Iron Chelating Activity Research Articles

Effects of green tea extract treatment on erythropoiesis and iron parameters in iron-overloaded β-thalassemic mice.

β-Thalassemia is characterized by ineffective erythropoiesis leading to chronic anemia. Thus, increased iron absorption from the duodenum and via blood transfusions is required to maintain normal blood hemoglobin (Hb) levels and iron chelators in the removal of excessive iron. Certain agents are also needed for the improvement of stress erythropoiesis and iron dysregulation. Green tea extract (GTE), which is rich in epigallocatechin-3-gallate (EGCG), is known to possess radical scavenging and iron-chelating activities. We aimed to assess the effects of green tea extract on erythroid regulators, iron mobilization and anti-lipid peroxidation in the liver, spleen, and kidneys of iron-loaded β-globin gene knockout thalassemic (BKO) mice. Our results indicate that treatments of green tea extract and/or deferiprone (DFP) diminished levels of plasma erythropoietin (EPO) and erythroferrone (ERFE), and consistently suppressed kidney Epo and spleen Erfe mRNA expressions (p < .05) in iron- loaded BKO mice when compared with untreated mice. Coincidently, the treatments decreased plasma ferritin (Ft) levels, iron content levels in the liver (p < .05), spleen (p < .05), and kidney tissues of iron-loaded BKO mice. Furthermore, lipid-peroxidation products in the tissues and plasma were also decreased when compared with untreated mice. This is the first evidence of the orchestral role of green tea extract abundant with epigallocatechin-3-gallate in improving ineffective erythropoiesis, iron dysregulation and oxidative stress in iron-overloaded β-thalassemic mice.

Allium paradoxum extract mediated green synthesis of SeNPs: Assessment of their anticancer, antioxidant, iron chelating activities, and antimicrobial activities against fungi, ATCC bacterial strains, Leishmania parasite, and catalytic reduction of methylene blue

Allium paradoxum extract was used to make selenium nanoparticles (A-SeNPs). The morphological features showed the semi-spherical A-SeNPs with an average diameter of 37.5 nm from the TEM image. The EDX and XRD data confirmed the synthesis of A-SeNPs and FT-IR spectrum observed the importance of bio-functional group existing in A-Extract in the fabrication of A-SeNPs. Also, TG/DTA diagram proved the presence of capping agent on the surface of nanoparticles and the stability of these NPs. Furthermore, the efficiency of Methylene blue (MB) dye degradation obtained 100% for 50, 60, and 70 μl of A-SeNPs (700 μg/ml). The antioxidant activity of A-SeNPs (2.73–87.7 μg/ml) was assessed via DPPH radical scavenging assay, demonstrating an IC50 value of 92.55 ± 1.35 μg/ml. In the Ferrozine assay, A-SeNPs (1.33–41.66 μg/ml) showed potent iron chelation activity with an IC50 value of 24.8 ± 0.73 μg/ml. In the antibacterial investigation, A-SeNPs (0.17–175 μg/ml) demonstrated the highest activity against P. aeruginosa and A. baumannii. Besides, our nanoparticles had high antifungal activity against several fungi strains and also presented IC50 value of 35.49 μg/ml against promastigotes. A-SeNPs exhibited anticancer activity on MCF-7 and AGS cells with IC50 values of 33.97 and 22.33 μg/ml, respectively. Therefore, synthesized SeNPs presented high potential in various applications.

Chromone-based monoamine oxidase B inhibitor with potential iron-chelating activity for the treatment of Alzheimer’s disease

Based on the multitarget-directed ligands (MTDLs) strategy, a series of chromone-hydroxypyridinone hybrids were designed, synthesised, and evaluated as potential multimodal anti-AD ligands. Prospective iron-chelating effects and favourable monoamine oxidase B (MAO-B) inhibitory activities were observed for most of the compounds. Pharmacological assays led to the identification of compound 17d, which exhibited favourable iron-chelating potential (pFe3+ = 18.52) and selective hMAO-B inhibitory activity (IC50 = 67.02 ± 4.3 nM, SI = 11). Docking simulation showed that 17d occupied both the substrate and the entrance cavity of MAO-B, and established several key interactions with the pocket residues. Moreover, 17d was determined to cross the blood–brain barrier (BBB), and can significantly ameliorate scopolamine-induced cognitive impairment in AD mice. Despite its undesired pharmacokinetic property, 17d remains a promising multifaceted agent that is worth further investigation.

