Publications by authors named "Kyung Min Park"

120 Publications

Effects of freezing rate on structural changes in L-lactate dehydrogenase during the freezing process.

Sci Rep 2021 Jul 1;11(1):13643. Epub 2021 Jul 1.

Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, Republic of Korea.

Freezing is a common method for improving enzyme storage stability. During the freezing process, the freezing rate is an important parameter that can affect protein stability. However, there is limited information on the denaturation mechanisms and protein conformational changes associated with the freezing rate. In this study, the effects of freezing rate on activity loss and conformational changes in a model enzyme, L-lactate dehydrogenase, were evaluated. Enzyme solutions were frozen at various rates, from 0.2 to 70.6 °C/min, and ice seeding was conducted to reduce supercooling. The results demonstrated that fast freezing results in activity loss, structural changes, and aggregation. The residual activities at freezing rates of 0.2, 12.8, and 70.6 °C/min were 77.6 ± 0.9%, 64.1 ± 0.4%, and 44.8 ± 2.0%, respectively. As the freezing rate increased, the degree of dissociation and unfolding increased significantly, as determined using blue native-polyacrylamide gel electrophoresis and fluorescence spectroscopy. Moreover, a large number of amyloid aggregates were detected in samples frozen at a fast freezing rate (70.6 °C/min). The enzyme inactivation mechanism induced by fast freezing was proposed in terms of increased dehydration at the enzyme surface and an ice/unfroze solution interface, which could be helpful to establish a common understanding of enzyme inactivation during the freezing process.
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http://dx.doi.org/10.1038/s41598-021-93127-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8249661PMC
July 2021

Morphological Features and Cold-Response Gene Expression in Mesophilic Group and Psychrotolerant Group under Low Temperature.

Microorganisms 2021 Jun 9;9(6). Epub 2021 Jun 9.

Department of Food Analysis Center, Korea Research Institute, Wanju-gun 55365, Jeollabuk-do, Korea.

At low temperatures, psychrotolerant group strains exhibit a higher growth rate than mesophilic strains do. However, the different survival responses of the psychrotolerant strain (BCG) and the mesophilic strain (BCG) at low temperatures are unclear. We investigated the morphological and genomic features of BCG and BCG to characterize their growth strategies at low temperatures. At low temperatures, morphological changes were observed only in BCG. These morphological changes included the elongation of rod-shaped cells, whereas the cell shape in BCG was unchanged at the low temperature. A transcriptomic analysis revealed that both species exhibited different growth-related traits during low-temperature growth. The BCG strain induces fatty acid biosynthesis, sulfur assimilation, and methionine and cysteine biosynthesis as a survival mechanism in cold systems. Increases in energy metabolism and fatty acid biosynthesis in the mesophilic group strain might explain its ability to grow at low temperatures. Several pathways involved in carbohydrate mechanisms were downregulated to conserve the energy required for growth. Peptidoglycan biosynthesis was upregulated, implying that a change of gene expression in both RNA-Seq and RT-qPCR contributed to sustaining its growth and rod shape at low temperatures. These results improve our understanding of the growth response of the group, including psychrotolerant group strains, at low temperatures and provide information for improving bacterial inhibition strategies in the food industry.
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http://dx.doi.org/10.3390/microorganisms9061255DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8229767PMC
June 2021

Poly(amino ester)-Based Polymers for Gene and Drug Delivery Systems and Further Application toward Cell Culture System.

Macromol Biosci 2021 Aug 12;21(8):e2100106. Epub 2021 Jun 12.

School of Chemical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea.

Various synthetic polymers based on poly(amino ester) (PAE) are suggested as candidates for gene and drug delivery owing to their pH-responsiveness, which contributes to efficient delivery performance. PAE-based pH-responsive polymers are more biodegradable and hydrophilic than other types of pH-responsive polymers. The functionality of PAE-based polymers can be reinforced by using different chemical modifications to improve the efficiency of gene and drug delivery. Additionally, PAE-based polymers are used in many ways in the biomedical field, such as in transdermal delivery and stem cell culture systems. Here, the recent novel PAE-based polymers designed for gene and drug delivery systems along with their further applications toward adult stem cell culture systems are reviewed. The synthetic tactics are contemplated and pros and cons of each type of polymer are analyzed, and detailed examples of the different types are analyzed.
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http://dx.doi.org/10.1002/mabi.202100106DOI Listing
August 2021

Variables that prolong total operative time for robotic-assisted laparoscopic myomectomy: A 10-year tertiary hospital study in Korea.

