Effect of vitamin D3 supplementation in winter on physical performance of university students: a one-month randomized controlled trial.

BACKGROUND: There is epidemiological evidence which suggests an association between 25-hydroxyvitamin D [25(OH)D] levels and bone and muscle function; however, it is unclear whether vitamin D supplementation has an added benefit beyond bone health. Here, we investigated the effects of vitamin D3 supplementation (1 month) on physical performance in Chinese university students in winter. METHODS: One hundred and seventeen eligible subjects with 25(OH)D (19.2 ± 7.8 ng/mL) were randomly assigned to either vitamin D3 supplement (N = 56; 1000 IU/day) or the control (N = 61) group for 1 month. Pre- and post-measurements included: 1) serum levels of 25(OH)D; 2) musculoskeletal and pulmonary function [vertical jump height (VJH) and right handgrip strength (RHS), forced vital capacity (FVC), and forced expiratory volume at 1s (FEV1)]; 3) bone turnover markers [parathyroid hormone (PTH), n-terminal osteocalcin (N-MID), and calcium]; 4) hemoglobin-related parameters [hemoglobin (Hb), hematocrit (HCT), red blood cells (RBC), and red cell distribution width (RDW)]; 5) lipid parameters [total triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C)]; 6) Fatigue-related indicators [serum creatine kinase (CK), lactate dehydrogenase (LDH), and total testosterone (T)]. In addition, aerobic capacity was assessed by measuring maximal oxygen uptake (VO2max) at baseline. RESULTS: During wintertime, supplementation with 1000 IU/d of vitamin D3 significantly increased serum 25(OH)D levels (from 18.85 ± 7.04 to 26.98 ± 5.88 ng/mL, p < 0.05), accompanied by a decrease of PTH (p < 0.05). However, vitamin D3 supplementation did not significantly impact the physical performance, serum lipid parameters, and bone turnover markers of students. Furthermore, 25(OH)D was found to be positively correlated with VJH and negatively correlated with PTH and TC at the beginning and end of the study (p < 0.05). In addition, the multiple linear regression analysis showed that 25(OH)D combined with athletic, gender, height, weight, Hb, and FVC could account for 84.0% of the VO2max value. CONCLUSIONS: The study demonstrated that one-month of 1000 IU/d of vitamin D3 supplementation during the winter had beneficial effects on 25(OH)D status and PTH. However, vitamin D3 intervention was not sufficient to improve physical performance. Furthermore, 25(OH)D levels combined with athletic, Hb and FVC could be a predictor of VO2max.

Effect of thermal treatment on the physicochemical, ultrastructural and nutritional characteristics of whole grain highland barley.

Highland barley (HB) was subjected to three thermal treatments (heat fluidization, microwave, and baking) and assessed for physicochemical, ultrastructural and nutritional properties. After thermal treatments, the hardness, bulk density, thousand kernel weight, length/breadth ratio, and color difference decreased significantly, while puffing index increased. Meanwhile, the formation of fissure was observed in the appearance. Microstructure images illustrated that numerous micropores were evenly distributed in the endosperm structure, and aleurone layer cells were deformed by compression. Furthermore, a dramatically disruption of endosperm cell walls and slightly deformation of outer layers were observed by confocal laser scanning microscopy. Moreover, a notably decrease in total phenolics (14.02%-36.91%), total flavonoids (25.28%-44.94%), and bound phenolics (8.99%-27.53%) was detected, while free phenolics (8.81%-43.40%), ß-glucan extractability (4.71%-43.66%), antioxidant activity (71.87%-349.77%), and reducing power (3.05%-56.13%) increased significantly. Greatest increase in nutritional values was caused by heat fluidization, which possessed the potential for development of ready-to-eat functional foods.

Impact of aqueous ozone mixing on microbiological, quality and physicochemical characteristics of semi-dried buckwheat noodles.

The microbiological, microstructural, and physicochemical impact of aqueous ozone mixing (AOM) on semi-dried buckwheat noodles (SBWN) was elucidated in this study. Microbiological measurements declared that AOM reduced the initial total plate count (TPC) of SBWN significantly (P < 0.05) with a prolonged shelf-life of 2 ~ 5 days. Meanwhile, AOM reduced the cooking loss and water absorption along with the enhancement of hardness and tension force. Scanning electron microscopy (SEM) showed that the protein network of surface and cross section became continuous and compact, and wrapped starch granules more effectively. Moreover, an obvious increase in the intensity of the high molecular protein bands was observed in the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) patterns. Furthermore, the sodium dodecyl sulfate extractable protein (SDSEP) under non-reducing condition obviously decreased, and then the SDSEP under reducing condition changed insignificantly (P > 0.05). These results indicated that AOM mainly promoted the protein cross-linking of SBWN by disulfide bond (SS) cross-links.