Quality characteristics and antioxidant activities of Korean traditional rice and quinoa‐based wine “Makgeolli”

AbstractBackground and ObjectivesMakgeolli is a traditional Korean rice wine that is brewed by fermenting a mixture of steamed rice and Nuruk. Quinoa products contain polyphenols, including phenolic acids, flavonoids, and tannins, which make up bioactive secondary plant metabolites that contribute to diverse physiological properties, such as antimicrobial, antioxidant, and antitumor activities. The preparation of rice‐based Makgeolli (RM) and quinoa‐added Makgeolli (QM) were obtained by combining rice and quinoa in ratios 1:1 (RM; control: without supplement). This study sought to assess the physicochemical, microbiological, antioxidant, and taste tests of RM and QM during a 6‐day fermentation period.FindingThe alcohol content increased steadily until Day 6 (10.7%–10.3%). From the start of fermentation to Day 2 of fermentation, the number of lactic acid bacteria (LAB) in RM and QM increased rapidly (p &lt; .05), with no significant increase thereafter (p &gt; .05). 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2,2‐azino‐bis(3‐ethylbenzthiazoline‐6‐sulfonic acid) (ABTS) radical scavenging activities were significantly (p &lt; .05) higher in QM (DPPH: 81.01%, ABTS: 91.46%) than in RM (DPPH: 43.65%, ABTS: 53.85%). The average result of iron(II) chelating activity for RM was 39.81%, while for QM was 47.09%. Moreover, superoxide dismutase scavenging activity of both RM and QM were 41.07% and 56.23%, respectively. There were no significant differences in color, smell, appearance, and overall acceptability between RM and QM (p &gt; .05). However, taste values were significantly higher (p &lt; .05) in QM than in RM (5.9 vs. 4.3).ConclusionMakgeolli supplemented with quinoa owing to its good physicochemical and microbiological characteristics, including high antioxidant properties and good consumer acceptance.

Pluripharmacological potential of Mascarene endemic plant leaf extracts

Tropical forests of the islands of the West Indian Ocean region, have a rich and diverse collection of unique plants containing a multitude of chemical scaffolds that can potentially be developed into medicinal agents. Till date, endemic plants from the Mascarene Archipelago have been undervalued but they hold significant economic and biomedical potential. Hence, to better gauge the pharmacological potential of Mascarene Archipelago flora, the bioactivities of fourteen selected endemic species were investigated. Leaf extracts from species within the Ebeneceae, Myrtaceae, Sapotaceae and Combretaceae families were prepared via organic solvent extraction and evaluated for their polyphenolic content, antioxidant, antiproliferative, anti-tyrosinase, anti-elastase and antiplasmodial activities. The highest polyphenol content was observed in Terminalia bentzoë (385.0 ± 24.1 mg gallic acid equivalent (GAE)/g) followed by Sideroxylon sessiliflorum (340.5 ± 13.4 mg GAE/g) (p < 0.05). Each extract showed dose-dependent metal chelating and free radical scavenging activity, however, T. bentzoë demonstrated the most significant (p < 0.05) antioxidant activity in terms of ferric reducing antioxidant power, iron chelating activity, superoxide anion and nitric oxide free radical scavenging activity, followed by Syzygium glomeratum. Eugenia orbiculata and E. pollicina exhibited the highest anti-tyrosinase activity, while Diospyros chrysophyllos showed noteworthy anti-elastase activity. Terminalia bentzoë further showed potent dose-dependent antiplasmodial activity against Dd2lucPlasmodium falciparum with an EC50 value of 6.7 μg/mL. Moreover, the extracts showed moderate to low toxicity against the non-tumorigenic kidney (Vero) and keratinocyte (HaCat) cell lines. The findings highlight the potential of T. bentzoë and S. glomeratum as alternative sources of pharmaceutical compounds.

