Joong-Hyuck Auh

Cryopreservation in trehalose preserves functional capacity of murine spermatogonial stem cells.

Development of techniques to isolate, culture, and transplant human spermatogonial stem cells (SSCs) has the future potential to treat male infertility. To maximize the efficiency of these techniques, methods for SSC cryopreservation need to be developed to bank SSCs for extended periods of time. Although, it has been demonstrated that SSCs can reinitiate spermatogenesis after freezing, optimal cryopreservation protocols that maximize SSC proliferative capacity post-thaw have not been identified. The objective of this study was to develop an efficient cryopreservation technique for preservation of SSCs. To identify efficient cryopreservation methods for long-term preservation of SSCs, isolated testis cells enriched for SSCs were placed in medium containing dimethyl sulfoxide (DMSO) or DMSO and trehalose (50 mM, 100 mM, or 200 mM), and frozen in liquid nitrogen for 1 week, 1 month, or 3 months. Freezing in 50 mM trehalose resulted in significantly higher cell viability compared to DMSO at all thawing times and a higher proliferation rate compared to DMSO for the 1 week freezing period. Freezing in 200 mM trehalose did not result in increased cell viability; however, proliferation activity was significantly higher and percentage of apoptotic cells was significantly lower compared to DMSO after freezing for 1 and 3 months. To confirm the functionality of SSCs frozen in 200 mM trehalose, SSC transplantation was performed. Donor SSCs formed spermatogenic colonies and sperm capable of generating normal progeny. Collectively, these results indicate that freezing in DMSO with 200 mM trehalose serves as an efficient method for the cryopreservation of SSCs.

Classification of fermented soybean paste during fermentation by 1H nuclear magnetic resonance spectroscopy and principal component analysis.

Fermented soybean paste (doenjang, FSP) is a traditionally fermented Korean food produced by fermentation with various microorganisms that is known to exhibit various beneficial bioactivities. To investigate the changes in nonvolatile metabolites of FSP during fermentation, samples produced with six fermentation times were analyzed using an 1H nuclear magnetic resonance spectroscopy (NMR)-based metabolomics technique. This revealed clear separation of 50% methanol extracts of the FSP samples with different fermentation times in the principal component plots by combining PC1 and PC2, which cumulatively accounted for 94.2% of the variance. Major compounds contributing to the separation of 50% methanol extracts of FSP with various fermentation times were isoleucine/leucine, lactate, alanine, acetic acid, glutamine, choline, tyrosine, and phenylalanine. In addition, the 1H NMR spectra of chloroform extracts were separated mainly by a combination of PC1 and PC3, which accounted for 72.6% of the variance. The present study suggests the usefulness of a 1H NMR-based metabolomics approach to discriminate FSP samples subjected to different fermentation times, and this is the first report regarding metabolomic profiling of FSP.

Metabolomic Analysis Reveals Cyanidins in Black Raspberry as Candidates for Suppression of Lipopolysaccharide-Induced Inflammation in Murine Macrophages

The extracts produced by multisolvent extraction and subfractionation with preparative liquid chromatography of black raspberry (Rubus coreanus Miquel) cultivated in Gochang, South Korea, were tested for their anti-inflammatory effects. The metabolomic profiling and analysis by orthogonal partial least-squares discriminant analysis (OLPS-DA) suggested that cyanidin, cyanidin-3-glucoside (C3G), and cyanidin-3-rutinoside (C3R) were key components for the anti-inflammatory responses in the most active fraction BF3-1, where they were present at 0.44, 1.26, and 0.56 μg/mg of BF3-1, respectively. Both BF3-1 and mixture of these cyanidins at the same ratio reduced lipopolysaccharide (LPS)-induced protein level of iNOS expression and suppressed mRNA and protein expressions of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β through inhibiting the phosphorylation of mitogen-activated protein kinases (MAPKs) and STAT3 in murine macrophage RAW264.7 cells. Overall, the results suggested that co-administration of cyanidin, C3G, and C3R is more effective than that of cyanidin alone and that the coexistence of these anthocyanin components in black raspberry plays a vital role in regulating LPS-induced inflammation even at submicromolar concentrations, making it possible to explain the health beneficial activity of its extracts.

