• FOCUS: LIFE SCIENCE
• /
• 제1호
• /
• pp.1.1-1.4
• /
• 2024

This article provides comprehensive guidance on the maintenance, cleaning, regeneration, and storage of silica-based HPLC (High-Performance Liquid Chromatography) columns. The general considerations emphasize the importance of using in-line filters and guard cartridges to protect columns from blockage and irreversible sample adsorption. While these measures help, contamination by strongly adsorbed sample components can still occur over time, leading to an increase in back pressure, loss of efficiency, and other issues. To maximize column lifetime, especially with UHPLC (Ultra-High Performance Liquid Chromatography) columns, it is advisable to use ultra-pure solvents, freshly prepared aqueous mobile phases, and to filter all samples, standards, and mobile phases. Additionally, an in-line filter system and sample clean-up on dirty samples are recommended. However, in cases of irreversible compound adsorption or column voiding, regeneration may not be possible. The document also provides specific recommendations for column cleaning procedures, including the flushing procedures for various types of columns such as reversed phase, unbonded silica, bonded normal phase, anion exchange, cation exchange, and size exclusion columns for proteins. The flushing procedures involve using specific solvents in a series to clean and regenerate the columns. It is emphasized that the flow rate during flushing should not exceed the specified limit for the particular column, and the last solvent used should be compatible with the mobile phase. Furthermore, the article outlines the storage conditions for silica based HPLC columns, highlighting the impact of storage conditions on the column's lifetime. It is recommended to flush all buffers, salts, and ion-pairing reagents from the column before storage. The storage solvent should ideally match the one used in the initial column test chromatogram provided by the manufacturer, and column end plugs should be fitted to prevent solvent evaporation and drying out of the packing bed.

• Journal of Microbiology and Biotechnology
• /
• 제26권1호
• /
• pp.61-65
• /
• 2016

From the lees of bokbunja wine (LBW) made from Rubus coreanus Miquel, we have identified six compounds (1: trans-4-hydroxycinnamic acid; 2: trans-4-hydroxy-3-methoxycinnamic acid; 3: 3,4-dihydroxycinnamic acid; 4: 4-hydroxy-3-methoxybenzoic acid; 5: 3,5-dimethoxy-4-hydroxybenzoic acid; and 6: 3,5-dimethoxy-4-hydroxycinnamic acid (sinapic acid)) through silica gel chromatography and UHPLC-MS. The compounds 1-6 showed strong anticoagulation and platelet aggregation inhibitory activities without hemolytic effect against human red blood cells. To date, this is the first report of the in vitro anti-thrombosis activity of sinapic acid. Our results suggest that different cinnamic and benzoic acid derivatives are closely linked to the anti-thrombosis activity of LBW, and sinapic acid could be developed as a promising anti-thrombosis agent.

• 한국식품영양학회지
• /
• 제29권1호
• /
• pp.73-78
• /
• 2016

Propolis possesses antimicrobial, anti-inflammatory, anaesthetic and immunostimulating activities. The aim of this study was to evaluated chemical composition and in vitro anti-Helicobacter pylori activity of eight propolis ethanolic extracts form different region in Korea. The chemical composition of eight Korean propolis was investicated by absorption spectrophotomety and UHPLC. Total penolic and total flavonoids content ranged between $21{\pm}1.5$ and $31{\pm}1.8$ gallic acid g/100 g and $7.2{\pm}0.9$ and $24.4{\pm}1.9$ quercetin g/100 g, respectively. The p-coumaric acid as standard components content ranged between $0.29{\pm}0.00$ and $2.34{\pm}0.02mg/g$ using UHPLC. Cinnamic acid content between $0.43{\pm}0.00$ and $1.33{\pm}0.01mg/g$. 80% ethanolic extract of propolis against H. pylori was evaluated by using the disc diffusion method. Ethanol was used as a control. Mean diameters of H. pylori growth inhibition using $10{\mu}g/mL$, $50{\mu}g/mL$ or $100{\mu}g/mL$ ethanol propolis per disc were 0, ranging from 0.9 to 2.1 mm and from 1.9 to 3.5 mm, respectively. In conclusion, variation in the chemical composition of Korean propolis were mainly due to the difference in the preferred regional plants visited by honeybees. Also Korean propolis possesses considerable antibacterial activity against H. pylori. There was not confirmed a correlation between the chemical composion contens and anti-H. pylori effect. The potential of propolis in the prevention or treatment of H. pylori infection is worth further extensive evaluation.