Increasing the physicochemical stability of stored green tea noodles: Analysis of the quality and chemical components.

Different methods used to process green tea powder noodles (GTPN) were compared by analyzing the quality and chemical components of the final products. Significant differences were observed in the discoloration rate, color loss, and lightness of all noodles. Polyphenol oxidase activity was effectively inhibited through the heat treatment, resulting in retardation of the GTPN discoloration rate. However, heat-exposed GTPN showed a higher surface lightness due to a greater loss of chlorophyll. The chlorophyll contents of GTPN prepared with a new method (a combination of water treatment and heat exposure) were prominently higher than those prepared by heat treatment alone, and exhibited less color loss. The heat-exposed noodles had relatively low free polyphenol contents, and their textural properties were not significantly decreased after 28 d. Therefore, combining water treatment and heat exposure in the preparation process has great potential for increasing the stability of GTPN.

Rheological and quality characteristics of composite gluten-free dough and biscuits supplemented with fermented and unfermented Agaricus bisporus polysaccharide flour.

In this study, functional, rheological and physicochemical characteristics were carried out for composite gluten-free (CGF) flours, dough and biscuits, respectively fortified with fermented and unfermented Agaricus bisporus polysaccharide (FABP and UABP) flours. Addition of both FABP flour and UABP flour improved functional properties, while addition of FABP flour decreased viscosity property. Incorporation of both polysaccharide flours in CGF biscuit dough revealed a significant increase in rheological moduli (G' and G″) and a decrease in tan (δ). Supplementation of UABP flour increased thickness, whereas supplementation of FABP flour increased diameter and spread ratio. All CGF biscuit formulations exhibited lower fracture strength and hardness compared to the control. Furthermore, both UABP flour and FABP flour formulation (F3) contained the highest nutrients in terms of protein, dietary fibers, amino acids and minerals among the CGF biscuit formulations. The sensory evaluation result showed that FABP flour formulation (F1) and UABP flour F1 were most acceptable.

The enhanced inhibition of water extract of black tea under baking treatment on α-amylase and α-glucosidase.

This paper studied the inhibition of water extract of natural or baked black tea on the activity of α-amylase and α- glucosidase. Baking treatment was found to be one effective way to enhance the inhibition of black tea on both α-amylase and α- glucosidase, and IC50 of water extract of baked black tea (BBTWE) were 1.213mg/mL and 4.190mg/mL, respectively, while IC50 of water extract of black tea (BTWE) were 1.723mg/mL and 6.056mg/mL, respectively. This study further studied the mechanism of the effect of water extract on α-amylase and α- glucosidase using HPLC, circular dichroism, and synchronous fluorescence. HPLC analysis of tea polyphenols showed that the content of tea polyphenols with low polarity increased after baking. In addition, BBTWE had higer abilty on decreasing the hydrophobicity of tryptophan residues than BTWE for both α-amylase and α- glucosidase.The increase of α-helix proportion of α-amylase when treated with BBTWE was more obvious than that when treated with BTWE. In a word, thermal process of baked foods may be beneficial for tea polyphenols to reduce the rate of starch digestion.

Shelf-life extension of semi-dried buckwheat noodles by the combination of aqueous ozone treatment and modified atmosphere packaging.

The present study investigated the combined effects of aqueous ozone treatment and modified atmosphere packaging (MAP) on prolonging the shelf-life of semi-dried buckwheat noodles [SBWN; moisture content (22.5±0.5%)] at 25°C. Firstly, the different concentrations of ozonated water were used to make SBWN. Subsequently, SBWN prepared with ozonated water were packaged under six different conditions and stored for 11days. Changes in microbial, chemical-physical, textural properties and sensorial qualities of SWBN were monitored during storage. Microbiological results indicated that adopting 2.21mg/L of ozonated water resulted in a 1.8 log10 CFU/g reduction of the initial microbial loads in SBWN. In addition, MAP suppressed the microbial growth with a concomitant reduction in the rates of acidification and quality deteriorations of SBWN. Finally, the shelf-life of sample packed under N2:CO2=30:70 was extended to 9days, meanwhile textural and sensorial characteristics were maintained during the whole storage period.