Antioxidant activity and protective effect of extract of Celosia cristata L. flower on tert-butyl hydroperoxide-induced oxidative hepatotoxicity

Celosia cristata L.: A review of its traditional uses, phytochemistry, pharmacology, toxicology, and quality control, along with network pharmacological analysis of its components and targets

ETHNOPHARMACOLOGICAL RELEVANCE

Celosia cristata L. (C. cristata) is a widely used herb in China and has been used as a medicine for more than 1000 years. The herb has been clinically employed to treat various types of bleeding disorders including metrorrhagia, metrostaxis, and leukorrheal diseases, gastrointestinal infections.

AIM OF THE STUDY

This review provides a comprehensive analysis of C. cristata, encompassing its botany, traditional applications, phytochemistry, pharmacology, safety, and quality control. Additionally, it delves into the prevailing challenges and limitations with contemporary research concerning C. cristata, thus furnishing valuable insights for future investigations in this domain.

MATERIALS AND METHODS

Research data were gathered from authoritative sources including the Pharmacopoeia of China, the Flora of China, as well as various internet databases such as Web of Science, CAS CiFinder, PubMed, Science Direct, and CNKI, along with numerous ancient classics on Chinese herbal medicine.

RESULTS

Clinical applications of C. cristata demonstrate its efficacy in treating dysfunctional uterine bleeding, vaginitis, and pelvic inflammatory disease. Presently, seventy-seven compounds have been isolated, including flavonoids, triterpenoids, steroids, organic acids, phenylpropanoids, and alkaloids, with flavonoids and triterpenoids emerging as the primary bioactive constituents. Pharmacological studies reveal its diverse biological activities, such as haemostatic, antitrichomonal, antibacterial, antiviral, analgesic, immunoregulatory, anti-inflammatory, anticancer, hepatoprotective, and antioxidant effects. Leveraging network pharmacology, researchers have embarked on preliminary inquiries into the interplay among chemical constituents, molecular targets and pathological conditions.

CONCLUSIONS

C. cristata shows significant potential for use in hemostasis, anti-inflammatory, and antimicrobial treatments. Modern research has revealed its diverse chemical composition and pharmacological activities, making it highly valuable for further study. At the same time, it is necessary to find the characteristic components of C. cristata and establish better quality control standards to better explore its therapeutic potential.

Anti-obesity effects of Celosia cristata flower extract in vitro and in vivo

BACKGROUND

The overstoring of surplus calories in mature adipocytes causes obesity and abnormal metabolic activity. The anti-obesity effect of a Celosia cristata (CC) total flower extract was assessed in vitro, using 3T3-L1 pre-adipocytes and mouse adipose-derived stem cells (ADSCs), and in vivo, using high-fat diet (HFD)-treated C57BL/6 male mice.

METHODS

CC extract was co-incubated during adipogenesis in both 3T3-L1 cells and ADSCs. After differentiation, lipid droplets were assessed by oil red O staining, adipogenesis and lipolytic factors were evaluated, and intracellular triglyceride and glycerol concentrations were analyzed. For in vivo experiments, histomorphological analysis, mRNA expression levels of adipogenic and lipolytic factors in adipose tissue, blood plasma analysis, metabolic profiles were investigated.

RESULTS

CC treatment significantly prevented adipocyte differentiation and lipid droplet accumulation, reducing adipogenesis-related factors and increasing lipolysis-related factors. Consequently, the intracellular triacylglycerol content was diminished, whereas the glycerol concentration in the cell supernatant increased. Mice fed an HFD supplemented with the CC extract exhibited decreased HFD-induced weight gain with metabolic abnormalities such as intrahepatic lipid accumulation and adipocyte hypertrophy. Improved glucose utilization and insulin sensitivity were observed, accompanied by the amelioration of metabolic disturbances, including alterations in liver enzymes and lipid profiles, in CC-treated mice. Moreover, the CC extract helped restore the disrupted energy metabolism induced by the HFD, based on a metabolic animal monitoring system.

CONCLUSION

This study suggests that CC total flower extract is a potential natural herbal supplement for the prevention and management of obesity.

