Correction: Ahn et al. Enzyme-Treated Zizania latifolia Ethanol Extract Improves Liver-Related Outcomes and Fatigability. Foods 2024, 13, 1725.

In the original publication [...].

Sequential Cascade Doping of Conjugated-Polymer-Wrapped Carbon Nanotubes for Highly Electrically Conductive Platforms.

To explore a highly conductive flexible platform, this study develops PIDF-BT@SWCNT by wrapping single-walled carbon nanotubes (SWCNTs) with a conjugated polymer, PIDF-BT, known for its effective doping properties. By evaluating the doping behaviors of various dopants on PIDF-BT, appropriate dopant combinations for cascade doping are selected to improve the doping efficiency of PIDF-BT@SWCNT. Specifically, using F4TCNQ or F6TCNNQ as the first dopant, followed by AuCl3 as the second dopant, demonstrates remarkable doping efficiency, surpassing that of the individual dopants and yielding an exceptional electrical conductivity exceeding 6000 S/cm. Characterization using X-ray photoelectron spectroscopy and Raman spectroscopy elucidates the doping mechanism, revealing an increase in the proportion of electron-donating atoms and the ratio of quinoid structures upon F4TCNQ/AuCl3 cascade doping. These findings offer insights into optimizing dopant combinations for cascade doping, showcasing its advantages in enhancing doping efficiency and resulting electrical conductivity compared with single dopant processes.

Exploring Pore Formation and Gas Sensing Kinetics Using Conjugated Polymer-Small Molecule Blends.

Controlling miscibility between mixture components helps induce spontaneous phase separation into distinct domain sizes, thereby resulting in porous conjugated polymer (CP) films with different pore sizes after selective removal of auxiliary components. The miscibility of the CP mixture can be tailored by blending auxiliary model components designed by reflecting the difference in solubility parameters with the CP. The pore size increases as the difference in solubility parameters between the matrix CP and auxiliary component increases. Electrical properties are not critically damaged even after forming pores in the CP; however, excessive pore formation enables pores to spread to the vicinity of the dielectric layer of CP-based field-effect transistors (FETs), leading to partial loss of the carrier-transporting active channel in the FET. The porous structure is advantageous for not only increasing detection sensitivity but also improving the detection speed when porous CP films are applied to FET-based gas sensors for NO2 detection. The quantitative analysis of the response-recovery trend of the FET sensor using the Langmuir isotherm suggests that the response speed can be improved by more than 2.5 times with a 50-fold increase in NO2 sensitivity compared with pristine CP, which has no pores.

Enzyme-Treated Zizania latifolia Ethanol Extract Improves Liver-Related Outcomes and Fatigability.

Long-term hepatic damage is associated with human morbidity and mortality owing to numerous pathogenic factors. A variety of studies have focused on improving liver health using natural products and herbal medicines. We aimed to investigate the effect of enzyme-treated Zizania latifolia ethanol extract (ETZL), which increases the content of tricin via enzymatic hydrolysis, for 8 weeks on liver-related outcomes, lipid metabolism, antioxidant activity, and fatigue compared to a placebo. Healthy Korean adult males aged 19-60 years were randomized into ETZL treatment and placebo groups, and alcohol consumption was 24.96 and 28.64 units/week, respectively. Alanine transaminase, a blood marker associated with liver cell injury, significantly decreased after 8 weeks compared to the baseline in the ETZL treatment group (p = 0.004). After 8 weeks, the treatment group showed significant changes in the levels of high-density lipoprotein and hepatic steatosis index compared to the baseline (p = 0.028 and p = 0.004, respectively). ETZL treatment tended to reduce antioxidant-activity-related factors, total antioxidant status, and malondialdehyde, but there was no significant difference. In the multidimensional fatigue scale, ETZL treatment showed a significant reduction in general fatigue and total-fatigue-related values after 8 weeks compared to the baseline (p = 0.012 and p = 0.032, respectively). Taken together, the 8-week treatment of enzyme-treated Zizania latifolia ethanol extract demonstrated positive effects on liver-related outcomes, lipid metabolism, and mental fatigue without adverse effects on safety-related parameters.

