Characterization of Protein Hydrolysates from Fish Discards and By-Products from the North-West Spain Fishing Fleet as Potential Sources of Bioactive Peptides.

Fish discards and by-products can be transformed into high value-added products such as fish protein hydrolysates (FPH) containing bioactive peptides. Protein hydrolysates were prepared from different parts (whole fish, skin and head) of several discarded species of the North-West Spain fishing fleet using Alcalase. All hydrolysates had moisture and ash contents lower than 10% and 15%, respectively. The fat content of FPH varied between 1.5% and 9.4% and had high protein content (69.8-76.6%). The amino acids profiles of FPH are quite similar and the most abundant amino acids were glutamic and aspartic acids. All FPH exhibited antioxidant activity and those obtained from Atlantic horse mackerel heads presented the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, reducing power and Cu2+ chelating activity. On the other hand, hydrolysates from gurnard heads showed the highest ABTS radical scavenging activity and Fe2+ chelating activity. In what concerns the α-amylase inhibitory activity, the IC50 values recorded for FPH ranged between 5.70 and 84.37 mg/mL for blue whiting heads and whole Atlantic horse mackerel, respectively. α-Glucosidase inhibitory activity of FPH was relatively low but all FPH had high Angiotensin Converting Enzyme (ACE) inhibitory activity. Considering the biological activities, these FPH are potential natural additives for functional foods or nutraceuticals.

Optimization of ultrasound assisted extraction of abalone viscera protein and its effect on the iron-chelating activity.

This study aims to investigate effects of ultrasound assisted extraction on the abalone viscera protein extraction rate and iron-chelating activity of peptides. The optimal conditions for ultrasound assisted extraction by response surface methodology was at sodium hydroxide concentration 14 g/kg, ultrasonic power 428 W and extraction time 52 min. Under the optimal conditions, protein extraction rate was 64.89%, compared with alkaline extraction of 55.67%. The iron-chelating activity of peptides affected by ultrasound technology was further evaluated by iron-chelating rate, FTIR spectroscopy and LC-HRMS/MS. Alcalase was the suitable enzyme for the preparation of iron-chelating peptides from two abalone viscera proteins, showing no significant difference between their iron-chelating rate of 16.24% (ultrasound assisted extraction) and 16.60% (alkaline extraction). Iron binding sites from the two hydrolysates include amino and carboxylate terminal groups and peptide bond of the peptide backbone as well as amino, imine and carboxylate from side chain groups. Moreover, 24 iron-chelating peptides were identified from hydrolysate (alcalase, ultrasound assisted extraction), which were different from the 27 iron-chelating peptides from hydrolysate (alcalase, alkaline extraction). This study suggests the application of ultrasound technology in the generation of abalone viscera-derived iron-chelating peptides which have the ability to combat iron deficiency.

The iron chelating activity of Gundelia tournefortii in iron overloaded experimental rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Gundelia tournefortii is a member of the Asteraceae (Compositae) family which is widely consumed as edible plant in the Eastern Mediterranean. In folkloric medicine, it is used for the treatment of various diseases and conditions, including pain, liver diseases, kidney stones and inflammations. AIM OF THE STUDY: Recently, many commoners use this plant as adjuvant therapy for treating symptoms associated with liver diseases and thalassemia. Thus, the present study was conducted to evaluate, biochemically, the iron chelating activity of G. tournefortii methanolic extract in iron overloaded rats. MATERIALS AND METHODS: Fifty Wister male rats were divided into five groups: one group was a healthy control, while iron overload was induced in the other four groups by 100 mg/kg iron-dextran. Of these, one group was left untreated as a control, while the other three groups were treated with 50 mg/kg deferoxamine, 100 mg/kg and 200 mg/kg of G. tournefortii methanolic extract, respectively. The total flavonoid and phenolic contents of the methanolic extract were estimated. The biochemical assessment was performed by measuring blood levels of iron, ferritin, liver biomarkers (ALT, ALP and AST), cardiac biomarkers (CPK and LDH) and lipid profile. RESULTS: Not only the blood levels of iron, ferritin, liver biomarkers and cardiac biomarkers were reduced significantly by G. tournefortii methanolic extract, but also the lipid profile was improved. This clearly supports the chelating activity of G. tournefortii and its hepatoprotective and cardioprotective effects in iron overloaded rats. CONCLUSIONS: This highlights the value of medicinal plants as alternative therapies for iron overload conditions such as thalassemia.