Modelling and optimization of polyphenol and antioxidant extraction from Rumex hastatus by green glycerol-water solvent according to response surface methodology

Rumex hastatus (RH) is an edible wild herb abundantly distributed in many parts of the world. With the increasing realization of the environmental threats corresponding to the use of conventional organic solvents, the realization to explore efficient green solvents for the extraction of valuable natural products from plants is increasing. The present project, therefore, aimed to discover an optimized efficient and green process for obtaining antioxidant phytochemicals from R. hastatus using aqueous glycerol as a green and low-cost extraction medium. For modelling and optimization according to RSM (response surface methodology), the independent factors were glycerol concentration, temperature and time, and the responses included TPC (total phenolic content), TFC (total flavonoid content), and anti-radical activity (ARA) and iron chelating activity (ICA). The predicted optimum conditions were 52.155% glycerol concentration, 41.303 min extraction time and 50 °C extraction temperature with the predicted values for TPC, TFC, ARA and ICA as 21.65 mg GA/g DW, 95.78 mg RE/g DW, 84.93% and 46.47%, respectively. For responses, well-fitted quadratic models were suggested. Thus, aqueous glycerol is an efficient, green, and cost-effective solvent and its around 50% solution can effectively be used as an extracting medium for antioxidants from R. hastatus. The discovered model should be viable for large scale extraction of bioactive compounds from this plant.

Microencapsulation upholds biological activities of sheep whey hydrolysates and protects against in vitro gastrointestinal digestion

Recycling of dairy by-products as sources of bioactive compounds is an interesting approach for improving sustainable food production. This study aimed to encapsulate a sheep whey hydrolysate (SWH) with antioxidant and antihypertensive properties, produced by a novel proteinase P7. SWH encapsulation was achieved by spray-drying and freeze-drying methods using prebiotic gum Arabic as the encapsulating material. The morphology, colour, moisture, water activity, hygroscopicity, antioxidant and antihypertensive properties, and in vitro digestion of the microcapsules were evaluated. Spray-drying process produced powders with better characteristics as compared with freeze-drying, showing 3.9% moisture, 18.9% hygroscopicity, highest ABTS radical scavenging (65.7%) and iron chelating (78.4%) activities and 70.1% inhibition of the angiotensin I-converting enzyme. Additionally, these biological properties were not affected during simulated gastrointestinal conditions. SWH encapsulation may be an interesting strategy for valorisation of dairy industry by-products, as an ingredient for development of functional foods and potentially increasing nutritional value and shelf life.

Phenolic content and antioxidant activity of hydromethanolic and aqueous extracts of aerial parts of Phlomis crinita.

Phlomis crinita is a plant species of the family Lamiaceae including more than 100 perennial herbs, shrubs, and sub-shrubs species native to the Mediterranean, Central Asia, and India. This species is commonly a good natural source of various secondary metabolites. Therefore, the present study was conducted to determine phenolic content and antioxidant activity of hydromethanolic (PC ME) and aqueous extracts (PC AQE) of aerial parts of P. crinita. Total polyphenols, flavonoids and tannins were quantified, respectively by the methods of Folin-Ciocalteu reagent, aluminum trichloride (AlCl3) and Bate-Smith method. The in vitro antioxidant activity was assessed using DPPH and ABTS•+ radical scavenging, β-carotene-linoleic acid, reducing power and ferrous ion chelating activity assays. PC ME showed high level of tannins (132,13 ±0.68 µg TAE/mg extract) and total phenolic content (82.71±0.79 µg GAE/mg extract), in addition a marked inhibiting oxidation activity of β-carotene/ linoleic acid (74.10%) was observed. Results showed also a higher iron-chelating activity of PC ME (0.20 mg/mL) compared to PC AQE (0.046 mg/mL). The plant extracts revealed a significant antioxidant activity as evidenced by the DPPH and ABTS radical scavenging activity (IC50 = 0.103 mg/mL for PC ME and 0.144 mg/mL for PC AQE) for DPPH assay and (IC50 = 0.0130 mg/mL for PC ME and 0.0187 mg/mL for PC AQE) , as well as the PC ME exhibits higher reducing power (IC50 =0.288mg/mL) than PC AQE (0.296 mg/mL). As a result, P.crinita is suggested as a promising and effective therapeutic medicinal plant for the treatment of several diseases.

Melatonin: Potential avenue for treating iron overload disorders.