Eur J Obstet Gynecol Reprod Biol 2021 Jul 4;262:62-67. Epub 2021 May 4.

Department of Obstetrics and Gynecology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea. Electronic address:

Study Objective: To identify factors that prolong total operative time (TOT) in robotic-assisted laparoscopic myomectomy (RALM).

Design: Retrospective cohort study.

Setting: Tertiary university hospital.

Patients: Women who underwent RALM between April 2009 and May 2019 conducted by a single high-volume gynecologic surgeon.

Interventions: Patients' demographic data and intraoperative records were obtained. The association between the perioperative characteristics and TOT was analyzed.

Measurements And Main Results: A total of 584 cases met the inclusion criteria, with a mean TOT of 231.6 ± 86.7 min. The mean patient age was 36.3 ± 5.5 years, and the patients had a mean of 4.2 ± 4.0 myomas. The dominant myoma had a mean diameter of 7.6 ± 2.6 cm. The mean total weight of the extracted myomas removed was 202.2 ± 152.6 g. From multiple regression analysis, the following perioperative factors were intimately associated with the TOT: ① body mass index, ② the number of myomas, ③ weight of total myomas, ④ location of dominant myoma, ⑤ type of da Vinci robot system, ⑥ endometrial cavity opening during the operation, ⑦ intraoperative blood loss, and ⑧ patient hospitalization period. The number of myoma was most closely related to the TOT, with an R value of 0.330. All of the above factors with the exception of the type of robot system and location of dominant myoma were related to the console time. Age, parity, history of previous abdominal surgery, surgical indication, diameter, and FIGO classification were not associated with the TOT.

Conclusion: With an accurate identification of the perioperative parameters above, we can improve the quality of RALM by counselling, selecting an appropriate patient selection, and preoperative planning.
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http://dx.doi.org/10.1016/j.ejogrb.2021.05.003DOI Listing
July 2021

Updates on Therapeutic Alternatives for Genitourinary Syndrome of Menopause: Hormonal and Non-Hormonal Managements.

J Menopausal Med 2021 Apr;27(1):1-7

Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.

Postmenopausal atrophic vaginitis, along with vasomotor symptoms and sleep disorders, is one of the most troublesome symptoms of menopause. However, many women do not manage this symptom properly due to insufficient knowledge of the symptoms or sexual embarrassment. With appropriate treatment, many postmenopausal women can experience relief from discomforts, including burning sensation or dryness of the vagina and dyspareunia. Topical lubricants and moisturizers, systemic and local estrogens, testosterones, intravaginal dehydroepiandrosterones (DHEAs), selective estrogen receptor modulators, and energy-based therapies are possible treatment modalities. Systemic and local estrogen therapies effectively treat genitourinary syndrome of menopause (GSM), but they are contraindicated in patients with breast cancer, for whom lubricants and moisturizers must be considered as the primary treatment. Intravaginal DHEA and ospemifene can be recommended for moderate to severe GSM; however, there is insufficient data on the use of intravaginal DHEA or ospemifene in patients with breast cancer, and further studies are needed. Energy-based devices such as vaginal laser therapy reportedly alleviate GSM symptoms; however, the U.S. Food and Drug Administration warning has recently been issued because of complications such as chronic pain and burning sensations of the vagina. To summarize, clinicians should provide appropriate individualized treatment options depending on women's past history, symptom severity, and chief complaints.
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http://dx.doi.org/10.6118/jmm.20034DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8102810PMC
April 2021

Erythorbyl fatty acid ester as a multi-functional food emulsifier: Enzymatic synthesis, chemical identification, and functional characterization of erythorbyl myristate.

Food Chem 2021 Aug 8;353:129459. Epub 2021 Mar 8.

Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul 08826, Republic of Korea; Center for Agricultural Microorganism and Enzyme, Seoul National University, Seoul 08826, Republic of Korea. Electronic address:

