Comparison of Usefulness of Four Chelating Agents (EDTA, NTA, ODA and IDA) for the Chromatographic Separation of Micro and Macro Amounts of Rare Earth Elements.

Literature on the use of four chelating agents namely: ethylenediaminetetraacetic acid, nitrilotriacetic acid, diglycolic acid and iminodiacetic acid for the chromatographic separation of micro and macro amounts of rare earth elements was critically reviewed and supplemented with some new unpublished data from our Laboratory. Advantages and disadvantages of ion exchange chromatography both in cation and anion mode as well as ion interaction chromatography techniques, which were used for rare earth elements separation, are discussed. The usefulness of some of the chromatographic systems for micro-macro separations was discussed and demonstrated. The importance of resilience of the separation method to column overloading in some analytical and larger scale separations was emphasized. The methods described in this article might suit well for recovering of individual lanthanides and yttrium from e-waste and other industrial wastes which were fast accumulating in recent years.

Assessment of the Antitumor Activity of Green Biosynthesized Zinc Nanoparticles as Therapeutic Agent Against Renal Cancer in Rats.

Zinc nanoparticles (Zn-NPs) have garnered a great deal of attention as potential cancer therapy. The use of microorganisms in the synthesis of nanoparticles emerges as an eco-friendly and exciting approach. This study was designed to assess biosynthesized Zn-NPs as therapeutic agent against kidney cancer induced by ferric-nitrilotriacetate (Fe-NTA) in rats.Zn-NPs were synthesized from edible mushroom then characterized by transmission electron microscopy analysis, dynamic light scattering, and Fourier transform infrared spectroscopy. Rats were divided into 4 different groups: group I (control), group II (Fe-NTA group), group III (Zn-NPs group), and group IV (Fe-NTA + Zn-NPs group). Animals were sacrificed then kidney and liver function tests, MDA level, glutathione, glutathione peroxidase, and superoxide dismutase activities were measured by using colorimetric methods. Caspase-3 level and carcinoembryonic antigen concentration were measured by using ELISA. Finally, DNA fragmentation was visualized by using agarose gel electrophoresis.Treatment with Zn-NPs significantly suppressed renal oxidative stress by restoring glutathione level, glutathione peroxidase, and superoxide dismutase activities and ameliorated oxidative damage parameters of lipid peroxidation as well as renal toxicity markers. Molecular and tumor markers showed significant improvement with respect to induction group, and this was well appreciated with the histopathological alteration findings in the treated groups.Microbial synthesized Zn-NPs possess antitumor-promoting activity against Fe-NTA-induced toxicity and carcinogenesis, which should be evaluated in a clinical study.

Comparison of synthetic and organic biodegradable chelants in augmenting cadmium phytoextraction in Solanum nigrum.

This study focused to enhance the cadmium (Cd) phytoextraction efficiency in Solanum nigrum by applying four biodegradable chelants (10 mM)-ethylene glycol tetraacetic acid (EGTA), ethylenediamine disuccinate (EDDS), nitrilotriacetic acid (NTA), and citric acid (CA), when grown in Cd-spiked soil (12 and 48 mg kg-1). Plant height, dry biomass, photosynthetic traits, and metal accumulation varied significantly with Cd and chelant treatments. Cadmium-toxicity resulted in reduction of plant growth and photosynthetic physiology, whereas chelant supplementation alleviated the toxic effect of Cd and increased its accumulation. Tolerance index value increased with addition of chelants in the order: EGTA (1.57-1.63) >EDDS (1.39-1.58) >NTA (1.14-1.50) >CA (1-1.22) compared with Cd (0.46-1.08). Transfer coefficient of root increased with supplementation of EGTA (3.40-3.85), EDDS (3.10-3.40), NTA (2.60-2.90), and CA (1.85-2.29), over Cd-alone (1.61-1.63). Similarly, translocation factor was also increased upon addition of EGTA (0.52-0.73), EDDS (0.35-0.81), NTA (0.38-0.75), and CA (0.53-0.54), compared with Cd-alone (0.36-0.59). Maximum Cd removal (67.67% at Cd12 and 36.05% at Cd48) was observed with supplementation of EGTA. The study concludes that the supplementation of EGTA and EDDS with S. nigrum can be employed as an efficient and environmentally safe technique for reclamation of Cd-contaminated soils.

