Antioxidant Β-carotene Research Articles

Some biological activities of Epaltes divaricata L. - an in vitro study.

BackgroundNovel chemical molecules recovered from endangered medicinal plants have wide applications and have the potential to cure different diseases caused by microorganisms. The aim of this study was to investigate In vitro antimicrobial, α-glucosidase inhibition and antioxidant activity of different solvent extracts of Epaltes divaricata L.MethodsAntimicrobial activity of hexane, ethyl acetate and methanol extract of Epaltes divaricata was determined against bacteria and fungi using disc diffusion and microdilution method respectively. α-glucosidase inhibition, Total phenolic content (TPC), Reducing power activity, DPPH radical scavenging assay, hydroxyl radical scavenging activity, nitric oxide scavenging activity, superoxide scavenging activity and lipid peroxidation assay of plant extracts were performed according to standard protocol. Compound detection from the potential solvent extract was done through GC-MS analysis.ResultsEpaltes divaricata ethyl acetate extracts (EDEa) (1.25 mg/disc) showed significant inhibition for E. lentum (23 mm), E. aerogenes (18 mm), P. fluorescence (15 mm) and A. baumanii (15 mm). Minimum inhibitory concentration (MIC) of EDEa was found to be 31.25 μg/ml, 62.5 μg/ml and 62.5 μg/ml against A. flavus, A. niger and T. rubrum respectively. EDEa showed more α-glucosidase inhibition and antioxidant activity compared to hexane and methanol. EDEa showed 50% α-glucosidase inhibition at the concentration of 525.20 ± 2.37 μg/ml. The TPC of EDEa was 412.0 ± 2.21 mg of catechol equivalents/g extract. EDEa showed great scavenging activity on 2,2-diphenyl-picrylhydrazyl (DPPH) (IC50 560 ± 2.02 μg/ml), hydroxyl (IC50 314.75 ± 2.56 μg/ml), nitric oxide (IC50 648.20 ± 2.09 μg/ml) and superoxide (IC50 361.14 ± 1.45 μg/ml) radicals, as well as high reducing power. EDEa also showed a more suppressive effect on lipid peroxidation. Using Antioxidant β-carotene linoleate method, the scavenging values of EDEa was significantly lower than BHT. GC-MS analysis of EDEa showed maximum amount of 2-butenamide, N-(4-fluorophenyl)-3-methyl trans-cinnamyl tiglate silane and trichlorocyclohexyl silane (36.86%).ConclusionThe results obtained in this study clearly indicate that EDEa can be used as a natural antimicrobial, α-glucosidase inhibition and antioxidant agent.

Advanced lipid systems containing β-carotene: stability under UV-vis radiation and application on porcine skin in vitro.

Phospholipid-based nanostructures, bicelles and bicosomes, are proposed as carriers of the antioxidant β-carotene. The stability of these nanostructures and their carotenoid cargo was evaluated in an oxidation environment induced by ultraviolet A, visible and infrared A radiation (UVA-VIS-IRA). Additionally, the effect of these nanoaggregates on non-irradiated and irradiated skin microstructure was studied. The characterization of the lipid systems was performed using dynamic light scattering (DLS) and cryo-transmission electron microscopy (Cryo-TEM) and lipid peroxidation of the systems was determined by thiobarbituric acid (TBARS) assay. Moreover, the stability of β-carotene in these lipid systems under this radiation was investigated using Raman spectroscopy. The results showed that the particle size of the bicelles did not change due to radiation. However, the size of the bicosomes increased slightly after irradiation. The TBARS assay showed the absence of peroxides in the bicelles and bicosomes, indicating the preservation of the lipid molecules under the radiation used. Raman experiments showed that bicosomes protected β-carotene from degradation induced by radiation better than liposomes or dissolution in chloroform. With respect to the skin microstructure, no changes after irradiation were observed via freeze substitution transmission electron microscopy (FSTEM). This technique also showed the presence of vesicular structures in the stratum corneum (SC) after treatment with bicosomes.

