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Background and Aims Grape maceration plays an important role in the formation of precursors of 3-mercaptohexan-1-ol ( 3MH), 3- S-glutathionyl mercaptohexan-1-ol ( GSH- 3MH) and 3- S-cysteinyl mercaptohexan-1-ol ( Cys- 3MH), but its contribution is still not well understood. The aim of this paper was to study the effect of oxygen deprivation on the concentration of these 3MH precursors during skin-contact maceration in two grape cultivars. Methods and Results Müller- Thurgau ( n = 19) and Sauvignon Blanc (32) grapes from Trentino ( Italy) were hand harvested and processed under the following conditions: reductive (air protected; 80 mg/kg sulfur dioxide, 80 mg/kg L-ascorbic acid, and 200 mg/kg dimethyl dicarbonate) and oxidative (no addition of adjuvants and air contact). After maceration, GSH- 3MH and Cys- 3MH were analysed by liquid chromatography-mass spectrometry and isotopic dilution. Conclusions Both GSH- 3MH and Cys- 3MH were identified for the first time in Müller- Thurgau juices. Oxidative maceration increased the GSH- 3MH concentration in 16 out of 19 Müller- Thurgau and in 23 out of 32 Sauvignon Blanc juices, while Cys- 3MH was higher in 13 and 20 juices, respectively, of the two cultivars. Parametrical and non-parametrical statistical tests confirmed that oxidative maceration of Müller- Thurgau increased GSH- 3MH concentration significantly ( P < 0.01). Significance of the Study This work highlights the complexity of the mechanisms involved in the potential de novo formation of thiol precursors. [ABSTRACT FROM AUTHOR]

ABSTRACT The objective of the study was to investigate the stability of polyphenols and ascorbic acid in osmo-dried fruits: apples, sour cherries and blackcurrants, stored for 12 months. After 1 year of storage, the content of total polyphenols and anthocyanins in convectively dried blackcurrants was decreased by 45% and 90%, respectively. Flavonols remained highly stable. Convectively dried sour cherries contained particularly labile substances, including cyanidin derivatives, which content decreased by 98% after 6 months. Polyphenols in freeze-dried materials were more stable. After 1 year of storage, their content remained at 60-80% of the initial level. A high stability was in particular observed for delphinidin-3-rutinoside in blackcurrants, and cyanidin derivatives, chlorogenic acid, neochlorogenic acid and quercetin glucoside in sour cherries. The stability of ascorbic acid was also much higher in freeze-dried blackcurrants than in convectively dried fruit. After 1 year of storage, almost 70% of ascorbic acid was preserved in freeze-dried material. PRACTICAL APPLICATIONS Analyzed material was obtained in industrial conditions. Final products were used to produce bars; it can also be used in manufacturing of muesli and similar products. The results of performed analyses show a change in the content of polyphenols and ascorbic acid during product storage and could be useful to define the time in which a product is characterized by the highest content of health-promoting substances. [ABSTRACT FROM AUTHOR]

ABSTRACT The effect of waxing and wrapping on fruit quality, phenolic compounds and antioxidant activity of two citrus cultivars (Satsuma mandarin [ Citrus unshiu Marc] and Hamlin orange [ Citrus sinensis Osbeck cv Hamlin]) stored at 10 ± 2C for 60 days was investigated. Ascorbic acid, flavanone glycosides, phenolic acids, total phenolics and antioxidant activity (ferric-reducing antioxidant power assay and 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging assay) were determined. During storage, phenolic compounds were relatively stable. Antioxidant activity was influenced by both ascorbic acid and phenolic compounds. Generally, wrapping fruits retained higher levels of flavanones and phenolic acids during storage while waxing was not preferable in preserving phenolic compounds especially after 30 days. Besides, waxing and wrapping retained higher levels of total phenolics after 15 days of storage in both cultivars. PRACTICAL APPLICATIONS Recently, phenolic compounds of citrus fruits have gained much concern because of their benefits to human health. However, studies on changes of detailed phenolic components during postharvest storage are limited. The effect of waxing and wrapping on phenolic compounds and antioxidant activity of Satsuma mandarin ( C. unshiu Marc) and Hamlin orange ( C. sinensis Osbeck cv Hamlin) during storage are presented in this study. The results show that the two citrus cultivars maintained their functional value because of the stability of phenolic compounds during storage. Wrapping preserved higher levels of phenolic content with improved fruit appearance thus is better for marketing and consumption. While waxing had negative effects on keeping functional quality of fruit after long-time storage. The findings may also be useful for a better understanding of changes in specific phenolic compounds in citrus fruits during postharvest storage. [ABSTRACT FROM AUTHOR]

This study investigated the effects of the co-supplementation of vitamins C (0, 500, and 1000 mg kg−1) and E (0, 62.5, and 125 mg kg−1) on the growth performance, haematology and the modulation of blood stress indicators and immune parameters in hybrid catfish ( Clarias macrocephalus × Clarias gariepinus) under combinations of thermal and acidic stress. Supplementation of vitamins C and E influenced the growth, haematological indices, serum chloride, plasma protein and immune parameters (lysozyme, total immunoglobulin and alternative complement haemolytic assay) ( P < 0.05). Although vitamins C and E did not prevent a significant reduction in serum chloride, they minimized not only the modulation of blood glucose and plasma protein, but also the reduction in immune parameters ( P < 0.05) owing to stress. Our results demonstrated that co-supplementation of 500 mg kg−1 vitamin C and 125 mg kg−1 vitamin E, or 1000 mg kg−1 vitamin C alone, for four weeks and co-supplementation of both vitamins at low levels (vitamins C at 500 mg kg−1 and E at 62.5 mg kg−1) for eight weeks had beneficial effects on the growth, amelioration of stress-mediated adverse changes in the physiological and immunosuppressive responses of hybrid catfish under stressful conditions. [ABSTRACT FROM AUTHOR]

