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1.
Artigo em Inglês | MEDLINE | ID: mdl-37436803

RESUMO

A Gram-stain-negative, non-motile by gliding and moderately halophilic rod-shaped bacterium HN-2-9-2T was isolated from seawater in Tongyeong, Republic of Korea. The strain grew at concentrations of 0.5‒7 % (w/v) NaCl, at pH 5.5‒8.5 and in a temperature range of 18‒45 °C. HN-2-9-2T shared the highest 16S rRNA gene sequence percentage with Salinimicrobium xinjiangense BH206T (98.2 %). The average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA-DNA hybridisation (dDDH) values between HN-2-9-2T and the S. xinjiangense BH206T were 76.0 %, 81.9 % and 19.7 %, respectively. The genome comprised 3 509 958 bp with a DNA G+C content of 43.0%. HN-2-9-2T contained MK-6 as the sole menaquinone. The predominant fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C17 : 0 3-OH, iso-C16 : 0, iso-C15 : 1G and summed feature 9, comprising iso-C17 : 1ω6c/C16 : 1 10-methyl. The polar lipids contained phosphatidylethanolamine, one unidentified phospholipid, two unidentified aminolipids, an unidentified glycolipid and six unidentified lipids. The polyphasic taxonomic properties indicate that the strain represents a novel species within the genus Salinimicrobium, for which the name Salinimicrobium tongyeongense sp. nov. is proposed. The type strain is HN-2-9-2T (=KCTC 82934T=NBRC 115920T).


Assuntos
Ácidos Graxos , Água do Mar , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Composição de Bases , Filogenia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Análise de Sequência de DNA , Água do Mar/microbiologia , Vitamina K 2/química
2.
Pharmaceutics ; 15(6)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37376117

RESUMO

The purpose of this study is to develop and evaluate a self-microemulsifying drug delivery system (SMEDDS) to improve the oral absorption of poorly water-soluble olaparib. Through the solubility test of olaparib in various oils, surfactants and co-surfactants, pharmaceutical excipients were selected. Self-emulsifying regions were identified by mixing the selected materials at various ratios, and a pseudoternary phase diagram was constructed by synthesizing these results. The various physicochemical properties of microemulsion incorporating olaparib were confirmed by investigating the morphology, particle size, zeta potential, drug content and stability. In addition, the improved dissolution and absorption of olaparib were also confirmed through a dissolution test and a pharmacokinetic study. An optimal microemulsion was generated in the formulation of Capmul® MCM 10%, Labrasol® 80% and PEG 400 10%. The fabricated microemulsions were well-dispersed in aqueous solutions, and it was also confirmed that they were maintained well without any problems of physical or chemical stability. The dissolution profiles of olaparib were significantly improved compared to the value of powder. Associated with the high dissolutions of olaparib, the pharmacokinetic parameters were also greatly improved. Taken together with the results mentioned above, the microemulsion could be an effective tool as a formulation for olaparib and other similar drugs.

3.
Antonie Van Leeuwenhoek ; 116(8): 791-799, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37227603

RESUMO

The taxonomic position of strain EF45031T, isolated from the Neungam Carbonate hot spring, was examined using the polyphasic taxonomic approach. Strain EF45031T shared the highest percentage of 16S rRNA gene sequence with Brachybacterium nesterenkovii CIP 104813 T (97.7%). The average nucleotide identity (ANI), average amino acid identity (AAI), and digital DNA-DNA hybridization (dDDH) values between strain EF45031T and the type strains B. nesterenkovii CIP 104813 T and B. phenoliresistens Phenol-AT were 77.0%, 69.15%, 21.9% and 75.73%, 68.81%, 20.5%, respectively. Phylogenomic analysis using an up-to-date bacterial core gene (UBCG) set revealed that strain EF45031T belonged to the genus Brachybacterium. Growth occurred between 25 and 50 ℃ at pH 6.0-9.0 and could tolerate salinity up to 5% (w/v). Strain had anteiso-C15:0 and anteiso-C17:0 as major fatty acids. Menaquinone-7 (MK-7) was the predominant respiratory menaquinone. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, three aminolipids, and two unidentified glycolipids. The cell-wall peptidoglycan contained meso-diaminopimelic acid as a diagnostic diamino acid. The genome comprised 2,663,796 bp, with a G + C content of 70.9%. Stress-responsive periplasmic chaperone/protease coding genes were identified in the genome of EF45031T and were not detected in other Brachybacterium species. The polyphasic taxonomic properties indicate that the strain represents a novel species within the genus Brachybacterium, for which the name Brachybacterium sillae sp. nov. is proposed. The type strain is EF45031T (= KCTC 49702 T = NBRC 115869 T).