Bicelles and bicosomes as free radical scavengers in the skin

In the present work, β-carotene antioxidant was incorporated in two different lipid nanoaggregates, bicelles and bicosomes, and its effectiveness against free radical formation in porcine skin in vitro was determined using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) spin trap and Electron Paramagnetic Resonance spectroscopy (EPR). Bicelles are discoidal nanostructures formed by self-assembly of phospholipids dispersed in aqueous solution. Bicosomes emerge as a strategy to stabilize and protect bicelles encapsulating these nanostructures in liposomes. Results from Dynamic Light Scattering (DLS) and cryo Transmission Electron Microscopy (cryo-TEM) demonstrated a slight modification in the size of both systems when β-carotene was incorporated. EPR revealed that after skin irradiation both systems presented free radical scavenging activity. This activity was statistically significant for bicosomes containing β-carotene. Differences regarding this scavenging activity between bicelles and bicosomes would probably be due to the different interaction of both systems with the skin. In this study, six different radicals were identified in skin spectra: two originated from oxygen centred radicals (primary/secondary and tertiary alkoxyl radicals) and another from carbon-centred radicals. Additionally, the presence of 5,5-dimethyl-2-oxo-pyrroline-1-hydroxyl (DMPO-OH), 5,5-dimethyl-2-oxo-pyrroline-1-hydrogen (DMPO-H) adducts and aminoxyl radicals (RR′NO˙) were detected. Considering these results, bicelles and bicosomes could be useful lipid systems for future dermopharmaceutical applications.

Serum phytanic and pristanic acid levels and prostate cancer risk in Finnish smokers.

Phytanic acid is a saturated branched-chain fatty acid found predominantly in red meat and dairy products, and may contribute to the elevated risks of prostate cancer associated with higher consumption of these foods. Pristanic acid is formed during peroxisomal oxidation of phytanic acid, and is the direct substrate of α-Methyl-CoA-Racemase (AMACR)—an enzyme that is consistently overexpressed in prostate tumors relative to benign tissue. We measured phytanic and pristanic acids as percentages of total fatty acids by gas chromatography-mass spectrometry in prediagnostic blood samples from 300 prostate cancer cases and 300 matched controls, all of whom were participants in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study supplementation trial and follow-up cohort. In addition to providing a fasting blood sample at baseline, all men completed extensive diet, lifestyle, and medical history questionnaires. Among controls, the strongest dietary correlates of serum phytanic and pristanic acids were saturated fat, dairy fat, and butter (r = 0.50 and 0.40, 0.46 and 0.38, and 0.40 and 0.37, respectively; all P-values <0.001). There was no association between serum phytanic acid and risk of total or aggressive prostate cancer in multivariate logistic regression models (for increasing quartiles, odds ratios (OR) and 95% confidence intervals (CI) for aggressive cancer were 1.0 (referent), 1.62 (0.97–2.68), 1.12 (0.66–1.90), and 1.14 (0.67–1.94), Ptrend = 0.87). Pristanic acid was strongly correlated with phytanic acid levels (r = 0.73, P < 0.0001), and was similarly unrelated to prostate cancer risk. Significant interactions between phytanic and pristanic acids and baseline circulating β-carotene concentrations were noted in relation to total and aggressive disease among participants who did not receive β-carotene supplements as part of the original ATBC intervention trial. In summary, we observed no overall association between serum phytanic and pristanic acid levels and prostate cancer risk. Findings indicating that the direction and magnitude of these associations depended upon serum levels of the antioxidant β-carotene among men not taking β-carotene supplements should be interpreted cautiously, as they are likely due to chance.

Antibacterial, antioxidant and hypoglycaemic effects of Thymus capitatus (L.) Hoffmanns. et Link leaves' fractions

The aim of this study was to examine the bioactivity of the methanol fraction (MF) and n-hexane fraction (HF) of Thymus capitatus leaves in relation to their constituents analysed by gas chromatography and gas chromatography-mass spectrometry. The effects of T. capitatus on the growth of pathogenic bacteria associated with respiratory diseases (13 gram-positive and 4 gram-negative) were determined using a microdilution method. The MF was particularly effective on Streptococcus pneumoniae and Moraxella catarrhalis. The antioxidant activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), ferric-reducing antioxidant power and β-carotene bleaching assays. A strong activity using β-carotene bleaching test was observed with the MF (IC50 of 0.7 μg/mL after 30 min of incubation). In the hypoglycaemic test, a selective α-amylase inhibitory activity was detected with the HF begging the most active (IC50 of 422.5 μg/mL). T. capitatus may represent a source of natural bioactive compounds.