Erythorbyl myristate (EM), a potential multi-functional food emulsifier, was newly synthesized by immobilized lipase-catalyzed esterification between antioxidative erythorbic acid and antibacterial myristic acid. The yield and productivity of EM were 56.13 ± 2.51 mg EM/g myristic acid and 1.76 ± 0.08 mM/h, respectively. The molecular structure of EM was identified as (R)-2-((R)-3,4-dihydroxy-5-oxo-2,5-dihydrofuran-2-yl)-2-hydroxyethyl tetradecanoate using HPLC-ESI/MS and 2D [H-H] NMR COSY. The hydrophilic-lipophilic balance of EM was 11.5, suggesting that EM could be proper to stabilize oil-in-water emulsions. Moreover, isothermal titration calorimetry demonstrated the micellar thermodynamic behavior of EM and determined its critical micelle concentration (0.36 mM). In terms of antioxidative property, EM exhibited the radical scavenging activity against DPPH (EC: 35.47 ± 0.13 μM) and ABTS (EC: 36.45 ± 1.98 μM) radicals. Finally, EM showed bacteriostatic and bactericidal activities against Gram-positive foodborne pathogens (minimum inhibitory concentration: 0.06-0.60 mM; minimum bactericidal concentration: 0.07-0.93 mM).
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http://dx.doi.org/10.1016/j.foodchem.2021.129459DOI Listing
August 2021

Advances in gelatin-based hydrogels for wound management.

J Mater Chem B 2021 02 20;9(6):1503-1520. Epub 2021 Jan 20.

Department of Bioengineering and Nano-bioengineering, Incheon National University, Korea. and Division of Bioengineering, College of Life Sciences and Bioengineering, Incheon National University, Korea.

Skin wounds can be classified into two categories, namely acute and chronic wounds. While acute wounds are healed by the normal wound healing process, chronic wounds are not normally healed, causing inflammation, pain, discomfort, serious complications, and economic burden owing to treatment costs. To alleviate and treat chronic wounds, various biomaterials have been developed. Among them, in situ forming polymeric hydrogels have been widely used as a promising wound care material due to their beneficial properties, including sol-gel phase transition, moisturizing effect on the surrounding environment, biocompatibility, and structural similarity to the native extracellular matrix. The development of bioactive hydrogels that provide artificial cellular microenvironments or stimulate surrounding tissues through physicochemical and biological stimuli is an emerging trend in the fabrication of hydrogels. Notably, gelatin-based hydrogels have attracted much attention as bioactive matrices owing to their biocompatibility, biodegradability, and various functional moieties for chemical modification. In this review, we discuss the development and use of advanced gelatin-based hydrogels for wound management and tissue regeneration.
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http://dx.doi.org/10.1039/d0tb02582hDOI Listing
February 2021

Calcium peroxide-mediated formation of multifunctional hydrogels with enhanced mesenchymal stem cell behaviors and antibacterial properties.

J Mater Chem B 2020 12;8(48):11033-11043

Department of Molecular Science and Technology, Ajou University, 5 Woncheon, Yeongtong, Suwon 16499, Republic of Korea.

Injectable hydrogels can serve as therapeutic vehicles and implants for the treatment of various diseases as well as for tissue repair/regeneration. In particular, the horseradish peroxidase (HRP) and hydrogen peroxide (H2O2)-catalyzed hydrogelation system has attracted much attention, due to its ease of handling and controllable gel properties. In this study, we introduce calcium peroxide (CaO2) as a H2O2-generating reagent to gradually supply a radical source for the HRP-catalyzed crosslinking reaction. This novel therapy can create stiff hydrogels without compromising the cytocompatibility of the hydrogels due to the use of initially high concentrations of H2O2. The physico-chemical properties of the hydrogels can be controlled by varying the concentrations of HRP and CaO2. In addition, the controlled and sustained release of bioactive molecules, including H2O2, O2, and Ca2+ ions, from the hydrogels could stimulate the cellular behaviors (attachment, migration, and differentiation) of human mesenchymal stem cells. Moreover, the hydrogels exhibited killing efficacy against both Gram-negative and Gram-positive bacteria, dependent on the H2O2 and Ca2+ release amounts. These positive results suggest that hydrogels formed by HRP/CaO2 can be used as potential matrices for a wide range of biomedical applications, such as bone regeneration and infection treatment.
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http://dx.doi.org/10.1039/d0tb02119aDOI Listing
December 2020

Regulation of intracellular transition metal ion level with a pH-sensitive inorganic nanocluster to improve therapeutic angiogenesis by enriching conditioned medium retrieved from human adipose derived stem cells.

Nano Converg 2020 Oct 16;7(1):34. Epub 2020 Oct 16.

School of Chemical Engineering, Sungkyunkwan University, Suwon, 440-746, Republic of Korea.