Exploring Plants with Flowers: From Therapeutic Nutritional Benefits to Innovative Sustainable Uses

Flowers have played a significant role in society, focusing on their aesthetic value rather than their food potential. This study's goal was to look into flowering plants for everything from health benefits to other possible applications. This review presents detailed information on 119 species of flowers with agri-food and health relevance. Data were collected on their family, species, common name, commonly used plant part, bioremediation applications, main chemical compounds, medicinal and gastronomic uses, and concentration of bioactive compounds such as carotenoids and phenolic compounds. In this respect, 87% of the floral species studied contain some toxic compounds, sometimes making them inedible, but specific molecules from these species have been used in medicine. Seventy-six percent can be consumed in low doses by infusion. In addition, 97% of the species studied are reported to have medicinal uses (32% immune system), and 63% could be used in the bioremediation of contaminated environments. Significantly, more than 50% of the species were only analysed for total concentrations of carotenoids and phenolic compounds, indicating a significant gap in identifying specific molecules of these bioactive compounds. These potential sources of bioactive compounds could transform the health and nutraceutical industries, offering innovative approaches to combat oxidative stress and promote optimal well-being.

Unveiling Alternative Oxidation Pathways and Antioxidant and Cardioprotective Potential of Amaranthin-Type Betacyanins from Spinach-like Atriplex hortensis var. 'Rubra'

A comprehensive oxidation mechanism was investigated for amaranthin-type betacyanins with a specific glucuronosylglucosyl moiety isolated from Atriplex hortensis 'rubra' using liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI-MS/MS) and LC-Quadrupole-Orbitrap-MS (LC-Q-Orbitrap-MS). By employing one-dimensional (1D) and two-dimensional (2D) NMR, this study elucidates the chemical structures of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS)-oxidized celosianins for the first time. These findings demonstrate alternative oxidation pathways for acylated betacyanins compared to well-known betanidin, betanin, and gomphrenin pigments. Contrary to previous research, we uncover the existence of 17-decarboxy-neo- and 2,17-bidecarboxy-xanneo-derivatives as the initial oxidation products without the expected 2-decarboxy-xan forms. These oxidized compounds demonstrated potent free radical scavenging properties. Celosianin (IC50 = 23 μg/mL) displayed slightly higher antioxidant activity compared to oxidized forms, 17-decarboxy-neocelosianin (IC50 = 34 μg/mL) and 2,17-bidecarboxy-xanneocelosianin (IC50 = 29 μg/mL). The oxidized compounds showed no cytotoxic effects on H9c2 rat cardiomyoblasts (0.1-100 μg/mL). Additionally, treatment of H9c2 cells with the oxidized compounds (0.1-10 μg/mL) elevated glutathione levels and exhibited protective effects against H2O2-induced cell death. These findings have significant implications for understanding the impact of oxidation processes on the structures and biological activities of acylated betalains, providing valuable insights for future studies of the bioavailability and biological mechanism of their action in vivo.

Acetaminophen-induced liver injury: Molecular mechanism and treatments from natural products

Acetaminophen (APAP) is a widely used analgesic and antipyretic over-the-counter medicine worldwide. Hepatotoxicity caused by APAP overdose is one of the leading causes of acute liver failure (ALF) in the US and in some parts of Europe, limiting its clinical application. Excessive APAP metabolism depletes glutathione and increases N-acetyl-p-benzoquinoneimide (NAPQI) levels, leading to oxidative stress, DNA damage, and cell necrosis in the liver, which in turn leads to liver damage. Studies have shown that natural products such as polyphenols, terpenes, anthraquinones, and sulforaphane can activate the hepatocyte antioxidant defense system with Nrf2 as the core player, reduce oxidative stress damage, and protect the liver. As the key enzyme metabolizing APAP into NAPQI, cytochrome P450 enzymes are also considered to be intriguing target for the treatment of APAP-induced liver injury. Here, we systematically review the hepatoprotective activity and molecular mechanisms of the natural products that are found to counteract the hepatotoxicity caused by APAP, providing reference information for future preclinical and clinical trials of such natural products.

Chemical composition of the Kaempferia galanga L. essential oil and its in vitro and in vivo antioxidant activities

Introduction

Oxidative stress is closely related to the development of many diseases. Essential oils (EOs) show potent antioxidant activity from natural sources. Kaempferia galanga L. is an important medicine rich in high-value essential oil (KGEO). However, the antioxidant activity of KGEO remains to be fully studied.

Methods

Chemical composition of KGEO was analyzed using gas chromatography-mass spectrometry (GC-MS). The antioxidant activity was determined using the DPPH, ABTS, hydroxyl radical scavenging assays and reducing power assay in vitro. A zebrafish model was used to evaluate the protective effect of KGEO against H2O2-induced oxidative stress damage in vivo.