Assuntos
Actinomycetales , Fontes Termais , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Ácidos Graxos/química , Filogenia , Vitamina K 2/química , DNA , DNA Bacteriano/genética , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana
4.
Microb Cell Fact ; 22(1): 98, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170276

RESUMO

BACKGROUND: Palifermin (trade name Kepivance®) is an amino-terminally truncated recombinant human keratinocyte growth factor 1 (KGF-1) with 140 residues that has been produced using Escherichia coli to prevent and treat oral mucositis following radiation or chemotherapy. In this study, an amino-terminally shortened KGF-1 variant with 135 residues was produced and purified in E. coli, and its cell proliferation activity was evaluated. RESULTS: We expressed soluble KGF-1 fused to thioredoxin (TRX) in the cytoplasmic fraction of E. coli to improve its production yield. However, three N-truncated forms (KGF-1 with 140, 138, and 135 residues) were observed after the removal of the TRX protein from the fusion form by cleavage of the human enterokinase light chain C112S (hEKL C112S). The shortest KGF-1 variant, with 135 residues, was expressed by fusion with TRX via the hEKL cleavage site in E. coli and purified at high purity (> 99%). Circular dichroism spectroscopy shows that purified KGF-1135 had a structure similar to that of the KGF-1140 as a random coiled form, and MCF-7 cell proliferation assays demonstrate its biological activity. CONCLUSIONS: We identified variations in N-terminus-truncated KGF-1 and selected the most stable form. Furthermore, by a simple two-step purification, highly purified KGF-1135 was obtained that showed biological activity. These results demonstrate that KGF-1135 may be considered an alternative protein to KGF-1.


Assuntos
Escherichia coli , Fator 7 de Crescimento de Fibroblastos , Humanos , Fator 7 de Crescimento de Fibroblastos/genética , Fator 7 de Crescimento de Fibroblastos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo
5.
Microbiol Spectr ; : e0366022, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36786576

RESUMO

The evolution of the bacterial phosphotransferase system (PTS) linked to glycolysis is dependent on the availability of naturally occurring sugars. Although bacteria exhibit sugar specificities based on carbon catabolite repression, the acquisition and evolvability of the cellular sugar preference under conditions that are suboptimal for growth (e.g., environments rich in a rare sugar) are poorly understood. Here, we generated Escherichia coli mutants via a retro-aldol reaction to obtain progeny that can utilize the rare sugar d-tagatose. We detected a minimal set of adaptive mutations in the d-fructose-specific PTS to render E. coli capable of d-tagatose utilization. These E. coli mutant strains lost the tight regulation of both the d-fructose and N-acetyl-galactosamine PTS following deletions in the binding site of the catabolite repressor/activator protein (Cra) upstream from the fruBKA operon and in the agaR gene, encoding the N-acetylgalactosamine (GalNAc) repressor, respectively. Acquired d-tagatose catabolic pathways then underwent fine-tuned adaptation via an additional mutation in 1-phosphofructose kinase to adjust metabolic fluxes. We determined the evolutionary trajectory at the molecular level, providing insights into the mechanism by which enteric bacteria evolved a substrate preference for the rare sugar d-tagatose. Furthermore, the engineered E. coli mutant strain could serve as an in vivo high-throughput screening platform for engineering non-phosphosugar isomerases to produce rare sugars. IMPORTANCE Microorganisms generate energy through glycolysis, which might have preceded a rapid burst of evolution, including the evolution of cellular respiration in the primordial biosphere. However, little is known about the evolvability of cellular sugar preferences. Here, we generated Escherichia coli mutants via a retro-aldol reaction to obtain progeny that can utilize the rare sugar d-tagatose. Consequently, we identified mutational hot spots and determined the evolutionary trajectory at the molecular level. This provided insights into the mechanism by which enteric bacteria evolved substrate preferences for various sugars, accounting for the widespread occurrence of these taxa. Furthermore, the adaptive laboratory evolution-induced cellular chassis could serve as an in vivo high-throughput screening platform for engineering tailor-made non-phosphorylated sugar isomerases to produce low-calorigenic rare sugars showing antidiabetic, antihyperglycemic, and antitumor activities.