The effect of ascorbic acid and N2 usage in large-scale cloudy apple juice production was investigated. Samples were stored at 5 and 20 C for 6 months. The quality of the initial cloudy apple juice samples was evaluated by characteristic properties ( pH, total titratable acidity, total dry matter, soluble solids and total phenolic content) and storage stability was evaluated by turbidity and color parameters, which were analyzed on a monthly basis. According to the results, change in total phenolic content of the samples was considerable (minimal values were recorded in N2-treated groups). However, ascorbic acid and N2 usage alone or in combination was not enough to prevent turbidity loss during storage. Only the lower temperature (5 C) chosen was effective to decelerate this loss. In terms of color stability, the most stable group was the N2 and ascorbic acid-treated one (Δ E: 3.59 at 5 C). Practical Applications Color and cloud stability are important attributes of cloudy apple juice during storage. Many laboratory studies have been conducted to improve these quality parameters. However, there is no large-scale study about the storage stability of cloudy apple treated by N2 and ascorbic acid during the production stages. Therefore, in this study, a large-scale cloudy apple juice production was performed using N2 and ascorbic acid during the juice processing stage and the storage stability of the final products was investigated for 6 months. The results of this large-scale study could be useful for fruit juice processors and retailers. [ABSTRACT FROM AUTHOR]

ABSTRACT This study aimed at evaluating the quality changes and decay rate of antioxidant compounds during long-term storage (330 days) of frozen purée from different acerola clones: BRS 235, BRS 236, BRS 237, BRS 238, II47/1 and BRS 152. The soluble solids/titrable acidity ratio was relatively stable during storage. All clones, except BRS 236, showed great loss of anthocyanin after 180 days of storage; although in general, they presented high levels of anthocyanins. For most clones, there was a direct correlation between vitamin C and anthocyanin decay rates and for these, it is possible that the decay in anthocyanin content is linked to the reaction between anthocyanin and vitamin C or, most probably, by-products of vitamin C degradation. Overall, processing of acerola purées resulted in alternative products with good quality and clones BRS 238 and II 47/1 had the best performances. PRACTICAL APPLICATIONS Acerola is a rich source of antioxidants such as ascorbic acid and anthocyanins and, as most tropical fruits, it has a very short postharvest life. Thus, processing acerola pulp and storing it at low temperatures are fundamental for extending storage life and preventing decay. This research describes original and important information on the kinetics of degradation of anthocyanin and vitamin C, both nutritionally relevant compounds, during the storage of frozen fruit pulp. This study has potential application in the fruit processing industry as a valuable tool for the optimization of conservation and for the attainment of a better quality product. [ABSTRACT FROM AUTHOR]

A 50-day feeding trial was conducted to determine the effects of dietary oxidized fish oil ( OFO) and vitamin C ( VC) on growth and oxidative stress in juvenile red sea bream. Test diets were formulated with 2 degrees of peroxide value (23 and 29 meq kg−1) combined with 3 levels of VC (0, 400 and 800 ppm). No significant difference was found on growth performance between fish fed OFO with 400 or 800 mg VC and the control group that fed a diet with fresh fish oil after 50 days. However, fish fed OFO without VC supplement indicated significantly poor growth than the control group. Liver and muscle thiobarbituric acid reactive substances were reduced by increased VC intake of fish. Fish fed diets containing low OFO with 400 and 800 mg VC, high OFO with 800 mg VC, and fresh fish oil are allocated in the zone of high resistance against oxidative stress together with low oxidative stress condition. On the other hand, no VC supplemented group was under the highest oxidative stress condition. In conclusion, dietary oxidized lipid increased the oxidative stress condition of fish, but more than 400 mg VC kg−1 of dietary supplement improved growth and health of juvenile red sea bream. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects of practical diets with different levels of vitamin C on survival and growth of juvenile crayfish ( Pacifastacus leniusculus). An 80-day trial was conducted with stage 2 juveniles from the onset of exogenous feeding. Four practical diets differing in the content of l-ascorbyl-2-monophosphate- Na were prepared: 0, 0.2, 0.4 or 0.8 g kg−1 diet. Each diet was tested on grouped or individually isolated crayfish. Diets had no significant effects on survival of crayfish held in groups (average: 73.1%) neither on the isolated ones (average: 90%). Crayfish fed the diet with 0.2 g kg−1 of l-ascorbyl-2-monophosphate- Na had the highest growth (groups: 13.64 mm carapace length ( CL), 542.4 mg weight; isolated: 17.05 mm CL, 1213.2 mg weight) and the lowest feed conversion ratio (average of grouped and isolated: 0.99). This study provides the first data on vitamin C requirements of freshwater crayfish. A level of 0.2 g l-ascorbyl-2-monophosphate- Na kg−1 diet (0.07 g ascorbic acid equivalent) can be recommended for juvenile P. leniusculus during the first period of intensive rearing. [ABSTRACT FROM AUTHOR]

L-Ascorbic acid (vitamin C) is as essential to plants as it is to animals. Ascorbic acid functions as a major redox buffer and as a cofactor for enzymes involved in regulating photosynthesis, hormone biosynthesis, and regenerating other antioxidants. Ascorbic acid regulates cell division and growth and is involved in signal transduction. In contrast to the single pathway responsible for ascorbic acid biosynthesis in animals, plants use multiple pathways to synthesize ascorbic acid, perhaps reflecting the importance of this molecule to plant health. Given the importance of ascorbic acid to human nutrition, several technologies have been developed to increase the ascorbic acid content of plants through the manipulation of biosynthetic or recycling pathways. This paper provides an overview of these approaches as well as the consequences that changes in ascorbic acid content have on plant growth and function. Discussed is the capacity of plants to tolerate changes in ascorbic acid content. The many functions that ascorbic acid serves in plants, however, will require highly targeted approaches to improve their nutritional quality without compromising their health. [ABSTRACT FROM AUTHOR]

The objective of this study was to understand the usage patterns of dietary supplements among professional athletes in Saudi Arabia. The survey consisted of sixteen questions divided into four categories: use of supplements, reason for consumption of supplements, personal beliefs about supplements, and behavior. The questionnaires were given to the three teams residing in Riyadh: Al Hilal, Al Nasr, and Al-Shabab. Out of the 105 athletes surveyed, we found that only 98 are currently taking dietary supplements and the mean age and standard deviation were 25.74 ± 2.90.The survey results showed a high percentage of athletes (93.3%; n = 98) using different dietary supplements throughout the season, 43.8% (n = 43) reported using supplements for performance, and 32.6% (n = 32) believed in health benefits as a reason for using dietary supplements. Our results showed that a total of 87 (88.7%), 81 (82.6%), and 51 (52.0%) athletes are consuming sports drinks, vitamin C, and multivitamins, respectively. Meanwhile, those supplements ranking among the least used included omega 6 (18.6%), creatine (16.3%), and Ginkgo biloba (10.2%). A majority of athletes indicated that their use of supplements was for the purpose of improving their health and performance. [ABSTRACT FROM AUTHOR]