Iron overload as a highly risk factor, can be found in almost all human chronic and common diseases. Iron chelators are often used to treat iron overload; however, patient adherence to these chelators is poor due to obvious side effects and other disadvantages. Numerous studies have shown that melatonin has a high iron chelation ability and direct free radical scavenging activity, and can inhibit the lipid peroxidation process caused by iron overload. Therefore, melatonin may become potential complementary therapy for iron overload-related disorders due to its iron chelating and antioxidant activities. Here, the research progress of iron overload is reviewed and the therapeutic potential of melatonin in the treatment of iron overload is analyzed. In addition, studies related to the protective effects of melatonin on oxidative damage induced by iron overload are discussed. This review provides a foundation for preventing and treating iron homeostasis disorders with melatonin.

Exopolysaccharide produced by Lactiplantibacillus plantarum RO30 isolated from Romi cheese: characterization, antioxidant and burn healing activity

Microbial exopolysaccharides (EPSs) extracted from lactic acid bacteria (LAB) are generally recognized as safe. They have earned popularity in recent years because of their exceptional biological features. Therefore, the present study main focus was to study EPS-production from probiotic LAB and to investigate their antioxidant and burn wound healing efficacy. Seventeen LAB were isolated from different food samples. All of them showed EPS-producing abilities ranging from 1.75 ± 0.05 to 4.32 ± 0.12 g/l. RO30 isolate (from Romi cheese) was chosen, due to its ability to produce the highest EPS yield (4.23 ± 0.12 g/l). The 16S rDNA sequencing showed it belonged to the Lactiplantibacillus plantarum group and was further identified as L. plantarum RO30 with accession number OL757866. It displayed well in vitro probiotic properties. REPS was extracted and characterized. The existence of COO−, OH and amide groups corresponding to typical EPSs was confirmed via FTIR. It was constituted of glucuronic acid, mannose, glucose, and arabinose in a molar ratio of 2.2:0.1:0.5:0.1, respectively. The average molecular weight was 4.96 × 104 g/mol. In vitro antioxidant assays showed that the REPS possesses a DPPH radical scavenging ability of 43.60% at 5 mg/ml, reducing power of 1.108 at 10 mg/ml, and iron chelation activity of 72.49% and 89.78% at 5 mg/ml and 10 mg/ml, respectively. The healing efficacy of REPS on burn wound models in albino Wistar rats showed that REPS at 0.5% (w/w) concentration stimulated the process of healing in burn areas. The results suggested that REPS might be useful as a burn wound healing agent.

In vitro antioxidant activity of Lippia adoensis Var. Koseret, Thymus schimperi Ronniger and Rosmarinus officinalis Leaf extracts and their effects on oxidative stability of ground raw beef meat during refrigeration storage

Rosmarinus officinalis,Thymus schimperi Ronniger, and Lippia adoensis var. koseret, locally known as Rosemary, Tosign, and Koseret respectively are widely used dietary herbs in Ethiopia. In this study, the antioxidant activity and effect of Rosemary, Tosign, and Koseretethanol (80% v/v) extract on lipid oxidation of ground beef during storage were studied. Folin-Ciocalteu and aluminium chloride were used to determine total phenolic content (TPC) and total flavonoid content (TFC), respectively. Antioxidant activities of herbs were evaluated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging, ferric reducing power and iron chelating activities. The peroxide and thiobarbituric acid reactive substances assays were used to evaluate the ability of the extracts to prevent lipid peroxidation in ground beef stored at 4°C. Tosign extract had highest TPC (70.93±1.53 mg GAE/g) and TFC (16.94±0.12 mg CE/g). Also, Tosign had the strongest effect of DPPH scavenging (IC50 = 33.35±1.56µg/mL) and ferric reducing power (IC50 = 175.71±1.03 µg/mL). But the strongest iron-chelating activity was observed in Rosemary extract (IC50 = 160.24±2.55 µg/mL). Minimum peroxide value (0.185±0.09 milli equivalent peroxide/kg of beef) and the highest thiobarbituric acid reactive substances (80.20±20%) were recorded for ground beef treated with Rosemary at the end of storage days. In conclusion, these herbs are very effective antioxidants comparable to butylated hydroxytoluene. Thus, they could be a good substitution to synthetic antioxidants used in food preservation.