Results

The major components of KGEO were found to be trans ethyl p-methoxycinnamate (32.01%), n-pentadecane (29.14%) and trans ethyl cinnamate (19.50%). In vitro pharmacological results showed that KGEO had good free radical scavenging capacity in DPPH, ABTS, and hydroxyl radical scavenging assays (IC₅₀ values: 19.77 ± 1.28, 1.41 ± 0.01, and 3.09 ± 0.34 mg/mL, respectively) and weak reducing capacity in the reducing power assay (EC₅₀ value: 389.38 ± 4.07 mg/mL). In vivo zebrafish experiments results indicated that the survival rate and heart rate increased, and ROS generation, cell death, and lipid peroxidation were attenuated after KGEO treatment. In addition, a decrease in malondialdehyde (MDA) levels and increases in superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities were observed in the KGEO-treated groups.

Discussion

This study validated the in vitro and in vivo antioxidant activities of KGEO, which provides a theoretical basis for a profound study of KGEO and its application in the pharmaceutical, food and cosmetic industries.

Metabolomic Approach for Rapid Identification of Antioxidants in Clinacanthus nutans Leaves with Liver Protective Potential

Antioxidants are currently utilized to prevent the occurrence of liver cancer in non-alcoholic fatty liver disease (NAFLD) patients. Clinacanthus nutans possesses anti-oxidative and anti-inflammatory properties that could be an ideal therapy for liver problems. The objective of this study is to determine the potential antioxidative compounds from the C. nutans leaves (CNL) and stems (CNS). Chemical- and cell-based antioxidative assays were utilized to evaluate the bioactivities of CNS and CNL. The NMR metabolomics approach assisted in the identification of contributing phytocompounds. Based on DPPH and ABTS radical scavenging activities, CNL demonstrated stronger radical scavenging potential as compared to CNS. The leaf extract also recorded slightly higher reducing power properties. A HepG2 cell model system was used to investigate the ROS reduction potential of these extracts. It was shown that cells treated with CNL and CNS reduced innate ROS levels as compared to untreated controls. Interestingly, cells pre-treated with both extracts were also able to decrease ROS levels in cells induced with oxidative stress. CNL was again the better antioxidant. According to multivariate data analysis of the 1H NMR results, the main metabolites postulated to contribute to the antioxidant and hepatoprotective abilities of leaves were clinacoside B, clinacoside C and isoschaftoside, which warrants further investigation.

Fucoidan isolated from fermented Sargassum fusiforme suppresses oxidative stress through stimulating the expression of superoxidase dismutase and catalase by regulating Nrf2 signaling pathway

In this study, a fucoidan (SFF-PS-F5) with a molecular weight of 213.33 kDa was isolated from fermented Sargassum fusiforme and the antioxidant activity of SFF-PS-F5 was investigated in vitro in Vero cells and in vivo in zebrafish. SFF-PS-F5 contains 91.68% of fucoidan (72.06% of carbohydrate and 19.62% of sulfate content). SFF-PS-F5 protected hydrogen peroxide (H2O2)-stimulated Vero cells damage by suppressing apoptosis via scavenging intracellular reactive oxygen species (ROS) by up-regulating the intracellular antioxidants. Further results indicated that these actions worked by elevating Nrf2 levels. The in vivo test results displayed that SFF-PS-F5 improved the survival rate by attenuating cell death via suppressing lipid peroxidation by scavenging ROS in H2O2-stimulated zebrafish. These results indicated that SFF-PS-F5 isolated from S. fusiforme possesses potent in vitro and in vivo antioxidant effects and it is a potential ingredient in pharmaceutical, nutraceutical, and cosmeceutical industries.

Protective Effect of Alpinia oxyphylla Fruit against tert-Butyl Hydroperoxide-Induced Toxicity in HepG2 Cells via Nrf2 Activation and Free Radical Scavenging and Its Active Molecules

Alpinia oxyphylla Miq. (Zingiberaceae) extract exerts protective activity against tert-butyl hydroperoxide-induced toxicity in HepG2 cells, and the antioxidant response element (ARE) luciferase activity increased 6-fold at 30 μg/mL in HepG2 cells transiently transfected with ARE-luciferase. To identify active molecules, activity-guided isolation of the crude extract led to four sesquiterpenes (1, 2, 5, 6) and two diarylheptanoids (3 and 4) from an n-hexane extract and six sesquiterpenes (7-12) from an ethyl acetate extract. Chemical structures were elucidated by one-dimensional, two-dimensional nuclear magnetic resonance (1D-, 2D-NMR), and mass (MS) spectral data. Among the isolated compounds, eudesma-3,11-dien-2-one (2) promoted the nuclear accumulation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and increased the promoter property of the ARE. Diarylheptanoids, yakuchinone A (3), and 5'-hydroxyl-yakuchinone A (4) showed radical scavenging activity in 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assays. Furthermore, optimization of extraction solvents (ratios of water and ethanol) was performed by comparison of contents of active compounds, ARE-inducing activity, radical scavenging activity, and HepG2 cell protective activity. As a result, 75% ethanol was the best solvent for the extraction of A. oxyphylla fruit. This study demonstrated that A. oxyphylla exerted antioxidant effects via the Nrf2/HO-1 (heme oxygenase-1) pathway and radical scavenging along with active markers eudesma-3,11-dien-2-one (2) and yakuchinone A (3).

