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37 result(s) for "Boo, Kyung-Hwan"
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Immature Citrus unshiu fruit extracts inhibit adipogenesis in 3T3-L1 adipocytes via AMPK and MAPK signaling pathways
In Korea, immature citrus fruits have been extensively explored for their potential utility as functional bio-health materials owing to their various bioactive properties. However, the specific mechanisms by which they exert inhibitory effects on adipogenesis remain unclear. Therefore, this study aimed to examine the anti-obesity effects of 70% ethanol extracts of immature Citrus unshiu fruits and their solvent fractions (n-hexane, ethyl acetate, n-butanol, and water) on 3T3-L1 cells, as well as to explore the underlying molecular mechanisms. Additionally, this study was conducted to identify the bioactive components responsible for the anti-obesity effects. Among the fractions, the hexane fraction exhibited the most potent inhibitory effect on lipid accumulation in 3T3-L1 cells without inducing cytotoxicity. Notably, this effect was concentration-dependent. This fraction also inhibited adipogenesis during the differentiation of 3T3-L1 preadipocytes by downregulating the expression of CCAAT/enhancer-binding proteins (C/EBP), peroxisome proliferator-activated receptor-γ (PPARγ), sterol regulatory element-binding protein (SREBP), fatty acid synthase (FAS), and fatty acid binding protein 4 (FABP4). Moreover, the hexane fraction modulated the activity of AMP-activated protein kinase (AMPK) and mitogen-activated protein kinase (MAPK), both of which play critical roles in lipid metabolism. Specifically, it induced AMPK activation while downregulating MAPK signaling. Phytochemical analysis identified phytol, hexatriacontane, tangeretin, and nobiletin as the main bioactive components responsible for the observed anti-obesity effects of ICE. Overall, our results revealed that ICE exhibited notable anti-obesity activity by targeting the AMPK and MAPK signaling pathways, highlighting its potential as a natural therapeutic agent for obesity management.
Recent advancement in OMICS approaches to enhance abiotic stress tolerance in legumes
The world is facing rapid climate change and a fast-growing global population. It is believed that the world population will be 9.7 billion in 2050. However, recent agriculture production is not enough to feed the current population of 7.9 billion people, which is causing a huge hunger problem. Therefore, feeding the 9.7 billion population in 2050 will be a huge target. Climate change is becoming a huge threat to global agricultural production, and it is expected to become the worst threat to it in the upcoming years. Keeping this in view, it is very important to breed climate-resilient plants. Legumes are considered an important pillar of the agriculture production system and a great source of high-quality protein, minerals, and vitamins. During the last two decades, advancements in OMICs technology revolutionized plant breeding and emerged as a crop-saving tool in wake of the climate change. Various OMICs approaches like Next-Generation sequencing (NGS), Transcriptomics, Proteomics, and Metabolomics have been used in legumes under abiotic stresses. The scientific community successfully utilized these platforms and investigated the Quantitative Trait Loci (QTL), linked markers through genome-wide association studies, and developed KASP markers that can be helpful for the marker-assisted breeding of legumes. Gene-editing techniques have been successfully proven for soybean, cowpea, chickpea, and model legumes such as Medicago truncatula and Lotus japonicus . A number of efforts have been made to perform gene editing in legumes. Moreover, the scientific community did a great job of identifying various genes involved in the metabolic pathways and utilizing the resulted information in the development of climate-resilient legume cultivars at a rapid pace. Keeping in view, this review highlights the contribution of OMICs approaches to abiotic stresses in legumes. We envisage that the presented information will be helpful for the scientific community to develop climate-resilient legume cultivars.