Structural characterization of a low-molecular-weight polysaccharide from Angelica pubescens Maxim. f. biserrata Shan et Yuan root and evaluation of its antioxidant activity.

A novel heteropolysaccharide with about twenty sugar residues named DF80-2 was obtained from Angelica pubescens Maxim. f. biserrata Shan et Yuan root, one of the most widely used traditional Chinese medicines for thousands of years in China. The possible structure of DF80-2 was proposed considering the comprehensive results of physicochemical properties, methylation analysis, and 1D/2D NMR spectroscopy, which showed that its main chain was composed of (1→3)-, and (1→4)-linked-α-d-Glcp, (1→4)-linked-ß-d-Galp, (1→6)-linked-α-d-Manp, and (1→3)-linked-α-l-Araf, and the branch was present as the α-d-Glcp-(1→3)-ß-d-GalpA disaccharides stretched from O-6 position of (1→4)-linked-α-d-Glc moiety in the main chain. Congo red analysis, scanning electron microscopy and atomic force microscopy showed that DF80-2 possessed a triple helical conformation, and its branched monomers were interlaced with one another forming a regular network structure. DF80-2 exhibited antioxidant activity by effectively scavenging DPPH, and hydroxyl radicals, and chelating ferrous ions.

Characteristics and bioactive properties of mannooligosaccharides derived from agro-waste mannans.

Mannooligosaccharides (MOS) were derived using Aspergillus oryzae ß-mannanase (ManAo) from different mannan-rich agro-wastes, palm kernel cake (PKC), guar gum and copra meal (CM). Guar gum (GG) released higher amount of MOS (56.31% w/w) from which purification of mannobiose (0.68 mg) and mannotriose (1.26 mg) was demonstrated using size-exclusion chromatography. FTIR analysis of mannan hydrolysates showed characteristic peaks in 1200-900 cm-1 region indicating the presence of MOS. 1H &13C NMR spectra showed presence of anomeric sugar forms of MOS in different mannan hydrolysates. MOS from locust bean gum and guar gum had both α- and ß-anomers while PKC and CM had only α-anomer. Growth promotional activities of different MOS were demonstrated using two probiotic Lactobacilli. Besides, enzymatically derived MOS also showed metal (Fe2+) chelating and anti-oxidant activities, wherein best anti-glycating agent was evaluated as MOS from PKC. PKC derived MOS showed highest cytotoxicity (74.19%) against human colon adenocarcinoma cell line (Caco-2). This study demonstrated the prebiotic potential of agro-waste derived MOS and possibility of their utilization as a functional food ingredient.

Characterization and antioxidant activities of intracellular polysaccharides from Agaricus bitorquis (QuéL.) Sacc. Chaidam ZJU-CDMA-12.

The antioxidant activities of polysaccharides from the fruiting body (PFB), extracellular polysaccharides (EPS) and intracellular polysaccharides (IPS) from Agaricus bitorquis (QuéL.) Sacc. Chaidam ZJU-CDMA-12 in vitro were compared. IPS showed stronger antioxidant activities than PFB and EPS in vitro. Further purification and structure analyses indicated that IPS mainly consisted of three fractions (IPS-I, IPS-II and IPS-III). FT-IR and NMR data indicated that IPS was mainly composed of (1 â†’ 6)-linked α-d-glucose. There are significant differences of antioxidant activities among IPS-I, IPS-II and IPS-III fractions in vitro, and IPS-III showed stronger antioxidant activity than IPS-I and IPS-II. IPS-III also possesses a potent antioxidant ability inside HepG2 cells, and it could protect HepG2 cells from H2O2-induced cytotoxicity by scavenging overproduced cellular ROS and inhibiting SOD, CAT and GSH depletion to weaken lipid peroxidation. These findings suggested that IPS-III could be a novel antioxidant and that it could afford protection against H2O2-induced cytotoxicity and oxidative stress.