Novel Potential Therapeutic Targets in Autosomal Dominant Polycystic Kidney Disease from the Perspective of Cell Polarity and Fibrosis.

Autosomal dominant polycystic kidney disease (ADPKD), a congenital genetic disorder, is a notable contributor to the prevalence of chronic kidney disease worldwide. Despite the absence of a complete cure, ongoing research aims for early diagnosis and treatment. Although agents such as tolvaptan and mTOR inhibitors have been utilized, their effectiveness in managing the disease during its initial phase has certain limitations. This review aimed to explore new targets for the early diagnosis and treatment of ADPKD, considering ongoing developments. We particularly focus on cell polarity, which is a key factor that influences the process and pace of cyst formation. In addition, we aimed to identify agents or treatments that can prevent or impede the progression of renal fibrosis, ultimately slowing its trajectory toward end-stage renal disease. Recent advances in slowing ADPKD progression have been examined, and potential therapeutic approaches targeting multiple pathways have been introduced. This comprehensive review discusses innovative strategies to address the challenges of ADPKD and provides valuable insights into potential avenues for its prevention and treatment.

Antibiofilm and antithrombotic hydrogel coating based on superhydrophilic zwitterionic carboxymethyl chitosan for blood-contacting devices.

Blood-contacting devices must be designed to minimize the risk of bloodstream-associated infections, thrombosis, and intimal lesions caused by surface friction. However, achieving effective prevention of both bloodstream-associated infections and thrombosis poses a challenge due to the conflicting nature of antibacterial and antithrombotic activities, specifically regarding electrostatic interactions. This study introduced a novel biocompatible hydrogel of sodium alginate and zwitterionic carboxymethyl chitosan (ZW@CMC) with antibacterial and antithrombotic activities for use in catheters. The ZW@CMC hydrogel demonstrates a superhydrophilic surface and good hygroscopic properties, which facilitate the formation of a stable hydration layer with low friction. The zwitterionic-functionalized CMC incorporates an additional negative sulfone group and increased negative charge density in the carboxyl group. This augmentation enhances electrostatic repulsion and facilitates the formation of hydration layer. This leads to exceptional prevention of blood clotting factor adhesion and inhibition of biofilm formation. Subsequently, the ZW@CMC hydrogel exhibited biocompatibility with tests of in vitro cytotoxicity, hemolysis, and catheter friction. Furthermore, in vivo tests of antithrombotic and systemic inflammation models with catheterization indicated that ZW@CMC has significant advantages for practical applications in cardiovascular-related and sepsis treatment. This study opens a new avenue for the development of chitosan-based multifunctional hydrogel for applications in blood-contacting devices.

Characteristics and Absorption Rate of Whey Protein Hydrolysates Prepared Using Flavourzyme after Treatment with Alcalase and Protamex.

The purpose of this study was to evaluate the physicochemical properties of whey protein hydrolysate and determine changes in absorption rate due to enzymatic hydrolysis. The molecular weight distribution analysis of whey protein concentrate (WPC) and low-molecule whey protein hydrolysate (LMWPH) using the Superdex G-75 column revealed that LMWPH is composed of peptides smaller than those in WPC. Fourier-transform infrared spectroscopy indicated differences in peak positions between WPC and LMWPH, suggesting hydrolysis-mediated changes in secondary structures. Moreover, LMWPH exhibited higher thermal stability and faster intestinal permeation than WPC. Additionally, oral LMWPH administration increased serum protein content at 20 min, whereas WPC gradually increased serum protein content after 40 min. Although the total amount of WPC and LMWPH absorption was similar, LMWPH absorption rate was higher. Collectively, LMWPH, a hydrolysate of WPC, has distinct physicochemical properties and enhanced absorptive characteristics. Taken together, LMWPH is composed of low-molecular-weight peptides with low antigenicity and has improved absorption compared to WPC. Therefore, LMWPH can be used as a protein source with high bioavailability in the development of functional materials.

Yeast Hydrolysate Inhibits Lipid Accumulation via Regulation of Lipid Accumulation-Related Genes in a Drosophila Model of High-Sugar Diet-Induced Obesity.