6.
Nutrients ; 15(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36678181

RESUMO

Microbial fermentation provides a valorization strategy, through biotransformation, to convert plant-derived raw materials into health-promoting agents. In this study, we have investigated the antioxidative activity of Abelmoschus manihot fermented with various Bacillaceae strains from specific environments and demonstrated the anti-inflammatory effects of Bacillus licheniformis CP6 fermented A. manihot extract (FAME) in lipopolysaccharide (LPS)-stimulated Raw264.7 macrophages. Of 1500 bacteria isolated from various specific environments, 47 extracellular protease- and amylase-producing strains with qualified presumption safety status, belonging to the family Bacillaceae, were selected for A. manihot fermentation. Among them, strain CP6, a halophilic bacterium isolated from Tongyeong seawater in Korea and identified as B. licheniformis, showed the highest antioxidant activity. In particular, FAME exerted anti-inflammatory effects on LPS-stimulated Raw264.7 macrophages. Consequently, FAME had a potent inhibitory effect on nitric oxide (NO) production in LPS-stimulated macrophages, without cytotoxicity. Moreover, FAME downregulated LPS-induced pro-inflammatory mediator and enzyme levels in LPS-induced Raw264.7 cells, including IL-1ß, IL-6, TNF-α, iNOS, and COX-2, compared to levels when cells were incubated in A. manihot extract (IAME). Further detailed characterization indicated that FAME suppresses inflammation by blocking NF-κB via IKK phosphorylation inhibition and IκB-α degradation and by downregulating NO production, and inflammatory mediators also decreased NF-κB translocation. Furthermore, FAME inhibited LPS-stimulated activation of MAPKs, including ERK1/2, JNK, and p38, compared to that with either IAME. Therefore, we suggest that FAME could be used for inflammation-related disorders.


Assuntos
Abelmoschus , Bacillus licheniformis , NF-kappa B/metabolismo , Transdução de Sinais , Bacillus licheniformis/metabolismo , Lipopolissacarídeos/farmacologia , Fermentação , Anti-Inflamatórios/farmacologia , Inflamação , Extratos Vegetais/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo
7.
Arch Microbiol ; 205(1): 23, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36509934

RESUMO

The Gram-positive, nonmotile, rod-shaped bacterium EF45044T was isolated from a hot spring in Chungju, South Korea. The strain was able to grow at concentrations of 0‒5% (w/v) NaCl, at pH 6.0‒10.0 and in the temperature range of 18‒50 °C. Strain EF45044T showed the highest 16S rRNA gene sequence similarity (98.2%) with Microbacterium ketosireducens DSM 12510T, and the digital DNA‒DNA hybridization (dDDH), average amino acid identity (AAI), and average nucleotide identity (ANI) values were all lower than the accepted species threshold. Strain EF45044T contained MK‒12 and MK‒13 as the predominant respiratory quinones and anteiso‒C17:0, anteiso‒C15:0, and iso‒C16:0 as the major fatty acids. Diphosphatidylglycerol, phosphatidylglycerol, and glycolipid were detected as the major polar lipids. The cell-wall peptidoglycan contained ornithine. The DNA G + C content was 71.4 mol%. Based on the polyphasic data, strain EF45044T (= KCTC 49703T) presents a novel species of the genus Microbacterium, for which the name Microbacterium neungamense sp. nov. is proposed.