Apart from the selection of a good hyperaccumulator, the choice of chelant (biodegradable/non-biodegradable) is an important aspect for the successful phytoextraction of metals from contaminated soil. We reported for the first time the potential of ethylene glycol tetraacetic acid (EGTA; a biodegradable chelant) in enhancing Cd phytoextraction by Solanum nigrum. Comparative appraisal of metal extraction efficiency of biodegradable chelants at low (12 mg kg⁻¹) and high (48 mg kg⁻¹) Cd dose depicted that EGTA performed better than EDDS, NTA, and CA (other biodegradable chelants). EGTA supplementation did not induce toxicity in plants; rather it improved metal accumulation, morphology, and photosynthetic physiology.

Pueraria montana (Kudzu vine) Ameliorate the Inflammation and Oxidative Stress against Fe-NTA Induced Renal Cancer.

Renal tissue plays a crucial function in maintaining homeostasis, making it vulnerable to xenobiotic toxicity. Pueraria montana has more beneficial potential against the various diseases and has long history used as a traditional Chinese medicine. But its effect against the renal cancer not scrutinize. The goal of this study is to see if Pueraria montana can protect rats from developing kidney tumors caused by diethylnitrosamine (DEN) and ferric nitrite (Fe-NTA). Wistar rats was selected for the current study and DEN (use as an inducer) and Fe-NTA (promoter) for induction the renal cancer. For 22 weeks, the rats were given orally Pueraria montana (12.5, 25, and 50 mg/kg) treatment. At regular intervals, the body weight and food intake were calculated. The rats were macroscopically evaluated for identification of cancer in the renal tissue. The renal tumor makers, renal parameters, antioxidant enzymes, phase I and II enzymes, inflammatory cytokines and mediators were estimated at end of the experimental study. Pueraria montana treated rats displayed the suppression of renal tumors, incidence of the tumors along with suppression of tumor percentage. Pueraria montana treated rats significantly (p < 0.001) increased body weight and suppressed the renal weight and food intake. It also reduced the level of renal tumor marker ornithine decarboxylase (ODC) and [3H] thymidine incorporation along with suppression of renal parameter such as uric acid, blood urea nitrogen (BUN), urea and creatinine. Pueraria montana treatment significantly (p < 0.001) altered the level of phase enzymes and antioxidant. Pueraria montana treatment significantly (p < 0.001) repressed the level of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and improved the level of interleukin-10 (IL-10). Pueraria montana treatment suppressed the level of prostaglandin (PGE2), cyclooxygenase-2 (COX-2), nuclear kappa B factor (NF-κB) and transforming growth factor beta 1 (TGF-ß1). Pueraria montana suppressed the inflammatory necrosis, size the bowman capsules in the renal histopathology. Pueraria montana exhibited the chemoprotective effect via dual mechanism such as suppression of inflammatory reaction and oxidative stress.

Biodegradable chelant-metal complexes enhance cadmium phytoextraction efficiency of Solanum americanum.

Toxic contaminants (metals and metal-containing compounds) are accumulating in the environment at an astonishing rate and jeopardize human health. Remarkable industrial revolution and the spectacular economic growth are the prime causes for the release of such toxic contaminants in the environment. Cadmium (Cd) is ranked the 7th most toxic compound by the Agency for Toxic Substances and Disease Registry (USA), owing to its high carcinogenicity and non-biodegradability even at miniscule concentration. The present study assessed the efficiency of four biodegradable chelants [nitrilotriacetic acid (NTA), ethylenediamine disuccinate (EDDS), ethylene glycol tetraacetic acid (EGTA), and citric acid (CA)] and their dose (5 mM and 10 mM) in enhancing metal accumulation in Solanum americanum Mill. (grown under 24 mg Cd kg-1 soil) through morpho-physiological and metal extraction parameters. Significant variations were observed for most of the studied parameters in response to chelants and their doses. However, ratio of root and shoot length, and plant height stress tolerance index differed non-significantly. The potential of chelants to enhance Cd removal efficiency was in the order - EGTA (7.44%) > EDDS (6.05%) > NTA (4.12%) > CA (2.75%). EGTA and EDDS exhibited dose-dependent behavior for Cd extraction with 10 mM dose being more efficient than 5 mM dose. Structural equation model (SEM) depicted strong positive interaction of metal extraction parameters with chelants (Z-value = 11.61, p = 0.001). This study provides insights into the importance of selecting appropriate dose of biodegradable chelants for Cd extraction, as high chelant concentration might also result in phytotoxicity. In the future, phytoextraction potential of these chelants needs to be examined through field studies under natural environmental conditions.