Cell therapy based on human adipose derived stem cells (hADSCs) is a known potential therapeutic approach to induce angiogenesis in ischemic diseases. However, the therapeutic efficacy of direct hADSC injection is limited by a low cell viability and poor cell engraftment after administration. To improve the outcomes of this kind of approach, various types of nanoparticles have been utilized to improve the therapeutic efficacy of hADSC transplantation. Despite their advantages, the adverse effects of nanoparticles, such as genetic damage and potential oncogenesis based on non-degradable property of nanoparticles prohibit the application of nanoparticles toward the clinical applications. Herein, we designed a transition metal based inorganic nanocluster able of pH-selective degradation (ps-TNC), with the aim of enhancing an hADSC based treatment of mouse hindlimb ischemia. Our ps-TNC was designed to undergo degradation at low pH conditions, thus releasing metal ions only after endocytosis, in the endosome. To eliminate the limitations of both conventional hADSC injection and non-degradable property of nanoparticles, we have collected conditioned medium (CM) from the ps-TNC treated hADSCs and administrated it to the ischemic lesions. We found that intracellular increment of transition metal ion upregulated the hypoxia-inducible factor 1α, which can induce vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) expressions. Based on the molecular mechanism, the secretion of VEGF and bFGF by ps-TNC treated hADSCs showed a significant improvement compared to that of untreated cells. Injecting the CM collected from ps-TNC treated hADSCs into the mouse hindlimb ischemia model (ps-TNC-CM group) showed significantly improved angiogenesis in the lesions, with improved limb salvage and decreased muscle degeneration compared to the group injected with CM collected from normal hADSCs (CM group). This study suggests a novel strategy, combining a known angiogenesis molecular mechanism with both an improvement on conventional stem cell therapy and the circumvention of some limitations still present in modern approaches based on nanoparticles.
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http://dx.doi.org/10.1186/s40580-020-00244-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7567771PMC
October 2020

Cognitive behavioral therapy for insomnia in restless legs syndrome patients.

Sleep Med 2020 10 19;74:227-234. Epub 2020 Jul 19.

Department of Neurology, Keimyung University, School of Medicine, Daegu, South Korea. Electronic address:

Objectives: The purpose of this study was to investigate the effects of cognitive behavioral therapy for insomnia (CBTI) in patients with Restless Legs Syndrome (RLS).

Methods: This is a randomized controlled study. The patients were sequentially selected and randomly assigned to either a CBTI group or a non-CBTI group. A total of 25 RLS patients with comorbid insomnia were recruited from a tertiary university hospital sleep center. Twelve were assigned to the CBTI group, and 13 were assigned to the non-CBTI group. The CBTI group received 4 sessions of behavioral therapy, while the non-CBTI group received one informative session on sleep hygiene. All patients completed sleep and psychiatric-related questionnaires. In addition, each individual completed a one-week sleep log for collecting subjective sleep data and actigraphy for objective sleep data.

Results: After conducting the CBTI, there were significant improvements in severity of insomnia symptoms, subjective sleep efficiency, total sleep time, latency to sleep onset, wake after sleep onset, objective latency to sleep onset, and anxiety in the CBTI group as compared to the non-CBTI group. The effect of CBTI on sleep-related data was maintained for up to three months.

Conclusions: CBTI was effective in RLS patients by improving sleep quality and anxiety symptoms. CBTI may be considered in clinical practice for RLS patients with comorbid insomnia.
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http://dx.doi.org/10.1016/j.sleep.2020.07.011DOI Listing
October 2020

Catalytic characterization of heterodimeric linoleate 13S-lipoxygenase from black soybean (Glycine max (L.) Merr.).

Enzyme Microb Technol 2020 Sep 20;139:109595. Epub 2020 May 20.

Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul 08826, Republic of Korea; Center for Agricultural Microorganism and Enzyme, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea. Electronic address:

A novel lipoxygenase (BLOX) was purified from black soybean (Glycine max (L.) Merr.), and its catalytic properties were characterized. The molecular weight of BLOX was 101 kDa and its unique heterodimeric structure with two different subunits of molecular weight 46 kDa and 55 kDa was elucidated. The optimum pH and temperature of BLOX were pH 9.5 and 40 °C, respectively. BLOX was highly stable at the pH range of 6.0-10.0 and below 40 °C, and was stimulated by adding ferrous ion (Fe). In terms of substrate specificity, BLOX showed a substrate preference to linoleic acid that is the main substance to produce hydroperoxides in soybean. When it reacted with linoleic acid, the major product was 13(S)-hydroperoxy-9,11-octadecadienoic acid; therefore, it could be classified into the linoleate 13S-LOX family (EC 1.13.11.12). Finally, the kinetic parameters (V, K, and k) of BLOX were 0.124 mM min, 0.636 mM, and 12.28 s, respectively, and consequently, the catalytic efficiency (k/K) was calculated as 1.93 × 10 M·s. These catalytic characteristics of BLOX could contribute to understanding the enzymatic rancidification of black soybean, and to further biotechnical approaches to control and mitigate the deterioration.
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http://dx.doi.org/10.1016/j.enzmictec.2020.109595DOI Listing
September 2020

Design of Advanced Polymeric Hydrogels for Tissue Regenerative Medicine: Oxygen-Controllable Hydrogel Materials.

