyanins, while the effect of the sea-buckthorn extracts was negligible. Noticeably, petunidin-3-O-[6-O-(4-O-trans-p-coumaroyl-alpha-L-rhamnopyranosyl)-beta-D-glucopyranoside]-5-O-[beta-D-glucopyranoside], the major component of LRM-derived anthocyanins, exhibited a dramatic increase in half-life with the presence of polyphenol extracts from raspberry, Lonicera edulis, and blackcurrant. In summary, our findings suggest the polyphenol extracts could be developed into copigments for stabilization of anthocyanins.

Functional relationship of vegetable colors and bioactive compounds: Implications in human health

Vegetables are essential protective diet ingredients that supply ample amounts of minerals, vitamins, carbohydrates, proteins, dietary fiber, and various nutraceutical compounds for protection against various disease conditions. Color is the most important quality parameter for the farmers to access the harvest maturity while for the consumer's reliable indices to define acceptability or rejection. The colored vegetables contain functional compounds like chlorophylls, carotenoids, betalains, anthocyanins, etc. well recognized for their antioxidant, antimicrobial, hypolipidemic, neuroprotective, antiaging, diuretic, and antidiabetic properties. Recently, there has been a shift in food consumption patterns from processed to semi-processed or fresh fruits and vegetables to ensure a healthy disease-free life. This shifted the focus of agriculture scientists and food processors from food security to nutrition security. This has resulted in recent improvements to existing crops like blue tomato, orange cauliflower, colored and/or black carrots, with improved color, and thus enriched bioactive compounds. Exhaustive laboratory trials though are required to document and establish their minimum effective concentrations, bioavailability, and specific health benefits. Efforts should also be directed to breed color-rich cultivars or to improve the existing varieties through conventional and molecular breeding approaches. The present review has been devoted to a better understanding of vegetable colors with specific health benefits and to provide in-hand information about the effect of specific pigment on body organs, the effect of processing on their bioavailability, and recent improvements in colors to ensure a healthy lifestyle.

Chemopreventive Effect of Dietary Anthocyanins against Gastrointestinal Cancers: A Review of Recent Advances and Perspectives

Anthocyanins are a group of dietary polyphenols, abundant mainly in fruits and their products. Dietary interventions of anthocyanins are being studied extensively related to the prevention of gastrointestinal (GI) cancer, among many other chronic disorders. This review summarizes the hereditary and non-hereditary characteristics of GI cancers, chemistry, and bioavailability of anthocyanins, and the most recent findings of anthocyanin in GI cancer prevention through modulating cellular signaling pathways. GI cancer-preventive attributes of anthocyanins are primarily due to their antioxidative, anti-inflammatory, and anti-proliferative properties, and their ability to regulate gene expression and metabolic pathways, as well as induce the apoptosis of cancer cells.

Technological and antioxidant properties of proteins obtained from waste potato juice

The article presents the technological and antioxidant properties of potato juice (PJ) protein concentrate obtained by the novel ultrafiltration method. Commercial products, obtained from waste PJ by the traditional method of acid coagulation of proteins, were studied for comparison. Functional properties such as water or oil absorption, foaming capacity, and foam stability (FS) as well as solubility at various pH were assessed. Moreover, the total phenolic compound content, antioxidant activity, and mineral composition were determined. The results showed that PJ protein concentrate obtained by ultrafiltration has good oil absorption properties (6.30 mL/g), which is more than two times higher than the commercial proteins used in the comparison (P2 = 2.33 mL/g and P3 = 2.67 mL/g). Moreover, the ability to create and stabilize foam was also higher (FS ranging from 20.0% at pH = 10 to 11.3% at pH = 2 after 60 min of testing). It had higher content of macro- and microelements and antioxidant activity compared to other samples. Therefore, it is possible to obtain interesting potato protein concentrate from the waste product of the starch production process, which may be an interesting raw material for enriching food.