Effect of nitrilotriacetic acid and tea saponin on the phytoremediation of Ni by Sudan grass (Sorghum sudanense (Piper) Stapf.) in Ni-pyrene contaminated soil.

Phytoremediation is commonly used in the remediation of soils co-contaminated by heavy metals and polycyclic aromatic hydrocarbons (PAHs) because of its economy and effectiveness. Sudan grass (Sorghum sudanense (Piper) Stapf.) has well-developed roots and strong tolerance to heavy metals, so it has been widely concerned. In this study, nitrilotriacetic acid (NTA) and tea saponin (TS) were used as enhancers and combined with Sudan grass for improving the remediation efficiency of Ni-pyrene co-contaminated soil. The results of the pot experiment in soils showed that enhancers promoted the enrichment of Ni in plants. With the function of enhancers, more inorganic and water-soluble Ni were converted into low-toxic phosphate-bonded and residual Ni, so as to reinforce the tolerance of Sudan grass to Ni. In the pot experiment based on vermiculite, it was found that enhancers increased the accumulation of Ni in cell wall by 49.71-102.73%. Enhancers also had the positive effect on the relative abundance of Proteobacteria, Patescibacteria and Bacteroidetes that could tolerate heavy metals at phylum level. Simultaneously, the study found that pyrene reduced the exchangeable Ni in soils. More Ni entered the organelles and transfer to more high-toxic forms in Sudan grass when pynere coexisted. The study manifested that enhancers improved the phytoremediation effect of Ni significantly, yet the co-existence of pyrene weakened the process. Our results provided meaningful references for remediating actual co-contaminated soil of heavy metals and PAHs.

The therapeutic potential of curcumin in alleviating N-diethylnitrosamine and iron nitrilotriacetate induced renal cell tumours in mice via inhibition of oxidative stress: Implications for cancer chemoprevention.

This study was designed to reveal the protective effects of dietary supplementation of curcumin against renal cell tumours and oxidative stress induced by renal carcinogen iron nitrilotriacetate (Fe-NTA) in ddY male mice. The results showed that mice treated with a renal carcinogen, Fe-NTA, a 35% renal cell tumour incidence was noticed, whereas renal cell tumour occurrence was elevated to 80% in Fe-NTA promoted and N-diethylnitrosamine (DEN)-initiated mice as compared with saline- treated mice. No incidence of tumours has been observed in DEN-initiated non-promoted mice. Diet complemented with 0.5% and 1.0% curcumin fed prior to, during and after treatment with Fe-NTA in DEN-initiated animals, tumour incidence was reduced dose-dependently to about 45% and 30% respectively. Immunohistochemical studies also revealed the increased formation of 4-hydroxy-2-nonenal (HNE)-modified protein adducts and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in kidney tissue of mice treated with an intraperitoneal injection of Fe-NTA (6.0 mg Fe/kg body weight.). Furthermore, Fe-NTA treatment of mice also resulted in significant elevation of malondialdehyde (MDA), serum urea, and creatinine and decreases renal glutathione. However, the changes in most of these parameters were attenuated dose-dependently by prophylactic treatment of animals with 0.5% and 1% curcumin diet, this may be due to its antioxidative impact of curcumin. These results suggest that intake of curcumin is beneficial for the prevention of renal cell tumours and oxidative stress damage mediated by renal carcinogen, Fe-NTA.

Fluorescent Single-Walled Carbon Nanotubes for Protein Detection.

Nanosensors have a central role in recent approaches to molecular recognition in applications like imaging, drug delivery systems, and phototherapy. Fluorescent nanoparticles are particularly attractive for such tasks owing to their emission signal that can serve as optical reporter for location or environmental properties. Single-walled carbon nanotubes (SWCNTs) fluoresce in the near-infrared part of the spectrum, where biological samples are relatively transparent, and they do not photobleach or blink. These unique optical properties and their biocompatibility make SWCNTs attractive for a variety of biomedical applications. Here, we review recent advancements in protein recognition using SWCNTs functionalized with either natural recognition moieties or synthetic heteropolymers. We emphasize the benefits of the versatile applicability of the SWCNT sensors in different systems ranging from single-molecule level to in-vivo sensing in whole animal models. Finally, we discuss challenges, opportunities, and future perspectives.

