Hyun Ju You

Bifidobacterium bifidum BGN4 is a probiotic strain that has been used as a major ingredient to produce nutraceutical products and as a dairy starter since 2000. The various bio-functional effects and potential for industrial application of B. bifidum BGN4 has been characterized and proven by in vitro (i.e., phytochemical bio-catalysis, cell adhesion and anti-carcinogenic effects on cell lines, and immunomodulatory effects on immune cells), in vivo (i.e., suppressed allergic responses in mouse mo

The flavonol quercetin in plants and foods occurs predominantly in the form of glycoside whose sugar moiety affects the bioavailability and the mechanism of its biological activities. The antiproliferative activities of quercetin derivatives such as quercetin aglycone, quercetin-3-β-D-glucoside (Q3G), and rutin were compared using six different cancer cell lines including colon, breast, hepatocellular, and lung cancer. The IC50 value of Q3G ranged between 15 and 25 μM in HT-29, HCT 116, MCF-7, H

Phytochemicals provide environmentally friendly and relatively inexpensive natural products, which could potentially benefit public health by controlling human norovirus (HuNoV) infection. In this study, 18 different phytochemicals were evaluated for antiviral effects against norovirus using murine norovirus (MNV) as a model for norovirus biology. Among these phytochemicals, curcumin (CCM) was the most potent anti-noroviral phytochemical, followed by resveratrol (RVT). In a cell culture infectio

Strains of bifidobacteria have many health-promotion effects. Whole cells or cytoplasm extracts of Bifidobacterium bifidum BGN4, isolated from human feces, inhibited the growth of several cancer cell lines. The polysaccharide fraction (BB-pol) extracted from B. bifidum BGN4 had a novel composition, comprising chiroinositol, rhamnose, glucose, galactose, and ribose. Three human colon cancer cell lines were treated with BB-pol: HT-29, HCT-116, and Caco-2. Trypan blue exclusion assay and BrdU incor

Despite some evidence supporting an association between decreased Mg²⁺ levels and depression from studies with serum, the results of our meta-analysis urge to use caution when associating Mg²⁺ levels and depression. Future studies are needed to establish a consensus for the role of low Mg²⁺ levels in depression.

Selenium and zinc are essential trace minerals for humans with various biological functions. In this study, selenium- and zinc-tolerant lactic acid bacteria (LAB) isolates were screened out from human fecal samples. Amongst three hundred LAB isolates, the <i>Lactobacillus plantarum</i> SeZi strain displayed the tolerance against selenium and zinc with the greatest biomass production and bioaccumulation of selenium and zinc. To further assess the characteristics of this strain, the lyophilized <i

In spite of the reported probiotic effects, Bifidobacterium bifidum BGN4 (BGN4) showed no β- glucosidase activity and failed to biotransform isoflavone glucosides into the more bioactive aglycones during soy milk fermentation. To develop an isoflavone-biotransforming BGN4, we constructed the recombinant B. bifidum BGN4 strain (B919G) by cloning the structural β- glucosidase gene from B. lactis AD011 (AD011) using the expression vector with the constitutively active promoter 919 from BGN4. As a r

<i>Helicobacter pylori</i> infection is the most common cause of gastritis and gastric ulcers. Considering the severe side effects of current antibiotic therapies, it is crucial to find an alternate treatment for <i>H. pylori</i> infection. In this study, we investigated the anti-<i>H. pylori</i> effects of a newly isolated strain of <i>Lactobacillus plantarum</i> (pH3A), monolaurin, grapefruit seed extract (GSE), and their synergies <i>in vitro</i> and <i>in vivo</i>. Monolaurin and GSE suppres

The cocktails of antibiotics are utilized to study the functions of microbiota. There have been studies on the alteration of not only the microbiota composition but also the host's metabolism or immunity. However, the bacterial species associated with these altered physiologic markers are still unclear. Therefore, we supplied mice with drinking water containing ampicillin (AMP), vancomycin (VAN), neomycin (NEO), or metronidazole (MET) to observe the effect of each antibiotic on helper T cells an

Lactobacilli have been widely used as probiotics because of their benefits for intestinal health and physiological functions. Among a variety of <i>Lactobacillus</i> genera, <i>Limosilactobacillus reuteri</i> has been studied for its ability to exert anti-inflammatory functions and its role in controlling metabolic disorders, as well as the production of the antimicrobial compound reuterin. However, the effects and mechanisms of <i>L. reuteri</i> on enhancing immune responses in the immunosuppre