• Mass Spectrometry Letters
• /
• 제11권4호
• /
• pp.82-89
• /
• 2020

A systematic isolation and characterization study for Cassia auriculata (CA) seeds resulted in identifying antidiabetic compounds 1,3,8-trihydroxyanthraquinone and quercetin, quercetin-3-O-rutinoside, gallic acid, caffeic acid, ferulic acid, and ellagic acid. The ultra-high-performance liquid chromatography based triple quadrupole mass spectrometry methodology was developed and validated for simultaneous identification and confirmation of these compounds from CA seeds. Multiple reaction monitoring (MRM) based quantification method was developed with MRM optimizer software for MS1 and MS2 mass analysis. The method was optimized on precursor ions and product ions with the ion ratio of each compound. The calibration curves of seven bioactive analytes showed excellent linearity (r2 ≥ 0.99). The quantitation results found precise (RSD, < 10 %) with good recoveries (84.58 to 101.42%). The matrix effect and extraction recoveries were found within the range (91.66 to 102.11%) for the CA seeds. This is the first MS/MS-based methodology applied to quantifying seven antidiabetic compounds in CA seeds and its extract for quality control purposes.

• 한국입자에어로졸학회지
• /
• 제18권2호
• /
• pp.37-50
• /
• 2022

Due to the syndrome coronavirus 2 (SARS-CoV-2) pandemic, the subway passenger cabin should be continuously sterilized. However, a disinfectant such as chlorine is toxic and can lead to different issues to human health. In this paper, we introduced a novel disinfectant based on natural product (Dendropanax morbifera extract). Via ultra-high performance liquid chromatography - mass spectrometer (UHPLC-MS), different compounds from Dendropanax morbifera extract showed antivirus potentials. Antimicrobial experiments confirmed that the air-disinfectant containing Dendropanax morbifera can eliminate harmful microorganisms including Gram (-), Gram (+), and yeast within 5 mins. The as-prepared air-disinfectant also showed high antivirus activity against H1N1, HRV, and EV71. Deodorization test also indicates that the as-prepared air-disinfectant can lower the harmful gas such as ammonia and trimethylamine in the atmosphere. To evaluate the potential of air-disinfectant containing Dendropanax morbifera in practical applications, different safety tests including acute oral toxicity, acute skin irritation, and eye irritation were conducted. Results showed that the as-prepared disinfectant did not negatively affect tested animals during these safety investigations.

• Journal of Plant Biotechnology
• /
• 제49권3호
• /
• pp.257-270
• /
• 2022

The aim of this work was to prepare a new biodegradable polyhydroxybutyrate (PHB) submicron fiber mat loaded with hypericin-rich Hypericum perforatum raw extract by centrifugal spinning technology, an alternative approach to the traditional method of electrospinning to fabricate nanofibers or microfibers from solutions at high speed and low cost. Hypericins in methanol/acetone extract of H. perforatum were determined by UHPLC-MS/MS and HPLC/PDA. Submicron fiber mats composed of pure PHB or PHB enriched with H. perforatum extract were prepared using a pilot plant demonstrator for the centrifugal spinning technology and characterized by SEM. Singlet oxygen production was quantified by the 1,3-diphenylisobenzofuran (DPIBF) method in hexane. The results proved a significant production of singlet oxygen by the prepared submicron fiber mat. We also found a significant antibacterial activity against the bacterial strain Escherichia coli CCM 5417 by a method in accordance with JIS Z 2801/ISO 22196 standards. The H. perforatum extract-enriched PHB submicron fiber mats showed potential for the development of self-cleaning and antimicrobial air filters.

• Journal of Microbiology and Biotechnology
• /
• 제33권10호
• /
• pp.1317-1328
• /
• 2023

Green tea (GT) polyphenols undergo extensive metabolism within gastrointestinal tract (GIT), where their derivatives compounds potentially modulate the gut microbiome. This biotransformation process involves a cascade of exclusive gut microbial enzymes which chemically modify the GT polyphenols influencing both their bioactivity and bioavailability in host. Herein, we examined the in vitro interactions between 37 different human gut microbiota and the GT polyphenols. UHPLC-LTQ-Orbitrap-MS/MS analysis of the culture broth extracts unravel that genera Adlercreutzia, Eggerthella and Lactiplantibacillus plantarum KACC11451 promoted C-ring opening reaction in GT catechins. In addition, L. plantarum also hydrolyzed catechin galloyl esters to produce gallic acid and pyrogallol, and also converted flavonoid glycosides to their aglycone derivatives. Biotransformation of GT polyphenols into derivative compounds enhanced their antioxidant bioactivities in culture broth extracts. Considering the effects of GT polyphenols on specific growth rates of gut bacteria, we noted that GT polyphenols and their derivate compounds inhibited most species in phylum Actinobacteria, Bacteroides, and Firmicutes except genus Lactobacillus. The present study delineates the likely mechanisms involved in the metabolism and bioavailability of GT polyphenols upon exposure to gut microbiota. Further, widening this workflow to understand the metabolism of various other dietary polyphenols can unravel their biotransformation mechanisms and associated functions in human GIT.