Adv Exp Med Biol 2020 ;1250:63-78

Department of Bioengineering and Nano-Bioengineering, Incheon National University, Incheon, Republic of Korea.

Engineered polymeric hydrogels have been extensively utilized in tissue engineering and regenerative medicine because of their biocompatibility, tunable properties, and structural similarity in their native extracellular microenvironment. The native extracellular matrix (ECM) has been implicated as a crucial factor in the regulation of cellular behaviors and their fate. The emerging trend in the design of hydrogels involves the development of advanced materials to precisely recapitulate the native ECM or to stimulate the surrounding tissues via physical, chemical, or biological stimuli. The ECM presents various parameters such as ECM components, soluble factors, cell-to-cell and cell-to-matrix interactions, physical forces, and physicochemical environments. Among these environmental factors, oxygen is considered as an essential signaling molecule. In particular, abnormal oxygen tension such as a lack of oxygen (defined as hypoxia) and an excess supply of oxygen (defined as hyperoxia) plays a pivotal role during early vascular development, tissue regeneration and repair, and tumor progression and metastasis. In this chapter, we discuss how engineered polymeric hydrogels serve as either an artificial extracellular microenvironment to create engineered tissues or as an acellular matrix to stimulate the native tissues for a wide range of biomedical applications including tissue engineering and regenerative medicine, wound healing, and engineered disease models. Specifically, we focus on emerging technologies to create advanced polymeric hydrogel materials that accurately mimic or stimulate the native ECM.
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http://dx.doi.org/10.1007/978-981-15-3262-7_5DOI Listing
August 2020

Effects of a labour and delivery simulated practice programme for elderly primigravidas.

Nurs Open 2020 05 22;7(3):776-782. Epub 2020 Jan 22.

Keimyung University Daegu South Korea.

Aim: Increasing numbers of older gravidas compel research into best practices for their labour-related outcomes. Responding to this need, this study sought to develop and evaluate a programme for older primigravidas.

Design: The authors developed a simulated practice programme for older primigravidas and tested its effects.

Methods: A non-equivalent control group pre- and post-test design was used with 49 community-dwelling primigravidas. The programme taught the stages of labour using a realistic scenario-based practice and a debriefing session. Data were collected between June and September 2015. Participants were divided into intervention ( = 25) and control ( = 24) groups. Postintervention group effects were analysed with independent tests.

Results: The intervention group's levels of anxiety and stress decreased and their knowledge and self-confidence increased. The intervention group's labour duration was also shorter than that of the control group.
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http://dx.doi.org/10.1002/nop2.450DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7113517PMC
May 2020

Lipase-catalyzed synthesis of lauroyl tripeptide-KHA with multi-functionalities: Its surface-active, antibacterial, and antioxidant properties.

Food Chem 2020 Jul 1;319:126533. Epub 2020 Mar 1.

Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea. Electronic address:

Lipase-catalyzed acylation of a hydrophilic tripeptide-KHA (TP-KHA; amino acid sequence Lys-His-Ala) with a lipophilic lauric acid was performed to produce a multi-functional compound, lauroyl tripeptide-KHA (TPL-KHA), with surface, antibacterial, and antioxidant activities. The significant acylation reaction parameters were optimized as follows: organic solvent of 2-methyl-2-butanol, reaction temperature at 55 °C, substrate molar ratio (lauric acid:TP-KHA) of 4.0, and reaction time for 72 h. Structural analyses by LC-ESI-MS and H NMR identified that N-lauroyl tripeptide-KHA was chemo-selectively synthesized by the acylation reaction under the optimum conditions. TPL-KHA showed the surface activity at the air-water interface with critical micelle concentration (CMC) of 2.71 mM and γ of 30.44 mN/m. TPL-KHA exhibited bacteriostatic and bactericidal effects on Gram-positive and Gram-negative foodborne pathogens (minimum inhibitory concentrations: 2.83-4.00 mM, minimum bactericidal concentrations: 3.17-5.83 mM). Moreover, it was demonstrated that TPL-KHA had the ability to scavenge ABTS radicals and inhibit the lipid oxidation.
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http://dx.doi.org/10.1016/j.foodchem.2020.126533DOI Listing
July 2020

Enterotoxin Genes, Antibiotic Susceptibility, and Biofilm Formation of Low-Temperature-Tolerant Isolated from Green Leaf Lettuce in the Cold Chain.

