Ascorbic Acid Intake Research Articles

Comparative Effectiveness of Ascorbic Acid vs. Calcium Ascorbate Ingestion on Pharmacokinetic Profiles and Immune Biomarkers in Healthy Adults: A Preliminary Study.

Previous trials have displayed augmented intracellular vitamin C concentrations in the leukocytes at 24 h after acute supplementation with 1000 mg calcium ascorbate (CA), compared to ascorbic acid (AA). The primary objective was to evaluate comparative leukocyte vitamin C accumulation kinetics over 32 h following acute 250 mg or 500 mg doses from the two sources. Secondary objectives were to evaluate neutrophil phagocytic function and lymphocyte differentiation between the two sources of vitamin C. Ninety-three healthy females (250 mg, n = 27; 500 mg, n = 24) and males (250 mg, n = 19; 500 mg, n = 23) were assigned to ingest a single dose of CA or AA providing 250 mg or 500 mg of vitamin C in two separate double-blind, randomized crossover trials. There were no significant differences in the primary or secondary outcomes between the two treatments in the 250 mg low-dose study. Conversely, there was evidence that ingestion of 500 mg of CA increased DHA in plasma, increased neutrophil functionality during the first 8 h of the PK study, promoted increased natural killer cells, and altered weight-adjusted PK profiles, suggesting greater volume distribution and clearance from the blood. These findings indicate that 500 mg of CA may promote some immune benefits compared to 500 mg of AA ingestion.

Higher serum ascorbic acid levels are associated with lower depression prevalence in US adults: a case-control study.

Recent studies have shown that a higher intake of ascorbic acid was associated with a lower prevalence of depression. Nevertheless, the recall bias was common in dietary surveys in these studies, and it was ignored that there were differences in the absorption and utilization of ascorbic acid in the body. Hence, we aim to investigate the association between serum ascorbic acid levels and the prevalence of depression in US adults. A total of 3,404 participants from the 2017-2018 National Health and Nutrition Examination Survey (NHANES) that underwent measurement of the Patient Health Questionnaire-9 (PHQ-9) scores and serum levels of ascorbic acid. Propensity Score Matching (PSM) successfully established a case-control study, comprising 299 participants diagnosed with depression and 1,107 as controls. We used binary logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) to explore associated risk factors for depression. Restricted cubic splines (RCS) were used to show the nonlinear relationship between serum ascorbic acid levels and the prevalence of depression. The prevalence of depression was approximately 8.8%, with a median serum ascorbic acid level of 49.9 (36.0, 67.0) μmol/L. Results revealed that the serum ascorbic acid levels of depressed patients were significantly lower than those of non-depressed individuals (42.97 VS 52.97 μmol/L). The baseline data indicated that as serum ascorbic acid levels increased from Quartile 1 (Q1) to Quartile 4 (Q4), the depression prevalence decreased from 12.0 to 5.4% (p < 0.05). The results of the chi-square test after PSM showed that serum ascorbic acid was still statistically significant (p < 0.001) with the prevalence of depression. Forest plot showed that compared with the Q1 of serum ascorbic acid level, the OR and 95%CI of depression prevalence in Q4 was 0.42 (0.30 ~ 0.61), and the adjusted OR and 95%CI of depressive prevalence was 0.49 (0.33 ~ 0.73). RCS models showed an L-shaped nonlinear relationship (P for nonlinearity <0.05) between serum ascorbic acid and depression. Our results suggested that higher serum ascorbic acid levels are associated with a reduced prevalence of depression.

Nutritional status of flexitarians compared to vegans and omnivores - a cross-sectional pilot study