Purification of an iron-binding peptide from scad (Decapterus maruadsi) processing by-products and its effects on iron absorption by Caco-2 cells.

This work was aimed at producing peptides containing iron-binding capabilities from scad (Decapterus maruadsi) processing by-product with alcalase hydrolysis. The chelating peptides were purified by ultrafiltration, immobilized-metal affinity chromatography, gel filtration chromatography, and reversed-phase high-performance liquid chromatography. A novel iron-binding peptide was purified with 1,386.63 Da molecular weight and amino acid sequence of QKGTYDDYVEGL. The peptide binds to iron mainly through carboxyl and hydroxyl oxygen bonds. The iron-binding peptide can significantly promote the absorption of inorganic iron in Caco-2 cells. These results have contributed to development of the peptide from scad processing by-products hydrolyzate in iron supplementations. PRACTICAL APPLICATIONS: Iron deficiency is one of the most common and widespread nutritional disorders in the world. Iron-peptide chelates may be suitable for iron-fortification. Our study shows that a peptide purified from scad processing by-product has iron-chelating activity, and significantly increases iron absorption by Caco-2 cells. Hence, this peptide has potential application as a novel carrier for enhancing iron absorption.

Fructus mori L. polysaccharide-iron chelates formed by self-embedding with iron(iii) as the core exhibit good antioxidant activity.

Mulberry fruit polysaccharide (MFP) was obtained from Morus alba L. by a hot water extraction method, and mulberry polysaccharide fractions named MFP1, MFP2 and MFP3 were isolated by DEAE cellulose-52 column chromatography. Monosaccharide analysis of MFP1, MFP2 and MFP3 showed that the three components had the same monosaccharide compositions with different ratios, and galacturonic acid was the main monosaccharide component. Molecular weight measurements showed that MFP1 and MFP2 are heteropolysaccharides and MFP3 is a homogeneous polysaccharide. In addition, the chelate mechanism of iron(iii) and polysaccharide is proposed in which iron(iii) as a core is enwrapped by the polysaccharide as a ligand by hydroxyl and carboxyl groups, which induces a morphology change from flat sheets to rods and increases the size. Furthermore, the polysaccharides showed strong antioxidant activity to eliminate hydroxyl radicals and inhibit MDA production in healthy mouse liver homogenate. Also, the polysaccharide-iron(iii) chelates exhibited stronger superoxide radical scavenging ability than the polysaccharides. These results suggest that the polysaccharides derived from Morus alba L. are promising candidates for fabricating organic iron supplements with good antioxidant activity.

Chemical analysis, moisture-preserving, and antioxidant activities of polysaccharides from Pholiota nameko by fractional precipitation.

This study explored Pholiota nameko (P. nameko) polysaccharide fractions, PNP-40, PNP-60, and PNP-80, purified by gradient concentrations of ethanol (40%, 60%, and 80% (v/v)). The physicochemical properties, functional group composition, moisture-preserving, and antioxidant ability were determined. The results indicate that the polysaccharide contents of PNP-40, PNP-60, and PNP-80 are 45.12%, 78.04%, and 72.22%, respectively, while the ß-glucan, protein, and uronic acid contents are 20.20%, 12.20%, and 10.15%, respectively; 11.24%, 14.53%, and 26.94%; and 5.99%, 7.73%, and 3.78%. Furthermore, PNP-60 has better moisture absorption, while PNP-80 has better antioxidant ability and H2O2-injury resistance activity. Monosaccharide composition analysis shows that P. nameko belongs to heteropolysaccharides, which consists of galactose, glucose, and mannose with different types and ratios, and the molecular weight are distributed at 4.40-333.49kDa. It was found that different polysaccharide fractions have the potential to be a moisturizer and an antioxidant, and their active ingredients could be used in the development of cosmetic ingredients.