1-Acetyl-β-Carboline from a Jeju Gotjawal Strain Lentzea sp. JNUCC 0626 and Its Melanogenic Stimulating Activity in B16F10 Melanoma Cells
The genus Lentzea is a prolific source of bioactive and structurally diverse secondary metabolites. We isolated a novel strain, Lentzea sp. JNUCC 0626, from Hwasun Gotjawal on Jeju Island, Korea. Based on 16S rRNA partial gene sequence analysis, strain JNUCC 0626 is closely related to Lentzea isolaginshaensis NX62 (99.41% similarity), Lentzea pudingi DHS C021 (99.31%), and Lentzea cavernae SYSU K10001 (99.26%). From the fermentation broth of JNUCC 0626, we isolated 1-acetyl-β-carboline, whose structure was established using IR, HR-ESI-MS, and 1D- and 2D-NMR techniques. 1-acetyl-β-carboline was found to activate melanogenesis in mouse B16F10 cells without cytotoxicity at concentrations up to 50 μM. At this concentration, the compound increased melanin content by 27.44% and tyrosinase activity by 240.64% compared to the control, by upregulating key melanogenic enzymes, including tyrosinase, TRP-1, TRP-2, and microphthalmia-associated transcription factor (MITF), a central regulator of melanogenesis. In addition, 1-acetyl-β-carboline significantly inhibited ERK phosphorylation, reducing it by 20.79% at a concentration of 12.5 μM and by 25.63% at 25 μM. This inhibition supports the hypothesis that 1-acetyl-β-carboline enhances melanin synthesis by upregulating MITF and melanogenic enzymes via the ERK signaling pathway. This study aimed to isolate and identify 1-acetyl-β-carboline from a novel strain of Lentzea sp. JNUCC 0626, discovered in Gotjawal, Jeju Island, and to evaluate its effect on melanin production in B16F10 melanoma cells. Skin irritation tests on 32 subjects confirmed its safety for topical use, and the findings suggest that 1-acetyl-β-carboline, which enhances melanogenesis without cytotoxicity, holds promise as a therapeutic agent for hypopigmentation-related conditions or as a cosmetic ingredient.
Analysis of the Setomimycin Biosynthetic Gene Cluster from Streptomyces nojiriensis JCM3382 and Evaluation of Its α-Glucosidase Inhibitory Activity Using Molecular Docking and Molecular Dynamics Simulations
The formation of atroposelective biaryl compounds in plants and fungi is well understood; however, polyketide aglycone synthesis and dimerization in bacteria remain unclear. Thus, the biosynthetic gene cluster (BGC) responsible for antibacterial setomimycin production from Streptomyces nojiriensis JCM3382 was examined in comparison with the BGCs of spectomycin, julichromes, lincolnenins, and huanglongmycin. The setomimycin BGC includes post-polyketide synthase (PKS) assembly/cycling enzymes StmD (C-9 ketoreductase), StmE (aromatase), and StmF (thioesterase) as key components. The heterodimeric TcmI-like cyclases StmH and StmK are proposed to aid in forming the setomimycin monomer. In addition, StmI (P-450) is predicted to catalyze the biaryl coupling of two monomeric setomimycin units, with StmM (ferredoxin) specific to the setomimycin BGC. The roles of StmL and StmN, part of the nuclear transport factor 2 (NTF-2)-like protein family and unique to setomimycin BGCs, could particularly interest biochemists and combinatorial biologists. α-Glucosidase, a key enzyme in type 2 diabetes, hydrolyzes carbohydrates into glucose, thereby elevating blood glucose levels. This study aimed to assess the α-glucosidase inhibitory activity of EtOAc extracts of JCM 3382 and setomimycin. The JCM 3382 EtOAc extract and setomimycin exhibited greater potency than the standard inhibitor, acarbose, with IC50 values of 285.14 ± 2.04 μg/mL and 231.26 ± 0.41 μM, respectively. Molecular docking demonstrated two hydrogen bonds with maltase-glucoamylase chain A residues Thr205 and Lys480 (binding energy = −6.8 kcal·mol−1), two π–π interactions with Trp406 and Phe450, and one π–cation interaction with Asp542. Residue-energy analysis highlighted Trp406 and Phe450 as key in setomimycin’s binding to maltase-glucoamylase. These findings suggest that setomimycin is a promising candidate for further enzymological research and potential antidiabetic therapy.
Label-free shotgun proteomics and metabolite analysis reveal a significant metabolic shift during citrus fruit development
Label-free LC-MS/MS-based shot-gun proteomics was used to quantify the differential protein synthesis and metabolite profiling in order to assess metabolic changes during the development of citrus fruits. Our results suggested the occurrence of a metabolic change during citrus fruit maturation, where the organic acid and amino acid accumulation seen during the early stages of development shifted into sugar synthesis during the later stage of citrus fruit development. The expression of invertases remained unchanged, while an invertase inhibitor was up-regulated towards maturation. The increased expression of sucrose-phosphate synthase and sucrose-6-phosphate phosphatase and the rapid sugar accumulation suggest that sucrose is also being synthesized in citrus juice sac cells during the later stage of fruit development.