Grown to be Blue-Antioxidant Properties and Health Effects of Colored Vegetables. Part I: Root Vegetables

During the last few decades, the food and beverage industry faced increasing demand for the design of new functional food products free of synthetic compounds and artificial additives. Anthocyanins are widely used as natural colorants in various food products to replenish blue color losses during processing and to add blue color to colorless products, while other compounds such as carotenoids and betalains are considered as good sources of other shades. Root vegetables are well known for their broad palette of colors, and some species, such as black carrot and beet root, are already widely used as sources of natural colorants in the food and drug industry. Ongoing research aims at identifying alternative vegetable sources with diverse functional and structural features imparting beneficial effects onto human health. The current review provides a systematic description of colored root vegetables based on their belowground edible parts, and it highlights species and/or cultivars that present atypical colors, especially those containing pigment compounds responsible for hues of blue color. Finally, the main health effects and antioxidant properties associated with the presence of coloring compounds are presented, as well as the effects that processing treatments may have on chemical composition and coloring compounds in particular.

Phytochemicals in Daucus carota and Their Health Benefits-Review Article

Carrots are a multi-nutritional food source. They are an important root vegetable, rich in natural bioactive compounds, which are recognised for their nutraceutical effects and health benefits. This review summarises the occurrence, biosynthesis, factors affecting concentration, and health benefits of phytochemicals found in Daucus carota. Two hundred and fifty-five articles including original research papers, books, and book chapters were analysed, of which one hundred and thirty articles (most relevant to the topic) were selected for writing the review article. The four types of phytochemicals found in carrots, namely phenolics, carotenoids, polyacetylenes, and ascorbic acid, were summarised. These chemicals aid in the risk reduction of cancer and cardiovascular diseases due to their antioxidant, anti-inflammatory, plasma lipid modification, and anti-tumour properties. Numerous factors influence the amount and type of phytochemicals present in carrots. Genotype (colour differences) plays an important role; high contents of α and β-carotene are present in orange carrots, lutein in yellow carrots, lycopene in red carrots, anthocyanins in the root of purple carrots, and phenolic compounds abound in black carrots. Carotenoids range between 3.2 mg/kg and 170 mg/kg, while vitamin C varies from 21 mg/kg to 775 mg/kg between cultivars. Growth temperatures of carrots influence the level of the sugars, carotenoids, and volatile compounds, so that growing in cool conditions results in a higher yield and quality of carrots, while higher temperatures would increase terpene synthesis, resulting in carrots with a bitter taste. It is worthwhile to investigate the cultivation of different genotypes under various environmental conditions to increase levels of phytochemicals and enhance the nutritional value of carrot, along with the valorisation of carrot by-products.

The Nutritional Value and Biological Activity of Concentrated Protein Fraction of Potato Juice

Potato protein is recognized as one of the most valuable nonanimal proteins due to the high content of essential amino acids. So far, it has not been used in human nutrition on a large scale due to technological limitations regarding its acquisition. In this study, the protein fraction of potato juice was concentrated with the use of membrane separation. The obtained potato juice protein concentrate (PJPC) was characterized in terms of nutritional value and biological activity, and the amino acid composition, mineral content, and antioxidant properties were determined. Moreover, in vitro cytotoxic activity against cancer cells of the gastrointestinal tract was investigated. The results of the present study indicate that PJPC is an excellent source of lysine and threonine, while leucine is its limiting amino acid, with an amino acid score (AAS) of 65%. Moreover, PJPC contains substantial amounts of Fe, Mn, K, and Cu. As demonstrated experimentally, PJPC is also characterized by higher antioxidant potential than potato itself. Biological activity, however, is not limited to antioxidant activity alone. Cytotoxicity studies using a gastric cancer cell line (Hs 746T), a colon cancer cell line (HT-29), and human colon normal cells (CCD 841 CoN) proved that PJPC is characterized by selective activity against cancer cells. It can thus be concluded that the developed method of producing protein concentrate from potato juice affords a product with moderate nutritional value and interesting biological activity.