Hematological Profile of Iron Overload in Rats Administered with Fruit Extract of Mahkota Dewa (Phaleria macrocarpa)

Background: Repeated blood transfusions lead to an accumulation of iron that exceeds the body's iron storage capacity. Free iron is able to catalyze the formation of hydroxyl radicals that cause oxidative damage and cell death. The use of iron chelating medicines for iron chelation therapy is limited by side effects. Mangiferin is a natural bioactive compound with iron chelating and antioxidant activity. Mahkota dewa is a plant native to Indonesia that contains mangiferin. Objectives: The aim of this study was to evaluate the effect of mahkota dewa fruit extract administration on hematological profile of iron overload rats. Material and Methods: Thirty rats were divided into 6 groups: normal rats (N), iron overload rats (IO), iron overload rats rats given deferiprone (D), mangiferin (M), Mahkota dewa fruit extract at a dose of 100 mg/kg BW (PM1), or 200 mg/kg BW (PM2). Rats were given injection of iron sucrose 15 mg every 3-4 days for 8 weeks. At week 8, rats were sacrificed. Hematological analysis was performed in this study. Results: Iron overload condition caused by iron sucrose injection did not cause statistically significant changes in the haematological profile. Likewise, the administration mahkota dewa fruit extract at a dose of 100 or 200 mg/kg BW did not cause changes in the hematological profile. Conclusions: The administration of mahkota dewa fruit extract did not alter hematological profile of iron oveload rats.

The molecular and functional characterization of ferritins in the hard tick Hyalomma rufipes

BackgroundThe protein ferritin, which plays an important role in the maintenance of iron homeostasis, is indispensable for iron detoxification, resistance to oxidative stress and innate immunity. Ticks, which are obligate blood-sucking ectoparasites, have to deal with a large amount of iron when they take a blood meal.MethodsSequence analysis was undertaken using bioinformatics. A recombinant (r) expression vector, rferritin, was constructed for a prokaryotic expression system. A quantitative polymerase chain reaction platform was used to detect the spatial and temporal expression patterns of target genes and their responses to a low temperature environment. Knockdown of the ferritin genes through RNA interference was used to analyze their effects on physiological parameters of ticks.ResultsTwo ferritin genes, HrFer1 and HrFer2, were cloned from the tick Hyalomma rufipes. Their open reading frames are 519 base pairs (bp) and 573 bp in length, and number of coding amino acids 170 and 190, respectively. The phylogenetic tree showed that HrFer1 and HrFer2 have a close evolutionary relationship with the H subunit of ferritin. In vitro experiments showed that rHrFer1 and rHrFer2 had concentration-dependent iron chelating activity. The relative expression of the two ferritin genes was higher in the ovary and midgut of H. rufipes. RNA interference results demonstrated that HrFer1 and HrFer2 expression had a significant effect on engorged body weight, number of eggs laid, and mortality of H. rufipes, and that HrFer2 also had a significant effect on feeding duration. Furthermore, the relative expression of ferritin decreased significantly in a low temperature environment, suggesting that HrFer1 and HrFer2 play a regulatory role in the cold stress response of H. rufipes.ConclusionsThe results of the present study improve our understanding of the involvement of ferritins in tick blood-feeding.Graphical

Evaluation of erythrocyte viability, antioxidant capacity and antiplasmodial activity induced by alkaloid extract of Phyllanthus amarus

Introduction: The production of large amounts of reactive oxygen species in severe malarial infection is due to parasite invasion to erythrocytes. Malaria resistance to medication has left malaria-endemic countries with no alternate source of medications but traditional medicine. One of such plants utilized by traditional healers is Phyllanthus amarus. Therefore, this study aims at ascertaining the antiplasmodial and cytotoxic activities of P. amarus and its specific actions on retaining erythrocyte viability and antioxidant activity. Methods: Antiplasmodial and erythrocyte viability activities were determined in vitro via parasite suppression and tetrazolium-based colorimetric assays, respectively. Antioxidant capacity was determined by measuring extract’s ability to inhibit lipid peroxidation, scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide ions, reduce iron(III) ions, and chelate iron in vitro using documented methods. Results: Alkaloid extracts of P. amarus showed great antiplasmodial activity (IC50=0.52μg/mL) and low cytotoxic activity (CC50=54.95 μg/mL). Erythrocyte viability assay showed the minimal impact of the extract on the uninfected erythrocytes but improved viability of the infected RBC in a dose dependent manner, and antioxidant activity manifested mainly in its iron chelating activity (EC50=0.34 μg/mL). Conclusion: This study suggests that the alkaloid extract of P. amarus has significant antiplasmodial and antioxidant activities. These activities promoted the repair of parasite-induced free radical damage to the erythrocyte membrane but distorted the parasites redox balance and defense mechanism, and hence survival rate as indicated by the parasite suppression associated with alkaloid extract treatment of malarial infection.