The increasing frequency of processed food consumption has led to the higher ingestion of sugar, increasing the risk of chronic diseases, such as obesity. Yeast hydrolysates (YHs) inhibit body fat accumulation. However, the action mechanism of YH in relation to high-sugar diet-induced obesity is still unclear. Therefore, this study aimed to evaluate the biological effects of YH on lipid accumulation and verify behavioral changes and carbohydrate metabolic gene regulation in high-sugar diet-fed fruit flies. Adult male flies (Drosophila melanogaster; 2-5 days old) were exposed to 20% sucrose for obesity induction. In high-sugar-fed Drosophila, the effect of YH was compared with that of yeast extract. The effects of YH on body conditions and lipid droplet size were quantified and analyzed. Behavioral factors were evaluated by analyzing circadian rhythm patterns and neurotransmitter content, and a molecular approach was used to analyze the expression of metabolism-related genes. Dietary supplementation with YH did not reduce total sugar content, but significantly decreased the triglyceride (TG) levels in Drosophila. A behavioral analysis showed that the total number of night-time activities increased significantly with YH treatment in a dose-dependent manner. In addition, YH effectively regulated the gene expression of insulin-like peptides related to carbohydrate metabolism as well as genes related to lipogenesis. The TG content was significantly reduced at a YH concentration of 0.5%, confirming that the active compound in YH effectively suppresses fat accumulation. These findings support that YH is a potential anti-obesity food material via regulating carbohydrate metabolism in Drosophila.

Combination of Cysteine and Glutathione Prevents Ethanol-Induced Hangover and Liver Damage by Modulation of Nrf2 Signaling in HepG2 Cells and Mice.

Excessive alcohol consumption increases oxidative stress, leading to alcoholic liver disease. In this study, the protective effects of a mixture of cysteine and glutathione against ethanol-induced hangover and liver damage were evaluated in mice and HepG2 cells. Ethanol (2 mL/kg) was orally administered to the mice 30 min before receiving the test compounds (200 mg/kg), and the behavioral and oxidative stress-related biochemical parameters altered by ethanol were analyzed. Acute ethanol administration increased anxiety behavior and decreased balance coordination in mice (p < 0.001); however, a mixture of cysteine and glutathione (MIX) in a 3:1 ratio improved alcohol-induced behavior more effectively than the individual compounds (p < 0.001). The MIX group showed higher ethanol-metabolizing enzyme activity than the control group (p < 0.001) and significantly suppressed the elevation of serum alcohol (p < 0.01) and acetaldehyde (p < 0.001) levels after 1 h of ethanol administration. In HepG2 cells, 2.5 mM MIX accelerated ethanol metabolism and reduced cytochrome P450 2E1 mRNA expression (p < 0.001). MIX also increased the expression of antioxidant enzymes through the upregulation of nuclear erythroid 2-related factor 2 (Nrf2) signaling and consequently suppressed the overproduction of reactive oxygen species and malondialdehyde (p < 0.001). Collectively, MIX alleviates the hangover symptoms and attenuates the alcohol-induced oxidative stress by regulating the Nrf2 pathway.

Effects of Dendropanax morbiferus Leaf Extract on Sleep Parameters in Invertebrate and Vertebrate Models.

Dendropanax morbiferus is highly valued in traditional medicine and has been used to alleviate the symptoms of numerous diseases owing to its excellent antioxidant activity. This study aimed to evaluate the sleep promotion and related signaling pathways of D. morbiferus extract (DE) via behavioral analysis, molecular biological techniques, and electrophysiological measurements in invertebrate and vertebrate models. In Drosophila, the group treated with 4% DE experienced decreased subjective nighttime movement and sleep bout and increased total sleeping time. Moreover, substantial changes in locomotor activity, including distance moved, velocity, and movement, were confirmed in the 4% DE-treated group. Compared to Drosophila in which insomnia and oxidative stress were induced by exposure to 0.1% caffeine, the DE-treated group improved sleep-related parameters to the level of the normal group. In the Drosophila model, exposure to 4% DE upregulated the expression of gamma-aminobutyric acid (GABA)-related receptors and serotonin receptor (5-HT1A), along with the expression of antioxidant-related factors, glutathione, and catalase. In the pentobarbital-induced sleep test using ICR mice, the duration of sleep was markedly increased by high concentration of DE. In addition, through the electroencephalography analysis of SD-rats, a significant increase in non-rapid-eye-movement sleep and delta waves was confirmed with high concentrations of DE administration. The increase in sleep time and improvement in sleep quality were confirmed to be related to the expression of altered GABA receptors and the enhancement of the contents of the neurotransmitters GABA and serotonin (5-HT) because of high DE administration. High-dose administration of DE also increased the expression of antioxidant-related factors in the brain and significantly decreased malondialdehyde content. Taken together, DE induced improvements in sleep quantity and quality by regulating neurotransmitter content and related receptor expression, along with high antioxidant activity, and may have a therapeutic effect on sleep disorders.