Protective effects of Phyllanthus phillyreifolius extracts against hydrogen peroxide induced oxidative stress in HEK293 cells

Phyllanthus phillyreifolius, a plant species indigenous to Reunion Island, is used in folk medicine for treating diarrhea and as a diuretic. In the present study acetone and hydroethanol extracts of P. phillyreifolius were evaluated for their cytotoxicity and antioxidant effects using in vitro (TPC, ABTS, DPPH, FRAP, ORAC) and in cellulo (MTT, DCFH-DA, RT-qPCR) assays. Major compounds were evaluated using UPLC-QTOF-MS. MTT cell viability assay showed low cytotoxicity of extracts towards human embryonic kidney 293 (HEK293) cell line. Both extracts were rich in polyphenols (mainly ellagitannins) and showed high antioxidant potential and intracellular ROS decreasing effect. Preconditioning of HEK293 cells with extracts influenced gene expression of antioxidant enzymes, however ROS level decreasing effect was more related to their capacity to scavenge free radicals and with their reducing power. Strong antioxidant activity of extracts as well as the presence of geraniin supports the use of P. phillyreifolius in traditional medicine.

Anti-Colitic Effect of Purple Carrot on Dextran Sulfate Sodium (DSS)-Induced Colitis in C57BL/6J Mice

The anti-colitic effect of purple carrot (PC) on 2% dextran sulfate sodium (DSS)-induced colitis in C57BL6/J mice was compared with those of yellow carrot (YC), beet (BT), and red cabbage (RC). Component analysis showed that PC contained cyanidin-3-xyloglucoside, cyanidin-3-xylosyl(sinapoly-glucosyl)galactoside, cyanidin-3-xylosyl(feruloylglucosyl) galactoside, and cyanidin-3-O-(6-O-glycosyl-2-O-xylosylgalactoside). PC diet (5% in AIN 93G diet) strongly reduced DSS-induced colon shortening and inflammatory cell infiltration in mice, followed by RC, BT, and YC diets. Treatment with PC reduced serum levels of pro-inflammatory cytokines such as tumor necrosis factor-α and interleukin-6 as well as reduced mRNA expression in colon tissue of colitis mice in comparison with other treatments. In addition, PC treatment inhibited colonic mRNA expression of inflammatory factors such as inducible nitric oxide synthase and cyclooxygenase-2 in mice. These results suggest that PC can attenuate the inflammatory reaction in mice with DSS-induced colitis, probably due to the anthocyanins in PC.

Evaluation of the Cellular and Animal Models for the Study of Antioxidant Activity: A Review

The mechanisms of antioxidant activities of phytochemicals are highly complex, so various methods to study them have been developed. However, the diverse available methods show inconsistent results. Different stressors, cell models, and animal models have been used to evaluate the antioxidant properties of phytochemicals. However, the literature still lacks a summary of the effects of different stressors, cell models, and animal models on the evaluation of antioxidant activities. Therefore, the mechanisms of action of different oxidative stimuli and the characteristics of the available cell models and animal models are summarized in this review.

Purple carrot anthocyanins suppress lipopolysaccharide-induced inflammation in the co-culture of intestinal Caco-2 and macrophage RAW264.7 cells

This study was designed to evaluate the anti-inflammatory effects of purple carrot anthocyanins (PCA) with respect to gut inflammation, simulated in a co-culture system consisting of intestinal epithelial Caco-2 cells and RAW264.7 macrophages. The obtained results indicated that PCA extract down-regulates the mRNA expression of proinflammatory interleukins Il-1β (↓91%) and Il-6 (↓69%) as well as inflammatory mediators, such as cyclooxygenase-2 (Cox-2) and inducible nitric oxide synthase (iNos), in lipopolysaccharide-activated RAW264.7 cells. The decrease in the generation of prostaglandin E2 (↓48%) and nitric oxide (↓26%) was observed as a result of the inhibition of Cox-2 (↓25%) and iNos (↓12%) mRNA expressions, respectively. Moreover, the PCA reduced mRNA expression (↓40%) and production (↓17%) of IL-8 in intestinal cells. The anti-inflammatory effect of PCA was contributed to the protection of the intestinal barrier, which was disrupted upon the stimulation of macrophages. These findings may provide preliminary justification for the use of PCA in further studies focused on the prevention and therapy supporting the conventional treatment of inflammatory bowel diseases.