Assuntos
Ácidos Graxos , Microbacterium , RNA Ribossômico 16S/genética , Microbacterium/genética , Filogenia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Análise de Sequência de DNA , Ácidos Graxos/análise , Hibridização de Ácido Nucleico , Fosfolipídeos/química
8.
Microorganisms ; 10(12)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36557626

RESUMO

Thermophiles that produce extracellular hydrolases are of great importance due to their applications in various industries. Thermophilic enzymes are of interest for industrial applications due to their compatibility with industrial processes, and the availability of the organisms is essential to develop their full potential. In this study, a culture-dependent approach was used to identify thermophilic bacteria from five hot springs in Republic of Korea. Characterization, taxonomic identification, and extracellular hydrolase (amylase, lipase, and protease) activity of 29 thermophilic bacterial isolates from the Neungam carbonate, Mungang sulfur, Deokgu, Baegam, and Dongnae hot springs were investigated. Identification based on the full-length 16S rRNA gene sequence revealed that strains belonged to the phylum Bacillota and were classified as Aeribacillus, Bacillus, Caldibacillus, Geobacillus, and Thermoactinomyces genera. It was found that 22 isolates could produce at least one extracellular enzyme. Geobacillus, representing 41.4% of the isolates, was the most abundant. The highest amount of proteolytic and lipolytic enzymes was secreted by strains of the genus Geobacillus, whereas Caldibacillus species produced the highest amount of amylolytic enzyme. The Geobacillus species producing hydrolytic extracellular enzymes appeared to be the most promising.

9.
Pharmaceutics ; 14(8)2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-36015244

RESUMO

Biodegradable nanoparticles (NPs) are preferred as drug carriers because of their effectiveness in encapsulating drugs, ability to control drug release, and low cytotoxicity. Although poly(lactide co-glycolide) (PLGA)-based NPs have been used for controlled release strategies, they have some disadvantages. This study describes an approach using biodegradable polyhydroxyalkanoate (PHA) to overcome these challenges. By varying the amount of PHA, NPs were successfully fabricated by a solvent evaporation method. The size range of the NPS ranged from 137.60 to 186.93 nm, and showed zero-order release kinetics of paclitaxel (PTX) for 7 h, and more sustained release profiles compared with NPs composed of PLGA alone. Increasing the amount of PHA improved the PTX loading efficiency of NPs. Overall, these findings suggest that PHA can be used for designing polymeric nanocarriers, which offer a potential strategy for the development of improved drug delivery systems for sustained and controlled release.

10.
J Nanosci Nanotechnol ; 21(7): 4089-4092, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33715751

RESUMO

The aim of this study was to improve the skin accumulation of hydroxycitric acid by using ethosomes with nanosize. We fabricated nanosized ethosome for the topical delivery of hydrophilic hydroxycitric acid and evaluated their physical properties and furthermore cytotoxicity. As results, in cell-based experiments, the use of ethosomes encapsulating hydroxycitric acid extract reduced the lipid droplet deposition in differentiated adipocytes, which was visualized by Oil Red O staining assay and also quantitatively measured by a triglyceride assay. The observed reduction in lipid droplet deposition occurred in a hydroxycitric acid extract concentration-dependent manner. In addition, the high accumulation of hydroxycitric acid in murine skin (66.28%) was observed following treatment with hydroxycitric acid extract-loaded ethosomes compared with treatment with hydroxycitric acid alone (1.19%) without ethosome as a nanocarrier. Based on these results, our findings showed that nanosized ethosomes improved the topical delivery of hydroxycitric acid and thus reduced lipid droplet deposition in adipocytes.