Phenolic, Flavonoid and Antioxidant Capacities Evaluation of Celosia cristata Resulted from Induced Mutation Using Ethyl Methane Sulphonate

<b>Background and Objective:</b> <i>Celosia cristata</i> L. is an ornamental plant that has the potency to be developed as a medicinal plant. The mutation breeding of <i>C. cristata</i> targets the increase of biochemical compounds that are potential as antioxidants. This study aimed to evaluate the phenolic and flavonoid contents and antioxidant activity of the putative mutants of <i>C. cristata</i> in the M1 generation. <b>Materials and Methods:</b> The samples used in this study were flowers and seeds. Induced mutation, using ethyl methane sulphonate (EMS) was used to obtain M1 generation of putative mutants and twelve putative mutants were selected for polyphenol contents analysis composed of total phenolic (TPC), total flavonoid (TFC) and antioxidant activities analysis using two approaches, i.e., 2,2-diphenyl picrylhydrazyl (DPPH) method and ferric reducing antioxidant power (FRAP). <b>Results:</b> This study showed that total phenolics were varied from 11.73-18.06 mg GAE g<sup></sup><sup>1</sup> DW and total flavonoids were varied from 2.34-3.11 mg QE g<sup></sup><sup>1</sup> DW. Meanwhile, the antioxidant activity gain using the DPPH method ranged from 16.43-19.02 μmol TE g<sup></sup><sup>1</sup> DW and the FRAP method ranged from 40.72-59.61 μmol TE g<sup></sup><sup>1</sup> DW. The clustering analysis results formed three clusters with two clusters consisting of potential mutants with higher biochemical content and antioxidant capacities. It was found that total phenolic and flavonoids highly correlated with the antioxidant FRAP. <b>Conclusion:</b> Induced mutation using EMS can increase the diversity of biochemical characters and antioxidant activity of <i>C. cristata</i> and provide potential genetic material with higher chemical content for further development.

The role of natural antioxidants in cisplatin-induced hepatotoxicity

Cisplatin is a potent platinum-based anticancer drug approved by the Food Drug Administration (FDA) in 1978. Despite its advantages against solid tumors, cisplatin confers toxicity to various tissues that limit its clinical uses. In cisplatin-induced hepatotoxicity, few mechanisms have been identified, which started as excess generation of reactive oxygen species that leads to oxidative stress, inflammation, DNA damage and apoptosis in the liver. Various natural products, plant extracts and oil rich in flavonoids, terpenoids, polyphenols, and phenolic acids were able to minimize oxidative stress by restoring the level of antioxidant enzymes and acting as an anti-inflammatory agent. Likewise, treatment with honey and royal jelly was demonstrated to decrease serum transaminases and scavenge free radicals in the liver after cisplatin administration. Medicinal properties of these natural products have a promising potential as a complementary therapy to counteract cisplatin-induced hepatotoxicity. This review concentrated on the protective role of several natural products, which has been proven in the laboratory findings to combat cisplatin-induced hepatotoxicity.

Water and alcohol extracts from Diaphragma juglandis on anti-fatigue and antioxidative effects in vitro and vivo

BACKGROUND

To estimate the anti-fatigue and antioxidative effects of water and alcohol extracts from Diaphragma juglandis (DJ), H₂ O₂ -treated HepG2 cells were used as an in vitro model to determine the total antioxidant capacities of these two extracts, and behavioral tests on mice and biochemical assay were performed via in vivo experiments.

RESULTS

The results indicate that both extracts possess remarkable HepG2 protective capacities and were capable of scavenging 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) similar to vitamin C. Furthermore, they could significantly prolong the bar climbing time and force swimming time, as well as decrease the serum urea nitrogen and increase the lactate dehydrogenase level and glycogen content. These extracts could also improve the activities of total antioxidant capacity, malondialdehyde, superoxide dismutase, catalase and glutathione peroxidase.

CONCLUSION

In conclusion, both water and alcohol extracts from DJ showed good performance with respect to anti-fatigue and could be a potential antioxidant additive in the field of functional foods. © 2020 Society of Chemical Industry.