A Gastrointestinally Digested Ribes nigrum L. Fruit Extract Inhibits Inflammatory Response in a Co-culture Model of Intestinal Caco-2 Cells and RAW264.7 Macrophages

Blackcurrant fruits are a rich source of polyphenolic compounds with high antioxidant capacity and potent anti-inflammatory properties. In this study, blackcurrant extract digested in an artificial gastrointestinal tract and its intestinal permeable fraction were investigated for their ability to suppress inflammatory responses induced in a two-component cell culture system of intestinal epithelial cells and macrophages. The obtained results showed the capacity of the extract at a concentration of 1 mg of freeze-dried blackcurrant powder per mL to down-regulate the expression of inflammatory mediators, such as IL-8 (54 ± 7%) and COX-2 (17 ± 6%) in intestinal cells and IL-1α (76 ± 4%), IL-1β (91 ± 2%), and IL-6 (61 ± 5%) in macrophages stimulated with lipopolysaccharides. Inhibited COX-2 (44 ± 6%) and iNOS (15 ± 7%) expression played a role in reducing the production of prostaglandin E₂ (40 ± 20%) and NO (31 ± 9%), respectively. Decreased TNF-α secretion (24 ± 5%) by activated macrophages was also observed after treatment with blackcurrant extract. Moreover, the gastrointestinal-digested extract (0.01-1 mg/mL) dose dependently decreased the enhanced ROS generation (14-54%) and oxidative DNA damage (16-37%) induced in intestinal cells. The increased intestinal permeability caused by proinflammatory mediators, as assessed by transepithelial electrical resistance, was completely counteracted.

Stability improvement of natural food colors: Impact of amino acid and peptide addition on anthocyanin stability in model beverages

Anthocyanins are prone to chemical degradation and color fading in the presence of vitamin C. The potential of three amino acids (l-phenylalanine, l-tyrosine, l-tryptophan) and a polypeptide (ε-poly-l-lysine) in prolonging the color stability of purple carrot anthocyanins (0.025%) in model beverages (0.05% l-ascorbic acid, citric acid, pH 3.0) stored at elevated temperature (40°C/7 days) was examined. In the absence of amino acids or peptides, anthocyanin degraded at first-order reaction rate. Addition of amino acids or peptide (0.1%) increased the color stability of anthocyanins, with the most significant improvement observed for l-tryptophan. The average half-life of anthocyanin color increased from 2 days to 6 days with l-tryptophan addition. Fluorescence quenching measurements revealed that the l-tryptophan interacted with anthocyanins mainly through hydrogen bonding, although some hydrophobic interaction may also have been involved. Overall, this study suggests that amino acid or peptide addition may prolong the color stability of anthocyanin in beverage products.

Oral administration of green plant-derived chemicals and antioxidants alleviates stress-induced cellular oxidative challenge

BACKGROUND

This study examined the efficacy of the combination antioxidant, Formula 42 (F42), on cellular stress indicators in animal and human models of stress-induced oxidative stress.

METHODS

A sub-chronic psychological stress model in rodents was used to induce stress and oxidative stress indicators over a 10-day period during which animals received oral doses of F42 or water. Following treatment, body weight, plasma stress hormone corticosterone, and oxidative capacity were evaluated. In healthy human subjects, a randomized double-blind crossover study was used to examine the antioxidant effect of F42 or placebo in an exercise-induced oxidative stress model. Erythrocyte and plasma oxidative status was evaluated using the fluorescent activation of 2',7'-dichlorofluorescin (DCF) as an indicator.

RESULTS

Oral administration of F42 reduced the corticosterone response to acute stress compared to vehicle but did not differ at the conclusion of the 10-day study. However, F42 administration did reduce stress-induced growth restriction and alleviate DCF activation in circulating erythrocytes by approximately 10% following 10 days of stress exposure. Oral administration of F42 also significantly reduced DCF activation by approximately 10% in healthy human subjects undergoing exercise-induced oxidative stress.