Sorption technique as a tool for reduction of genotoxicity.

In the present study, the Allium cepa root chromosomal aberration assay was used to determine the genotoxic effects of copper and cadmium ions solutions before and after sorption processes. The sorption process was carried out using unmodified Dendrocalamus strictus charcoal powder, nitrilotriacetic acid (NTA)-modified D. strictus charcoal powder, and Saccharomyces cerevisiae. The frequency of total chromosomal aberrations was observed to be 24.30-45.13% for copper and 13.16-45.14% for cadmium at different concentrations (1-500 mg/l) before the sorption process. Both metal ions solutions resulted in significant reduction of chromosomal aberrations after all the modes of the sorption processes. However, the order of reduction of percentage chromosomal aberrations for copper and cadmium solutions was found to be 45.29-70.04% and 47.80-84.57%, respectively (NTA-modified D. strictus charcoal powder); >44.53-54.32% and 37.10-79.40%, respectively (unmodified D. strictus charcoal powder); >15.59-48.51% and 13.63-21.50%, respectively (S. cerevisiae).

Anti-carcinogenic effect of hesperidin against renal cell carcinoma by targeting COX-2/PGE2 pathway in Wistar rats.

The present study was designed to evaluate the protective effects of hesperidin, a flavonoid on DEN initiated and Fe-NTA promoted renal carcinogenesis in Wistar rats. Renal cancer was initiated by a single i.p. injection of DEN (200 mg/kg b.wt.) and promoted with Fe-NTA (9 mg Fe/kg b.wt. i.p.) twice a week for 16 weeks. Rats were simultaneously administered with hesperidin (100 and 200 mg/kg b.wt.) for 16 consecutive weeks. The chemopreventive effect of hesperidin was assessed in terms of antioxidant activities, renal function, PGE2 level, and the expressions of COX-2 and VEGF. Hesperidin decreased the DEN and Fe-NTA induced lipid peroxidation, improved the renal function (by decreasing the levels of BUN, creatinine, and KIM-1) and restored the renal antioxidant armory (GSH, GPx, GR, SOD, and catalase). Hesperidin was also found to decrease the level of PGE2 and downregulate the expressions of COX-2 and VEGF. Histological findings further revealed the protective effects of hesperidin against DEN and Fe-NTA induced kidney damage. The result of our present findings suggest that hesperidin may be a promising modulator in preventing renal cancer possibly by virtue of its ability to alleviate oxidative stress and inhibit COX-2/PGE2 pathway.

The Natural Product Curcumin as a Potential Coadjuvant in Alzheimer's Treatment.

Alzheimer's disease (AD) is a neurodegenerative disease characterized by a progressive cognitive impairment of patients, affecting around 12% of people older than 65 years old. WHO estimated that over 48.6 million all over the world suffer this disease. On the basis of cumulative results on our research, we have postulated the neuroimmunomodulation hypothesis that appears to provide a reasonable explanation of both the preclinical and clinical observations. In this context, the long-term activation of the innate immune system triggers an anomalous cascade of molecular signals, finally leading to tau oligomerization in the pathway to neuronal degeneration. In the present scenario of the failure of many anti-AD drugs, nutraceutical compounds provide an avenue for AD prevention and possibly as coadjuvants in the treatment of this disease. Recent discoveries point to the relevance of curcumin, a natural anti-inflammatory agent, in controlling oxidative stress and improving cholinergic function in the brain, even though the mechanisms underlying these actions are unknown. We investigated the effects of curcumin in cultures of neuronal cells. For this study, we exposed cells to prooxidant conditions, both in the presence and absence of curcumin. Our data reveal that curcumin exert a strong neuroprotective effect in N2a cells, thus preventing toxicity by oxidative agents H2O2 and Fe+3. This is supported by results that indicate that curcumin control the neurodegenerative effects of both oxidative agents, relieving cells from the loss of neuritogenic processes induced by prooxidants. In addition, curcumin was able to slow down the tau aggregation curve and disassemble tau pathological oligomeric structures. Data suggest that curcumin could be a potential compound for prevention of cognitive disorders associated with AD.