Immunostimulatory Activity of Polysaccharides Extracted from Celosia cristata Flowers

Macrophages play a major role in innate immune responses by producing a variety of immune mediators and cytokines. The stimulation of macrophages by natural products may lead to an enhanced innate immune system. This study evaluated the immunostimulatory effects of a polysaccharide-rich crude fraction of Celosia cristata L. flowers (CCP) on murine macrophages. CCP treatment induced the production of inducible nitric oxide synthase, cyclooxygenase-2, and cytokines by macrophages. Mechanistically, the activation of mitogen-activated protein kinases, NF-κB and toll-like receptor 4 were found to be associated with the stimulatory functions of CCP. CCP was found to be primarily composed of galacturonic acid and glucose in addition to small amounts of arabinose and galactose. This study demonstrated that CCP may enhance the innate immune responses and potentially improve the immune functions in the body.

Oxidative Stress Evaluation in Ischemia Reperfusion Models: Characteristics, Limits and Perspectives

Ischemia reperfusion injury is a complex process consisting of a seemingly chaotic but actually organized and compartmentalized shutdown of cell function, of which oxidative stress is a key component. Studying oxidative stress, which results in an imbalance between reactive oxygen species (ROS) production and antioxidant defense activity, is a multi-faceted issue, particularly considering the double function of ROS, assuming roles as physiological intracellular signals and as mediators of cellular component damage. Herein, we propose a comprehensive overview of the tools available to explore oxidative stress, particularly in the study of ischemia reperfusion. Applying chemistry as well as biology, we present the different models currently developed to study oxidative stress, spanning the vitro and the silico, discussing the advantages and the drawbacks of each set-up, including the issues relating to the use of in vitro hypoxia as a surrogate for ischemia. Having identified the limitations of historical models, we shall study new paradigms, including the use of stem cell-derived organoids, as a bridge between the in vitro and the in vivo comprising 3D intercellular interactions in vivo and versatile pathway investigations in vitro. We shall conclude this review by distancing ourselves from "wet" biology and reviewing the in silico, computer-based, mathematical modeling, and numerical simulation options: (a) molecular modeling with quantum chemistry and molecular dynamic algorithms, which facilitates the study of molecule-to-molecule interactions, and the integration of a compound in a dynamic environment (the plasma membrane...); (b) integrative systemic models, which can include many facets of complex mechanisms such as oxidative stress or ischemia reperfusion and help to formulate integrated predictions and to enhance understanding of dynamic interaction between pathways.

Celosia cristata Linn. flowers as a new source of nutraceuticals- A study on nutritional composition, chemical characterization and in-vitro antioxidant capacity

This study was undertaken to investigate the nutritional value, chemical characterization and in-vitro antioxidant activity of Celosia cristata Linn. inflorescences, a culturally significant plant of Kashmir valley, India. The results revealed that the flower contained variety of vitamins (A, B-complex, C and E) with Vitamin E (tocopherol) showing the highest concentration. Among minerals, potassium was found to be present in significant amounts, the amino acid and fatty acid profile of the flower was also found to be satisfactory. The antioxidant activity of flower extract was evaluated by various in-vitro analytical methods: DPPH free radical scavenging activity, lipid peroxidation, reducing power, and metal chelating ability. Therefore, the present research brings into focus, the nutritional and antioxidant potential of C. cristata flower and its extract.

Hepatoprotective Effects of Black Pomegranate (Punica granatum L.) Peel Extract on Tert-Butyl Hydroperoxide Induced Oxidative Stress in Rats

Background: Black pomegranate (Punica granatum L.) is a native plant of East Asia, which traditionally has been used as a folk medicine to treat many diseases. Objectives: This research investigated the possible protective effects of hydroalcoholic extract of black pomegranate peel extract (BPPE) on oxidative hepatotoxicity induced by tert-butyl-hydroperoxide (t-BHP) in Wistar rats. Methods: The research was carried out on animals randomly assigned to five groups. In the negative control group, 5 mL/kg of normal saline was given orally. In the positive control group, the same amount of normal saline was administered orally for 5 days, and a single dose of t-BHP was injected on the 6th day. In the test groups, 100, 200, and 400 mg/kg of BPPE was administered orally for 5 days, and then rats were injected with a single dose of t-BHP on the 6th day. The rats were euthanized 24 hours after the last injection. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were determined from blood samples. Liver tissue was sampled to measure the level of glutathione (GSH), malondialdehyde (MDA), and catalase (CAT). Hematoxylin and eosin (H & E) staining and histological examination were performed on partial liver samples preserved in 10% formalin. Results: Pretreatment with BPPE at doses of 200 and 400 mg/kg significantly (P < 0.05) reduced ALT, AST, ALP, and MDA levels and increased GSH level and CAT activity. Histopathology examinations revealed that BPPE significantly improved the histological changes in comparison to the positive control group. Conclusions: The results of this research demonstrate the capability of supplemented BPPE to reduce the oxidative hepatotoxicity induced by t-BHP.