Antioxidant activity of an ethnobotanically important plant Quisqualis indica Linn.

The antioxidant potential of leaf, stem, root and flower extracts of Quisqualis indica Linn. was assessed to verify its ethnopharmacological importance. Both polar and non-polar solvents like n-hexane, chloroform, ethanol and distilled water were used to obtain crude extracts. The chloroform extract of leaves showed the maximum %age yield, i.e. 27.3% while the n-hexane extract of stem showed the minimum yield, i.e. 0.2%. Five activities including DPPH free radical scavenging activity, ABTS+ assay, Total flavonoid components (TFC), Total phenolic components (TPC) and Metal chelating Assay (MC) were employed to evaluate the antioxidant activity of the plant. The ethanol extract of inflorescence of the plant displayed most elevated DPPH potential, i.e. 452.11%. Aqueous extract of root had highest value of TEAC i.e., 7.4515 mmol. The aqueous extract of flower displayed the highest level of phenolic contents with the value of 35 in terms of GAE mg/mL. On the other hand, the chloroform extract had the highest % bound iron value of 128 and the aqueous extract of flower showed a high concentration of Flavonoids having the value 347.65mg/l of Quercetin. It has been inferred that all parts of Quisqualis indica L. possess good antioxidant potential. Differents parts showed different antioxidant potentials hence they can be used as curative agents against human and animal ailments.

An ellagic acid isolated from Clerodendrum viscosum leaves ameliorates iron-overload induced hepatotoxicity in Swiss albino mice through inhibition of oxidative stress and the apoptotic pathway.

Iron is a vital element required for normal cellular physiology in animal systems, but excess iron accumulation in the biological system accelerates oxidative stress, cellular toxicity, tissue injury and organ fibrosis, which ultimately leads to the generation of chronic liver diseases including cancer. A natural antioxidant, ellagic acid (EA) has been previously reported for its pharmacological properties; however, there is no significant evidence available that could illustrate its protective potential against iron-overload induced hepatotoxicity. In the present work, EA was evaluated for its in vitro free radical scavenging and iron chelation potentials. Further, EA was tested in vivo for its protective activity against iron overload-induced hepatotoxicity in Swiss albino mice by evaluating liver iron content, reactive oxygen species (ROS), liver antioxidant enzymes, serum marker levels, liver damage and fibrosis, histopathological study and finally western blotting analysis. EA treatment significantly decreased liver iron and serum ferritin levels. Elevated ROS levels, decreased antioxidant parameters and elevated serum markers were normalized upon treatment with EA. Cellular morphology, iron -overload and liver fibrosis were found to be effectively ameliorated. Finally, the protective effect of EA against iron overload-induced apoptosis was confirmed by western blotting when its treatment upregulated the expressions of caspase-3 and poly(ADP-ribose) polymerase (PARP) proteins. EA revealed hepatoprotective activity against iron overload-induced toxicity through scavenging free radicals, inhibiting excess ROS production, normalizing liver damage parameters and upregulating caspase-3, PARP expression. Collectively, our findings support the possible use of the natural antioxidant EA as a promising candidate against iron-overloaded diseases.

Comparative study on the physicochemical and functional properties of the mucilage in the carpel of Nymphaea odorata using ultrasonic and classical heating extractions.