Insights into chitosan hydrogels on dentine bond strength and cytotoxicity

Contemporary dental adhesives show favorable immediate results in terms of bonding effectiveness. However, the durability of resin-dentin bonds is their major problem. Materials and Methods: Preparation of 3 chitosan-antioxidant hydrogels was achieved using modified hydrogel preparation method. Their effect on the bond strength to dentine both short term (after 24 hours) and long term (after 6 months) were evaluated using shear bond strength measurements using Instron Universal Testing Mascine). The SEM was used to study the surface of the hydrogels. The cell survival rate (cytotoxicity) of the antioxidants resveratrol, β-carotene and propolis towards Balb/c 3T3 mouse fibroblast cells was also assessed using the standard MTT assay. Results: It was found that chitosan-H treated dentine gives significantly (p β-carotene (92%) > propolis (68%) > resveratrol (33%). Conclusion: the antioxidant-chitosan hydrogels significantly improved bonding to dentine with or without phosphoric acid treatment. The pH of the growth medium had a high influence on the cell survival rate of Balb/c mouse 3T3 fibroblast cells. The release of the antioxidant β-carotene would not have an influence on the pulp cells. These materials might address the current perspectives for improving bond durability.

Determinants of Urolithiasis in Patients With Intestinal Fat Malabsorption

To investigate the determinants of urinary stone formation in patients with fat malabsorption, because, although the prevalence of urolithiasis is greater in patients with intestinal diseases, the pathogenetic mechanisms and risk factors associated with urolithiasis in this population remain partially unsolved. The present study retrospectively analyzed the determinants of urolithiasis in 51 patients with fat malabsorption due to different intestinal diseases. Anthropometric, clinical, blood, 24-hour urinary parameters, and dietary intake were assessed. The resection rate (ie, pancreatic and/or bowel resection) differed significantly between stone formers (SF; n=10) and nonstone formers (NSF; n=41; 70% vs 29%; P=.027). Urinary citrate was lower (1.606±1.824 vs 3.156±1.968 mmol/24 h; P=.027), while oxalate excretion (0.659±0.292 vs 0.378±0.168 mmol/24 h; P=.002) and the relative supersaturation of calcium oxalate were greater in SF than NSF (8.16±4.61 vs 3.94±2.93; P=.003). Total cholesterol and low-density lipoprotein cholesterol, but also high-density lipoprotein cholesterol, plasma β-carotene, and vitamin E concentrations, were significantly diminished, whereas serum aspartate aminotransferase activity was significantly greater in SF compared with NSF. Binary logistic regression analysis revealed resection status as a major extrarenal risk factor for stone formation (odds ratio 5.639). Increased urinary oxalate and decreased citrate excretion, probably resulting from pancreatic and/or bowel resection with mainly preserved colon, were identified as the most crucial urinary risk factors for stone formation in patients with fat malabsorption. The findings suggest that hyperoxaluria predominantly results from increased colonic permeability for oxalate due to disturbed bile acid metabolism. The impaired status of fat-soluble antioxidants β-carotene and vitamin E indicates severe malabsorptive states associated with an enhanced stone-forming propensity.

Comparison of bioactive components in fresh, pressurized, pasteurized and sterilized pennywort (Centella asiatica L.) juices

The biologically active constituents of pennywort juice were analyzed by HPLC. The juice extract contained the bioactive glycosides, including asiaticoside and madecassoside. Antioxidant properties of juices were determined in terms of ferric-reducing antioxidant power assay, total polyphenol, β-carotene and ascorbic acid contents. After processing, asiaticoside, madecassoside and β-carotene in the extracted juice were relatively stable with no significant losses occurring. Pressurization could significantly retain ascorbic acid, polyphenols and antioxidant capacity than those pasteurization or sterilization. For storage assessment, asiaticoside in the processed juices was relatively stable during 4 months storage. Losses of ascorbic acid in the pressurized juice during storage were greater than in pasteurized and sterilized juice. However, the total amount of ascorbic acid retained in pressurized juice was still higher than those thermal-treated products.