• Journal of Applied Biological Chemistry
• /
• 제66권
• /
• pp.1-6
• /
• 2023

Dendranthema zawadskii is a one of the popular plants as native in South Korea. In this study, linarin was isolated and purified using silica-gel, Diaion, and Sephadex LH-20 from the aerial parts of D. zawadskii. The chemical structure was completely identified through spectroscopic data including 1D, 2D nucleic magnetic resonance, and HRFABMS. Furthermore, linarin inhibited the bacterial neuraminidase (BNA) activity with 13.5 μM of IC₅₀ dose-dependently. Through the enzyme kinetic experiments, linarin as BNA inhibitor exhibited a typical noncompetitive inhibition mode which K_m was contestant and V_max decreased as the concentration of the inhibitor increased. It was further identified that the inhibition constant was 16.0 μM. Linarin was the most abundance metabolite in the aerial part of D. zawadskii extract by UHPLC-TOF/MS analysis. Therefore, D. zawadskii and its main component are expected that it can be effectively used for the infection and inflammation caused by bacteria.

• ALGAE
• /
• 제35권2호
• /
• pp.177-187
• /
• 2020

Cyanobacteria have been widely reported to produce a variety of UV-absorbing mycosporine-like amino acids (MAAs). Herein, we reported production of the unusual MAA, mycosporine-glycine-alanine (MGA) in the cyanobacterium Sphaerospermopsis torques-reginae ITEP-024 using a newly developed UHPLC-DAD-MS/HRMS (ultra-high performance liquid chromatography-diode array detection-high resolution tandem mass spectrometry) method. MGA had previously been first identified in a red-algae, but S. torques-reginae strain ITEP-024 is the first cyanobacteria to be reported as an MGA producer. Herein, the chemical structure of MGA is fully elucidated from one-dimensional / two-dimensional nuclear magnetic resonance and HRMS data analyses. MAAs are unusually produced constitutively in S. torques-reginae ITEP-024, and this production was further enhanced following UV-irradiance. It has been proposed that MAA biosynthesis proceeds in cyanobacteria from the pentose phosphate pathway intermediate sedoheptulose 7-phosphate. Annotation of a gene cluster encoded in the genome sequence of S. torques-reginae ITEP-024 supports these gene products could catalyse the biosynthesis of MAAs. However, addition of glyphosate to cultures of S. torques-reginae ITEP-024 abolished constitutive and ultra-violet radiation induced production of MGA, shinorine and porphyra-334. This finding supports involvement of the shikimic acid pathway in the biosynthesis of MAAs by this species.

• Journal of Ginseng Research
• /
• 제41권1호
• /
• pp.10-22
• /
• 2017

Background: Asian ginseng and American ginseng are functional foods that share a close genetic relationship and are well-known worldwide. This article aims to investigate the correlation between morphological characteristics and the inherent quality of Asian and American ginsengs. Methods: In this study, an ultra-HPLC-quadrupole/time-of-flight MS (UHPLC-Q/TOF-MS) method was established for the quantitative analysis of 45 ginseng samples. The method developed for determination was precise and accurate. Results: The results showed that Asian ginseng samples with the same growing time (with the same or similar number of stem scars) that had a thinner main root, a longer rhizome and more branch roots contained greater amounts of ginsenosides. For American ginseng, two tendencies were observed in the relationship between the diameter of the main root and contents of ginsenosides. One tendency was that samples with thinner main roots tended to contain higher levels of ginsenosides, which was observed in the samples sold under the commercial name pao-shen. Another tendency was that samples with thicker main roots contained higher contents of ginsenosides, which was observed in the samples sold under the commercial name pao-mian, as well as in samples of American ginseng cultivated in Jilin, China. Conclusion: An approach using ultra-HPLC-quadrupole/time-of-flight MS was successfully established to link morphology and active components for evaluating the quality of Asian and American ginsengs. Clear correlation between visible morphological features and quality of Asian and American ginsengs was found. People can see the difference; this means consumers and vendors can evaluate ginseng by themselves.