In vitro α-glucosidase and pancreatic lipase inhibitory activities and antioxidants of Samnamul (Aruncus dioicus) during rehydration and cooking

In vitro α-glucosidase and pancreatic lipase inhibitory activities of ethanol extracts of samnamul (dried young shoots of Aruncus dioicus) during rehydration (soaking, 30 min boiling, and re-soaking in water) and subsequent cooking at 180°C with/without perilla oil were determined for evaluation of its anti-diabetic and antiobesity potential. Polyphenol and flavonoid contents were monitored by spectrophotometry. Rehydration and boiling of samnamul reduced α-glucosidase and pancreatic lipase inhibitory activities as well as polyphenol and flavonoid contents, whereas soaking time did not have a significant effect. Of the rehydration and cooking processes, 30 min boiling was the most critical in reducing anti-diabetic and anti-obesity activities as well as antioxidant contents. Perilla oil addition improved α-glucosidase inhibitory activity, possibly through polyphenol addition. These results suggest that dietary intake of samnamul can reduce the risks of diabetes and obesity, and perilla oil can additionally improve its health benefits.

Supplementation of Alkaline Phytase (Ds11) in Whole-Wheat Bread Reduces Phytate Content and Improves Mineral Solubility

In this study, alkaline phytase was added to whole-wheat bread and the phytate content and mineral profiles were compared to commercially available acidic phytase. At neutral pH, some phytate (approximately 20%) was degraded by endogenous phytase in wheat flour, while 40% of phytate was hydrolyzed by alkaline phytase DS11 and a 35% reduction was observed with acidic phytase. Most of the enzymatic activity occurred during the proofing stage, and the rate of reaction depended on pH. DS11 phytase effectively degraded the phytate level within a 30 min treatment at pH 7; however, at least 60 min was needed with acidic phytase to achieve the same hydrolysis level. Mineral profiles were also dramatically affected by the phytate reduction. The biggest increase was observed in Fe²⁺ by the phytase treatment. The Fe²⁺ content increased 10-fold at pH 7 and 8-fold at pH 5 with alkaline phytase DS11. Alkaline phytase DS11 was shown to be effective at phytate reduction in whole-wheat bread preparation. Additionally, phytate degradation enhanced the mineral availability of bread.

Pinoresinol diglucoside is screened as a putative α-glucosidase inhibiting compound in Actinidia arguta leaves

Actinidia arguta leaves are consumed as a popular food material in Korea and have been reported to exert beneficial effects on humans due to its constituent polyphenolic compounds. In this study, the α-glucosidase inhibitory compounds in A. arguta were screened and identified through α-glucosidase-guided fractionation and metabolomic analysis. The 50% ethanol extracts of A. arguta showed strong inhibitory effect (32.6%), which was comparable to acarbose as a positive control (30.0%). Through multiple steps of fractionation, pinoresinol diglucoside and fertaric acid were identified as the major potent compounds in A. arguta inhibiting α-glucosidase activity by liquid chromatography mass spectrometry analysis and metabolomic comparison. Particularly, because pinoresinol and its glycosides have been demonstrated as α-glucosidase inhibitory agents, pinoresinol diglucoside was proposed to be a putative key compound for α-glucosidase inhibition in A. arguta. This is the first study demonstrating the anti-diabetic effect of a pinoresinol-containing fraction of A. arguta and would be useful for its application as a natural α-glucosidase inhibitor.