Reference interval of all haematological and biological analytes should be measured for every population because of the huge diversity in genetic make-up, dietary habits. The coverage interval of antioxidant vitamins (vitamin C and α-tocopherol) in the plasma and serum of reference Bengali population was determined and compared with the reference intervals of antioxidant vitamins in the established literature. Adult healthy volunteers from 18 to 68 years of age underwent extensive clinical and investigational procedure and were included in the study. Vitamin C and α-tocopherol were estimated using simple Spectrophotometric method. Of the 71 healthy Bengali volunteers participated, 31 were males and 40 were females. The mean concentration of plasma vitamin C was found to be 0.65mg/dL. The mean α-tocopherol was found 6.35mg/L (14.74 Μmol/L) in the study population higher than the normal threshold value for α-tocopherol but lower than other populations. The study data enabled us to determine the gender nonspecific coverage interval of antioxidant vitamins, and the intervals were lower than the established reference interval in other populations. [ABSTRACT FROM AUTHOR]

ABSTRACT Retarding browning and softening of fresh-cut mangosteen during storage under modified atmosphere packaging (MAP) by pretreatment with preservative dips was investigated. Mangosteens at stage 1 of maturity were peeled and immersed for 30 min in different mixed solutions including 2% sodium erythorbate + 0.2% calcium chloride (CaCl2), 1% aluminium sulfate + 1% sodium chloride (NaCl), 1% ascorbic acid (AA) + 1% NaCl + 1% CaCl2 and 1% citric acid + 1% NaCl + 1% CaCl2 prior to active MAP (5% O2 + 9% CO2) using low-density polyethylene bag. Quality changes of the fresh-cut mangosteens were monitored during storage at 4C for up to 12 days. The fruit treated with 1% AA + 1% NaCl + 1% CaCl2 exhibited the best quality of appearance and texture in terms of lightness, firmness, weight loss, exudation and sensory score during the storage. However, in-package atmospheric compositions of all treatments were similarly developed throughout the storage. PRACTICAL APPLICATIONS Consumption of fresh-cut mangosteen has been increasing rapidly due to its unique lusciousness. However, discoloration and firmness loss of the product are crucial limiting factors to acceptability by consumers. Chemical treatment with the mixed solution of 1% ascorbic acid + 1% sodium chloride + 1% calcium chloride has high potential for practical applications due to its effectiveness in maintaining appearance and texture of the product. Furthermore, the use of inexpensive preservative results in reducing production cost. [ABSTRACT FROM AUTHOR]

Fish meal, vitamin C and fish oil are known to play essential roles in reproduction and immunity in animals. To investigate how the diet affect reproduction under the condition of reducing costs, we designed an experimental diet that decreased the ratio of fish meal with soybean meal from 1:1 to 1:1.5, and supplemented with 0.06% vitamin C and 3.8% fish oil for the crayfish, P rocambarus clarkii. After a 100-day feeding experiment, female crayfish fed the test diet had significantly greater gonadosomatic index ( GSI) compared with those fed the basal diet ( P < 0.05). At the middle stage of ovarian development, the test diet gave significantly higher trypsin-specific activity (340.94 ± 57.32 U mg−1 protein) in hepatopancreas of the crayfish than the basal diet (89.48 ± 10.01 U mg−1 protein) ( P < 0.05). However, hepatosomatic index ( HSI) was remarkably decreased for those females fed test diet ( P < 0.05). In addition, the experimental diet resulted in markedly lower superoxide dismutase ( SOD) activity and malonaldehyde ( MDA) levels, especially in the ovaries ( P < 0.01). These results suggest that dietary reduction of fish meal, supplementation of appropriate amounts of vitamin C and fish oil may promote ovary development probably by increasing digestibility, as well as by promoting transferring of nutrients from hepatopancreas to ovary and raising immunity of P . clarkii. [ABSTRACT FROM AUTHOR]

Aqueous extractions from two species of Erica consumed as infusions in several countries to heal ailments were investigated for their phenolic and flavonoid contents, along with antioxidant capacity and radical scavenging capacity using total antioxidant activity, ferric-reducing antioxidant power, reducing power, 1,1-diphenyl-2-picrylhydrazyl and 2-2'-azino-bis(3 ethylbenzothiazoline-6-sulfonic acid) radicals, respectively. Antioxidant properties and total phenolic content differed significantly among these plants. Aqueous extracts of leaves possessed, on average, the highest antioxidant capacity and phenolic content (34.09 ± 10.81 mg ascorbic acid equivalent/g dry weight and 30.59 ± 10.19 mg gallic acid equivalent/g dry weight, respectively) of all three plant parts. A significant correlation ( r2 = 0.952) between antioxidant capacity and total phenolic content was found, indicating that phenolic compounds are the major contributors to the antioxidant properties of these plants. Upon application of hierarchical cluster analysis to the results obtained, leaves with flowers were grouped in one cluster, whereas branches remained in another cluster, showing little interference from the collection site or species factors. Practical Applications Results obtained support that there may exist benefits for health from ingesting this plant infusions and that these plants have a great potential to serve as a cheap antioxidant source. [ABSTRACT FROM AUTHOR]

What is known and Objective: Helicobacter pylori eradication rates of currently accepted triple therapy regimens vary between geographic locations and do not exceed 70-80%. Eradication rates are much lower in locations where uncontrolled antibiotic use is common such as Turkey. In the present study, we aimed to test whether supplementing vitamins C and E to standard triple therapy, including a proton pump inhibitor plus amoxicillin plus clarithromycin, increased the H. pylori eradication rate. Methods: Two hundred patients infected with H. pylori were randomized into two groups in an open-label trial. In group A, patients ( n = 160) were given standard triple therapy, including lansoprazole 30 mg BID plus amoxicillin 1000 mg BID plus clarithromycin 500 mg BID for 14 days, plus vitamin C 500 mg BID plus vitamin E 200 IU BID for 30 days. In group B, patients ( n = 40) were given standard triple therapy for 14 days. The success of H. pylori eradication was defined as a negative 14C-urea breath test result, 4-6 weeks after the completion of therapy. Comaprisons were by both intention-to-treat (ITT) and per-protocol (PP) analysis. Results and Discussion: Two hundred patients (137 women, 63 men) were analysed using ITT analysis and 195 patients completed the study. In group A, H. pylori eradication was achieved in 132 of the 160 patients (82·5%) included in ITT analysis and 132 of the 157 patients (84%) included in PP analysis. In group B, H. pylori eradication was achieved in 18 of the 40 patients (45%) included in ITT analysis and 18 of the 38 patients (47·4%) included in PP analysis. Eradication rates were significantly higher in group A than in group B ( P < 0·005). Eradication rates were not statistically significant between men and women in both groups. What is new and Conclusion: Adding vitamins C and E to standard triple therapy increases the eradication rate of H. pylori. Vitamins C and E may increase the eradication rate via increasing the effectiveness of the antibiotics by decreasing oxidative stress in the gastric mucosa and strengthening the immune system. [ABSTRACT FROM AUTHOR]