CONCLUSIONS

Oral administration of F42 in rodents produces transient reductions in stress hormones and reduces stress indicators following sub-chronic psychological stress exposure. In humans, F42 acts as an early and potent antioxidant capable of scavenging free radicals within 30 min of ingestion.

Phyto-mediated nanostructured carriers based on dual vegetable actives involved in the prevention of cellular damage

The growing scientific interest in exploitation of vegetable bioactives has raised a number of questions regarding their imminent presence in pharmaceutical formulations. This study intends to demonstrate that a dual combination between vegetable oil (e.g. thistle oil, safflower oil, sea buckthorn oil) and a carrot extract represents an optimal approach to formulate safe carrier systems that manifest cell regeneration effect and promising antioxidant and anti-inflammatory activity. Inclusion of both natural actives into lipid carriers imparted a strong negative charge on the nanocarrier surface (up to -45mV) and displayed average sizes of 70nm to 140nm. The entrapment efficiency of carrot extract into nanostructured carriers ranged between 78.3 and 88.3%. The in vitro release study has demonstrated that the entrapment of the extract represents a viable way for an equilibrated release of carotenoids. Besides the excellent antioxidant properties (e.g. scavenging up to 98% of the free oxygen radicals), the results of cellular integrity (e.g. cell viability of 133%) recommend these nanocarriers based on dual carrot extract-bioactive oil as a promising trend for the treatment of certain disorders in which oxidative stress plays a prominent role. In addition, the lipid nanocarriers based on safflower oil and sea buckthorn oil demonstrated an anti-inflammatory effect on LPS induced THP-1 macrophages, by inhibiting the secretion of two pro-inflammatory cytokines, IL-6 and TNF-α.

New Challenges for the Design of High Value Plant Products: Stabilization of Anthocyanins in Plant Vacuoles

In the last decade plant biotechnologists and breeders have made several attempt to improve the antioxidant content of plant-derived food. Most efforts concentrated on increasing the synthesis of antioxidants, in particular anthocyanins, by inducing the transcription of genes encoding the synthesizing enzymes. We present here an overview of economically interesting plant species, both food crops and ornamentals, in which anthocyanin content was improved by traditional breeding or transgenesis. Old genetic studies in petunia and more recent biochemical work in brunfelsia, have shown that after synthesis and compartmentalization in the vacuole, anthocyanins need to be stabilized to preserve the color of the plant tissue over time. The final yield of antioxidant molecules is the result of the balance between synthesis and degradation. Therefore the understanding of the mechanism that determine molecule stabilization in the vacuolar lumen is the next step that needs to be taken to further improve the anthocyanin content in food. In several species a phenomenon known as fading is responsible for the disappearance of pigmentation which in some case can be nearly complete. We discuss the present knowledge about the genetic and biochemical factors involved in pigment preservation/destabilization in plant cells. The improvement of our understanding of the fading process will supply new tools for both biotechnological approaches and marker-assisted breeding.

Increased Sucrose in the Hypocotyls of Radish Sprouts Contributes to Nitrogen Deficiency-Induced Anthocyanin Accumulation

Effects of nitrogen (N) deficiency and sucrose (Suc) addition on regulation of anthocyanin biosynthesis and their relationship were investigated in this study. Radish sprouts subjected to N deficiency had 50% higher anthocyanin accumulation than when grown in Hoagland solution (a nutrient medium with all macronutrients). The contents of endogenous soluble sugars (Suc, fructose, and glucose) in the hypocotyls were also markedly increased by N limitation, with Suc showing the highest increase. Inhibition of carbohydrate biosynthesis by addition of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) also eliminated N deficiency-induced anthocyanin accumulation. The latter was further supported by the expression of anthocyanin biosynthesis related genes and decreased activities of nitrate reductase in the presence of Suc. Together our results indicate that N deficiency-induced anthocyanin accumulation was, at least partly, dependent on the increase of the soluble sugar, especially Suc. This work is the first comprehensive study on relationship between N deficiency and sugar content on anthocyanin accumulation in the hypocotyls of radish sprouts.