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.

New insights into the antioxidant activity and cytotoxicity of arzanol and effect of methylation on its biological properties.

The heterodimeric phloroglucinyl pyrone arzanol (Arz) has raised considerable interest because of its antiviral, anti-inflammatory, and antioxidant activity. We have investigated the effect of methylation of the pyrone moiety on the antioxidant activity and cytotoxicity of Arz. This manoeuvre, that left the polyphenolic moiety unscathed, was nevertheless detrimental for antioxidant activity in both the cholesterol thermal degradation- and the Cu2+-induced liposome oxidation assays, providing evidence of structure-activity relationships that go beyond the preservation of the polyphenolic pharmacophore. The antioxidant activity of Arz was retained also in the Fe-NTA model of in vivo oxidative stress, with protective effect on the oxidative degradation of plasmatic lipids, unsaturated fatty acids and cholesterol. Both Arz and methylarzanol (Me-Arz) were devoid of toxic effect on colonic differentiated Caco-2 cells up to 100µM, but significantly reduced cancer Caco-2 cell viability at lower dosages. Arz could also selectively reduce viability of other cancer cell lines, [murine melanoma cells (B16F10 cells), human cervical carcinoma cells (HeLa cells)], suggesting that it can act as a selective modulator of cell processes typical of cancer cells. Taken together, our results qualify Arz as a lead structure for further in vivo investigation of its pharmacological potential.

Organo-protective and antioxidant properties of leaf extracts of Syzygium guineense var macrocarpum against ferric nitriloacetate-induced stress of Wistar rats.

Background The present study focused on the antioxidant, phenolic profile and free radical scavenging-mediated protective effect of leaves extracts of Syzygium guineense var. macrocarpum against ferric nitriloacetate-induced stress in the liver, heart, kidney and brain tissues of Wistar rats homogenates. Methods Spectrophotometric standardized methods were used to determine the free radical scavenging potential, antioxidant and protective properties of plant extracts on rat homogenates. Results All the extracts showed a concentration-dependent free radical quenching potential, and the ability to protect all the tested organs by inhibiting the lipid peroxidation and potentiating or restoring the activity of enzymatic and non enzymatic markers. The polyphenolic profile revealed the presence of at least one simple phenolic acid (gallic, caffeic, para-coumaric acid) although the majority (6 out of 14) of the compounds used as standard are present in the aqueous and aqueous-ethanol extracts. Conclusions Ethanolic extract of leaves of S. guineense var macrocarpum (SGETOH) exhibited the highest phenol content and appeared as the best extract taking into consideration the antioxidant and organo-protective activities tested.

Chemomodulatory effect Melastoma Malabathricum Linn against chemically induced renal carcinogenesis rats via attenuation of inflammation, oxidative stress, and early markers of tumor expansion.

Melastoma malabathricum Linn (MM) has high valued for its commercial significance. Indian market (northeast) has great demand for the plants, which extended, its use as a traditional home remedy due to its anti-inflammatory effects. In this study, we scrutinize the therapeutic and protective effect of MM against diethylnitrosamine (DEN) and ferric nitrilotriacetate (Fe-NTA)-induced renal carcinogenesis, renal hyperproliferation, and oxidative stress in rats. Liquid chromatography mass spectroscopy (LC-MS) was used for identification of phytoconstituents. Administration of DEN confirmed the initiation the renal carcinogenesis via enhancing the expansion of tumor incidence. Intraperitoneally, administration of Fe-NTA boost the antioxidant enzymes (phase I), viz., superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and phase II, viz., quinone reductase (QR) and glutathione-S-transferase (GST). It also increased the content of renal lipid peroxidation (LPO), hydrogen peroxidase (H2O2) with decrease content in glutathione content (GSH). It also increased the renal biochemical and non-biochemical parameter. It also confirmed the augment the level of thymidine [3H] incorporation into renal DNA, ornithine decarboxylase (ODC) activity and increased the generation of proinflammatory (TNF-α, IL-6 and IL-ß) and inflammatory mediator (PGE2). We also analyzed the macroscopic and histologic of renal tissue. In addition, the effect of phytoconstituent of MM extract was evaluated in silico and free radical scavenging activity against the DPPH and ABTS free radicals. LC-MS confirmed the presence of quercetin >gallic acid in MM extract. Renal carcinogenesis rats treated with MM (100, 250, and 500 mg/kg) confirmed the significantly (P < 0.001) protective effect via reduction the antioxidant (phase I and phase II) enzymes, biochemical parameter and restore the proinflammatory and inflammatory mediator at dose dependent manner. MM altered the ODC and thymidine activity in renal DNA. The chemoprotective effect of MM was confirmed via decreased the renal tumor incidence, which was confirmed by the macroscopic and histopathological observation. Consequently, our result suggests that MM is a potent chemoprotective agent and suppresses DEN+ Fe-NTA-induced renal carcinogenesis, inflammatory reaction, and oxidative stress injury in Wister rats.