Foods 2020 Feb 25;9(3). Epub 2020 Feb 25.

Food Biotechnology, Korea University of Science & Technology, Daejeon 34113, Korea.

The prevalence and characteristics of low-temperature-tolerant (psychrotolerant ) in green leaf lettuce collected during cold chain were investigated. Among the 101 isolated samples, only 18 were capable of growth at 7 °C, and these isolates shared potential health hazard characteristics with mesophilic isolates. Most psychrotolerant isolates contained various combinations of , and Most isolates of psychrotolerant possessed at least two enterotoxin genes and 28% of isolates harbored tested nine enterotoxin genes. Additionally, the psychrotolerant isolates showed resistance to tetracycline and rifampin and intermediate levels of resistance to clindamycin. A total of 23% of isolates among psychrotolerant displayed a high level of biofilm formation at 7 °C than at 10 °C or 30 °C. The results of this study indicate that cold distribution and storage for green leaf lettuce may fail to maintain food safety due to the presence of enterotoxigenic, antibiotic-resistant, and strong biofilm forming psychrotolerant isolates, which therefore poses a potential health risk to the consumer. Our findings provide the first account of the prevalence and characteristics of psychrotolerant isolated from green leaf lettuce during cold storage, suggesting a potential hazard of psychrotolerant isolates to public health and the food industry.
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http://dx.doi.org/10.3390/foods9030249DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7142467PMC
February 2020

The Bactericidal Effect of a Combination of Food-Grade Compounds and their Application as Alternative Antibacterial Agents for Food Contact Surfaces.

Foods 2020 Jan 7;9(1). Epub 2020 Jan 7.

Department of Food Biotechnology, University of Science & Technology, Daejoen 34113, Korea.

Chemical antibacterials are widely used to control microbial growth but have raised concerns about health risks. It is necessary to find alternative, non-toxic antibacterial agents for the inhibition of pathogens in foods or food contact surfaces. To develop a non-toxic and "green" food-grade alternative to chemical sanitizers, we formulated a multicomponent antibacterial mixture containing L., L., citric acid, and ε-polylysine and evaluated its bactericidal efficacy against , , , Enteritidis, and on food contact surfaces. A combination of the agents allowed their use at levels lower than were effective when tested individually. At a concentration of 0.25%, the multicomponent mixture reduced viable cell count by more than 5 log CFU/area, with complete inactivation 24 h after treatment. The inhibitory efficacy of the chemical antibacterial agent (sodium hypochlorite, 200 ppm) and the multicomponent antibacterial mixture (0.25%) on utensil surfaces against , , Enteritidis, and were similar, but the multicomponent system was more effective against than sodium hypochlorite, with an immediate 99.999% reduction on knife and plastic basket surfaces, respectively, and within 2 h on cutting board surfaces after treatment. A combination of these food-grade antibacterials could be a useful strategy for inhibition of bacteria on food contact surfaces while allowing use of lower concentrations of its components than are effective individually. This multicomponent food-grade antibacterial mixture may be a suitable "green" alternative to chemical sanitizers.
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http://dx.doi.org/10.3390/foods9010059DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7022224PMC
January 2020

Morphology, morphogenesis, and molecular phylogeny of a new freshwater ciliate, Gonostomum jangbogoensis n. sp. (Ciliophora, Hypotricha), from Victoria Land, Antarctica.

Eur J Protistol 2020 Apr 3;73:125669. Epub 2020 Jan 3.

Division of Polar Life Sciences, Korea Polar Research Institute, Incheon 21990, South Korea. Electronic address:

