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The chemical composition of ginseng varies by several factors such as age, harvest season, and region. Each part of fresh ginseng contains certain valuable bioactive compounds; however, chemical studies of ginseng have focused on the ginsenoside content. In this study, we examine the chemical composition of Panax ginseng Meyer as related to harvest season and specific root parts via untargeted metabolomics using ultra-high performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry (UPLC-QTOF-MS). Multivariate statistical analysis such as partial least squares discriminant analysis (PLS-DA) was used to select significant metabolites distinguishing ginseng harvested in different seasons and various ginseng parts. The selected thirteen metabolites were identified as amino acids, ginsenosides, and fatty acid amides through MS fragment pattern analysis. Additional chemometric analysis revealed chemical consistency between main and fine roots regardless of harvest time, indicating a stable chemical composition in P. ginseng among seasons. Furthermore, most ginsenosides among the thirteen selected metabolites had higher abundance in fine roots than in main roots, while primary metabolites were more abundant in main roots, highlighting a unique chemical composition dependent on the specific root parts. [ABSTRACT FROM AUTHOR]

Author(s): Jinbong Hwang [sup.1], Ji-Su Park [sup.1], So Young Kim [sup.1], Nho-Eul Song [sup.1], Miyoung Yoo [sup.1], Youngmin Choi [sup.2], Jin-Sik Nam [sup.3], Dongwon Seo [sup.1] Author Affiliations: (1) grid.418974.7, [...], In this study, the determination of iodine in 123 different types of foods was conducted. Iodine-selective electrode, microwave digestion/inductively coupled plasma mass spectrometry and tetramethylammonium hydroxide extraction/ inductively coupled plasma mass spectrometry (TMAH/ICP-MS) methods were tested to achieve the highest recoveries for the determination of iodine. Among them, TMAH/ICP-MS method was the most effective with respect to analytical recoveries (90-99%), limits of detection (0.013 [micro]g/kg) and quantification (0.04 [micro]g/kg) values. The intra- and inter-day relative standard deviations for iodine SRM were

Recent assessments of the correlations between food and medicine underscore the importance of functional foods in disease prevention and management. Functional foods offer health benefits beyond basic nutrition, with fresh fruits and vegetables being particularly prominent because of their rich polyphenol content. In this study, we elucidated the phytochemicals in ice plant (Mesembryanthemum crystallinum), a globally consumed vegetable, using an LC-QTOF/MS-based untargeted detection method. The phytochemicals were clustered based on their structural similarity using molecular networking and annotated using the in silico tool for network annotation propagation. To identify the bioactive compounds, eight compounds were isolated from ice plant extracts. These compounds were identified using extensive spectroscopic methods, including 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. Additionally, we evaluated the antioxidant and anti-inflammatory activities of all the isolates. Among the tested compounds, three showed antioxidant activity and all eight showed anti-inflammatory activity, demonstrating the potential of ice plant as a functional food. [ABSTRACT FROM AUTHOR]