Sleep-Enhancing Effect of Water Extract from Jujube (Zizyphus jujuba Mill.) Seeds Fermented by Lactobacillus brevis L32.

Although Ziziphus jujuba Mill (jujube) is used in folk medicine for hypnotic sedative, anxiolytic, and many other purposes, to date, only a few studies have revealed its sleep-promoting effects and related mechanisms. Currently, drugs used for the treatment of sleep disorders have various side effects, so it is essential to develop safe natural materials. Therefore, we evaluated the sleep-enhancing activity and mechanism of action of an aqueous extract of jujube seeds (ZW) fermented with Lactobacillus brevis L-32 in rodent models. The starch contained in ZW was removed by enzymatic degradation and fermented with L. brevis to obtain a fermented product (ZW-FM) with a high γ-aminobutyric acid (GABA) content. To evaluate the sleep-promoting effect of ZW-FM, pentobarbital-induced sleep tests were performed on ICR mice, and electroencephalography analysis was undertaken in Sprague Dawley rats. Additionally, the awakening relief effects of ZW-FM were confirmed in a caffeine-induced insomnia model. Finally, the mechanism of sleep enhancement by ZW-FM was analyzed using GABA receptor type A (GABAA) antagonists. The ZW-FM-treated groups (100 and 150 mg/kg) showed increased sleep time, especially the δ-wave time during non-rapid eye movement (NREM) sleep. In addition, the 150 mg/kg ZW-FM treatment group showed decreased sleep latency and increased sleep time in the insomnia model. In particular, NREM sleep time was increased and REM sleep time, which was increased by caffeine treatment, was decreased by ZW-FM treatment. ZW-FM-induced sleep increase was inhibited by the GABAA receptor antagonists picrotoxin, bicuculline, and flumazenil, confirming that the increase was the result of a GABAergic mechanism. These results strongly suggest that the increased GABA in water extract from jujube seeds fermented by L. brevis acts as a sleep-promoting compound and that the sleep-promoting activity is related to GABAA receptor binding.

Modulation of gut microbiota ecosystem by a glucan-rich snail mucin heteropolysaccharide attenuates loperamide-induced constipation.

The present study aimed to investigate the effect of oral administration of snail-derived mucin extract (SM) on ameliorating constipation symptoms of loperamide-induced constipated rats (n = 6). The analytical results indicated that SM mainly contains a glucan-rich snail mucin heteropolysaccharide with high molecular weights (108.5-267.9 kDa), comprising primarily of glucose (64.9 %) and galactose (22.4 %) with some deoxyhexoses (5.0 %) and hexosamines (4.9 %). Daily SM administration at doses of 10-40 mg/kg/day to the loperamide-induced constipated rats significantly (p < 0.05) ameliorated the deterioration in fecal parameters, such as numbers and weight of feces, fecal water contents, and gastrointestinal transit ratio. The histomorphometric results showed that the loperamide-induced decreases in the thickness of mucosal and muscularis mucosae layers as well as the distribution of mucin and c-KIT-positive areas were significantly (p < 0.05) improved via SM consumption at all doses tested. SM administration at all doses significantly increased the expression of genes encoding tryptophan hydroxylases (TPH1 and TPH2; p < 0.05), tight junction molecules (OCLN, CLDN1, and TJP1; p < 0.05), and mucin (MUC2 and MUC4; p < 0.05), but significantly decreased the aquaporin-encoding genes (AQP3 and AQP8; p < 0.05). Gut microbial community analysis indicated that SM administration could modulate loperamide-induced dysbiosis by increasing the phyla Actinobacteria (11.72-12.64 % at 10-40 mg/kg doses; p < 0.05) and Firmicutes (79.33 % and 74.24 % at 20 and 40 mg/kg doses; p < 0.05) and decreasing the phyla Bacteroidetes (5.98-12.47 % at 10-40 mg/kg doses; p < 0.05) and Verrucomicrobia (2.21 % and 2.78 % at 20 and 40 mg/kg doses; p < 0.05), suggesting that SM administration is effective in ameliorating constipation by controlling gut microbial communities. These findings can be utilized as fundamental data for developing novel functional materials using SM to prevent or treat constipation.