In vitro organo-protective effect of bark extracts from Syzygium guineense var macrocarpum against ferric-nitrilotriacetate-induced stress in wistar rats homogenates.

BACKGROUND: Overconsumption of oxygen in mammalian cells often lead to the production of reactive oxygen species (ROS) resulting from different mechanisms. Escape of scavenging enzymes/components or nutritional failure are the most important origins. Plant-derived molecules may protect biological molecules either by quenching free radicals, delaying or preventing the ROS formation or by restoring antioxidant enzymes activities. The present study assessed the antioxidant, phenolic profile and protective effect of barks extracts of Syzyguim guineense var macrocarpum against ferric nitriloacetate-induced stress in the liver, heart kidney and brain tissues of wistar rat homogenates. METHODS: Three extracts (aqueous, ethanol and aqueous-ethanol) from the barks of S. guineense var macrocarpum were used in this study. The spectrophotometric standardized methods were used to determine the free radical scavenging and antioxidant potential of the extracts. The protective properties of these plant extracts were also investigated as well as the quantification of secondary metabolites content (total phenolic, flavonoids and flavonols content). The HPLC method helped for characterizing phenolic compounds present in these extracts. RESULTS AND DISCUSSION: All the extracts exhibited a free radical scavenging potential in a concentration dependent manner which varied from 15.18 ± 0.80 to 97.15 ± 0.71 % depending to the type of extract and the method used. The ethanol extract had the higher phenolic content (432.85 mg QE/g extract), including total flavonoids (961.66 mg QE/g extract) and flavonols content (25.12 mg QE/g extract) and higher total antioxidant capacity. Among the phenolic compounds present in the extracts, the HLPC profile revealed the presence of syringic acid and apigenin in all the extracts. The extracts demonstrated their protective effect mostly in liver and brain homogenates by delaying or preventing lipid peroxidation, restoring enzymatic activities and enhancing glutathione levels. CONCLUSION: The overall results demonstrated that the extracts exhibited significant antioxidant and protective effects in liver and brain liver homogenates.

Clinical and methodological factors affecting non-transferrin-bound iron values using a novel fluorescent bead assay.

Nontransferrin-bound iron (NTBI) is a heterogeneously speciated plasma iron, typically detectable when transferrin saturation (TfSat) exceeds 75%. Here, we examine factors affecting NTBI levels by a recently discovered direct chelator-based (CP851) fluorescent bead-linked flow-cytometric assay (bead-NTBI), compared with the established indirect nitrilotriacetate (NTA) assay in 122 iron-overloaded patients, including 64 on recent iron chelation therapy and 13 healthy volunteers. Both methods correlated (r = 0.57, P < 0.0001) but with low agreement, attributable to 2 major factors: (1) the NTA method, unlike the bead method, is highly dependent on TfSat, with NTBI under-estimation at low TfSat and over-estimation once Tf is saturated, (2) the bead method detects <3-fold higher values than the NTA assay in patients on recent deferiprone-containing chelation due to greater detection of chelate complexes but lower values for patients on deferasirox. The optimal timing of sample collection relative to chelation dosing requires further study. Patients with splenectomy, high-storage iron, and increased erythropoiesis had greater discrepancy between assays, consistent with differential access by both methods to the NTBI pools associated with these clinical variables. The bead-NTBI assay has advantages over the NTA assay, being less dependent on TfSat, hence of less tendency for false-negative or false-positive values at low and high TfSat, respectively.