Enterotype-Specific Effects of Red Beetroot (Beta vulgaris L.) Powder and Betanin on Human Gut Microbiota: A Preliminary Study Based on In Vitro Fecal Fermentation Model
Red beetroots, rich in betanin, may act as prebiotics and impact gut microbiota. Because the human gut microbiota is unique to each person, the effectiveness of prebiotics varies with the enterotype. In this study, we hypothesized that the effects of red beetroot powder (RP) and betanin pigment (BP) would differ depending on the enterotype. Fecal samples from 30 subjects were analyzed and categorized into three enterotypes: Phocaeicola, Prevotella, and Bifidobacterium. Feces were collected from one representative subject from each enterotype cluster for fermentation. Results showed that RP and BP affected microbiota composition and short-chain fatty acid (SCFA) production differently across enterotypes. The Bifidobacterium cluster showed significantly reduced alpha diversity, with the direction of change in the gut microbiota composition being different from that of other subjects. Additionally, SCFAs significantly increased, with the highest increase in the Bifidobacterium cluster. In this cluster, metabolic pathways related to SCFAs (i.e., starch and sucrose metabolism and glycolysis/gluconeogenesis) were altered. Conversely, Prevotella-dominant feces exhibited fewer changes in SCFAs and a lower increase in Bifidobacterium abundance than the others. These findings highlight that RP and BP elicit enterotype-specific responses in the gut microbiota composition and SCFA production, emphasizing the importance of enterotypes in personalized nutrition.
Effects of Cooking and Processing Methods on Phenolic Contents and Antioxidant and Anti-Proliferative Activities of Broccoli Florets
We investigated the effects of cooking (steaming and microwaving) and processing (freeze-drying and hot-air-drying) methods on the antioxidant activity of broccoli florets. 2,2-diphenyl-1-picrylhydrazyl (DPPH•), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•), and alkyl• free radical scavenging assays were employed to assess anti-oxidant potentials. The cytoprotective effect against oxidative damage induced by H2O2 was studied using hepatocellular carcinoma (HepG2) cells. Anti-proliferative effects were assessed in MCF-7 and MDA-MB-231 breast cancer cells. L-sulforaphane in broccoli extracts was quantified using high-performance liquid chromatography (HPLC). Steam and microwave treatments caused increases in total polyphenol content (TPC), whereas the total flavonoid content (TFC) decreased following steam treatment. A slight increase in TFC was observed in the microwaved samples. Extracts of all broccoli samples showed almost identical radical scavenging and cytoprotective effects. HPLC demonstrated that steamed (3 min)-freeze-dried (F-S3) and microwaved (2 min)-freeze-dried (F-M2) samples exhibited elevated levels of L-sulforaphane. In addition, the F-S3 and F-M2 extracts displayed strong anti-proliferative effects in MCF-7 cells, which correlated with L-sulforaphane content. As we observed no significant decrease in the antioxidant activity of broccoli florets, the cooking and processing methods and conditions studied here are recommended for broccoli.
Inhibitory Effects of Bidens pilosa Plant Extracts on the Growth of the Bloom-Forming Alga Microcystis aeruginosa
Algal blooms are one of the greatest aquatic environmental concerns, and the control of algal blooms has become a great challenge in recent years. In this study, we evaluated the effects of Bidens pilosa plant extracts in comparison to those of several widespread plants, including rice (Oryza sativa), Pistia stratiotes, Eichhornia crassipes, and Pteris vittata, on the growth of the bloom-forming blue-green alga Microcystis aeruginosa. Both ethanolic and methanolic extracts of B. pilosa, in contrast to the other plant extracts, exhibited high inhibitory effects on M. aeruginosa growth at a concentration of 500 mg/L (dry weight equivalent, DWE). The inhibition efficiency in terms of the cell density and chlorophyll a concentration significantly reached 84–88% (p < 0.05). In these treatments, a change in algal culture color (from green to brown) and cell death were obviously observed. When we determined the effective concentrations, the B. pilosa extract at concentrations of 250 and 500 mg/L DWE showed significant inhibitory effects on M. aeruginosa growth (p < 0.05), whereas lower concentrations (50–125 mg/L DWE) showed slight or no effects. These data indicate that B. pilosa plant extracts could be used to control M. aeruginosa algal blooms.