Preparation of Hypoallergenic Whey Protein Hydrolysate by a Mixture of Alcalase and Prozyme and Evaluation of Its Digestibility and Immunoregulatory Properties.

Whey protein (WP) has nutritional value, but the presence of ß-lactoglobulin (ß-LG) and α-lactalbumin (α-LA) cause allergic reactions. In this study, hypoallergenic whey protein hydrolyate (HWPH) was prepared by decomposing ß-LG and α-LA of WP using exo- and endo-type proteases. The enzyme mixing ratio and reaction conditions were optimized using response surface methodology (RSM). Degradation of α-LA and ß-LG was confirmed through gel electrophoresis, and digestion, and absorption rate, and immunostimulatory response were measured using in vitro and in vivo systems. Through RSM analysis, the optimal hydrolysis conditions for degradation of α-LA and ß-LG included a 1:1 mixture of Alcalase and Prozyme reacted for 10 h at a 1.0% enzyme concentration relative to substrate. The molecular weight of HWPH was <5 kDa, and leucine was the prominent free amino acid. Both in vitro and in vivo tests showed that digestibility and intestinal permeability were higher in HWPH than in WP. In BALB/c mice, as compared to WP, HWPH reduced allergic reactions by inducing elevated Type 1/Type 2 helper T cell ratio in the blood, splenocytes, and small intestine. Thus, HWPH may be utilized in a variety of low allergenicity products intended for infants, adults, and the elderly.

Sleep-promoting activity of amylase-treated Ashwagandha (Withania somnifera L. Dunal) root extract via GABA receptors.

Ashwagandha (Withania somnifera L. Dunal), an Indian medicinal plant that has been used for centuries to treat insomnia, exhibits a variety of biological activities, such as improving cognitive function, immunity and anxiety. In this study, the effect of enzyme-treated Ashwagandha root extract (EA) and on sleep was evaluated using rodent models. Starch contained in the Ashwagandha root extract was removed by amylase treatment to prepare EA. To evaluate the sleep-promoting activity of EA, a pentobarbital-induced sleep test and electroencephalogram analysis were performed. In addition, the sleep-promoting mechanism of EA was elucidated by analyzing the expression of sleep-related receptors. In the pentobarbital-induced sleep test, EA dose-dependently increased sleep duration. Additionally, electroencephalogram analysis revealed that EA significantly increased δ-wave and non-rapid eye movement sleep times, which are involved in deep sleep, thereby improving sleep quality and quantity. EA also effectively relieved caffeine-induced insomnia symptoms. Furthermore, the γ-aminobutyric acid (GABA) content in the brain and mRNA and protein expression of GABAA, GABAB1, and serotonin receptors were significantly increased by EA compared to the normal group. In particular, EA showed sleep-promoting activity by binding to various GABAA receptor sites. Collectively, EA exhibited sleep-promoting activity through the GABAergic system and may be used as a functional material to improve sleep deprivation.

Heukharang lettuce (Lactuca sativa L.) leaf extract displays sleep-promoting effects through GABAA receptor.