The cooked carpel of Nymphaea odorata has a large amount of transparent mucilage; however, the basic characteristics of this mucilage have not yet been reported. This study compared the physicochemical and functional properties of this mucilage obtained using conventional hot water extraction (HWM) and ultrasonic-assisted extraction (UAM). Neither HWM nor UAM affected the viability of mouse skin fibroblasts (NIH/3 T3) below 100 µg/mL. UAM had a higher yield production, phenol concentration, and in vitro antioxidant activity, but it had a lower viscosity and water-holding capacity than that of HWM. The Fourier transform infrared spectra revealed that the dialyzed HWM and UAM, named HWMD and UAMD, respectively, appeared to have major spectral differences at 1730 cm-1 and 1605 cm-1, implying that the degree of methylation was different between HWMD and UAMD. Compared to HWMD, UAMD in low-molecular weight polysaccharides increased. Indeed, the basic characteristics of native mucilage in the carpel of N. odorata were greatly changed by various extractions. Nevertheless, sugar analysis indicated that glucuronic acid was the main composition of HWMD and UAMD.

Effect of extraction techniques on properties of polysaccharides from Enteromorpha prolifera and their applicability in iron chelation.

The structural characteristics of polysaccharides directly affect their property, function, and application. Enteromorpha prolifera, a resource-rich green alga, contains special sulfated rhamnose-rich polysaccharides. In this study, the physicochemical properties of polysaccharides extracted from E. prolifera using different techniques were compared, and significant differences in yield, molecular weight, and chemical composition were observed. The acid extraction had the highest extraction yield (24.7%), and the obtained polysaccharides (ACP) had a molecular weight of 41.1kDa and sulfate content of 16.2%. ACP showed a good iron(III) chelating capacity, and after response surface optimization, the iron content of ACP-iron(III) complex reached 20.85%. According to the structure analysis, iron(III) was bound with hydroxyl and carboxyl of ACP. Soluble polysaccharides are the main component of E. prolifera tissue, easy to prepare, and with unique properties. The prepared ACP-iron(III) complex may be a powerful candidate for iron supplements.

Preparation of purified fractions for polysaccharides from Monetaria moneta Linnaeus and comparison their characteristics and antioxidant activities.

The aim of this paper was to prepare purified fractions of polysaccharides from Monetaria moneta Linnaeus and further compare their characteristics and antioxidant activities. Firstly, three novel purified fractions, named MM-P1, MM-P2 and MM-P3, were successfully prepared by a DEAE-Sepharose fast-flow column. Then, their characteristics were compared using chemical testing, FT-IR, GC and HPGPC. The results suggested that MM-P3 had higher molecular weights than MM-P1 and MM-P2. MM-P1 was consisted of glucose, MM-P2 was consisted of glucose and xylose, and MM-P3 was comprised of glucose, xylose and mannose. Differed from MM-P1 and MM-P2, MM-P3 had sulfuric radical and uronic acid groups. Finally, their antioxidant activities were also compared. We found that MM-P3 exhibited better antioxidant bioactivities than MM-P1 and MM-P2. The data demonstrated that three purified fractions derived from different adsorption capacity of DEAE-Sepharose fast-flow column possessed different structural characteristics and antioxidant activity.

Antioxidant activity of different extracts from the aerial part of Moringa peregrina (Forssk.) Fiori, from Jordan.