Destruction of Raman biosignatures by ionising radiation and the implications for life detection on Mars

Raman spectroscopy has proven to be a very effective approach for the detection of microorganisms colonising hostile environments on Earth. The ExoMars rover, due for launch in 2018, will carry a Raman laser spectrometer to analyse samples of the martian subsurface collected by the probe's 2-m drill in a search for similar biosignatures. The martian surface is unprotected from the flux of cosmic rays, an ionising radiation field that will degrade organic molecules and so diminish and distort the detectable Raman signature of potential martian microbial life. This study employs Raman spectroscopy to analyse samples of two model organisms, the cyanobacterium Synechocystis sp. PCC 6803 and the extremely radiation resistant polyextremophile Deinococcus radiodurans, that have been exposed to increasing doses of ionising radiation. The three most prominent peaks in the Raman spectra are from cellular carotenoids: deinoxanthin in D. radiodurans and β-carotene in Synechocystis. The degradative effect of ionising radiation is clearly seen, with significant diminishment of carotenoid spectral peak heights after 15 kGy and complete erasure of Raman biosignatures by 150 kGy of ionising radiation. The Raman signal of carotenoid in D. radiodurans diminishes more rapidly than that of Synechocystis, believed to be due to deinoxanthin acting as a superior scavenger of radiolytically produced reactive oxygen species, and so being destroyed more quickly than the less efficient antioxidant β-carotene. This study highlights the necessity for further experimental work on the manner and rate of degradation of Raman biosignatures by ionising radiation, as this is of prime importance for the successful detection of microbial life in the martian near subsurface.

Whey protein capsules obtained through electrospraying for the encapsulation of bioactives

Abstract In this work it is shown, for the first time, the potential of the electrospinning (in this case electrospraying) technique to generate whey protein concentrate (WPC) micro-, submicro- and nanocapsules for applications in the encapsulation of bioactives of interest in the development of novel functional foods. Furthermore, the solvent used for the development of the encapsulation morphologies was water, making these materials suitable for food applications. The WPC concentration for capsule formation was optimized and the effect of pH and addition of glycerol in the morphology and molecular organization of the capsules was studied. The results demonstrated that electrosprayed WPC capsules can be obtained for a wide pH range and for some glycerol concentrations and both factors had an effect on capsule size and conformation. Finally, the usefulness of the WPC capsules was demonstrated through the encapsulation of the antioxidant β-carotene. Industrial relevance As a response to the industrial demand for novel encapsulation technologies that protect sensitive ingredients, we present here an electrospraying process, which does not require the use of high temperatures, to generate WPC capsules from aqueous solutions. Moreover, the use of WPC as an encapsulating matrix has barely been explored, although it has a great potential due to the excellent functional characteristics of this protein mixture and its low cost.

Dietary patterns of 11-year-old children and associations with nutrient intakes

Background: The majority of studies looking at diet–disease relationships have mainly concentrated on individual nutrients or foods. Recently, the popularity of using dietary patterns, which evaluates the diet as a whole opposed to individual nutrients to assess diet–disease relationships, has increased. However, few studies have assessed the relationship between dietary patterns and nutrient intakes. In this study, the principal component analysis (PCA) method was used to determine the dietary patterns of 11-year-old children and how these were related to nutrient intakes. Methods: Children participating in a population-based birth cohort study (n = 709; male 378) completed a food frequency questionnaire (FFQ) (adapted DietQ, Tinuviel Software, Anglesey, UK) nutrient intakes were calculated (QBuilder, Tinuviel Software, Anglesey, UK). All nutrient data were log-transformed and energy-adjusted. PCA (a quantitative method for data reduction to extract simplified patterns from correlated multi-item data) was applied to data collected by FFQ to determine dietary components. Component scores were used to test the validity of the dietary components with known predictors such as gender and socioeconomic status (SES) using analysis of variance. The relationship between these dietary components and nutrient intakes were assessed using Pearson's correlation. Results: A total of 73 items were retained in the PCA. A three component solution was chosen. Dietary components were termed Fruit (fresh and tinned fruit), Processed food (high fat processed foods) and Traditional (mixture of meat and vegetables). Higher SES was associated with higher scores for Fruit and Traditional components (P = 0.02 and P < 0.001, respectively) and lower scores for the Processed component (P < 0.001). Girls had significantly higher scores for the Fruit component than boys and lower scores for the Processed component (P < 0.001). The intakes of fats were significantly inversely associated with the Fruit component, whereas the opposite relationship is seen for the Processed component (Table 1). Antioxidant vitamins β-carotene, vitamin C and vitamin E had a positive relationship with the Fruit and Traditional components, whereas the inverse association was seen for the Processed component. Table 1. Correlation coefficients of dietary patterns and selected nutrients Component Total fat MUFA PUFA Saturated fat Retinol β-carotene Vitamin E MUFA, monounsaturated fat; PUFA, polyunsaturated fat; *P < 0.01, **P < 0.001. Fruit −0.35** −0.37** −0.12* −0.28** −0.11* 0.31** 0.23** Processed food 0.35** 0.44* 0.15** 0.26** −0.14** −0.35** −0.20** Traditional −0.08 −0.05 −0.01 −0.09 0.12* 0.46** 0.15** Discussion: The dietary patterns identified in this study are similar to those identified by others (Northstone & Emmett, 2008; Craig et al., 2010). To our knowledge, this is one of the first studies to evaluate the relationship between dietary patterns and nutrient intakes in British school children. The results from this study suggest that, when dietary patterns are compared, then patterns of nutrient intakes are also being compared. This is an important consideration because nutrients are not consumed individually, yet the majority of focus of diet-disease relationships has been to evaluate the relationship between individual nutrient and disease. Conclusions: Dietary patterns, derived using PCA, are a method for assessing patterns of dietary and nutrient intakes and may provide a useful method to evaluate diet–disease relationships.