Optimization of ultrasound-assisted extraction of valuable compounds from fruit of Melia azedarach with glycerol-choline chloride deep eutectic solvent

A green and cost-effective method was explored to extract phenolics, flavonoids, antioxidant, and iron chelating agents from fruits of medicinal tree Melia azedarach using natural deep eutectic solvent (NADES) and ultrasound treatment. NADES consisting of glycerol and choline chloride was prepared and used for extraction. Optimization of extraction was done as per response surface methodology using Box-Behnken design with three factors. The strategy proved successful with considerable extraction of total phenols, total flavonoids, radical scavengers, and iron chelators. Optimized conditions were found to be temperature (46.4 °C), ultrasound amplitude (100%; 130 Watt power) and DES concentration (50%) with predicted total phenols 9.154 mg Gallic acid equivalents/g dried weight (DW), total flavonoids 21.880 mg Rutin equivalents/g DW, iron chelating activity 33.254%, and anti-radical activity 51.166%. Validation experiments resulted in minimal errors (3.87–0.61%) that substantiated the proposed model. The model may be used in designing large scale extraction of phenolics and other antioxidant compounds from the fruit of M. azedarach using the green and low-cost glycerol-choline chloride NADES and ultrasound mediation.

Comparative Metabolomics Reveals a Bifunctional Antibacterial Conjugate from Combined-Culture of Streptomyces hygroscopicus HOK021 and Tsukamurella pulmonis TP-B0596.

To investigate the potential for secondary metabolite biosynthesis by Streptomyces species, we employed a coculture method to discover natural bioactive products and identified specific antibacterial activity from a combined-culture of Streptomyces hygroscopicus HOK021 and Tsukamurella pulmonis TP-B0596. Molecular networking using ultrahigh performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS) data revealed a specific clade of metabolites in this combined-culture that were not detected in both monocultures. Using the chemical profiles, a previously unidentified conjugate between FabF inhibitor and catechol-type siderophore was successfully identified and named harundomycin A. Harundomycin A was a conjugate between the 2,4-dihydroxy-3-aminobenzoate moiety of platensimycin and N,N'-bis(2,3-dihydroxybenzoyl)-O-seryl-cysteine (bisDHBA-Ser-Cys) with a thioester linkage. Along with the production of harundomycin A, platensimycin, its thiocarboxylic acid form thioplatensimycin, enterobactin, and its degradation product N,N'-bis(2,3-dihydroxybenzoyl)-O-l-seryl-dehydroalanine (bisDHBA-Ser-Dha) were also induced in the combined-culture. Genomic data of S. hygroscopicus HOK021 and T. pulmonis TP-B0596 indicated that strain HOK021 possessed biosynthetic gene clusters for both platensimycin and enterobactin, and thereby revealed that T. pulmonis stimulates HOK021 and acts as an inducer of both of these metabolites. Although the harundomycin A was modified by bulky bisDHBA-Ser-Cys, responsible for the binding to the target molecule FabF, it showed a similar antibacterial spectrum to platensimycin, including against methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, suggesting that the pharmacophore is platensimycin. Additionally, Chrome Azurol S assay showed that harundomycin A possesses ferric iron-chelating activity comparable to that of enterobactin. Our study demonstrated the transformation of existing natural products to bifunctional molecules driven by bacterial interaction.

Optimization of solvent-free microwave-assisted extraction of antioxidant compounds from Lagenaria siceraria fruit by response surface methodology

Abstract Lagenaria siceraria (bottle gourd) fruit is highly celebrated for its nutritional as well as therapeutic properties. The present study was undertaken with the aim of exploring an efficient green solvent-free microwave-assisted extraction method for bioactives from this fruit. Optimization was done according to response surface methodology (RSM), where microwave power (W) and time (s) were independent factors, and percent extraction yield, total phenolic content (TPC), total flavonoid content (TFC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant potential (FRAP) and iron chelating activity (ICA) were the responses. TPC, TFC, DPPH radical scavenging activity, FRAP and ICA were highest at 480 W and 60 s. The TPC was 288.9 mg GAE · g−1 DW (milligram gallic acid equivalent per gram dry weight), TFC was 214.1 mg RE · g−1 (rutin equivalent per gram DW), anti-radical activity was 32.96%, FRAP was 289.7 mg AAE · g−1 (mg ascorbic acid equivalents per gram) and ICA was 19.52%. The results of the study thus demonstrate that the solvent-free microwave-assisted extraction method, which utilised an optimum power of 480 W and a time of 60 s, is an effective and green method for extraction of antioxidant compounds from bottle gourd fruit.