An update on the health benefits promoted by edible flowers and involved mechanisms

The aim of this review is to provide new findings on health effects of edible flowers since 2015. The antioxidant, anti-inflammatory, anti-cancer, hepatoprotective, neuroprotective, anti-diabetic, anti-osteoporosis, anti-obesity, and anti-hypertensive have been reviewed, and the effective concentrations of flower extracts have been summarized. Among all the health benefits mentioned, anti-osteoporosis, anti-obesity, and anti-hypertensive have rarely been mentioned before 2015. Some health benefits mechanisms of edible flowers were discussed frequently after 2015. Some newly found phytochemicals such as polysaccharides were shown to be beneficial to human health. Species of Rosa, Chrysanthemum, and Osmanthus have been reported to exert different health effects on human. For the toxicity studies, the safe level of flower extracts in cell and animal models were at hundreds of parts per million (ppm) level. In consideration of health promoting effects and toxicities of edible flowers, they could serve as potential natural health products for different health benefits.

Protective Effects of Fucoidan Isolated from Celluclast-Assisted Extract of Undaria pinnatifida Sporophylls against AAPH-Induced Oxidative Stress In Vitro and In Vivo Zebrafish Model

Fucoidan is a fucose-enriched polysaccharide, obtained from brown algae, with demonstrated antioxidant properties. However, traditional extraction methods using water or chemical-based extraction methods have reduced yield and produced hazardous by-products. In this study, we isolated fucoidan at a high yield using enzyme-assisted extraction; the Celluclast enzyme assisted extract of Undaria pinnatifida sporophylls (FCUS). To examine the antioxidant properties of FCUS, oxidative stress was induced with 2,2'-azobis (2-methylpropionamidine) dihydrochloride (AAPH) in Vero cells and zebrafish model. FCUS was composed of 30.4% sulfate and 52.3% fucose. Pre-treatment of Vero cells with FCUS dose dependently inhibited AAPH-induced reactive oxygen species (ROS) production. Moreover, FCUS remarkably reduced cell death, ROS generation, and lipid peroxidation production in zebrafish larvae. Overall, these findings indicate that the sulfate-rich fucoidan of FCUS, obtained with an eco-friendly process, could be implemented as a beneficial antioxidant agent in the functional food industry.

Enhancing the antioxidative effects of foods containing rutin and α-amino acids via the Maillard reaction: A model study focusing on rutin-lysine system

Rutin is a bioflavonoid found in many plants and derived foods, accordingly, rutin likely interacts with α-amino acids such as Lys, Ile, His or Glu to give Maillard reaction products (MRPs). The heated rutin-Lys system exhibited highest brown intensity and in vitro antioxidant activities. The 30-50 kDa rutin-Lys fraction had higher in vitro antioxidant activities than the other fractions, and at a dose of 0.4 mg/ml preserved over 90% cell viability for HepG2 cells exposed to H₂ O₂ . The dose-dependent protective effects against H₂ O₂ -induced oxidative stress of the rutin-Lys MRPs may involve the inhibition of reactive oxygen species generation, enhancement of the superoxide dismutase and catalase activities, along with the activation of the Nrf2-dependent pathway and upregulation of phase II antioxidant genes (including NQO1, HO-1, GCLG, and GCLM). PRACTICAL APPLICATIONS: Rutin is widely distributed in vegetables and grains. The Maillard reaction is a common reaction occurring during food processing, and produces Maillard reaction products (MRPs) with distinct processing and biological properties. This study shows that a 30-min thermal treatment at 120°C generates antioxidative MRPs in the rutin-Lys, rutin-His, rutin-Ile and rutin-Glu model systems, which can directly inhibit reactive oxygen species generation and enhance SOD and CAT activities while activating the Nrf2-dependent pathway and upregulating the expression of phase II detoxifying antioxidant genes. Therefore, for food systems containing phenolic antioxidants and proteins (such as rutin and Lys), one may enhance the antioxidant properties of these food systems through a 30-min thermal treatment at 120°C. Also, the resultant rutin-Lys MRPs may be isolated and used as commercial preparations of natural antioxidants.