Differentiation of highbush blueberry (Vaccinium corymbosum L.) fruit cultivars by GC–MS-based metabolic profiling

Highbush blueberries (Vaccinium corymbosum L.) are cultivated worldwide for their fruit with unique taste and potential health benefits. Blueray, Bluecrop, and Spartan are prominent among the various blueberry cultivars. We performed gas chromatography–mass spectrometry (GC–MS)-based metabolic profiling to differentiate the fruits of these three cultivars, and built an optimal partial least squares-discriminant analysis (PLS-DA) model to separate them. Amino acids, fatty acids, organic acids, phenolic compounds, and sugars were identified in the fruits. The optimized PLS-DA model for different cultivars of the fruits was obtained by selecting variables based on a variable importance in the projection (VIP) cut-off value of 1.0. Caffeic acid, aspartic acid, acetic acid, threonolactone, inositol, xylose, glucoside, linolenic acid, mannose, altrose, glycine alanine, and valine were found to be relevant and contributing compounds for differentiating cultivars. In addition, a hierarchical cluster analyses dendrogram pattern was correlated with the PLS-DA. This study suggested that GC–MS-based metabolic profiling coupled with multivariate statistical analysis could be used to differentiate the fruits of three major highbush blueberry cultivars.

Erratum to: Differentiation of black raspberry fruits according to species and geographic origins by genomic analysis and 1H-NMR-based metabolic profilin

Random amplification of polymorphic DNA (RAPD) and NMR techniques were used to differentiate and identify species of black raspberry (BR) of different geographic origins. BR leaf samples from five geographic origins were identified as Rubus japonicus and R. coreanus by RAPD. 1H-NMR analysis was also performed for BR fruit extracts from different geographic origins. Major compounds assigned in 1H-NMR spectra of BR fruits were amino acids, organic acids, sugars, phenolic acids, and purine derivatives. In addition, relative levels of total phenolic compounds, flavanols, flavonoids, and anthocyanins in the BR fruits were further analyzed. Hierarchical cluster analyses (HCA) based on the genetic (RAPD of leaf samples) and metabolic (1HNMR, total phenolic compounds, flavanols, flavonoids and anthocyanins of fruit samples) datasets were independently performed. The HCA dendrogram pattern derived from RAPD genetic fingerprinting of BR leaf samples matched that from the 1H-NMR data of BR fruit samples. This research demonstrates that metabolic profiling of BR fruit based on 1H-NMR is a promising method for differentiating BR fruits of various species and geographic origins.

Sulforaphane inhibited tumor necrosis factor-α induced migration and invasion in estrogen receptor negative human breast cancer cells

Sulforaphane significantly (p<0.05) inhibited tumor necrosis factor (TNF)-α induced cellular migration and invasion in MCF10DCIS.com human breast cancer cells, compared with controls. mRNA and protein expressions of MMPs, including MMP-2, MMP-9, and MMP-13, and the enzymatic activities of MMP-2 and MMP-9 were suppressed by sulforaphane treatments at 1, 5, and 10 μM concentration in MCF10DCIS.com cells. Sulforaphane should be considered as a potent agent for retardation of mammary tumorigenesis.

Optimizing Carnosine Containing Extract Preparation from Chicken Breast for Anti-glycating agents.

Optimization of carnosine and anserine extraction from chicken breast was performed using response surface methodology (RSM) to obtain the maximized physiological activities for anti-glycation and anti-oxidation. The optimum extraction conditions were water extraction for 1.6 h in the case of the 20-wk laying hen muscle and water extraction for 2.12 h in the case of 90-wk laying hen muscle. Higher carnosine and anserine contents were measured in the 20-wk laying hen muscle, along with higher physiological activities, which increased in direct proportion with the dipeptide contents. The extracts prepared from the 20-wk laying hen under optimum conditions showed 57% inhibition of advanced glycated end-product formation, 64% inhibition of lipid peroxidation, and 61% of DPPH radical scavenging effects. On the other hand, 52% inhibition of AGE formation, 62% inhibition of lipid peroxidation, and 53% of DPPH radical scavenging effect were demonstrated within the 90-wk laying hen. In addition, the ratio of carnosine was a key indicator for the physiological activities of the extracts.