BackgroundIn the Western world, there has been a notable rise in the popularity of plant-based, meat-reduced flexitarian diets. Nevertheless, there is insufficient data on the nutritional status of individuals following this dietary pattern. The aim of this study was to investigate the intake and endogenous status of various nutrients in a healthy German adult study population consisting of flexitarians (FXs), vegans (Vs) and omnivores (OMNs).MethodsIn this cross-sectional study, dietary intake of 94 non-smoking adults (32 FXs, 33 Vs, 29 OMNs) between 25 and 45 years of age was assessed using 3-day dietary records. In addition, blood samples were collected to determine different endogenous nutrient status markers.Results32%, 82% and 24% of the FXs, Vs, and OMNs respectively reported using dietary supplements. In the FXs, intake of total energy as well as macronutrients and most micronutrients were within the reference range. FXs had higher intakes of fiber, retinol-equ., ascorbic acid, folate-equ., tocopherol-equ., calcium, and magnesium compared to OMNs. However, cobalamin intake in FXs (2.12 µg/d) was below the reference (4 µg/d). Based on 4cB12, 13% of FXs showed a cobalamin undersupply [< -0.5 to -2.5] compared to 10% of OMNs, and 9% of Vs. The median 25(OH)D serum concentrations in FXs, Vs and OMNs were 46.6, 55.6, and 59.6 nmol/L. The prevalence of an insufficient/deficient vitamin-D status [< 49.9 nmol 25(OH)D/L] was highest in FXs (53%), followed by Vs (34%) and OMNs (27%). In FXs and Vs, the supplement takers had better cobalamin and vitamin-D status than non-supplement takers. Anemia and depleted iron stores were found only occasionally in all groups. In women, the prevalence of pre-latent iron deficiency and iron deficiency was highest in FXs (67%) compared to Vs (61%) and OMNs (54%).ConclusionOur findings indicated that all three diets delivered sufficient amounts of most macro- and micronutrients. However, deficiencies in cobalamin, vitamin-D, and iron status were common across all diets. Further studies are needed to investigate the nutrient supply status and health consequences of meat-reduced plant-based diets. The study was registered in the German Clinical Trial Register (number: DRKS 00019887, data: 08.01.2020).

Effects of Daily Ingestion of Two SunGold Kiwifruit for 6 Weeks on Metabolic and Inflammatory Biomarkers: A Randomized, Cross-Over, Exploratory Intervention Study.

Kiwifruit contain many components, some considered beneficial, such as vitamins, phytochemicals and dietary fibre, and others potentially harmful, such as fructose and glucose in fruit sugars. In a 6-week, randomised, crossover study aimed at exploring the net effects of daily consumption of kiwifruit, 23 healthy participants consumed two Actinidia chinensis var. chinensis 'Zesy002' (marketed as Zespri™ SunGold™ Kiwifruit) per day as part of their customary diet (intervention) or without kiwifruit (control) as their customary diet for 6 weeks in a cross-over study. Anthropometric data, venous blood, and urine samples were collected at the start and end of the 6-week intervention and control periods for the measurement of physical changes, plasma glucose, insulin, glycated haemoglobin, short-chain fatty acids, blood lipids, uric acid, inflammatory biomarkers, and urinary ascorbic acid. Variables were measured between the start and finish of interventions, and between intervention and control periods. Food diaries were completed on the 3 days before blood sampling to estimate dietary ascorbic acid and dietary fibre intakes. Despite urinary vitamin C and food diaries indicating compliance, and good precision in measurements, there were no appreciable changes in biomarkers during the study, either within or between intervention and control periods, that would indicate a change in health status. Thus, the sizes of any effects of kiwifruit ingestion were too small to become significant under the test conditions used, indicating a high probability that daily ingestion of two SunGold kiwifruit is safe with respect to metabolic health.

Substrate and fertigation management modulate microgreens production, quality and resource efficiency

Long-term space missions will require a self-sustaining food production system to meet the crew’s nutritional and health needs. For this purpose, plant-based food production systems with elevated resource efficiency are required, based on advanced agricultural technologies that produce phytonutrient-rich crops. In addition to the resource requirements for crop production on Earth, volume and time efficiency become essential factors to consider for food production in space. Microgreens represent a promising candidate for space farming as they have a high harvest index, short cultivation cycle, and high nutritional potential. However, the development of specific technical protocols for growing microgreens in space is essential since different agronomic inputs, such as substrates and fertigation, can modulate productivity, quality and resource efficiency of microgreens cultivation. The current work examines the effects of different substrates (coconut fiber and cellulose sponge) and nutrient solution (NS) management strategies (quarter strength Hoagland and half strength Hoagland/osmotic water) on the production of two species of microgreens [Raphanus sativus cv. Saxa 2 (Radish); Brassica oleracea var. capitata f. sabauda cv. Vertus (Savoy cabbage)]. The appraisal focused on (i) biomass production and quality, and (ii) sizing of space facilities devoted to the production of phytonutrients required for the astronauts’ wellbeing. In our study, the interaction among species, substrate and NS significantly affected the accumulation of fructose, sucrose, total soluble non-structural carbohydrates and nitrate as well as the daily production of total ascorbic acid and, in turn, the required microgreens serving to supply its adequate daily intake. Species-substrate interaction effects on fresh yield, dry yield, dry matter, anthocyanins, TPC, β-carotene and sulfate content as well as the cultivation surface required to produce the adequate daily intake of ascorbic acid (AscA) were assessed. Substrate-NS interaction modulated the anthocyanins, violaxanthin and sulfate contents independently of species. On the other hand, single factor effects were identified with respect to the accumulation of lutein, chlorophylls, glucose, and starch. Therefore, the management of microgreens cultivation in terms of NS and substrate is an effective tool to meet the phytochemical requirements of the crew.