In a study on ciliate diversity, we discovered the new hypotrich species, Gonostomum jangbogoensis n. sp., in freshwater from Terra Nova Bay, Victoria Land, southeast Antarctica. We describe its morphology and morphogenesis using standard methods, and the SSU rRNA gene phylogeny is provided as well. Morphology of Gonostomum jangbogoensis n. sp. is characterized as follows: slender to elongated body shape; grayish under low magnification; cortical granules present; 32-41 adoral membranelles; 3 enlarged frontal cirri; 1 buccal cirrus; 2 frontoterminal cirri; 3 or 4 frontoventral cirral pairs, 2 pretransverse cirri, 6-7 transverse cirri; 13-19 left and 18-26 right marginal cirri; 17-23 paroral kinetids; 3 dorsal kineties; 3 caudal cirri; 2 macronuclear nodules with 1-3 micronuclei. The morphogenesis of the new species confirms that it has at least seven frontal-ventral-transverse cirral anlagen, which is also reported in Gonostomum sp. 1 sensu Shin from Korea. Even though these two populations occur very far from each other, the morphometric data prove that this character state, the seven cirral anlagen, is a stable feature across these populations and might be an apomorphy. The phylogenetic analyses show that the genus Gonostomum is non-monophyletic and that the new species is a sister to G. bromelicola.
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http://dx.doi.org/10.1016/j.ejop.2019.125669DOI Listing
April 2020

In situ forming and reactive oxygen species-scavenging gelatin hydrogels for enhancing wound healing efficacy.

Acta Biomater 2020 02 14;103:142-152. Epub 2019 Dec 14.

Department of Molecular Science and Technology, Ajou University, 5 Woncheon, Yeongtong, Suwon, 443-749, Republic of Korea. Electronic address:

The overexpression of reactive oxygen species (ROS) contributes to the pathogenesis of numerous diseases such as atherosclerosis, myocardial infarction, cancer, and chronic inflammation. Therefore, the development of materials that can locally control the adverse effects resulting from excessive ROS generation is of great significance. In this study, the antioxidant gallic acid-conjugated gelatin (GGA) was introduced into gelatin-hydroxyphenyl propionic (GH) hydrogels to create an injectable hydrogel with enhanced free radical scavenging properties compared to pure GH hydrogels. The modified hydrogels were rapidly formed by an HRP-catalyzed cross-linking reaction with high mechanical strength and biodegradability. The resulting GH/GGA hydrogels effectively scavenged the hydroxyl radicals and DPPH radicals, and the scavenging capacity could be modulated by varying GGA concentrations. Moreover, in an in vitro HO-induced ROS microenvironment, GH/GGA hydrogels significantly suppressed the oxidative damage of human dermal fibroblast (hDFBs) and preserved their viability by reducing intracellular ROS production. More importantly, the ROS scavenging hydrogel efficiently accelerated the wound healing process with unexpected regenerative healing characteristics, shown by hair follicle formation; promoted neovascularization; and highly ordered the alignment of collagen fiber in a full-thickness skin defect model. Therefore, we expect that injectable GH/GGA hydrogels can serve as promising biomaterials for tissue regeneration applications, including wound treatment and other tissue repair related to ROS overexpression. STATEMENT OF SIGNIFICANCE: Recently, many researchers have endeavored to develop injectable hydrogel matrices that can modulate the ROS level to normal physiological processes for the treatment of various diseases. Here, we designed an injectable gelatin hydrogel in which gallic acid, an antioxidant compound, was conjugated onto a gelatin polymer backbone. The hydrogels showed tunable properties and could scavenge the free radicals in a controllable manner. Because of the ROS scavenging properties, the hydrogels protected the cells from the oxidative damage of ROS microenvironment and effectively accelerated the wound healing process with high quality of healed skin. We believe that this injectable ROS scavenging hydrogel has great potential for wound treatment and tissue regeneration, where oxidative damage by ROS contributes to the pathogenesis.
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http://dx.doi.org/10.1016/j.actbio.2019.12.009DOI Listing
February 2020

Inhibitory characteristics of flavonol-3-O-glycosides from Polygonum aviculare L. (common knotgrass) against porcine pancreatic lipase.

Sci Rep 2019 12 2;9(1):18080. Epub 2019 Dec 2.

Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, Republic of Korea.

Pancreatic lipase (PL) is an enzyme that plays an essential role in the digestion of dietary lipids and is a suitable target for an anti-obesity dietary supplement. The objective of this study was to find a novel source of PL inhibitors from Korean medicinal plants and investigate the PL-inhibitory properties of the active constituents. From among 34 kinds of methanolic crude extracts, Polygonum aviculare L. showed the highest PL-inhibitory activity (63.97 ± 0.05% of inhibition). Solvent fractionation and liquid chromatography/mass spectrometry (LC/MS) analysis identified flavonol-3-O-glycosides, flavonol-3-O-(2″-galloyl)-glycosides, and flavonol aglycones as active constituents. Furthermore, the inhibitory characteristics of the major compounds were investigated in terms of enzyme kinetics and fluorescence quenching. The results suggested that the inhibitory activity of the major compounds is closely related to the tertiary structural change in PL, and that differences in inhibitory activity occurred due to slight discrepancies in their chemical structure.
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http://dx.doi.org/10.1038/s41598-019-54546-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6889161PMC
December 2019

[Effects of a Reinforcement Program for Postpartum Care Behavioral Skills of Couples with Their First Baby].