In Vitro and In Vivo Antioxidant Activities of Polysaccharides Isolated from Celluclast-Assisted Extract of an Edible Brown Seaweed, Sargassum fulvellum

It has been reported that enzymatic digestion of algae could improve the yield and enhance the biological activity compared to water and organic extraction. Our previous research indicated that Celluclast-assisted extract of Sargassum fulvellum (SF) possessed higher carbohydrate content and stronger antioxidant activity compared to water and other enzyme-assisted extracts. In the present study, we evaluated the antioxidant activities of polysaccharides from SF (SFPS) in vitro in Vero cells and in vivo in zebrafish. SFPS was obtained by Celluclast-assisted hydrolysis and ethanol precipitation. Results showed that SFPS contained 74.55 ± 1.26% sulfated polysaccharides and effectively scavenged 1, 1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and alkyl radicals. SFPS significantly and dose-dependently scavenged intracellular reactive oxygen species (ROS) and improved cell viability. Further studies indicated that SFPS reduced apoptotic body formation through downregulation of proapoptotic protein (Bax and cleaved caspase-3) levels and upregulation of antiapoptotic protein (Bcl-xL and PARP) levels in 2,2-azobis(2-amidinopropane) hydrochloride (AAPH)-treated Vero cells. In addition, SFPS showed strong protective effect against AAPH-stimulated oxidative stress in vivo in zebrafish, as demonstrated by the improved survival rate, reduced heart rate, and decrease in ROS, cell death, and lipid peroxidation levels. These results suggest that SFPS possesses strong in vitro and in vivo antioxidant activity and can be a potential ingredient in the pharmaceutical and cosmeceutical industries.

Protective Effects of An Enzymatic Hydrolysate from Octopus ocellatus Meat against Hydrogen Peroxide-Induced Oxidative Stress in Chang Liver Cells and Zebrafish Embryo

Octopus ocellatus, a marine cephalopod distributed in the coast of South Korea, China, Japan and tropical sea, contains high amounts of taurine. In this study, an enzymatic hydrolysate obtained from O. ocellatus meat was evaluated for its antioxidant effects using a human liver cell line and zebrafish embryo model. Enzymatic hydrolysates of the O. ocellatus meat (OOM) were prepared using six different enzymes. Among the enzymatic hydrolysates, Alcalase hydrolysate of OOM (OOMAH) showed the highest scavenging effects against 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS) radicals and hydrogen peroxide (H2O2). Moreover, it showed a high oxygen radical absorbance capacity (ORAC). OOMAH treatment effectively reduced the hydroxyl radical-induced DNA damage. OOMAH reduced the production of reactive oxygen species (ROS) in H2O2-treated hepatocytes without cytotoxicity. Furthermore, OOMAH improved the survival rate and reduced the intracellular ROS levels in H2O2-treated zebrafish embryos. Compositional analysis of amino acids indicated a high content of taurine in OOMAH. Current results suggest that OOMAH possesses antioxidant bioactivities and could provide protective effects against H2O2-induced oxidative stress. Therefore, OOMAH might be used as a potential resource of functional foods.

Study on Betalains in Celosia cristata Linn. Callus Culture and Identification of New Malonylated Amaranthins

Betacyanins and betaxanthins were characterized and determined in an intensely pigmented red-colored callus culture of Celosia cristata L. (Amaranthaceae). A new malonyl derivative, 6'- O-malonyl-amaranthin (celoscristatin) was isolated and identified by spectroscopic and mass spectrometric techniques. Its stereoisomer, 4'- O-malonyl-amaranthin (celoscristatin acyl-migrated), as well as its 15 R diastereomer were also detected in the callus as a result of the malonyl group migration in celoscristatin/isoceloscristatin, respectively. Amaranthin occurs in the callus as the major betacyanin, followed by celoscristatin, betanin, phyllocactin, and other minor betacyanins. The effect of different carbon sources on the growth rates of the Celosia callus as well as on betalains profiles in the callus cultures was studied. High dopamine content in the callus culture was determined and compared with the content in C. cristata inflorescences. The dopamine-based betalain (miraxanthin V) was detected as the main betaxanthin in the callus, however, at a concentration level much lower than that of the identified betacyanins. The studied callus culture of C. cristata can accumulate betalains in amounts which approach the quantities produced by most known high-yielding plant species.

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.

Reformulated meat products protect against ischemia-induced cardiac damage

The protective effects of the antioxidants present in food are of great relevance for cardiovascular health. This study evaluates whether the extracts from reformulated meat products with a reduction in fat and/or sodium content exert a cardioprotective effect against ischemia-induced oxidative stress in cardiomyocytes, compared with non-meat foods. Ischemic damage caused loss of cell viability, increased reactive oxygen species and lipid peroxidation and decreased the antioxidant activity. Pretreatment for 24 h with digested or non-digested extracts from reformulated meat products led to protection against ischemia-induced oxidative damage: increased cell viability, reduced oxidative stress and restored the antioxidant activity. Similar results were obtained using extracts from tuna fish, but not with the extracts of green peas, salad or white beans. These results suggest that reformulated meat products have a beneficial impact in protecting cardiac cells against ischemia, and they may represent a source of natural antioxidants with benefits for cardiovascular health.