Inhibitory Effect of Ascorbic Acid on Glutathione S-transferase from Human Erythrocytes

Background: Inhibition of certain specific glutathione S-transferase isozymes is associated with the efficacy of chemotherapy in the treatment of cancer patients. Objective: We aimed to determine whether ascorbic acid, which can be used as a drug and antioxidant food supplement, is a glutathione S-transferase isozyme inhibitor. Methods: For this purpose, glutathione S-transferase was first purified from human erythrocytes and the in vitro effect of ascorbic acid on enzyme activity was investigated. Then, kinetic studies were performed to evaluate the inhibition potential of ascorbic acid, which was determined to be an inhibitor of the enzyme. Results: The enzyme was purified 1286-fold with a yield of 81% and specific activity of 18.00 U/mg protein. The effects of ascorbic acid were tested on the in vitro enzyme activity of glutathione Stransferase and detected to be an inhibitor for the enzyme with 10 mM of IC50 value. Ki constants and inhibition type were also determined for the enzyme. Conclusion: This finding indicates that ascorbic acid can be an effective inhibitor of some GST isozymes increased in cancer cells. Abundant ascorbic acid intake may prevent cancer formation by strengthening the antioxidant defense system, on the other hand, it may increase the effectiveness of cancer treatment by inhibiting the chemotherapy-resistant GST enzyme.

Response Surface Optimization for the Enhancement of the Extraction of Bioactive Compounds from Citrus limon Peel.

Citrus limon is among the species of the genus Citrus that dominates the world market. It is highly nutritious for humans as it contains twice the amount of the suggested daily intake of ascorbic acid and is also a good source of phenolic compounds, carotenoids, and other bioactive compounds. This study aimed to identify the optimal extraction procedures and parameters to obtain the maximum quantity of bioactive components from lemon peel by-products. Various extraction techniques, including stirring, ultrasound, and pulsed electric field, were evaluated, along with factors such as extraction time, temperature, and solvent composition. The results revealed that simple stirring for 150 min at 20 °C proved to be the most effective and practical method. The ideal solvent mixture consisted of 75% ethanol and 25% water, highlighting the crucial role of solvent composition in maximizing extraction efficiency. Among the extracted compounds were phenolics, ascorbic acid, and carotenoids. Under optimum extraction conditions, the extract was found to contain high total phenolic content (TPC) (51.2 mg of gallic acid equivalents, GAE/g dry weight), total flavonoid content (TFC) (7.1 mg of rutin equivalents, RtE/g dry weight), amounts of ascorbic acid (3.7 mg/g dry weight), and total carotenoids content (TCC) (64.9 μg of β-carotene equivalents, CtE/g). Notably, the extracts demonstrated potent antioxidant properties (128.9 μmol of ascorbic acid equivalents, AAE/g; and 30.3 μmol of AAE/g as evidenced by FRAP and DPPH assays, respectively), making it a promising ingredient for functional foods and cosmetics. The study's implications lie in promoting sustainable practices by converting lemon peel into valuable resources and supporting human health and wellness through the consumption of natural antioxidants.