ABSTRACT Treatments to inhibit browning of fresh-cut apples were investigated. The color ( L*), the browning potential and polyphenol oxidase (PPO) activity of fresh-cut apples (Golden Delicious, Scarlet Spur and Granny Smith) were evaluated throughout cold storage. Antibrowning agents (citric and ascorbic acid) and calcium chloride resulted in a reduction of browning and deterioration of fresh-cut apples stored at 4C for 5 days under normal atmospheric conditions. During storage, PPO activity increased and was inhibited by the use of citric and ascorbic acids. These antibrowning agents helped to maintaining the color of fresh-cut apples during storage. On the contrary, the use of 1-methylcyclopropene was not effective to prevent the color deterioration of the apple slices from the first day of cold storage. PRACTICAL APPLICATIONS The ready-to-eat fruit and vegetable market has rapidly grown in recent years due to the health benefits associated with these foods because of busy lifestyles, increasing purchasing power and increasingly health-conscious consumers. Nevertheless, because the tissular integrity of fruits is more easily altered during processing, ready-to-use commodities are more perishable than the original materials to browning surface. The use of organic acids such as malic acid, as well as physicochemical quality-stabilizing compounds on fresh-cut fruits and vegetable can benefit the fresh-cut products industry since they can assure the safety and quality of these products. The data collected of this study demonstrated that treatments included 1% w/v of citric acid/CaCl2 and 1% of ascorbic acid/CaCl2 were effective inhibitors of browning surface. For practical purposes the results obtained, we recommend the use of ascorbic acid and citric acid to maintain the quality of fresh-cut apples. [ABSTRACT FROM AUTHOR]

ABSTRACT Nanocomposite low-density polyethylene (LDPE) films containing Ag and ZnO nanoparticles were prepared by melt mixing process through the twin-screw extruder. Packages prepared from nanocomposite films were then filled with fresh orange juice, pasteurized (at 55 and 65C for 16 s) and then stored at 4C. Microbial stability, ascorbic acid (AA) content, browning index and color value of the juice were evaluated after 7, 28, 56, 84 and 112 days of being stored. The two-way interaction between heat treatment and packaging type on the characteristics of the orange juice was investigated. Consequently, application of LDPE nanocomposite packaging containing Ag markedly decreased the pasteurization temperature (65C) of orange juice by 10C. Moreover, the reduced degradation of AA was observed in orange juice, which was filled in nanocomposite packaging containing nano-ZnO. PRACTICAL APPLICATIONS Development of the novel technologies that offer reduced energy consumption and increased quality of fruit juice are of the interest in the food industry. Compared with pure packaging, antimicrobial nanocomposite packages containing Ag and ZnO as an alternative nonthermal-processing technology can reduce the temperature of orange juice light pasteurization while produce juice with higher quality. [ABSTRACT FROM AUTHOR]

SUMMARY Aims: Essential hypertension, as well as other established cardiovascular risk factors, is associated with endothelial dysfunction. Hypertensive patients with a nondipper circadian pattern have a greater risk of cerebrovascular and cardiovascular complications in comparison with those with a dipper circadian pattern. In this study, we evaluated the association between nondipper pattern and endothelial function in patients with essential hypertension. Methods: We evaluated the forearm blood flow (FBF) response to intraarterial acetylcholine (ACh), an endothelium-dependent vasodilator, and sodium nitroprusside (SNP), an endothelium-independent vasodilator, infusions in 190 hypertensive patients stratified according to dipper and nondipper status. The FBF was measured by strain-gauge plethysmography. Effects of oxidative stress on FBF were evaluated by intraarterial infusion of vitamin C. Ambulatory BP monitorings were obtained by a validated oscillometric device (SpaceLabs 90207 Monitor Inc., Issaquah, WA, USA). Results: Systolic and diastolic blood pressures were higher during daytime and lower during night-time in dipper subjects than in nondippers. The peak percent increase in ACh-stimulated FBF was higher in dippers than in nondippers (473% vs. 228%, P < 0.001). The FBF responses to SNP were similar in dipper and nondipper patients. The FBF response to ACh during coinfusion of vitamin C was higher in nondippers rather than in dipper hypertensives. Conclusions: Present data demonstrate that endothelium-dependent vasodilation is impaired in patients who have nondipper hypertension. The effects of vitamin C on impaired ACh-stimulated vasodilation support the hypothesis that oxidative stress contributes to endothelial dysfunction of nondipper hypertensive patients. [ABSTRACT FROM AUTHOR]

Various efforts have been made in past in order to predict the underlying mechanism of pesticide-induced toxicity using in vitro and animal models, however, these predictions may or may not be directly correlated with humans. The present study was designed to investigate the carbofuran induced genotoxicity and its amelioration by vitamins C and E by treating human peripheral blood lymphocytes (PBLs) with different concentrations (0, 0.5, 1.25, 2.5, 3.75 and 5.0 μM) of this compound. The treatment of PBLs with carbofuran displayed significant DNA damage in concentration dependent manner. The carbofuran induced genotoxicity could be ameliorated to considerable extent by pretreatment of PBLs with equimolar (10 μM) concentration of each of the vitamins C and E; the magnitude of protection by vitamin E being higher than by vitamin C. Also, it was found that the level of protection by these vitamins was higher when PBLs were treated with lower concentrations of pesticide. The significant DNA damage as observed by H_{2}O_{2}, a positive control in the present study, and its amelioration by natural antioxidants (vitamins C and E) lend an evidence to suggest that carbofuran would have caused genotoxicity via pesticide induced oxidative stress. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, the changes in color, ascorbic acid, antioxidant activity and phenolic compounds of raspberry and blackberry cultivars after marmalade processing were evaluated. For this purpose, raspberry fruits ( Rubus idaeus L.) of four cultivars (Aksu Kırmızısı, Rubin, Hollanda Boduru and Heritage) and blackberry fruits ( Rubus fruticosus L.) of three cultivars (Bursa 1, Bursa 2 and Chester) were used. According to the results, color values of blackberry cultivars and marmalades were lower than the color values of raspberry. Raspberry cultivars were more durable to thermal processing than blackberry cultivars in terms of ascorbic acid degradation. An 84.19% decrease was seen in the antioxidant activity of raspberry and blackberry cultivars after marmalade processing. The marmalade produced from Hollanda Boduru had the highest antioxidant activity. Ellagic acid was predominant in all raspberry and blackberry cultivars and ranged from 727.90 ± 9.21 mg/kg (Rubin) to 1,828.07 ± 23.73 mg/kg (Chester). None of the phenolics was determined in marmalades. PRACTICAL APPLICATIONS Berry fruits constitute a good source of natural antioxidant substances. Particularly, phenolic compounds contribute substantially to the antioxidant complement of many small fruit species, having potential health effects. The main contribution of this work is to determine the compositional changes of different blackberry and raspberry cultivars after marmalade production. [ABSTRACT FROM AUTHOR]