Assuntos
Lipossomos , Absorção Cutânea , Animais , Citratos , Gotículas Lipídicas , Camundongos , Pele/metabolismo
11.
Pharmaceutics ; 12(4)2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32272811

RESUMO

The aim of this study was to develop a coenzyme Q10 (CoQ10) microemulsion system with improved solubility, penetration, and wound healing efficacy. Based on the pseudo-ternary diagram, microemulsions containing isopropyl myristate (IPM), Cremophor EL®, and Transcutol® HP were selected and confirmed to be nanosized (<20 nm) and thermodynamically stable based on the dilution and thermodynamic stability tests. The CoQ10-loaded microemulsion with a surfactant/co-surfactant (S/CoS) ratio of 2:1 (w/w %) demonstrated a higher permeation efficacy compared to microemulsions with S/CoS ratio of 3:1 or 4:1 (w/w %). Additionally, the CoQ10-loaded microemulsion with an S/CoS ratio of 2:1 demonstrated a relatively rapid wound healing effect in keratinocytes and fibroblasts. Overall, these data suggest that a microemulsion based on IPM, Cremophor EL®, and Transcutol® HP could be an effective vehicle for the topical administration of CoQ10 and could be utilized for the application of other therapeutic agents that have difficulty in penetrating the skin.

12.
Enzyme Microb Technol ; 134: 109479, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32044026

RESUMO

Mangiferin, a major constituent of Mangifera indica L., has attracted substantial attention due to its anti-oxidant, anti-diabetic, anti-inflammatory, and anti-microbial activities. However, its poor solubility in water limits its use in food and pharmaceutical industries. In this study, novel mangiferin-(1→6)-α-d-glucopyranoside (Mg-G1) was enzymatically synthesized from mangiferin and sucrose using glucansucrase from Leuconostoc mesenteroides B-512F/KM, and optimized using response surface methodology. The water solubility of Mg-G1 was found to be 824.7 mM, which is more than 2300-fold higher than that of mangiferin. Mg-G1 also showed DPPH radical scavenging activity and superoxide dismutase (SOD)-like scavenging activity, which were 4.77- and 3.71-fold higher than that of mangiferin, respectively. Mg-G1 displayed inhibitory activity against human intestinal maltase and COX-2. Thus, the novel glucosylated mangiferin may be used as an ingredient in functional food and pharmaceutical application.


Assuntos
Glucosídeos/biossíntese , Glicosiltransferases/metabolismo , Leuconostoc mesenteroides/enzimologia , Mangifera/química , Xantonas/metabolismo , Antioxidantes/metabolismo , Inibidores de Ciclo-Oxigenase 2/metabolismo , Humanos , Solubilidade , Sacarose/metabolismo , Superóxido Dismutase/metabolismo , alfa-Glucosidases/metabolismo
13.
Enzyme Microb Technol ; 132: 109412, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31731958

RESUMO

Transglycosylation is one of enzymatic methods to improve the physical and biochemical properties of various functional compounds. In this study, stevioside glucosides were synthesized using sucrose as a substrate, stevioside (Ste) as an acceptor, and dextransucrase from Leuconostoc mesenteroides B-512 F/KM. The highest Ste conversion yield of 98% was obtained with 50 mg/mL Ste, 800 mM sucrose, and dextransucrase 4 U/mL at 28 °C for 6 h. The concentration of Ste was unchanged while of Ste-G1 was increased from 7.7 mM to 9.1 mM as the Ste acceptor reaction digest was treated with dextranase from Lipomyces starkeyi. Ste-G1 (13-O-ß-sophorosyl-19-O-ß-isomaltosyl-steviol), Ste-G2 (13-O-(ß-(1→6) glucosyl)-ß-glucosylsophorosyl-19-O-ß-isomaltosyl-steviol), and Ste-G2' (13-O-ß-sophorosyl-19-O-ß-isomaltotriosyl-steviol) were determined by NMR. These glucosylated Ste showed increased stabilities at pH 2, 60 °C for 48 h as compared to Ste. Ste-G1, Ste-G2, and Ste-G2' inhibited the insoluble glucan synthesis from sucrose by mutansucrase from Streptococcus muntans by the transfer of the glucosyl group of sucrose to Ste-G1, Ste-G2, and Ste-G2'. The relative water solubility of curcumin, pterostilbene or idebenone was increased by Ste or Ste glucosides treatment. Ste and Ste-G1 restored cell viability in RAW264.7 cells at concentrations up to 8 mg/mL and inhibited nitric oxide production in LPS-induced RAW264.7 cells with IC50 of 3.29 and 1.87 mg/mL.