Association of Women Leading Land Use with Energy and Nutrient Intakes Among Children Aged 6 to 59 Months in Oromia, Ethiopia

Nutrition-specific interventions alone will not help countries to end child malnutrition; nutrition-sensitive interventions such as women empowerment are also needed. Therefore, this cross sectional study was conducted to assess the association of women leading land use with nutrient intakes among children aged 6 to 59 months in Oromia, Ethiopia. Three hundred thirty-two caregivers participated in the study. A pretested questionnaire was used to collect data on background characteristics of child caregivers, women leading land use status, and caregivers’ exposure to mass media. Dietary assessment for nutrients intake was collected using a 24-hour recall. The survey data was analyzed using SPSS software version 25. Descriptive statistics were presented in frequency and percentages and in the form of mean ± SD. The nutrient intakes were compared with recommended dietary allowances to analyze the gap between the intakes and the recommendations were presented as percentages. Any difference in the variables was compared, based on women leading land use, using Chi square test and Mann Whitney u test, depending on the type of data. Results were considered statistically significant at P<0.05. Starchy staples were consumed by more than 90% of the children; close to ¾ of the children consumed legumes and nuts; animal source foods consumption was below 20% except dairy products (84%). Vitamin A rich fruits and vegetables were consumed by 33% of the children on average; and the minimum dietary diversity score was achieved by 48% of the children. The median energy intakes for children aged above a year and calcium intakes during the second half of the first year were more than 90%. On the other hand, the intakes of energy, at the stage of the second 6 months, fat, the calcium (>1 year) and the ascorbic acid intake were below 90%. Intake of Fat and Ascorbic acid was very low. Interestingly, iron intake for the children of 6-12 months age was more than 100%. However, there was statistical difference (p<0.05) in the proportion children of women with land leading power and without land leading power who consumed starchy staples, legumes and nuts, dairy products as well as ascorbic acid. Women empowerment in deciding land use issues affect about their child feeding practices and ultimately nutritional outcome and therefore, Women empowerment should be ensured for better child feeding practices and nutrients intake.

Nutrition, Genital Tract Infection, Hematologic Values, and Premature Rupture of Membranes Among African American Women

Using a prospective comparative design, African American gravidae with and without genital tract infection were assessed with respect to dietary intakes, serum nutrient values, hematologic values, and pregnancy outcomes. Intakes of ascorbic acid, vitamin A, protein, and iron were the dietary variables while levels of ascorbic acid, protein, albumin, globulin, and ferritin were the variables measured in serum. The hematologic variables included hemoglobin, hematocrit, and red and white blood cell counts. Pregnancy outcome was defined on the basis of premature rupture of the membranes (PROM), and infant birth weight, birth length, gestational age, and head circumference. The sample consisted of 335 nulliparous women who were between 16-35 years of age, 96 of whom had genital tract infection based on laboratory reports. Findings indicated no significant differences between the mean dietary intakes as well as serum values of the infected and non-infected women, and no difference in the incidence of PROM. However, non-infected women had a better mean hematologic profile than the infected gravidae during pregnancy. Also, for the non-infected group, there were significant relationships between head circumference and protein consumption (P = .015) and serum ferritin (P = .05). For the infected women, the relationship between the hemoglobin and hematocrit measurements obtained at the first prenatal visit and infant birth weight, birth length and head circumference were statistically significant.

Long-Term Low Ascorbic Acid Intake Reduces Bone Mass in Guinea Pigs

The effect of long-term (1 y) low to excess ascorbic acid (AA) intake on bone mass was evaluated using guinea pigs that were 12–14 d old at the start of the experiment. Dietary AA was low (0.15 g/kg diet) (n = 7), normal (0.50 g/kg) (n = 8) or excess (10 g/kg) (n = 8). After 12 mo, total body bone mineral density (BMD, mg/cm2) and bone mineral content (BMC, g) were determined by dual energy X-ray absorptiometry. Histomorphometric analysis of the cancellous bone of the proximal tibial metaphysis was completed after in vivo dual fluorochrome labeling. Total body BMD of the low AA group was 4.9% lower (P < 0.05), and total body BMC was 12.4% lower (P < 0.05) than in the normal AA group. Total body BMD and BMC were similar in normal and excess AA groups and in the low and excess AA groups. Histomorphometric analysis indicated significantly greater (P < 0.05) double-labeled bone surface, mineralizing surface, and bone formation rate in the low AA guinea pigs compared with the normal AA animals. Thus, there was greater bone turnover in the low AA group than in the normal AA guinea pigs. No differences in histomorphometric endpoints existed between the normal AA and excess AA groups. Long-term AA deficiency, during the period of rapid growth and slower phases of skeletal maturation, resulted in bone abnormalities in adult guinea pig skeletons. Long-term dietary AA excess caused no such abnormalities.