Background. The nephroprotective effect of vitamins E and C or losartan against cisplatin (CP)- induced nephrotoxicity when they are accompanied by estrogen was investigated. Methods. The ovariectomized rats received estradiol valerate for two weeks. At the end of the first week, a single dose of CP (7 mg/kg, IP) was also administered, and they received placebo (group 1), vitamin E (group 2), vitamin C (group 3), or losartan (group 4) every day during the second week, and they were compared with another three control groups. Results. CP alone increased the serum levels of blood urea nitrogen (BUN), creatinine (Cr), and kidney tissue damage score (KTDS), significantly (P < 0.05), however at the presence of estradiol and CP, vitamin C, vitamin E, or losartan not only did not decrease these parameters, but also increased them significantly (P < 0.05). The serum level of superoxidase dismutase (SOD) was reduced by CP (P < 0.05), but it was increased when estradiol or estradiol plus vitamin C or losartan were added (P < 0.05). Conclusion. The particular pharmacological dose of estrogen used in this study abolish the nephroprotective effects vitamins C and E or losartan against CP-induced nephrotoxicity. [ABSTRACT FROM AUTHOR]

The correlation between endothelial function and reactive oxygen species detecting from diabetic microvascular wall and the antioxidant effect of ascorbic acid (AA) during early and late phases of diabetic induction were determined. Male Spraque-Dawley rats were divided into four groups: control, diabetes rats (DM, using iv.injection of 55 mg/kg BWstreptozotocin, (STZ)), and two groups of DM rats treated with AA (1 g/L, (STZ)) starting on day 2 (DM + AAday2) and week 6th (DM + AA6wk). On 12th week after STZ injection, the findings showed that in DM group, Ach (10-5 M)-induced vasodilatation was decreased, while the number of leukocyte adhesion was increased significantly (P < 0.01). Interestingly, these abnormalities induced by DM could be protected or improved in both AA-treated groups, DM + AAday2 and DM + AA6wk. By using dihydrorhodamine 123, our findings also indicated that the existing of ROS productions on diabetic arteriolar and venular walls were different significantly (ROSarteriole = 165.89 ± 24.59 and ROSvenule = 172.26 ± 34.70) (P < 0.05).Moreover by using BH4 inhibitor to induce increase in arteriolar ROS, the results also confirmed that AA could improve endothelial function with closed correlation to its potential to reduce vascular ROS content. [ABSTRACT FROM AUTHOR]

Obesity and metabolic syndrome increase the risk of cardiovascular morbidity and mortality. Oxidative stress seems to be involved in the path physiology of cardiovascular complications of metabolic syndrome. In this study we investigated the effects of vitamins A, C, and E in the management of metabolic syndrome traits condition in albino rats fed with high salt diet. The rats were placed on 8% NaCl diet for 5 weeks and then supplemented with these vitamins for additional 4 weeks in the presence of salt diet. Supplementation with vitamins significantly (P < 0.01 ) decreased blood pressure of the rats as compared with the control. Supplementation also significantly (P < 0.05) reduced serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, and very-low-density lipoprotein cholesterol and increased high-density lipoprotein cholesterol, and total antioxidant status as compared with untreated group. The percentage protection of the supplemented groups against atherogenesis indicated 55.50 ± 3.75%. Percentage weight gain indicated significant positive correlation with triglyceride, insulin resistance, and malondialdehyde while total antioxidant status and nitric oxide showed significant negative correlation. Salt diet significantly (P < 0.05) induced features of metabolic syndrome. The result, therefore, indicated strong relationship between obesity and metabolic syndrome and underscores the role of these vitamins in the management of metabolic syndrome. [ABSTRACT FROM AUTHOR]

Arabidopsis root system responds to phosphorus (P) deficiency by decreasing primary root elongation and developing abundant lateral roots. Feeding plants with ascorbic acid (ASC) stimulated primary root elongation in seedlings grown under limiting P concentration. However, at high P, ASC inhibited root growth. Seedlings of ascorbate-deficient mutant (vtc1) formed short roots irrespective of P availability. P-starved plants accumulated less ascorbate in primary root tips than those grown under high P. ASCtreatment stimulated cell divisions in root tips of seedlings grown at low P. At high P concentrations ASC decreased the number of mitotic cells in the root tips. The lateral root density in seedlings grown under P deficiency was decreased by ASC treatments. At high P, this parameter was not affected by ASC-supplementation. vtc1 mutant exhibited increased lateral root formation on either, P-deficient or P-sufficient medium. Irrespective of P availability, high ASC concentrations reduced density and growth of root hairs. These results suggest that ascorbate may participate in the regulation of primary root elongation at different phosphate availability via its effect on mitotic activity in the root tips. [ABSTRACT FROM AUTHOR]