Evaluation of the antioxidant effect of a phytocomplex addition in clean label pork salami enriched in n-3 PUFA

Control and n-3 PUFA enriched raw material was used to manufacture clean label and conventional salami; the former were added with a phytocomplex having iron chelating, DPPH, and FRAP activity, obtained from olive vegetation water, oregano, green tea and blueberry leaves, and with acerola powder. Salami were dried at 3 ± 1 °C until an established decrease in the combined pH and aw values, while only the conventional ones underwent a standard process. In the cold dried salami pH changes, aw and weight decrease were delayed; the phytocomplex contributed to lower the pH, and to prevent lipid and protein oxidation, despite the n-3 PUFA enrichment and heme iron release due to nitrite removal. TBARS and protein carbonyls were the highest in the nitrite-added salami undergoing cold and standard drying, respectively. The oxidation marker MDA tended to increase in the simulated digests of salami n-3 PUFA enriched or subjected to cold drying.

Quantitative Structure-Activity Relationship, Ontology-Based Model of the Antioxidant and Cell Protective Activity of Peat Humic Acids.

Peat humic acids are well known for their wide range of biological effects which can be attributed to the complex chemical structure of naturally occurring humic substances. One of the promising tools is an ontology-based quantitative analysis of the relationship between physical and chemical parameters describing a chemical structure of peat humic acids and their biological activity. This article demonstrates the feasibility of such an approach to estimate the antioxidant and cell protective properties of the peat humic acids. The structural parameters of the peat humic acids were studied by electronic, fluorescence, infrared, 13C-NMR spectroscopy, titrimetric analysis, elemental C,H,N, and O- analysis, and gel chromatography. Antioxidant and antiradical activities were assessed by physicochemical methods of analysis: electronic paramagnetic resonance, cathodic voltammetry, ABTS•+ scavenging, assay of DPPH radical-scavenging activity, assay of superoxide radical-scavenging activity, iron chelating activity, and scavenging of hydroxyl radicals. Cytoprotective activity was evaluated by the neutral red-based cytotoxicity test in 3T3-L1 cell culture in a wide range of concentrations. Assessment of intracellular ROS production was carried out using a 2,7-dichlorodihydrofluoresceindiacetate (DCFDA) fluorescent probe. Intracellular ROS production was induced using two common prooxidants (tert-butyl hydroperoxide, Fe2+ ions). We suggested an ontology-based model for the antioxidant and cytoprotective activity of humic acids based on experimental data and numerical models. This model establishes the way to further research on the biological effects of humic acids and provides a useful tool for numerical simulation of these effects. Remarkable antioxidant and cell protective activity of humic acids makes them a promising natural source of new pharmaceutical substances that feature a wide range of biological effects.

Identification of high iron–chelating peptides with unusual antioxidant effect from sea cucumbers and the possible binding mode

Iron deficiency anemia (IDA) is a common nutritional disease affecting 2 billion people. To develop a new iron-fortified food, we designed a novel type of iron-chelating peptide [Sea cucumbers peptides (SCP)–Fe] from sea cucumbers. SCP can chelate ferrous ions. The neutral protease hydrolysate have the highest iron chelating activity (117.17 ± 2.62 mg/g). Single factors including pH, material ratio, and molecular weight, had a significant effect on the iron chelating activity. The characterization of the SCP–Fe chelate revealed a loose and blocky structure with increased particle size. The amino acid composition, peptide identification and molecular docking indicated that Asp, Glu, Gly and Pro played an important role in binding to ferrous ions. After chelation, SCP–Fe chelate had dual nutrition effects of stronger radical scavenging ability and potential high-efficiency iron supplementation ability. These results might provide insights into the methods for developing functional foods such as iron-fortified seafood.