Assuntos
Dextranase/metabolismo , Diterpenos do Tipo Caurano/química , Glucosídeos/química , Glucosiltransferases/metabolismo , Sacarose/química , Edulcorantes/química , Leuconostoc mesenteroides/enzimologia , Espectroscopia de Ressonância Magnética , Polimerização , Solubilidade
14.
Foods ; 8(10)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31581594

RESUMO

D-allulose, a C-3 epimer of D-fructose, is a rare monosaccharide used as a food ingredient or a sweetener. In the present study, the in vitro metabolic stability of D-allulose was examined in biorelevant media, that is, simulated gastric fluid (SGF) and fasted state simulated intestinal fluid (FaSSIF) containing digestive enzymes, and in cryopreserved human and rat hepatocytes. The hepatocyte metabolic stabilities of D-allulose were also investigated and compared with those of fructose and erythritol (a sugar-alcohol with no calorific value). D-allulose was highly stable in SGF (97.8% remained after 60 min) and in FaSSIF (101.3% remained after 240 min), indicating it is neither pH-labile nor degraded in the gastrointestinal tract. D-allulose also exhibited high levels of stability in human and rat hepatocytes (94.5-96.8% remained after 240 min), whereas fructose was rapidly metabolized (43.1-52.6% remained), which suggested these two epimers are metabolized in completely different ways in the liver. The effects of D-allulose on glucose and fructose levels were negligible in hepatocytes. Erythritol was stable in human and rat hepatocytes (102.1-102.9% remained after 240 min). Intravenous pharmacokinetic studies in rats showed D-allulose was eliminated with a mean half-life of 72.2 min and a systemic clearance of 15.8 mL/min/kg. Taken together, our results indicate that D-allulose is not metabolized in the liver, and thus, unlikely to contribute to hepatic energy production.

15.
J Cosmet Sci ; 70(5): 235-245, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31596226

RESUMO

Mistletoes, hemiparasites, contain many components with various biological activities and have been used in cosmetics industry. Loranthacease (1,000 species) and Viscaceae (550 species) have the most dominant species in mistletoes (nearly 1,600 species). It can be expected that the biological activities vary from species to species; therefore, we have tested Viscum album var. coloratum (Kom.) Ohwi (belonging to Santalaceae) and Loranthus tanakae Franch. & Sav. (belonging to Loranthacease) for a comparative study of their cosmetic properties, including antioxidant, antimelanogenic, and antiwrinkle activities. As results, the ethanol extract of L. tanakae had higher phenolic content and showed effective antioxidant activity and elastase inhibition. Meanwhile, the ethanol extract of V. album more effectively inhibited tyrosinase. Comparing with ethanol extracts, the water extracts of both mistletoes showed lower biological efficacy than the ethanol extracts or no significant effect. Thus, these results show that different extracts of mistletoe have different levels of biological activities, presumably because of the differences in their phytochemical profiles and because of the different extraction methods used.