Previously, we have reported that ascorbic acid regulates calcium signaling in human larynx carcinoma HEp-2 cells. To evaluate the precise mechanism of Ca2+ release by ascorbic acid, the effects of specific inhibitors of the electron transport chain components on mitochondrial reactive oxygen species (ROS) production and Ca2+ mobilization in HEp-2 cells were investigated. It was revealed that the mitochondrial complex III inhibitor (antimycin A) amplifies ascorbate-induced Ca2+ release fromintracellular stores. The mitochondrial complex I inhibitor (rotenone) decreases Ca2+ release from intracellular stores in HEp-2 cells caused by ascorbic acid and antimycin A. In the presence of rotenone, antimycin A stimulates ROS production by mitochondria. Ascorbate-induced Ca2+ release in HEp-2 cells is shown to be unaffected by catalase. The results obtained suggest that Ca2+ release in HEp-2 cells caused by ascorbic acid is associated with induced mitochondrial ROS production. The data obtained are in line with the concept of redox signaling that explains oxidant action by compartmentalization of ROS production and oxidant targets. [ABSTRACT FROM AUTHOR]

Introduction. Nutritional deficiencies are rarely reported in developed countries. We report a child of Pakistani origin brought up in Dubai who developed skeletal manifestations of scurvy due to peculiar dietary habits. Case Presentation. A 4.5 year old boy presented with pain and swelling of multiple joints for three months and inability to walk for two months. Dietary history was significant for exclusive meat intake for the preceding two years. On examination the child's height and weight were below the 5th percentile for his age. He was pale and tachycardic. There was significant swelling and tenderness over the wrist, knee and ankle joints, along with painful restriction of motion. Basic blood workup was unremarkable except for anemia. However, X-rays showed delayed bone age, severe osteopenia of the long bones, epiphyseal separation, cortical thinning and dense zone of provisional calcification, suggesting a radiological diagnosis of scurvy. The child was started on vitamin C replacement therapy. Over the following two months, the pain and swelling substantially reduced and the child became able to walk. Repeat X-rays showed improvement in the bony abnormalities. Conclusion. Although scurvy is not a very commonly encountered entity in the modern era, inappropriate dietary intake can lead to skeletal abnormalities which may be confused with rickets. A high index of suspicion is thus required for prompt diagnosis of scurvy in patients with bone and joint symptoms. [ABSTRACT FROM AUTHOR]

Reduction of [PtCl6]2- by L-ascorbic acid (H2ASc) in 0.1M aqueous acid medium has been investigated spectrophotometrically under pseudo-first order condition at [PtCl6]2- = 0.005-0.007 mol dm-3, 0.05 ⩽ [H2ASc]/moldm-3 ⩽0.3, 298 K ⩽ T ⩽308 K, [H+] = 0.14 mol dm-3, I = 0.5moldm-3 . The redox reaction follows the rate law: d[Pt(IV)]/dt = k[H2ASc][Pt(IV)], where k is the second-order rate constant and [H2ASc] is the total concentration of ascorbic acid. Electron transfer from [H2ASc] to Pt(IV) center leading to the release of two halide ions and formation of the reaction products, square planner Pt(II) halide complex, and dehydrated ascorbic acid is suggested. This redox reaction follows an outersphere mechanism as Pt(IV) complex is substituted inert. Activation parameters were calculated corresponding to rate of electron transfer reaction k. Activation parameters favor the electron transfer reaction. [ABSTRACT FROM AUTHOR]

The fabrication of galactose biosensor based on functionalised ZnO nanorods is described. The galactose biosensor was developed by immobilizing galactose oxidase on ZnO nanorods in conjunction with glutaraldehyde as a cross-linker molecule. The IRAS study provided evidence for the interaction of galactose oxidase with the surface of ZnO nanorods. The electromotive force (EMF) response of the galactose biosensor was measured by potentiometric method.We observed that the proposed biosensor has a linear detection range over a concentration range from 10 mM to 200 mM with good sensitivity of 89.10 ± 1.23 mV/decade. In addition, the proposed biosensor has shown fast time response of less than 10 s and a good selectivity towards galactose in the presence of common interferents such as ascorbic acid, uric acid, glucose, and magnesium ions. The galactose biosensor based on galactose oxidase immobilized ZnO nanorods has a shelf life more than four weeks. [ABSTRACT FROM AUTHOR]

Summary Objectives: To reduce the increase of oxidative stress and the upregulation of CD40L during stenting procedure using ascorbic acid infusion. Background: CD40L upregulation occurring after coronary Percutaneous Coronary Intervention predicts vascular events but the underlying mechanism is still unclear. Methods: Fifty-six patients undergoing elective coronary stenting were randomly allocated to intravenous infusion of the antioxidant ascorbic acid or placebo. Platelet CD40L and plasma levels of soluble CD40L and of 8-hydroxy-2′-deoxyguanosine, a marker of oxidative stress, were measured before and after coronary stenting. In vitro study was also done to measure reactive oxidant species and CD40L expression in platelets exposed to anoxia-reoxygenation. Results: Placebo-treated patients showed a significant increase of platelet CD40L, soluble CD40L and 8-hydroxy-2′-deoxyguanosine compared to baseline values. Patients given ascorbic acid showed no change of soluble CD40L and platelet CD40L but a significant decrease of 8-hydroxy-2′-deoxyguanosine. After 60 and 120 min, soluble CD40L, platelet CD40L and 8-hydroxy-2′-deoxyguanosine were significantly lower in the ascorbic acid-treated group compared to the placebo-treated one. A significant correlation between platelet CD40L and soluble CD40L and between soluble CD40L and 8-hydroxy-2′-deoxyguanosine was observed. Platelets, in vitro exposed to anoxia-reoxygenation, had a burst of ROS and an upregulation of CD40L that were inhibited by ascorbic acid or apocynin, an inhibitor of NADPH oxidase. Conclusions: This study shows that in patients undergoing coronary stenting CD40L is upregulated with a mechanism which is likely mediated by oxidative stress. [ABSTRACT FROM AUTHOR]

ABSTRACT Plums easily show internal browning (IB) after low temperature storage. Polyphenol oxidase (PPO) was recognized as the main reason for IB of many kinds of fruits. The aim of this study was to develop a vacuum infiltration-based method with ascorbic acid (AsA) to inhibit plum PPO. The results showed that browning rate and PPO activity of plum fruits ( Prunus salicina Lindell cv. Yuhuang) were significantly inhibited by vacuum infiltration with 0.5% AsA during 98 days of storage at 3 ± 1C, and its preservation effects, which included inhibition of browning and keeping fruit quality, were better than those produced by vacuum infiltration with 0.1% AsA or dipping treatment with 0.5% AsA. Based on the results, the method of browning inhibition for postharvest plum consisted of 10 min infiltration time, 200 mmHg and 0.5% AsA. PRACTICAL APPLICATIONS Postharvest plum fruits suffer chilling injury phenomenon followed by internal browning that reduces the consumer acceptance and commercial value. However, traditional preservation methods, such as dipping with antistaling agent, are limited in browning inhibition. Thus, a new and efficient method for intact plums stored at 3 ± 1C was developed to reduce the internal browning of postharvest plum fruits, increase the supply of plum fruits with high quality, and enhance the income of farmers and dealers. The application parameters of this vacuum infiltration-based method are based on: 10 min of infiltration time, a vacuity of 200 mmHg, and a concentration of 0.5% of AsA solution. [ABSTRACT FROM AUTHOR]