The antioxidant activities of methanol (M), ethyl acetate (E) and hexane (H) extracts from leaves (L) and seeds (S) of Moringa (Moringa peregrina) were evaluated using different model systems in vitro. Free radical scavenging activities were assessed by measuring the scavenging activities of leaves and seeds different polar extracts separately using ABTS, Hydroxyl (OH) and DPPH radicals. Effect of extracts on ferrous ions chelating ability and total antioxidant capacity were also investigated for each extract. In addition, total phenolics, flavonoids and flavonols content of Moringa leaves and seeds extracts were determined. The leaves methanol (LM) extract showed significantly the highest DPPH radical scavenging activity (IC50value of 5.3±0.2µ/ml), followed by leaves ethylacetate extract (LE) and seeds methanolic extract (SM) with IC50 values of 7.1±0.2 and 7.2±0.4µ/ml, respectively. LE extract showed the highest ABTS radical scavenging activity with IC50value of 49.1±2.7µ/ml, followed by LM extract with IC50value of 61.2±1.2 µ/ml, whereas the highest hydroxyl radical (OH.) inhibition activity was found for LM and SM extracts with IC50 values of 76.9±0.8 and 77.5±1.2µ/ml, respectively. The total antioxidant activity was the highest in LM, LE and SM extracts (294.3, 244.5 and 231.6µ ascorbic acid equivalent for 1mg extract, respectively). LM, LE and SM extracts at concentration of 100µ/ml showed the highest chelating activity against ferrous ions (98.4, 91.1 and 90.7%, respectively). All Moringa leaves and seeds extracts showed pronounced antioxidant activities in a dose dependent manner and the effects depend strongly on the solvent used for extraction. The results showed that extracts of both leaves and seeds of Moringa exhibit antioxidant potential suggesting that M. peregrina is a promising plant.

Phytochemical screening, GC-MS analysis and in vitro antioxidant activity of pollen of Centella asiatica (Linn) urban a traditional medicinal plant.

In the present study the crude extracts of pollen of Centella asiatica (Linn.) Urban were explored for their antioxidant potential using Ferric Reducing Power, Metal Chelating Activity and Trolox Equivalent Antioxidant Capacity assays. In crude extracts of pollen antioxidant components were initially extracted in methanol and further fractionated in solvents of different polarity, such as n-Hexane, Chloroform, Ethyl Acetate and Water exhibited reasonable antioxidant activity. The extract was found to contain large amounts of phenolic and flavonoid contents ranged from 143-1155 mg/l of gallic acid equivalent (GAE) and 911-2488 mg/l of quercetin (QE) respectively. Moreover, Super oxide Anion Radical Scavenging Activity and GS-MS analysis were also carried out.

Isolation and characterization of iron chelators from turmeric (Curcuma longa): selective metal binding by curcuminoids.

Iron overload disorders may be treated by chelation therapy. This study describes a novel method for isolating iron chelators from complex mixtures including plant extracts. We demonstrate the one-step isolation of curcuminoids from turmeric, the medicinal food spice derived from Curcuma longa. The method uses iron-nitrilotriacetic acid (NTA)-agarose, to which curcumin binds rapidly, specifically, and reversibly. Curcumin, demethoxycurcumin, and bisdemethoxycurcumin each bound iron-NTA-agarose with comparable affinities and a stoichiometry near 1. Analyses of binding efficiencies and purity demonstrated that curcuminoids comprise the primary iron binding compounds recovered from a crude turmeric extract. Competition of curcuminoid binding to the iron resin was used to characterize the metal binding site on curcumin and to detect iron binding by added chelators. Curcumin-Iron-NTA-agarose binding was inhibited by other metals with relative potency: (>90% inhibition) Cu2+ ~ Al3+ > Zn2+ ≥ Ca2+ ~ Mg2+ ~ Mn2+ (<20% inhibition). Binding was also inhibited by pharmaceutical iron chelators (desferoxamine or EDTA) or by higher concentrations of weak iron chelators (citrate or silibinin). Investigation of the physiological effects of iron binding by curcumin revealed that curcumin uptake by cultured cells was reduced >80% by addition of iron to the media; uptake was completely restored by desferoxamine. Ranking of metals by relative potencies for blocking curcumin uptake agreed with their relative potencies in blocking curcumin binding to iron-NTA-agarose. We conclude that curcumin can selectively bind toxic metals including iron in a physiological setting, and propose inhibition of curcumin binding to iron-NTA-agarose for iron chelator screening.

Isolation, Characterization and Bioactivities of an Extracellular Polysaccharide Produced from Streptomyces sp. MOE6.