The Effect of β-Carotene Against Adriamycin Toxicity on the Embryo Formation

Adriamycin is an anthracycline antibiotic widely used for the treatment of many types of cancer. The cytotoxic effect of Adriamycin occurs by a free radical-mediated mechanism. Thus, to prevent or reduce the toxic effect of Adriamycin, it is possible to use it in combination with antioxidants. The aim of this study was to evaluate a potential effect of β-carotene against Adriamycin-induced toxicity on the embryo formation. Pregnant rats were treated with Adriamycin, β-carotene, and their combination during the critical stages of embryogenesis. The first group was control group. Adriamycin was administered on day 9 (group 2a) and day 12 (group 2b) of gestation by a single intraperitoneal injection at a dose of 5 mg/kg. β-Carotene was given at a dosage of 0.6 mg/(kg·day) from day 6 to 10 or from day 9 (group 3a) to 13 (group 3b) of gestation 5 times per os; in the case of their combination, β-carotene was given per os 3 times before Adriamycin injection, one time simultaneously with Adriamycin and one time after its injection (groups 4a and 4b). Animals were euthanized on day 21 of gestation. Embryo resorptions and alive fetuses were counted, weighed, and measured. The embryos of each litter were examined macroscopically after the Buen solution fixation for the embryo defects. In order to render the skeleton visible, the soft tissues were macerated using caustic soda, stained with alizarin red, and cleared with glycerin. Adriamycin induced embryotoxicity; the combination of Adriamycin and β-carotene decreased the number of Adriamycin-induced embryo resorptions about two times. A gavage with Adriamycin alone decreased fetal body weights (P<0.05), while giving it in combination, the fetal body weight was similar to that in the control group. Adriamycin induced the retardation of skeletogenesis and external fetal malformations (microphthalmia, hydrocephaly, anencephaly, and others). After an exposure to β-carotene, external malformations (diaphragmatic hernia) of embryos were found only occasionally. β-Carotene in combination with Adriamycin produced no positive effect on Adriamycin-induced skeletodysgenesis or external malformations. Antioxidant β-carotene in combination with Adriamycin slightly reduced the Adriamycin-induced embryotoxicity, but produced no positive effect on Adriamycin-induced skeleto-dysgenesis or external malformations.

The Impact of Acute Moderate Intensity Exercise on Arterial Regional Stiffness, Lipid Peroxidation, and Antioxidant Status in Healthy Males

There is a paucity of research examining the influence of acute exercise on pulse wave velocity (PWV) and oxidative stress. The purpose of this study was to examine the effects of acute moderate aerobic exercise on PWV and oxidative stress in healthy males. Eight apparently healthy males (age 23.6 ± 2.8 yrs; stature 181.4 ± 8.1 cm; weight 83.4 ± 16.2 kg; all data mean ±SD) participated in a randomized crossover design consisting of (i) a one hour bout of moderate aerobic exercise and (ii) a control trial of one hour rest. Pre- and post-exercise blood samples were drawn for the determination of lipid hydroperoxides (LOOHs) and lipid-soluble antioxidants (lycopene, retinol, and β-carotene). Exercise had no effect on stiffness and LOOHs (P > 0.05). Retinol and lycopene were increased following exercise (P < 0.05). These findings suggest that acute moderate exercise has no effect on PWV and LOOHs, but it can increase systemic antioxidants, which may be of benefit to health.