Amelioration of ferric nitrilotriacetate-induced hepatotoxicity in Wistar rats by diallylsulfide.

Garlic contains diallylsulfide (DAS) and other structurally related compounds that are widely believed to be active agents in preventing cancer. This study shows the effect of DAS (a phenolic antioxidant used in foods, cosmetics, and pharmaceutical products) on ferric nitrilotriacetate (Fe-NTA)-induced hepatotoxicity in rats. Male albino rats of Wistar strain weighing 125-150 g were given a single dose of Fe-NTA (9 mg kg(-1) body weight, intraperitoneally) after 1 week of treatment with 100 and 200 mg kg(-1) DAS in corn oil respectively administered through the gavage. Fe-NTA administration led to 2.5-fold increase in the values of both alanine transaminase and aspartate aminotransferase, respectively, and 3.2-fold increase in the activity of lactate dehydrogenase, microsomal lipid peroxidation to approximately 2.0-fold compared to saline-treated control. The activities of glutathione (GSH) and other antioxidant enzymes decreased to a range of 2.2-2.5-fold. These changes were reversed significantly (p < 0.001) in animals receiving a pretreatment of DAS. DAS protected against hepatic lipid peroxidation, hydrogen peroxide generation, preserved GSH levels, and GSH metabolizing enzymes to 60-80% as compared to Fe-NTA alone-treated group. Present data suggest that DAS can ameliorate the toxic effects of Fe-NTA and suppress oxidant-induced tissue injury and hepatotoxicity in rats.

[Antioxidant Activity of Salacia Plant (Salacia reticulata)].

Antioxidant activities of aqueous extracts prepared from powdered leaves and stems of Salacia reticulata, a Salacia plant that grows in Sri Lanka, were investigated. Lipid peroxide levels and some hepatic injury markers in plasma, liver and/or kidney of mice treated with ferric nitrilotriacetate (Fe-NTA) were increased as compared to those of control mice. Oral preadministration of extracts of Salacia leaves and stems at doses of 100, 200 and 400 mg/kg body weight prevented the elevations of lipid peroxides and injury markers in a dose-dependent manner. Decrease of antioxidant activity in plasma of mice treated with Fe-NTA was also prevented by administration of these extracts. In in vitro study, well-known polyphenol components exhibited antioxidant activities, but other effective components were also present in these extracts. The results of this investigation indicate that the extracts of leaves and stems of S. reticulata could be beneficial as health foods for the prevention of oxidative stress-related disorders.

Metabolism of rutin and poncirin by human intestinal microbiota and cloning of their metabolizing α-L-rhamnosidase from Bifidobacterium dentium.

To understand the metabolism of flavonoid rhamnoglycosides by human intestinal microbiota, we measured the metabolic activity of rutin and poncirin (distributed in many functional foods and herbal medicine) by 100 human stool specimens. The average α-Lrhamnosidase activities on the p-nitrophenyl-α-L-rhamnopyranoside, rutin, and poncirin subtrates were 0.10 ± 0.07, 0.25 ± 0.08, and 0.15 ± 0.09 pmol/min/mg, respectively. To investigate the enzymatic properties, α-L-rhamnosidase-producing bacteria were isolated from the specimens, and the α-L-rhamnosidase gene was cloned from a selected organism, Bifidobacterium dentium, and expressed in E. coli. The cloned α-L-rhamnosidase gene contained a 2,673 bp sequcence encoding 890 amino acid residues. The cloned gene was expressed using the pET 26b(+) vector in E. coli BL21, and the expressed enzyme was purified using Ni(2+)-NTA and Q-HP column chromatography. The specific activity of the purified α-L-rhamnosidase was 23.3 µmol/min/mg. Of the tested natural product constituents, the cloned α-L-rhamnosidase hydrolyzed rutin most potently, followed by poncirin, naringin, and ginsenoside Re. However, it was unable to hydrolyze quercitrin. This is the first report describing the cloning, expression, and characterization of α-L-rhamnosidase, a flavonoid rhamnoglycosidemetabolizing enzyme, from bifidobacteria. Based on these findings, the α-L-rhamnosidase of intestinal bacteria such as B. dentium seem to be more effective in hydrolyzing (1-->6) bonds than (1-->2) bonds of rhamnoglycosides, and may play an important role in the metabolism and pharmacological effect of rhamnoglycosides.