Developing a Scale Using Item Response Theory of the Self-Resilience in Taekwondo Players.

The purpose of this study was to identify the ego-resiliency of Taekwondo athletes and to develop a scale measuring such skills. We collected preliminary data using an open-ended online survey targeting Taekwondo athletes from nine countries (South Korea, China, Malaysia, United States, Spain, France, Brazil, United Kingdom, and Taiwan) who participated in international competitions between 2019 and 2020. We extracted participants' ego-resiliency from 48 survey responses, guided by expert meetings and a thorough literature review. We verified our Taekwondo ego-resiliency scale's construct validity using 741 survey responses. We utilized V coefficients, parallel analysis, an exploratory structural equation model, maximum likelihood, confirmatory factor analysis, and multi-group confirmatory factor analysis for data analysis. We identified four core ego-resiliency types: "empathy," "coach support," "care," and "parent support/effort". Our final measure, which demonstrated evidence of reliability and validity, comprises 18 items spanning 4 factors, with each item rated on a 3-point Likert scale.

Facile preparation of water soluble curcuminoids extracted from turmeric (Curcuma longa L.) powder by using steviol glucosides.

Curcuminoids from rhizomes of Curcuma longa possess various biological activities. However, low aqueous solubility and consequent poor bioavailability of curcuminoids are major limitations to their use. In this study, curcuminoids extracted from turmeric powder using stevioside (Ste), rebaudioside A (RebA), or steviol glucosides (SG) were solubilized in water. The optimum extraction condition by Ste, RebA, or SG resulted in 11.3, 9.7, or 6.7mg/ml water soluble curcuminoids. Curcuminoids solubilized in water showed 80% stability at pH from 6.0 to 10.0 after 1week of storage at 25°C. The particle sizes of curcuminoids prepared with Ste, RebA, and SG were 110.8, 95.7, and 32.7nm, respectively. The water soluble turmeric extracts prepared with Ste, RebA, and SG showed the 2,2-diphenyl-1-picrylhydrazyl radical scavenging (SC50) activities of 127.6, 105.4, and 109.8µg/ml, and the inhibition activities (IC50) against NS2B-NS3(pro) from dengue virus type IV of 14.1, 24.0 and 15.3µg/ml, respectively.

One-step isolation of sappanol and brazilin from Caesalpinia sappan and their effects on oxidative stress-induced retinal death.

Caesalpinia sappan is a well-distributed plant that is cultivated in Southeast Asia, Africa, and the Americas. C. sappan has been used in Asian folk medicine and its extract has been shown to have pharmacological effects. Two homoisoflavonoids, sappanol and brazilin, were isolated from C. sappan by using centrifugal partition chromatography (CPC), and tested for protective effects against retinal cell death. The isolated homoisoflavonoids produced approximately 20-fold inhibition of N-retinylidene-N-retinyl-ethanolamine (A2E) photooxidation in a dose-dependent manner. Of the 2 compounds, brazilin showed better inhibition (197.93 ± 1.59 µM of IC50). Cell viability tests and PI/Hoechst 33342 double staining method indicated that compared to the negative control, sappanol significantly attenuated H2O2-induced retinal death. The compounds significantly blunted the up-regulation of intracellular reactive oxygen species (ROS), and sappanol inhibited lipid peroxidation in a concentration-dependent manner. Thus, both compounds represent potential antioxidant treatments for retinal diseases.

Characterization of core-shell calcium-alginate macrocapsules fabricated by electro-coextrusion.

Spherical macrocapsules, where calcium-alginate shell enclosed olive oil as a model core medium, were fabricated by electro-coextrusion. The effects of three key process factors, including alginate concentration in shell fluid (0.5-4.0%), shell-to-core flow rate ratio (4-12 at a fixed core flow rate of 0.05 mL/min), and applied voltage (0-10 kV), on the morphological and textural characteristics of the macrocapsules were analyzed using response surface methodology. The analysis showed that the diameter, shell thickness, hardness, and breaking energy of the macrocapsules were in the ranges of 0.89-1.61 mm, 17.4-66.4 µm, 1.37-11.01 N, and 0.34-6.90 mJ, respectively, and strongly influenced by all the three factors, except that the surface appearance was only significantly affected by the shell-to-core flow rate ratio. The process factors were also optimized for the practically useful macrocapsules, having non-oily surface and hardness larger than 3 N, using a graphical optimization technique.

Effects of heating, aerial exposure and illumination on stability of fucoxanthin in canola oil.