Low Ascorbic Acid Intake Induces Inflammatory Changes in Intestine and Liver of ODS Rats.

We previously demonstrated that ascorbic acid (AsA) deficiency, caused by an AsA-free diet, induces inflammatory changes in the liver and intestine of osteogenic disorder Shionogi (ODS) rats that cannot synthesize AsA. However, whether low AsA intake induces inflammatory changes remains unknown. Here, we assessed the inflammatory changes in ODS rats caused by low AsA intake and compared them to ODS rats that were fed a diet supplemented with sufficient amounts of AsA (300 mg/kg). Male ODS rats (12-wk-old) were fed an AsA-free diet (0 ppm group), AsA 20 mg/kg diet (20 ppm group), AsA 40 mg/kg diet (40 ppm group) or AsA 300 mg/kg diet (300 ppm group) for 22 d. The hepatic mRNA levels of acute phase proteins, including C-reactive protein (CRP) and haptoglobin, were higher in the 0 and 20 ppm groups, than in the 300 and 40 ppm groups, but were not significantly higher in the 20 ppm group. Serum CRP concentrations were significantly higher in the 0 and 20 ppm groups than in the 300 and 40 ppm groups. Jejunal and ileal interleukin-1β (IL-1β) mRNA levels were higher in the 0 and 20 ppm groups than in the 300 ppm group. Jejunal and ileal IL-6 mRNA levels tended to be higher in the 0 and 20 ppm groups than in the 300 ppm group. Furthermore, the portal IL-6 concentration gradually increased with decrease in the AsA intake. Thus, inflammatory changes could occur in both AsA-deficient ODS rats and ODS rats with low AsA intake.

A NUTRITIONAL STUDY OF TRIBAL AND NON-TRIBAL CHILDREN IN THE UDAIPUR REGION

Objective: There is an evidence that nutrition has a significant impact on children’s development, adult health, and senescence. It is also known to have an impact on one’s physical and mental faculties. Malnutrition is now understood to be the root cause of a significant variety of health issues. To compare the nutritional condition of 300 (tribal and nontribal) children living in the Udaipur region, a dietary survey was conducted. Methods: In the present study, 300 tribal and non-tribal children between the ages of 1 and 12 were chosen for a dietary survey to evaluate their nutritional status. The survey was conducted using a questionnaire. Results and Conclusion: The statistics between tribal and non-tribal children showed that calorie, protein, fat, and carbohydrate intake was lower in the tribal children. When we compared the data between tribal and non-tribal children, we found that the non-tribal children’s calorie, protein, fat, and carbohydrate intake was not superior. Ascorbic acid and B-carotene intake among non-tribals is also less than that advised by the ICMR and is approximately twice as low as that among their tribal counterparts. The statistics on tribal and non-tribal children made it abundantly evident that nutritional intake is low that consumption of fat among dense nutrients is significantly lower and that intake of antioxidant nutrients such as ascorbic acid and beta-carotene is similarly poor.

A Portable Sweat Sensor Based on Carbon Quantum Dots for Multiplex Detection of Cardiovascular Health Biomarkers.

The future of personalized diagnostics and treatment of cardiovascular diseases lies in the use of portable sensors. Portable sensors can acquire biomarker information in biological fluids such as sweat, an approach that mitigates the shortcomings of conventional hospital-centered healthcare. Low sensitivity, selectivity, and specificity remain bottlenecks for the widespread use of portable sensors. Herein, we demonstrate a portable sensor that simultaneously detects Na+, ascorbic acid, and human neuropeptide Y in sweat, all useful biomarkers to index cardiovascular health. The portable sensor comprises a six-electrode system containing three working electrodes, two reference electrodes, and one counter electrode. The working electrodes were prepared by depositing sensing components on carbon quantum dot (CQD) electrodes. The sensing mechanisms were based on selective ion recognition, enzyme catalytic reaction, and immune response, which guarantees specificity to corresponding targets. The CQDs offer massive reactive sites and effectively reduce the interfacial impedance during the sensing reaction, thereby enhancing the three biomarkers' detection sensitivity. As evidence of portable sensor capability, we demonstrate herein its effective simultaneous detection of the three biomarkers in a real sweat from healthy volunteers during routine activities including exercise, extra ascorbic acid ingestion, and extra Na+ ingestion. As such, the sensor shows promise for real-time noninvasive personalized medical diagnostics and metabolic wellness management.