ETHNOPHARMACOLOGICAL RELEVANCE: Although lettuce is traditionally known to have hypnotic and sedative effects, to date, only a few studies have documented its sleep-promoting effects and elucidated the related mechanisms. AIM OF THE STUDY: We aimed to investigate the sleep-promoting activity of Heukharang lettuce leaf extract (HLE) with increased lactucin content, known as a sleep-promoting substance in lettuce, in animal models. MATERIALS AND METHODS: To evaluate the effect of HLE on sleep behavior, analysis of electroencephalogram (EEG), gene expression of brain receptors, and activation mechanisms using antagonists were investigated in rodent models. RESULTS: High-performance liquid chromatography analysis showed that HLE contained lactucin (0.78 mg/g of extract) and quercetin-3-glucuronide (1.3 mg/g of extract). In the pentobarbital-induced sleep model, the group administered 150 mg/kg of HLE showed a 47.3% increase in sleep duration time as compared to the normal group (NOR). The EEG analysis showed that the HLE significantly increased non-rapid eye movement (NREM), where delta waves were improved by 59.5% when compared to the NOR, resulting in increased sleep time. In the caffeine-induced arousal model, HLE significantly decreased the awake time increased by caffeine administration (35.5%) and showed a similar level to NOR. In addition, HLE increased the gene and protein expression of gamma-aminobutyric acid receptor type A (GABAA), GABA type B, and 5-hydroxytryptamine (serotonin) receptor 1A. In particular, in comparison to the NOR, the group administered 150 mg/kg HLE showed an increase in expression levels of GABAA and protein by 2.3 and 2.5 times, respectively. When the expression levels were checked using GABAA receptor antagonists, HLE showed similar levels to NOR, as the sleep duration was reduced by flumazenil (45.1%), a benzodiazepine antagonist. CONCLUSIONS: HLE increased NREM sleep and significantly improved sleep behavior due to its action on the GABAA receptors. The collective findings suggest that HLE can be used as a novel sleep-enhancing agent in the pharmaceutical and food industries.

Oral Administration of Mixed Probiotics Improves Photoaging by Modulating the Cecal Microbiome and MAPK Pathway in UVB-Irradiated Hairless Mice.

SCOPE: Continuous ultraviolet (UV) exposure causes skin photoaging, wrinkle formation, and skin barrier damage. In this study, the protective effect of mixed probiotics (MP) against photoaging in UVB-irradiated Hs68 fibroblasts and SKH-1 hairless mice is investigated. METHODS AND RESULTS: The mice are irradiated with UVB for 8 weeks to induce photoaging, and MP (15 and 50 mg day-1 ) is orally administered once a day. Skin parameters are measured in the dorsal skin and wrinkle formation factors are analyzed in skin replicas. To evaluate the mitogen-activated protein kinase (MAPK) signaling pathway, western blotting and qRT-PCR are performed. MP (50 mg day-1 ) significantly improves skin moisture, transepidermal water loss, erythema, and skin thickness. MP also effectively suppresses wrinkle formation by regulating the transcriptional expression of matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs. MP also reduces inflammatory cytokine levels and phosphorylation of extracellular signaling regulatory kinase, Jun N-terminal kinase, and p38 protein. Furthermore, the intestinal microbiome of the MP groups is significantly different compared with that of the UVB group, and the relative abundance of Lactobacillus and Akkermansia is significantly increased. CONCLUSION: Collectively, these findings suggest that MP modulates the gut microbiome and ameliorates UVB-induced photoaging by downregulating the MAPK pathway.

Side-Chain-Assisted Transition of Conjugated Polymers from a Semiconductor to Conductor and Comparison of Their NO2 Sensing Characteristics.

To investigate the effect of a side chain on the electrical properties of a conjugated polymer (CP), we designed two different CPs containing alkyl and ethylene glycol (EG) derivatives as side chains on the same conjugated backbone with an electron donor-acceptor (D-A) type chain configuration. PTQ-T with an alkyl side chain showed typical p-type semiconducting properties, whereas PTQ-TEG with an EG-based side chain exhibited electrically conductive behavior. Both CPs generated radical species owing to their strong D-A type conjugated structure; however, the spin density was much greater in PTQ-TEG. X-ray photoelectron spectroscopy analysis revealed that the O atoms of the EG-based side chains in PTQ-TEG were intercalated with the conjugated backbone and increased the carrier density. Upon application to a field-effect transistor sensor for PTQ-T and resistive sensor for PTQ-TEG, PTQ-TEG exhibited a better NO2 detection capability with faster signal recovery characteristics than PTQ-T. Compared with the relatively rigid alkyl side chains of PTQ-T, the flexible EG-based side chains in PTQ-TEG have a higher potential to enlarge the free volume as well as improve NO2-affinity, which promotes the diffusion of NO2 in and out of the PTQ-TEG film, and ultimately resulting in better NO2 detection capabilities.