Antioxidant potential, total phenolic and total flavonoid contents of Rhododendron anthopogonoides and its protective effect on hypoxia-induced injury in PC12 cells

BACKGROUND

Rhododendron anthopogonoides Maxim, a kind of traditional Tibetan medicine, has been used to remove body heat, body detoxification, cough, asthma, stomachic and swelling, eliminate abundant phlegm and inflammatory for a long time. In the present study, the total phenols and total flavonoid contents as well as antioxidative properties of the crude extract and solvent fractions of R. anthopogonoides were determined using seven antioxidant assays. Additionally, the protective effect of the extracts on hypoxia-induced injury in PC12 cells was also investigated.

METHODS

The content of total flavonoid and total phenolic was determined by the aluminum colorimetric method and Folin-Ciocalteu assay, respectively. In vitro antioxidant study, the effect of the crude extract and solvent fractions on total antioxidant activity, reducing power, DPPH radical scavenging, ABTS radical scavenging, superoxide radical scavenging, hydroxyl radical scavenging and nitric oxide radical scavenging were examined. The correlation between the phenolic and flavonoid content of the extracts and their antioxidant properties also analyzed. Furthermore, the protective effect of extracts on hypoxia-induced damage on PC12 cells was investigated by cell viability, lactate dehydrogenase (LDH) release, malondialdehyde (MDA) production and the activities of antioxidant enzymes.

RESULTS

Our results showed that ethyl acetate and n-butanol fractions had higher content of phenolics and flavonoid compounds than other fractions. Except ABTS radical assay, n-butanol fraction exhibited the strongest antioxidant activity. While the hexane fraction showed the lowest antioxidant activity. Ethyl acetate also presented excellent antioxidant activity, which was just lower than n-butanol fraction. Significant correlation between the phenolic, flavonoid content of the extract and fractions with antioxidant assay excluding ABTS, OH scavenging assay was observed. Moreover, ethyl acetate and n-butanol fractions showed protective effect in PC12 cell under hypoxia condition, while crude extract and water fraction had no protective effect. In contrast, hexane fraction exhibited strong cytoprotective effect. Further study indicated that pretreatment of PC12 cells with ethyl acetate and n-butanol fractions, prior to hypoxia exposure, significantly increased the survival of cells and the activities of SOD, CAT, GSH-Px and T-AOC, as well as reduced the level of LDH and MDA. The gathered data demonstrated that ethyl acetate and n-butanol fractions were able to protect PC12 cells against hypoxia induced injury through direct free radical scavenging and modulation of endogenous antioxidant enzymes.

CONCLUSION

These findings suggested that ethyl acetate and n-butanol fractions of R. anthopogonoides had significant antioxidant activity and could prevent PC12 cells against hypoxia-induced injury. So it might be regarded as an excellent source of antioxidants and had great potential to explore as therapeutic agent for preventing hypoxia related sickness in future.

Antioxidant and hepatoprotective effect of Penthorum chinense Pursh extract against t-BHP-induced liver damage in L02 cells

Penthorum chinense Pursh (P. chinense), a traditional Chinese medicine used by the Chinese Miao minority, has been used to treat liver diseases for a long time. However, the mechanism behind the liver protective effects of P. chinense remains unclear so far. The aim of the present study was to investigate the hepatoprotective effect of P. chinense and its possible mechanism(s). Immortalized normal human normal liver L02 cells were used to evaluate the protective effect of P. chinense aqueous extract against tert-butyl hydroperoxide (t-BHP)-induced liver cell damage. Treatment with P. chinense aqueous extract significantly protected L02 cells from t-BHP-induced cytotoxicity, prevented t-BHP-induced reactive oxygen species (ROS) generation and decreased the percentage of apoptosis by inhibiting the mitochondrial apoptotic pathway. This study demonstrates that P. chinense is a potential hepatoprotective agent in t-BHP-induced liver cell damage, which may benefit the further application of P. chinense in the clinic.

Identification of hepatoprotective xanthones from the pericarps of Garcinia mangostana, guided with tert-butyl hydroperoxide induced oxidative injury in HL-7702 cells

This study identified γ-mangostin from the pericarps of Garcinia mangostana as a potential hepatoprotective agent.