Summary What is known and Objective: The increased central sympathetic activity typically associated with chronic heart failure (CHF) is probably mediated by formation of reactive oxygen species (ROS) in the brain. Our objective was to undertake a trial to test our hypothesis that administration of the well-known antioxidant and ROS scavenger ascorbic acid, would reverse or reduce the sympathetic overactivity in CHF patients. Methods: In a prospective, randomized, placebo-controlled, double-blind, cross-over trial, 11 CHF patients were treated with ascorbic acid 2 g/day or placebo for 3 days. At the end of each treatment period, sympathetic nervous system activity was measured by microneurography for direct muscle sympathetic nerve activity (MSNA) recording, analysis of heart rate variability (HRV) and measurement of plasma norepinephrine concentrations. Results: During ascorbic acid administration, plasma vitamin C levels were higher than during placebo (74·9 ± 6·0 μmol/L vs. 54·8 ± 4·6 μmol/L, P = 0·03). Ascorbic acid had no effect on sympathetic activity: MSNA (ascorbic acid: 66·8 ± 3·3 vs. placebo 66·9 ± 3·2 bursts/100 beats, P = 0·98). In addition, HRV and plasma norepinephrine levels did not differ. What is new and Conclusion: Short-term administration of the antioxidant ascorbic acid in CHF patients does not reverse the increased sympathetic activity as measured by microneurography, HRV and plasma norepinephrine levels. The use of higher oral dosages seems not feasible due to accompanying side effects. [ABSTRACT FROM AUTHOR]

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ABSTRACT Various dipping pretreatments have been investigated for orange-fleshed sweet potato (OFSP) to retain carotenoids after drying and subsequent storage. Effects of blanching, sodium metabisulfite (0.5 or 1%), acids (ascorbic acid [1%] or citric acid [0.5%]) or salt (1%), either singly or as mixtures, were tested on dried OFSP chips that were stored for up to 6 months in ambient conditions. Overall, there was a positive effect of dipping on total carotenoid content after drying compared with control ( P < 0.05). A slight improvement in carotenoid content was observed during the first month of storage with ascorbic acid, sodium metabisulfite, and mixtures of sodium metabisulfite and citric acid, or ascorbic acid and salt pretreatments, but these higher levels were not maintained over longer storage periods (4-6 months). The general lack of improvement was believed to result from the leaching and degradation of the chemicals during storage. PRACTICAL APPLICATIONS Vitamin A deficiency (VAD) is a major cause of blindness among children in developing countries and some crops such as orange-fleshed sweet potato (OFSP) rich in provitamin A could help tackle VAD. Drying is a traditional preservation process of sweet potato in some developing countries where it is consumed, but the problem is that losses of carotenoids occur during drying and subsequent storage of OFSP chips. Some practical and affordable ways for processors of OFSP in developing countries to reduce these losses are needed. This manuscript provides practical information on the effect of dipping pretreatments on carotenoid losses, in particular, during storage. This information can be relevant for farmers and millers working with OFSP or other root crops. More generally, this work can inform users of the above chemical pretreatments on the effect of these on carotenoid preservation in similar dried food commodities. [ABSTRACT FROM AUTHOR]

Lab prepared Triphala ghrita was studied for its possible anticataract activity on galactose induced cataract in Swiss albino rats. Administration of Triphala ghrita at a dose of 216 mg/200 g, 1080 mg/200 g, and 2160 mg/200 g of rat orally offered significant dose dependent protection against galactose induced cataract and delayed the onset and progression of cataract. It was seen that the dose of 1080 mg of Triphala ghrita did not show stage II cataract in 14 days and stage III in 21 days. It did not show even stage III and stage IV cataract after 30 days whereas group B and group C showed stage III and stage IV cataracts. Dose of 2160 mg did not showed stage IV cataract after 30 days but showed stage III cataract. Dose of 1080 mg of Triphala ghrita offered significant protection against delaying the onset and progression of cataract in comparison to other doses. This effect may be attributed to the antioxidant activity of gallic acid, ellagic acid and ascorbic acid which shows their presence in Triphala ghrita. This preliminary study was encouraging but further studies are required to extrapolate the clinical usefulness of this formulation. [ABSTRACT FROM AUTHOR]

The effects of feeding Acipenser persicus and Huso huso larvae with Artemia nauplii enriched with ascorbyl palmitate (AP) and lipid emulsions on inducing tolerance against abrupt changes in environmental conditions (such as elevated levels of salinity, temperature, nitrite and total ammonia) were investigated. The 10 days post-hatch fish larvae were fed with decapsulated cysts (DC) or newly hatched Artemia urmiana nauplii enriched with saturated lipids and HUFA emulsions containing 0, 10, and 20% AP. The control groups received non-enriched nauplii as source of food. Each feeding experiment was carried out for 15 days in four replicates under controlled laboratory culture conditions. Ten randomly collected A. persicus and H. huso larvae from each replicate were subjected to different salinities, nitrite, total ammonia concentrations and temperatures. The results showed that feeding with Artemia nauplii enriched with HUFA and higher concentrations of vitamin C induces significantly higher tolerance to shocks in abiotic conditions in fish larvae of both species, as shown by higher survival. Nevertheless the two fish species did not exhibit a similar pattern of response: A. persicus showed higher tolerance compared to H. huso. Enrichment with HUFA alone did not result in a significantly improved tolerance, indicating the importance of dietary vitamin C to cope with abrupt physico-chemical changes. [ABSTRACT FROM AUTHOR]