Metabolism and Regulation of Ascorbic Acid in Fruits.

Ascorbic acid, also known as vitamin C, is a vital antioxidant widely found in plants. Plant fruits are rich in ascorbic acid and are the primary source of human intake of ascorbic acid. Ascorbic acid affects fruit ripening and stress resistance and plays an essential regulatory role in fruit development and postharvest storage. The ascorbic acid metabolic pathway in plants has been extensively studied. Ascorbic acid accumulation in fruits can be effectively regulated by genetic engineering technology. The accumulation of ascorbic acid in fruits is regulated by transcription factors, protein interactions, phytohormones, and environmental factors, but the research on the regulatory mechanism is still relatively weak. This paper systematically reviews the regulation mechanism of ascorbic acid metabolism in fruits in recent decades. It provides a rich theoretical basis for an in-depth study of the critical role of ascorbic acid in fruits and the cultivation of fruits rich in ascorbic acid.

Undetectable triglycerides related to the combined intake of ascorbic acid and tacrolimus.

Management of triglyceride (TG) levels is essential in intensive care units (ICU), especially to manage the risk of pancreatitis induced by propofol. However, some therapeutics in ICU such as intravenous ascorbic acid protocol, especially used in the context of Covid-19 could lead to false decrease of triglycerides by analytical disruption of Trinder reaction. We report here the case of a sample with unmeasurable triglyceride levels partly due to high plasma ascorbic acid levels. However, repeated measure on the same sample four days later revealed that interference mechanism on TG was still present whereas the level of ascorbic acid was very reduced by oxidation degradation. Hence, additional interference mechanism was suspected. After clinical investigation, we found that the patient had also received high doses of tacrolimus due to a transplant. As previous studies reported that tacrolimus treatment lead to a decrease of the measured plasma activity of lipoprotein lipase (LPL), we hypothesized that tacrolimus or related metabolites could also interfere by direct inhibition of LPL involved in TG analytical method used.

Ascorbic acid intake is inversely associated with prevalence of depressive symptoms in US midlife women: A cross-sectional study

BackgroundWith the endocrine changes in menopausal transition period, associations between dietary ascorbic acid intake and depressive symptoms may be different. This investigation examined cross-sectional relations between dietary ascorbic acid intake of women and prevalence of depressive symptoms. MethodsThis is a secondary analysis performed on a subsample of the Study of Women's Health Across the Nation (SWAN). Women enrolled had measures of CES-D depression scores and ascorbic acid intake. Regression models were used to study cross-sectional associations between ascorbic acid intake and depressive symptoms. ResultsA total of 3088 women aged 42–52 years at baseline were included in the present study. Dietary ascorbic acid intake was inversely associated with depressive symptoms. The adjusted OR and 95% CI of depressive symptoms was 0.699 (0.524 – 0.934) in quartile 4 (the highest) versus quartile 1 (the lowest) of the ascorbic acid intake. Restricted cubic spline analyze showed a suggestion of L-shaped associations between ascorbic acid intake and depressive symptoms. ConclusionsAscorbic acid intake is inversely associated with prevalence of depressive symptoms in midlife women. Future prospective cohort studies are needed to confirm these findings.

Ascorbic Acid Content and Transcriptional Profiling of Genes Involved in Its Metabolism during Development of Petals, Leaves, and Fruits of Orange (Citrus sinensis cv. Valencia Late).

Citrus fruit is one of the most important contributors to the ascorbic acid (AsA) intake in humans. Here, we report a comparative analysis of AsA content and transcriptional changes of genes related to its metabolism during development of petals, leaves and fruits of Valencia Late oranges (Citrus sinensis). Petals of close flowers and at anthesis contained the highest concentration of AsA. In fruits, AsA content in the flavedo reached a maximum at color break, whereas the pulp accumulated lower levels and experienced minor fluctuations during development. AsA levels in leaves were similar to those in the flavedo at breaker stage. The transcriptional profiling of AsA biosynthetic, degradation, and recycling genes revealed a complex and specific interplay of the different pathways for each tissue. The D-galacturonic acid pathway appeared to be relevant in petals, whereas in leaves the L-galactose pathway (GGP and GME) also contributed to AsA accumulation. In the flavedo, AsA content was positively correlated with the expression of GGP of the L-galactose pathway and negatively with DHAR1 gene of the recycling pathway. In the pulp, AsA appeared to be mainly controlled by the coordination among the D-galacturonic acid pathway and the MIOX and GalDH genes. Analysis of the promoters of AsA metabolism genes revealed a number of cis-acting elements related to developmental signals, but their functionalities remain to be investigated.