Assuntos
Cosméticos , Erva-de-Passarinho , Viscum album , Antioxidantes , Extratos Vegetais
16.
Biotechnol Bioprocess Eng ; 24(2): 282-287, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32218683

RESUMO

Streptococcus mutans plays an important role in the development of dental caries in humans by synthesizing adhesive insoluble glucans from sucrose by mutansucrase activity. To explore the anti-cariogenic characteristics of rubusoside (Ru), a natural sweetener component in Rubus suavissimus S. Lee (Rosaceae), we investigated the inhibitory effect of Ru against the activity of mutansucrase and the growth of Streptococcus mutans. Ru (50 mM) showed 97% inhibitory activity against 0.1 U/mL mutansucrase of S. mutans with 500 mM sucrose. It showed competitive inhibition with a K i value of 1.1 ± 0.2 mM and IC50 of 2.3 mM. Its inhibition activity was due to hydrophobic and hydrogen bonding interactions based on molecular docking analysis. Ru inhibited the growth of S. mutans as a bacteriostatic agent, with MIC and MBC values of 6 mM and 8 mM, respectively. In addition, Ru showed synergistic anti-bacterial activity when it was combined with curcumin. Therefore, Ru is a natural anti-cariogenic agent with anti-mutansucrase activity and antimicrobial activity against S. mutans. ELECTRONIC SUPPLEMENTARY MATERIAL ESM: The online version of this article (doi: 10.1007/s12257-018-0408-0) contains supplementary material, which is available to authorized users.

17.
Nutrients ; 10(12)2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30572580

RESUMO

D-allulose has recently received attention as a sugar substitute. However, there are currently no reports regarding its association with gastrointestinal (GI) tolerance. Thus, we performed a GI tolerance test for D-allulose in order to establish its daily acceptable intake level. When the dose of D-allulose was gradually increased in steps of 0.1 g/kg·Body Weight (BW) to identify the maximum single dose for occasional ingestion, no cases of severe diarrhea or GI symptoms were noted until a dose of 0.4 g/kg·BW was reached. Severe symptoms of diarrhea were noted at a dose of 0.5 g/kg·BW. Similarly, the GI tolerance test did not show any incidences of severe diarrhea or GI symptoms until a dose of 0.5 g/kg·BW was reached. A correlation analysis of the GI tolerance test for D-allulose and sugar revealed significantly higher frequencies of symptoms of diarrhea (p = 0.004), abdominal distention (p = 0.039), and abdominal pain (p = 0.031) after D-allulose intake. Increasing the total daily D-allulose intake gradually to 1.0 g/kg·BW for regular ingestion resulted in incidences of severe nausea, abdominal pain, headache, anorexia, and diarrheal symptoms. Based on these results, we suggest a maximum single dose and maximum total daily intake of D-Allulose of 0.4 g/kg·BW and 0.9 g/kg·BW, respectively.


Assuntos
Dor Abdominal/induzido quimicamente , Diarreia/induzido quimicamente , Frutose/efeitos adversos , Edulcorantes/efeitos adversos , Adulto , Relação Dose-Resposta a Droga , Feminino , Frutose/administração & dosagem , Humanos , Masculino , Náusea/induzido quimicamente , Edulcorantes/administração & dosagem , Adulto Jovem
18.
Food Sci Nutr ; 6(8): 2293-2300, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30510729

RESUMO

Makgeolli is a traditional Korean alcoholic rice beverage. It is brewed of ingredients containing starch, Nuruk, and water. In order to improve the quality and functionality of Makgeolli, the Rhizopus oligosporus fermented buckwheat containing 18.7 mg/kg of l-carnitine were utilized to brew l-carnitine fortified Makgeolli with rice. Makgeolli was prepared in two-stage fermentation method and total rutin and quercetin in each fermented buckwheat Makgeolli were increased 1.8-fold greater than buckwheat Makgeolli. DPPH antioxidant activity was enhanced in fermented buckwheat Makgeolli than buckwheat Makgeolli (21.9%-65.7%). The amounts of l-carnitine in rice Makgeolli, buckwheat Makgeolli, and fermented buckwheat Makgeolli were 0.9, 0.8-1.0, and 1.0-1.9 mg/L, respectively. The fermented buckwheat Makgeolli not only promoted health benefit by increasing l-carnitine and flavonols, but also made effective alcohol production (2.8%-8.4%) compared to common buckwheat Makgeolli, indicating the potential industrial application with health benefits.