Sorption and leaching characteristics of pesticides in volcanic ash soils of Jeju Island, Korea
It is important to evaluate leaching behavior in agricultural soils to prevent the pollution of groundwater by pesticides. We identified the distribution coefficients (K d ) of ten pesticides with different physicochemical properties and compared their leaching characteristics using wick lysimeters from three distinct soil types on Jeju Island. The K d values varied by pesticide and soil, but were within the range of 1.2 to 4231 L kg −1 . Based on the European standard (K d  < 10 L kg −1 ), six pesticides (alachlor, ethoprophos, carbofuran, napropamide, tebuconazole, and etridiazole) were mobile in at least one tested soil, and their soil organic carbon affinity was ≤ 5.811. This value differed greatly from the other pesticides (16.533 and higher). The solubility of the six mobile pesticides was ≥ 32 mg L −1 , which substantially differed from the other pesticides (≤ 0.71 mg L −1 ). Thus, we conclude that our mobility assessment, which is based on K d values, can be used to predict the leaching of pesticides in the volcanic ash soils of Jeju Island. The use of pesticides should be strictly controlled to reduce the possibility of groundwater contamination.
Complete Genome Sequence of the Butirosin-Producing Bacillus vitellinus NBRC 13296 and Its Reclassification to Paenibacillus chitinolyticus
Butirosins are naturally occurring aminoglycoside (AG) antibiotics featuring a 4,5-disubstituted 2-deoxystreptamine (2-DOS) with a (2S)-4-amino-2-hydroxybutyrate (AHBA) side chain. This side chain has been shown to confer resistance against AG-modifying enzymes, leading to ongoing studies on the butirosin biosynthetic pathway and the corresponding enzymes. Butirosin is produced by Niallia (formerly Bacillus) circulans and Bacillus vitellinus, with most research focused on the first strain. To date, no whole-genome analysis has been performed on B. vitellinus. In this study, we sequenced the complete genome of B. vitellinus NBRC 13296 and performed a comparative analysis of different butirosin biosyntheric gene clusters (BGCs), including those from N. circulans. The complete genome of B. vitellinus NBRC 13296 comprises a 6,331,192-base circular chromosome with GC content of 52.68%. The annotation revealed the presence of 5605 CDSs, 70 tRNA genes, 30 rRNA genes, and 3 ncRNA genes in NBRC 13296. The highest dDDH and ANI values between NBRC 13296 and the most closely related type strain, Paenibacillus chitinolyticus KCCM 41,400, were 97.8% and 98.66%, respectively. Based on these genome-based comparative analyses, we propose reclassifying B. vitellinus NBRC 13296 as P. chitinolyticus. Genome mining revealed 18 gene clusters encoding the biosynthesis of diverse secondary metabolites in the genome of B. vitellinus NBRC 13296, indicating the enormous biosynthetic potential of this strain. The predicted structural diversity of the secondary metabolites includes aminoglycosides, PKS, NRPS, PKS–NRPS hybrids, metallophores, phosphonates, terpenes, β-lactones, and RiPP peptides. We then comparatively characterized the butirosin BGCs previously studied in several N. circulans strains. Additionally, the comparative genome analysis revealed complete butirosin BGCs identified from P. chitinolyticus KCCM 41,400, P. chitinolyticus NRRL B-23119, P. chitinolyticus NRRL B-23120, P. chitinolyticus B-14908, P. chitinolyticus YSY-3.1, P. chitinolyticus JMW06, Paenibacillus sp. GbtcB18, Paenibacillus sp. HGH0039, and Paenibacillus sp. MZ04-78.2. Finally, we identified the core region consisting of BtrS, BtrN, BtrM, BtrL, BtrA, BtrB, BtrC, BtrD, BtrD, BtrE, BtrF, BtrG, BtrH, BtrI, BtrI, BtrJ, BtrK, BtrO, BtrP, and BtrV, followed by an upstream region organizing BtrQ, BtrW, BtrX, BtrY, and BtrZ in the same transcriptional direction and sequential genetic arrangement, and a downstream region organizing various proteins based on BtrT, BtrR2, BtrU, and BtrR1. Our study provides insights into the reclassification of B. vitellinus NBRC 13296 to P. chitinolyticus and suggests the need for continued studies on butirosin biosynthesis from an enzymatic perspective.