Efficient utilization of galactose by microorganisms can lead to the production of valuable bio-products and improved metabolic processes. While Bacillus subtilis has inherent pathways for galactose metabolism, there is potential for enhancement via evolutionary strategies. This study aimed to boost galactose utilization in B. subtilis using adaptive laboratory evolution (ALE) and to elucidate the genetic and metabolic changes underlying the observed enhancements. The strains of B. subtilis underwent multiple rounds of adaptive laboratory evolution (approximately 5000 generations) in an environment that favored the use of galactose. This process resulted in an enhanced specific growth rate of 0.319 ± 0.005 h−1, a significant increase from the 0.03 ± 0.008 h−1 observed in the wild-type strains. Upon selecting the evolved strain BSGA14, a comprehensive whole-genome sequencing revealed the presence of 63 single nucleotide polymorphisms (SNPs). Two of them, located in the coding sequences of the genes araR and glcR, were found to be the advantageous mutations after reverse engineering. The strain with these two accumulated mutations, BSGALE4, exhibited similar specific growth rate on galactose to the evolved strain BSGA14 (0.296 ± 0.01 h−1). Furthermore, evolved strain showed higher productivity of protease and β-galactosidase in mock soybean biomass medium. ALE proved to be a potent tool for enhancing galactose metabolism in B. subtilis. The findings offer valuable insights into the potential of evolutionary strategies in microbial engineering and pave the way for industrial applications harnessing enhanced galactose conversion. Key Points: Following adaptive laboratory evolution in a minimal medium with galactose serving as the selective pressure, the B. subtilis BSGA14 strain was successfully developed, exhibiting a specific growth rate of 0.319 ± 0.005 h−1. Among SNPs after resequencing, mutation in the araR gene enhances the uptake of galactose in Bacillus subtilis, leading to increased galactose utilization. The nonsense mutation in the glcR gene, which is involved in carbon catabolite repression (CCR) and sugar phosphorylation, influences galactose metabolism in B. subtilis. [ABSTRACT FROM AUTHOR]

In order to improve the slow ethanol fermentation during acetic acid fermentation process of black raspberry vinegar (BRV), the microbiological and physicochemical aspects of the effects of indigenous Saccharomyces cerevisiae JBCC-21A were examined. The selected S. cerevisiae JBCC-21A showed better growth and ethanol production rates than the commercial yeast strains. The ethanol production rate was 3-times faster than the traditional method. Acetic acid fermentation by S. cerevisiae JBCC-21A began 10 days earlier than the traditional method and reached up to 60 g/L acetic acid. Bacterial counts revealed Acetobacter pasteurianus was the only dominant species throughout the inoculated acetic acid fermentation. The physicochemical and functional properties of the fermented vinegar using indigenous S. cerevisiae JBCC-21A maintained a high quality similar to the traditional method, while being the faster fermentation process. Thus, it is suggested that inoculation of the indigenous S. cerevisiae strain in order to shorten the fermentation time without affecting the quality of traditional BRV. [ABSTRACT FROM AUTHOR]

This study examined the efficient production and optimal separation procedures for pure L-threo-3,4-dihydroxyphenylserine (L-threo-DOPS) from a mixture of diastereomers synthesized by whole-cell aldol condensation reaction, harboring diastereoselectivity-enhanced L-threonine aldolase in Escherichia coli JM109. The addition of the reducing agent sodium sulfite was found to stimulate the production of L-threo-DOPS without affecting the diastereoselectivity ratio, especially at the 50 mM concentration. The optimal pH for diastereoselective synthesis was 6.5. The addition of Triton X-100 also strongly affected the synthesis yield, showing the highest conversion yield at a 0.75% concentration; however, the diastereoselectivity of the L-threonine aldolase was not affected. Lowering the temperature to 10°C did not significantly affect the diastereoselectiviy without affecting the synthesis rate. At the optimized conditions, a mixture of L-threo-DOPS and L-erythro-DOPS was synthesized by diastereoselectivity-enhanced L-threonine aldolase from E. coli in a continuous process for 100 hr, yielding an average of 4.0 mg/mL of L-threo-DOPS and 60% diastereoselectivity (de), and was subjected to two steps of ion exchange chromatography. The optimum separation conditions for the resin and solvent were evaluated in which it was found that a two-step process with the ion-exchange resin Dowex 50 W × 8 and activated carbon by washing with 0.5 N acetic acid was sufficient to separate the L-threo-DOPS. By using two-step ion-exchange chromatography, synthesized high-purity L-threo-DOPS of up to 100% was purified with a yield of 71%. The remaining substrates, glycine and 3,4-dihydroxybenzaldehyde, were recovered successfully with a yield of 71.2%. Our results indicate this potential procedure as an economical purification process for the synthesis and purification of important L-threo-DOPS at the pharmaceutical level. [ABSTRACT FROM PUBLISHER]