Dietary Antioxidant Capacity and Serum Inflammatory Biomarkers Levels in Cancer Survivors

This study aimed to compare the dietary intake of carotenoids, tocopherols, ascorbic acid, flavonoids, and dietary total antioxidant capacity (dTAC) and to evaluate relationship of dTAC with serum inflammatory biomarkers in patients with gastrointestinal system (GIS) and non-GIS cancer. In total, 104 adult cancer survivors (52 GIS and 52 non-GIS cancer cases) were included. 24-hour dietary recalls were obtained and dTAC was calculated on the basis of oxygen radical absorption capacity (ORAC), Trolox equivalent antioxidant capacity (TEAC), total radical-trapping antioxidant parameter (TRAP), ferric reducing antioxidant potential (FRAP), and vitamin C equivalents (VCE). Serum C-reactive protein (CRP) level, neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR) were used as inflammatory biomarkers. Routinely analyzed serum CRP, neutrophil, lymphocyte, and platelet levels every day in hospital biochemistry laboratory were obtained from patients’ file. There was no significant difference between patients with GIS and non-GIS cancer in terms of dietary intake of carotenoids, tocopherols, and flavonoids. While there was no significant difference between groups in terms of the mean dietary ORAC, TEAC, and FRAP, the mean TRAP of patients with GIS cancer was significantly higher than patients with non-GIS cancer. Serum inflammatory markers (CRP and NLR) were found to have an inverse relationship with dTAC.

Dietary glutamic acid and aspartic acid as biomarkers for predicting diabetic retinopathy

The screening rate of diabetic retinopathy (DR) is low despite the importance of early diagnosis. We investigated the predictive value of dietary glutamic acid and aspartic acid for diagnosis of DR using the Korea National Diabetes Program cohort study. The 2067 patients with type 2 diabetes without DR were included. The baseline intakes of energy, glutamic acid and aspartic acid were assessed using a 3-day food records. The risk of DR incidence based on intake of glutamic acid and aspartic acid was analyzed. The DR group was older, and had higher HbA1c, longer DM duration, lower education level and income than non-DR group (all p < 0.05). The intake of total energy, glutamic acid and aspartic acid were lower in DR group than non-DR group (p = 0.010, p = 0.025 and p = 0.042, respectively). There was no difference in the risk of developing DR according to the intake of glutamic acid and ascorbic acid. But, aspartic acid intake had a negative correlation with PDR. Hence, the intake of glutamic acid and aspartic acid did not affect in DR incidence. However, lower aspartic acid intake affected the PDR incidence.

Evidence of a Positive Link between Consumption and Supplementation of Ascorbic Acid and Bone Mineral Density

In animal models it has been shown that ascorbic acid (AA) is an essential cofactor for the hydroxylation of proline in collagen synthesis. However, there are still no precise indications regarding the role of AA in maintaining bone health in humans, so the aim of this narrative review was to consider state of the art on correlation between bone mineral density (BMD), AA dietary intake and AA blood levels, and on the effectiveness of AA supplement in humans. This review included 25 eligible studies. Fifteen studies evaluated correlations between AA intake and BMD: eight studies demonstrated a positive correlation between AA dietary intake and BMD in 9664 menopausal women and one significant interaction between effects of AA intake and hormone therapy. These data were also confirmed starting from adolescence (14,566 subjects). Considering studies on AA blood concentration and BMD, there are four (337 patients) that confirm a positive correlation. Regarding studies on supplementation, there were six (2671 subjects), of which one was carried out with AA supplementation exclusively in 994 postmenopausal women with a daily average dose of 745 mg (average period: 12.4 years). BMD values were found to be approximately 3% higher in women who took supplements.