19.
Nutrients ; 10(2)2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29385054

RESUMO

d-allulose is a rare sugar with zero energy that can be consumed by obese/overweight individuals. Many studies have suggested that zero-calorie d-allulose has beneficial effects on obesity-related metabolism in mouse models, but only a few studies have been performed on human subjects. Therefore, we performed a preliminary study with 121 Korean subjects (aged 20-40 years, body mass index ≥ 23 kg/m²). A randomized controlled trial involving placebo control (sucralose, 0.012 g × 2 times/day), low d-allulose (d-allulose, 4 g × 2 times/day), and high d-allulose (d-allulose, 7 g × 2 times/day) groups was designed. Parameters for body composition, nutrient intake, computed tomography (CT) scan, and plasma lipid profiles were assessed. Body fat percentage and body fat mass were significantly decreased following d-allulose supplementation. The high d-allulose group revealed a significant decrease in not only body mass index (BMI), but also total abdominal and subcutaneous fat areas measured by CT scans compared to the placebo group. There were no significant differences in nutrient intake, plasma lipid profiles, markers of liver and kidney function, and major inflammation markers among groups. These results provide useful information on the dose-dependent effect of d-allulose for overweight/obese adult humans. Based on these results, the efficacy of d-allulose for body fat reduction needs to be validated using dual energy X-ray absorption.


Assuntos
Fármacos Antiobesidade/administração & dosagem , Frutose/administração & dosagem , Obesidade/tratamento farmacológico , Edulcorantes/administração & dosagem , Redução de Peso/efeitos dos fármacos , Gordura Abdominal/diagnóstico por imagem , Gordura Abdominal/efeitos dos fármacos , Gordura Abdominal/fisiopatologia , Adiposidade/efeitos dos fármacos , Adulto , Fármacos Antiobesidade/efeitos adversos , Biomarcadores/sangue , Glicemia/metabolismo , Índice de Massa Corporal , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Frutose/efeitos adversos , Humanos , Mediadores da Inflamação/sangue , Lipídeos/sangue , Masculino , Obesidade/sangue , Obesidade/diagnóstico , Obesidade/fisiopatologia , Dados Preliminares , República da Coreia , Gordura Subcutânea/diagnóstico por imagem , Gordura Subcutânea/efeitos dos fármacos , Gordura Subcutânea/fisiopatologia , Edulcorantes/efeitos adversos , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
20.
Biotechnol Lett ; 40(1): 197-204, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29064007

RESUMO

OBJECTIVE: To purify and characterize a specific enzyme from a commercial pectinase for the production of steviol from stevioside (Ste) without adding organic solvent and to improve steviol production. RESULTS: Commercial Sumizyme PX converted Ste to steviol with a yield of 98%. ß-Glucosidase from Sumizyme PX (ßglyPX) was purified in three steps with 12.5-fold purification and 51% yield. The specific activity of the purified ßglyPX was 141 U/mg. The molecular weight of ßglyPX was ~ 116 kDa on SDS-PAGE. Its optimum activity was at pH 3.5 and 65 °C. It was stable for 12 h up to 55 °C and for 24 h at pH 2-9.5. K m values of ßglyPX for pNPGal, oNPGlc, lactose, and Ste were 2.4, 0.7, 18, and 7.8 mM, respectively. The optimum conditions for steviol production were 55 °C, 900 U/ml, 80 mg Ste/ml, 12 h. CONCLUSION: ßglyPX contains great potential for industrial steviol production from Ste.


Assuntos
Diterpenos do Tipo Caurano/isolamento & purificação , Diterpenos do Tipo Caurano/metabolismo , Glucosídeos/metabolismo , Poligalacturonase/metabolismo , beta-Glucosidase/isolamento & purificação , beta-Glucosidase/metabolismo , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Peso Molecular , Temperatura , beta-Glucosidase/química
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