This study aimed at evaluating the effects of enriching Artemia nauplii with the essential fatty acids docosahaexanoic acid (DHA) and eicosapentaenoic acid (EPA), and vitamin C (ascorbyl-6 palmitate) on growth and survival of early life history stages of Acipenser persicus and Huso huso. The fish larvae were fed with A. urmiana either in the form of decapsulated cysts, newly-hatched nauplii, or nauplii enriched with saturated lipid or highly unsaturated fatty acid (HUFA) emulsions supplemented with vitamin C, (0, 10 and 20% w/w) during a 15-days culture period. The zootechnical parameters were measured every alternate day in order to determine larval survival and growth. Larvae fed on decapsulated cysts of A. urmiana had significantly lower growth and survival compared to other treatments. Survival of larvae fed on HUFA + 20% vitamin C was significantly better than the larvae fed only with vitamin C. Maximum increase in growth parameters was observed in larvae fed Artemia nauplii enriched with HUFA + 20% vitamin C. [ABSTRACT FROM AUTHOR]

A 60-day experiment was carried out to study the effects of vitamin C [ascorbic acid (AA)] on the growth, digestive enzyme activities and intestinal microbial population. Diets with six levels (0.0, 21.4, 45.1, 69.5, 93.6 and 142.1 mg AA kg diet) of supplemental ascorbyl polyphosphate were fed to juvenile Jian carp ( Cyprinus carpio var. Jian) (12.63±0.02 g). The specific growth rate (SGR), feed efficiency and productive protein value were significantly improved with increasing AA levels up to 45.1 mg AA kg diet ( P<0.05). The hepatopancreas and muscle AA concentrations were increased with increasing dietary AA levels up to 69.5 and 45.1 mg kg diet respectively ( P<0.05). The activities of intestinal trypsin, chymotrypsin, lipase, α-amylase, Na, K-ATPase, alkaline phosphatase, gamma-glutamyl transpeptidase and creatinkinase were all positively affected by the AA supplementation ( P<0.05). Intestinal Lactobacillus and Bacillus were increased with increasing AA levels up to 45.1 mg AA kg diet ( P<0.05), while intestinal Escherichia coli decreased with increasing AA levels up to 45.1 mg AA kg diet ( P<0.05). In conclusion, AA improve the digestive capacity and intestinal microbial population of Jian carp, and the dietary AA requirement for SGR of juvenile Jian carp was 40.9 mg AA kg diet. [ABSTRACT FROM AUTHOR]

A 29-year old female presented with a one-week history of vomiting, diarrhoea, abdominal pain, and headache. On admission, she had acute renal failure requiring dialysis. Tests revealed a hemolytic anemia with thrombocytopenia. An initial diagnosis of thrombotic thrombocytopenic microangiopathy was made and plasma exchange was instigated. However, renal biopsy did not show thrombotic microangiopathy but instead revealed acute kidney injury with mild tubulointerstitial nephritis and numerous oxalate crystals, predominantly in the distal tubules. The patient had been taking large doses (>1100 mg daily) of vitamin C for many months. She also gave a history of sclerotherapy using injections of an ethylene glycol derivative for superficial leg veins. The patient completed five sessions of plasma exchange and was able to discontinue dialysis. She eventually achieved full renal recovery. She has now discontinued sclerotherapy and vitamin supplementation. [ABSTRACT FROM AUTHOR]

Although a multitude of syndromes have been thoroughly described as a result of vitamin deficiencies, over consumption of such substances may also be quite dangerous. Intratubular crystallization of calcium oxalate as a result of hyperoxaluria can cause acute renal failure. This type of renal failure is known as oxalate nephropathy. Hyperoxaluria occurs as a result of inherited enzymatic deficiencies known as primary hyperoxaluria or from exogenous sources known as secondary hyperoxaluria. Extensive literature has reported and explained the mechanism of increased absorption of oxalate in malabsorptive syndromes leading to renal injury. However, other causes of secondary hyperoxaluria may also take place either via direct dietary consumption of oxalate rich products or via other substances which may metabolize into oxalate within the body. Vitamin C is metabolized to oxalate. Oral or parenteral administration of this vitamin has been used in multiple settings such as an alternative treatment of malignancy or as an immune booster. This article presents a clinical case in which ingestion of high amounts of vitamin C lead to oxalate nephropathy. This article further reviews other previously published cases in order to illustrate and highlight the potential renal harm this vitamin poses if consumed in excessive amounts. [ABSTRACT FROM AUTHOR]

A single-step environmental friendly approach is employed to synthesize silver nanoparticles. The biomolecules found in plants induce the reduction of Ag+ ions from silver nitrate to silver nanoparticles (AgNPs). UV-visible spectrum of the aqueous medium containing silver ions demonstrated a peak at 425 nm corresponding to the plasmon absorbance of silver nanoparticles. Transmission electron microscopy (TEM) showed the formation of well-dispersed silver nanoparticles in the range of 5-20 nm. Xray diffraction (XRD) spectrum of the AgNPs exhibited 2ϑ values corresponding to the silver nanocrystal. The process of reduction is extracellular and fast which may lead to the development of easy biosynthesis of silver nanoparticles. Plants during glycolysis produce a large amount of H+ ions along with NAD which acts as a strong redoxing agent; this seems to be responsible for the formation of AgNPs. Water-soluble antioxidative agents like ascorbic acids further seem to be responsible for the reduction of AgNPs. These AgNPs produced show good antimicrobial activity against common pathogens. [ABSTRACT FROM AUTHOR]

A very sensitive electrochemical sensor constructed of a glassy carbon electrode modified with a layer-by-layer MWCNT/dopedoveroxidized polypyrrole (oppy/MWCNT /GCE) was used for the determination of acetaminophen (AC) in the presence of codeine and ascorbic acid (AA). In comparison to the bare glassy carbon electrode, a considerable shift in the peak potential together with an increase in the peak current was observed for AC on the surface of oppy/MWCNT/GCE, which can be related to the enlarged microscopic surface area of the electrode. The effect of the experimental conditions on the electrode response, such as types of counter ion, pyrrole and counter ion concentration, potential and number of cycles in the polymerization procedure, amount of MWCNT, and the pH, were investigated. Under the optimized conditions, the calibration curve was obtained over two concentration ranges of 2 × 10-7-6 × 10-6M and 4 × 10-5-1 × 10-4M of AC with a linear correlation coefficient (R2) of 0.9959 and 0.9947, respectively. The estimated detection limit (3σ) for AC was obtained as 5 × 10-8 M. The developed method was successfully applied to analyze the pharmaceutical preparations of AC, and a recovery of 95% with a relative standard deviation of 0.98% was obtained for AC. [ABSTRACT FROM AUTHOR]