A Streptomyces strain was isolated from soil and the sequence of 1471 nucleotides of its 16S rDNA showed 99% identity to Streptomyces sp. HV10. This newly isolated Streptomyces strain produced an extracellular polysaccharide (EPS) composed mainly of glucose and mannose in a ratio of 1:4.1, as was characterized by Fourier transform infrared spectroscopy (FTIR), HPLC and ¹H-NMR. The antioxidant activities of the partially purified MOE6-EPS were determined by measuring the hydroxyl free radical scavenging activity and the scavenging of 2,2-diphenyl-2-picryl-hydrazyl (DPPH) radicals. In addition, the partially purified MOE6-EPS showed high ferrous ion (Fe2+) chelation activity which is another antioxidant activity. Interestingly, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays that were colorimetric assays for NAD(P)H-dependent cellular oxidoreductases and a proxy of the number of viable cells, showed that the partially purified MOE6-EPS inhibited the proliferation of the human breast cancer cells (MDA-MB-231). The scratch wound assay showed that MOE6-EPS reduced the migration of mouse breast cancer cells (4T1). This study reports the production of EPS from Streptomyces species with promising antioxidant, metal chelating and mammalian cell inhibitory activities.

Phytochemical Profile and Biological Activities of Helianthemum canum l. baumg. from Turkey.

In the current study, antioxidant, antibacterial activities, and the phenolic compositions of extracts from Helianthemum canum L. Baumg. (Apiaceae) aerial parts were investigated for the first time. The H. canum was extracted with 70% methanol (HCMeOH) and water (HCW). Both extracts were determined by total phenolic contents (3 mg/ml), flavonoids (1.5 mg/ml), flavonols (1.5 mg/ml), qualitative-quantitative compositions, iron (II) chelation activities (0.1 - 5 mg/ml), free radical scavenging activities (DPPH• : 0.01 - 0.6 mg/ml and ABTS+• : 0.125 - 0.5 mg/ml) and the effect upon inhibition of ß-carotene/linoleic acid co-oxidation (1 mg/ml). The peroxidation level was also determined using the thiobarbituric acid method (0.01 - 1.5 mg/ml). The results of the activity tests given as IC50 values were estimated from non-linear algorithm and compared with standards. Antibacterial activities of extracts and standards were evaluated against Gram-negative and -positive ten standard strains using disc diffusion and broth microdilution methods. The MIC results (312.5 - 2500 µg/ml) against tested microorganisms varied from 625 to 2500 µg/ml. In HPLC analysis, 3,5-dihydroxybenzoic acid was found as the main substance in both extracts. These results showed that HCMeOH was richer in phenolic compounds (284.13 ± 0.30 mg GAE/g extract) from HCW (244.55 ± 0.35 mg GAE/g extract). In conclusion, H. canum extracts showed in vitro antibacterial and antioxidant activities.

Inhibition of lipoxygenase by sesamol corroborates its potential anti-inflammatory activity.

Reactive oxygen species, the byproducts of oxygenases reaction, when in excess, promote degenerative diseases like cardiovascular, cancer and arthritis. Sesame lignans- sesamin, sesamolin and the phenolic degradation product of sesamolin, sesamol, are empirically known for their health promoting properties like antioxidant, antimutagenic, antiaging and antiinflammatory activities. In the current study, the effect of sesamol on the inflammatory oxygenase - lipoxygenase (LOX) was investigated. Enzyme kinetics and spectroscopic techniques were used to understand the inhibition mechanism. Sesamol was a potent inhibitor of soy LOX-1. It inhibited soy LOX-1 in a dose dependent manner with IC50 value of 51.84µM and Ki of 4.9µM. Binding studies using circular dichroism and corroborated by surface plasmon resonance, revealed that sesamol does not bind or change the conformation of LOX. Further, sesamol prevented the conversion of inactive LOX (Fe2+) to active LOX (Fe3+) by arresting the oxidation state of iron and prolonging the lag phase by virtue of its ability to scavenge hydroperoxides. Understanding the mechanism of action of such molecules will help in their application and promotion as nutraceuticals.