Cytogenetic study of the effect of Schistosoma mansoni infection on human peripheral blood lymphocytes and the role of β-carotene and vitamin E in modulating this effect

This study has been made to determine the potential genotoxicity of Schistosoma mansoni on lymphocytes of infected patients using different mutagenic end points. The protective role of antioxidants pro vitamin β-carotene and vitamin E in minimizing these genotoxic effect was also studied. The study focused on the effect of schistosomiasis on the induction of sister chromatid exchange (SCEs) and other chromosomal aberrations. This work was conducted on 24 Schistosoma mansoni infected patients and 10 healthy adults as a control group. Lymphocytes from peripheral blood of patients and control group were used for culture and subsequent cytogenetic studies. The results indicated that schistosomiasis was genotoxic in all examined tests. It induced a significant increase in the percentage of structural chromosomal aberrations and the frequency of SCEs. It also inhibited cell division and caused cell cycle delay. Lymphocyte cultures of S. mansoni patients treated with 10 μg/ml β-carotene or 20mg/ml vitamin E showed a significant decrease in the percentage of structural chromosomal aberrations and the frequency of SCEs. Schistosomiasis has a genotoxic effect on peripheral blood lymphocytes. The use of the antioxidants β-carotene and vitamin E can be considered a promising approach not only toward inhibiting the genetic damage of schistosomiasis but also as prophylactic agents against infection with S mansoni. Furthermore, higher doses of antioxidant drugs, β-carotene and vitamin E, should be tried as an adjuvants to conventional therapy in a trial to improve treatment of schistosomiasis.

Improved incorporation and stabilisation of β-carotene in hydrocolloids using glycerol

In this paper, a novel method for the incorporation of the antioxidant β-carotene in hydrocolloid matrices is presented, which consists on the use of glycerol as the vehicle for incorporation. This alcohol has been observed to greatly photostabilise the carotenoid molecule within the hydrocolloid matrices without greatly affecting the mechanical properties of the materials. The UV stability of β-carotene in the different hydrocolloid films developed (including starch, soy protein, whey protein concentrate, gelatin and zein) has been studied using UV/visible spectrophotometry, colorimetry and Raman spectroscopy. Raman images of the materials were also generated in order to ascertain the dispersion of the antioxidant within the hydrocolloid materials and it was observed that β-carotene was partially agglomerated in certain areas of the film, fact that could also contribute to enhance the stability of the bioactive molecule.

Beta-carotene suppression of benzophenone-sensitized lipid peroxidation in hexane through additional chain-breaking activities

The aim of this work is to estimate the antioxidant activity of β-carotene in the presence of two different mixtures of phospholipids in hexane solution, under continuous UV-irradiation from three different ranges (UV-A, UV-B, and UV-C). β-Carotene is employed to control lipid peroxidation process generated by UV-irradiation, in the presence and in the absence of selected photosensitizer, benzophenone, by scavenging the involved, created free radicals. The results show that β-carotene undergoes to a substantial, probably structural dependent destruction (bleaching), highly dependent on UV-photons energy input, more expressed in the presence than in the absence of benzophenone. The additional bleaching is synchronized with the further increase in β-carotene antioxidant activity in the presence of benzophenone, implying the same cause: increase in (phospholipids peroxidation) chain-breaking activities.

Dietary lipids may protect the retina against age‐related macular degeneration

AbstractAge‐related macular degeneration (AMD) is the leading cause of visual loss in the Western World. It is a disease of the retina probably initiated by the highly oxidising environment of this tissue. The Age‐Related Eye Disease Study (AREDS) demonstrated in 2001 that a supplement of the antioxidants β‐carotene, vitamin E, vitamin C and the minerals zinc and copper can slow down the progression of AMD. The use of this supplement should be standard practice in all countries. It is known that the carotenoids lutein and zeaxanthin and the very long chain n‐3 polyunsaturated fatty acid docosahexaenoic acid (DHA) play special roles in protecting the retina against oxidative damage and there is some evidence from epidemiological studies that these nutrients slow down the progression of AMD. AREDS 2 a randomised controlled trial is testing the ability of DHA, lutein and zeaxanthin to slow down the progression of AMD. Until this study is complete in 2012 AMD patients should consider taking a supplement corresponding to the AREDS 2 formulation as a precaution.