The Preparation and Physiochemical Characterization of Tenebrio molitor Chitin Using Alcalase.

Chitin is mostly produced from crustaceans, but it is difficult to supply raw materials due to marine pollution, and the commonly used chemical chitin extraction method is not environmentally friendly. Therefore, this study aims to establish a chitin extraction process using enzymes and to develop edible insect-derived chitin as an eco-friendly new material. The response surface methodology (RSM) was used to determine the optimal conditions for enzymatic hydrolysis. The optimal conditions for enzymatic hydrolysis by RSM were determined to be the substrate concentration (7.5%), enzyme concentration (80 µL/g), and reaction time (24 h). The solubility and DDA of the mealworm chitosan were 45% and 37%, respectively, and those of the commercial chitosan were 61% and 57%, respectively. In regard to the thermodynamic properties, the exothermic peak of mealworm chitin was similar to that of commercial chitin. In the FT-IR spectrum, a band was observed in mealworm chitin corresponding to the C=O of the NHCOCH3 group at 1645 cm-1, but this band showed low-intensity C=O in the mealworm chitosan due to deacetylation. Collectively, mealworm chitosan shows almost similar physical and chemical properties to commercial chitosan. Therefore, it is shown that an eco-friendly process can be introduced into chitosan production by using enzyme-extracted mealworms for chitin/chitosan production.

Chemical compositions and sleep-promoting activities of hop (Humulus lupulus L.) varieties.

Among natural products with sleep-promoting activity, hops have been used since ancient times as a tranquilizer and hypnotic agent. This study investigated the sleep-promoting effects of extracts of various hop (Humulus lupulus L.) varieties in invertebrate and vertebrate models. The content of α-acids, ß-acids, and xanthohumol was higher in hop 70% alcohol extracts than in hop hot water extracts. Among the alcohol extracts, Citra contained a high α-acid content (229.32 µg/mg), while Saphir showed high ß-acid and xanthohumol content (66.37 and 4.23 µg/mg, respectively). In Drosophila melanogaster, Simcoe and Mosaic water extracts and Saphir and Simcoe alcohol extracts significantly increased total nighttime sleep. Total sleep time of mice with pentobarbital-induced sleep was significantly increased by Simcoe and Mosaic water extracts and Saphir and Simcoe ethanol extracts compared to the normal group. Oral administration of Simcoe water extract and Saphir alcohol extract improved sleep in the caffeine-induced insomnia model and upregulated the mRNA expression of GABAA (gamma 2 subunit) and GABAB receptors in mouse brains. Additionally, Saphir alcohol extract significantly increased the GABA content in mouse brains. Simcoe water extract and Saphir ethanol extract modulated GABAergic signaling to improve sleep-related behaviors, including sleep duration.

Effects of gypenoside L-containing Gynostemma pentaphyllum extract on fatigue and physical performance: A double-blind, placebo-controlled, randomized trial.

This study was conducted to investigate the effect of Gynostemma pentaphyllum extract containing gypenoside L (GPE) on improving the cognitive aspects of fatigue and performance of the motor system. One hundred healthy Korean adults aged 19-60 years were randomized to the treatment (GPE for 12 weeks) and control groups, and efficacy and safety-related parameters were compared between the two groups. Maximal oxygen consumption (VO2 max) and O2 pulse were significantly higher in the treatment group than in the control group (p = 0.007 and p = 0.047, respectively). After 12 weeks, the treatment group showed significant changes such as decreases in the levels of free fatty acids (p = 0.042). In addition, there were significant differences in the rating of perceived exertion (RPE) (p < 0.05) and value of temporal fatigue between the treatment and control groups on the multidimensional fatigue scale (p < 0.05). Moreover, the level of endothelial nitric oxide synthase (eNOS) in the blood was significantly higher in the treatment group than in the control group (p = 0.047). In summary, oral administration of GPE has a positive effect on resistance to exercise-induced physical and mental fatigue.