The effects of heating, aerial exposure and illumination on the stability of fucoxanthin was investigated in canola oil. In the absence of air and light, the heating caused the degradation of total and all-trans fucoxanthin at all tested temperatures between 25 and 100 °C. The increase of heating temperature promoted the formation of 13-cis and 13'-cis and the degradation of 9'-cis. The degradation and formation reactions were found to follow simple first-order kinetics and to be energetically unfavorable, non-spontaneous processes. Arrhenius-type temperature dependence was observed for the degradation of total and all-trans fucoxanthin but not for the reactions of cis isomers. The aerial exposure promoted the oxidative fucoxanthin degradation at 25 °C, whilst illumination caused the initial formation of all-trans, with concurrent sudden degradation of 13-cis and 13'-cis, and the considerable formation of 9'-cis. The fucoxanthin degradation was synergistically promoted when exposed to both air and light.

Tyrosinase inhibition by water and ethanol extracts of a far eastern sea cucumber, Stichopus japonicus.

BACKGROUND: Tyrosinase plays a key role in hyperpigmentaion and enzymatic browning. The present study was aimed at investigating the inhibitory effects of water and 70% aqueous ethanol extracts of Stichopus japonicus, a sea cucumber long consumed as a tonic food and traditional medicine, on the diphenolase activity of tyrosinase. RESULTS: In the tyrosinase inhibition study, high-performance liquid chromatography completely separated L-3,4-dihydroxyphenylalanine and dopachrome from other compounds present in the extracts, and provided more reliable results than the commonly used spectrophotometry. The ethanol extract (IC(50)=0.49-0.61 mg mL(-1)) showed higher inhibitory activity than the water extract (IC(50)=1.80-1.99 mg mL(-1)). Enzyme inhibition by the extracts was reversible and of mixed type. For both extracts, the dissociation constants for binding to free enzyme were significantly smaller than those for binding to enzyme-substrate complex. Ethyl-α-D-glucopyranoside (IC(50)=0.19 mg mL(-1)), isolated for the first time from sea cucumber, and adenosine (IC(50)=0.13 mg mL(-1)), were identified as key tyrosinase inhibitors. CONCLUSION: The sea cucumber extracts were demonstrated to possess considerable inhibitory potency against the diphenolase activity of tyrosinase, suggesting that the sea cucumber may be a good source of safe and effective tyrosinase inhibitors.

Characteristics and antioxidant activity of catechin-loaded calcium pectinate gel beads prepared by internal gelation.

Catechin-loaded calcium pectinate gel beads prepared by internal gelation were characterized for their catechin entrapment efficiency and release behavior. The entrapment efficiency was higher when the beads were prepared with a lower catechin-to-pectin ratio, shorter gelling time, higher pectin concentration, and lower acetic acid concentration. The entrapment efficiency was much higher under all tested conditions, when the beads were prepared by internal gelation instead of external gelation. The catechin release was slower for the beads prepared with lower catechin-to-pectin ratio, longer gelling time, and higher concentrations of pectin and acetic acid in both simulated gastric and intestinal fluids. Antioxidant power of catechin was effectively maintained in alkaline simulated intestinal fluid when catechin was entrapped within the beads, compared to cases where it was not entrapped, indicating that the beads can protect catechin molecules from the alkaline environment and release them in a sustained fashion.

Optimization of calcium pectinate gel beads for sustained-release of catechin using response surface methodology.

Response surface methodology was used to optimize bead preparation conditions, including CaCl(2) concentration (X(1)), hydroxypropylmethylcellulose concentration (X(2)), and bead-hardening time (X(3)), for the sustained-release of catechin from the calcium pectinate gel beads reinforced with liposomes and hydroxypropylmethylcellulose into simulated gastric fluid (SGF) and intestinal fluid (SIF). The optimized values of X(1), X(2), and X(3) were found to be 5.82%, 0.08%, and 10.29min, respectively. The beads prepared according to the optimized conditions released only about half of the entrapped catechin into SGF while most of the entrapped catechin was released into SIF after 24h incubation.

Preparation and characterization of calcium pectinate gel beads entrapping catechin-loaded liposomes.

Calcium pectinate gel (CPG) beads entrapping catechin-loaded liposomes were prepared with or without hydroxypropylmethylcellulose (HPMC) (denoted as CPG-LH and CPG-L beads, respectively) and characterized in comparison with the CPG beads prepared without liposome and HPMC (denoted as CPG-C beads). For all types of beads, the catechin entrapment efficiency decreased by about 40-50% as the concentration of CaCl2 in gelling media increased from 2 to 6%. At a constant CaCl2 level, the entrapment efficiency was higher in the order of CPG-LH, CPG-L, and CPG-C beads. The in vitro release test showed that in simulated intestinal fluid the rate of catechin release was higher in the order of CPG-C, CPG-L, and CPG-LH beads, indicating that the catechin release was slowed by liposome and further retarded when HPMC was used simultaneously, whereas not in simulated gastric fluid. The addition of cholesterol in liposome could not retard but accelerated the catechin release. The results suggest that the CPG beads reinforced with liposome and HPMC could be employed for a sustained oral delivery of catechins, although further improvements are necessary.