Radical Production by Infrared A Irradiation in Human Tissue

The influence of the ultraviolet (UV) irradiation of the sun on the formation of free radicals in human skin is well investigated. Up to now, only small amounts of data are available stating that infrared (IR) irradiation can produce free radicals in the skin. In the present study, the formation of free radicals in human skin, subsequent to IRA irradiation (600–1,500 nm), has been demonstrated by means of two different methods. Firstly, the radical formation was detected indirectly by the degradation of the cutaneous carotenoid antioxidants β-carotene and lycopene, which was investigated in vivo by resonance Raman spectroscopic measurements. Secondly, the direct observation of produced radicals subsequent to IRA irradiation of the skin was performed in vitro by electron paramagnetic resonance spectroscopy. Taking into account the results of the present study and previous UV light studies, it can be expected that also solar irradiation in the visible spectral range will produce free radicals in the human skin. Therefore, the current sun protection strategies should be reconsidered. Furthermore, it was shown in the present study that the side effect in the form of radical formation could be significantly reduced by increasing the protection system of the human organism in form of the antioxidant network.

Pivotal role of curcuminoids on the antimutagenic activity of Curcuma zedoaria extracts

In an investigation of the mutagenic activity of two extracts from rhizomes of Curcuma zedoaria (the mathanolic, CME, and the aqueous, CAE) and antimutagenic activity against mutagens, either 2-amino-3-methylimidazo (4,5-f) quinoline (IQ) or 4-nitroquinoline-N-oxide (4-NQO), in dosages of 1–50 μg/plate was assayed by using Salmonella typhimurium TA97, TA98, TA100, and TA102 strains. We found that the two extracts showed no mutagenicity when tested with all the tester strains either with or without the S9 mix. Moreover, the two extracts, particularly CME, presented a greater antimutagenicity than CAE did either in IQ or 4-NQO mutagens. However, the inhibition effect on lipid peroxidation was similar with both extracts. The amount of major antioxidants β-carotene, ascorbic acid, and total polyphenols present in both CME and CAE were similar between each other. In contrast, the content of cucuminoids (44.3 mg/g extract) in CME were only found in small amounts in CAE (0.09 mg/g extract). Consequently, although both of the extracts showed similar antioxidant effects, the curcuminoids, which seem to be the main active principles from this plant, were suggested to play a pivotal role in antimutagenic activity.

Effects of a phytosterol-enriched dairy product on lipids, sterols and 8-isoprostane in hypercholesterolemic patients: A multicenter Italian study

Background and aims Plant sterols, added to several food sources, lower serum cholesterol concentrations. Plant sterol-induced cholesterol lowering is paralleled by a mild decrease in plasma levels of the antioxidant β-carotene, the amount of this decrease being considered clinically non-significant. Whether the effect on lipid profile of daily consumption of plant sterol-enriched low-fat fermented milk (FM) is paralleled by a concomitant variation in a reliable marker of the oxidative burden like plasma isoprostane levels is unresolved. Methods and results The effect of plant sterol consumption on plasma lipid and isoprostane levels of hypercholesterolemic patients was evaluated in a multicenter, randomized double blind study. Hypercholesterolemic patients consumed a FM daily for 6 weeks. Subjects were randomized to receive either 1.6 g of plant sterol-enriched FM ( n = 60) or control FM product ( n = 56). After 6 weeks of plant sterol-enriched FM consumption, LDL cholesterol was reduced from 166.2 ± 2.0 to 147.4 ± 2.8 mg/dL ( p = 0.01). A significant reduction was observed for total cholesterol (from 263.5 ± 2.6 to 231.0 ± 3.2 mg/dL, p = 0.01). There was greater LDL cholesterol lowering among hypercholesterolemic patients with higher LDL cholesterol at baseline. We found a reduction of plasma 8-isoprostane in patients taking plant sterol-enriched FM (from 43.07 ± 1.78 to 38.04 ± 1.14 pg/ml, p = 0.018) but not in patients taking the control product (from 42.56 ± 2.12 to 43.19 ± 2.0 pg/ml, p = NS). Campesterol and β-sitosterol levels were not influenced by phytosterol consumption. Conclusions Daily consumption of low-fat plant sterol dairy product favourably changes lipid profile by reducing LDL-cholesterol, and may also have an anti-oxidative effect through a reduction of plasma isoprostanes.