J Korean Acad Nurs 2019 Apr;49(2):137-148

College of Nursing, Keimyung University, Daegu, Korea.

Purpose: This study aimed to investigate the effects of a reinforcement program for behavioral skills in postpartum care for couples with their first baby.

Methods: The study used a non-equivalent control group and pretest-posttest design. It was conducted from January 14 to April 10, 2016 at a postpartum care center in D city. It analyzed 43 couples (22 in the experimental group and 21 in the control group.) For data analysis, descriptive statistics, test of homogeneity in pretest, independent t-tests, and repeated measures ANOVA were used.

Results: For maternal fulfillment of postpartum care and postpartum fatigue, there was no significant difference in the interaction between group and time. In terms of parent-newborns attachment, the interaction between group and time showed a significant difference for mothers (F=13.63, =.001) and fathers (F=6.51, =.001). In marital intimacy, the interaction between group and time showed a significant difference for mothers (F=14.40, <.001) and fathers (F=9.46, =.004). In parenting stress, the interaction between group and time showed a significant difference for mothers (F=31.8, <.001) and fathers (F=11.69, =.001). A significant difference was found for the mothers' postpartum sleeping hours (F=0.14 =.004).

Conclusion: This program for behavioral skills in postpartum care, which is based on the information-motivation-behavioral skills model, improves postpartum care, parent-newborn attachment, marital intimacy, parenting stress, and maternal postpartum sleeping, by reinforcing behavioral skills required for postpartum care.
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http://dx.doi.org/10.4040/jkan.2019.49.2.137DOI Listing
April 2019

Effect of intense pulsed light on the deactivation of lipase: Enzyme-deactivation kinetics and tertiary structural changes by fragmentation.

Enzyme Microb Technol 2019 May 5;124:63-69. Epub 2019 Feb 5.

Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul, 08826, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea. Electronic address:

The effect of intense pulsed light (IPL) irradiation on Chromobacterium viscosum lipase was investigated with a primary focus on catalytic activity and molecular structure. During IPL irradiation, lipase activity decreased significantly with increasing pulse fluence (F) and exposure time (t). IPL-induced deactivation kinetics were further elucidated based on a two-step series-type deactivation model (constant deactivation rate k >k). F was found to be the dominant variable affecting the degree of lipase deactivation, and residual activity was not associated with increasing t below a certain F energy density (2.66 mJ/cm), implying a critical threshold for IPL-induced deactivation of lipase. From the results of fluorescence spectroscopy and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), we determined that IPL-induced deactivation was caused by fragmentation, leading to lipase tertiary structural changes. Furthermore, the results of FindPept analysis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) indicated that the internal sensitive bonds of lipase were cleaved preferentially by IPL, such that IPL irradiation induced site-sensitive fragmentation and peptide bond cleavage.
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http://dx.doi.org/10.1016/j.enzmictec.2019.02.001DOI Listing
May 2019

In Situ Cross-Linkable Hydrogels as a Dynamic Matrix for Tissue Regenerative Medicine.

Tissue Eng Regen Med 2018 Oct 27;15(5):547-557. Epub 2018 Aug 27.

2Department of Molecular Science and Technology, Ajou University, 5 Woncheon, Yeongtong, Suwon, 16499 Republic of Korea.

Background: Polymeric hydrogels are extensively used as promising biomaterials in a broad range of biomedical applications, including tissue engineering, regenerative medicine, and drug delivery. These materials have advantages such as structural similarity to the native extracellular matrix (ECM), multi-tunable physicochemical and biological properties, and biocompatibility.

Methods: In situ forming hydrogels show a phase transition from a solution to a gel state through various physical and chemical cross-linking reactions. These advanced hydrogel materials have been widely used for tissue regenerative medicine because of the ease of encapsulating therapeutic agents, such as cells, drugs, proteins, and genes.

Results: With advances in biomaterials engineering, these hydrogel materials have been utilized as either artificial cellular microenvironments to create engineered tissue constructs or as bioactive acellular matrices to stimulate the native ECM for enhanced tissue regeneration and restoration.

Conclusion: In this review, we discuss the use of in situ cross-linkable hydrogels in tissue engineering and regenerative medicine applications. In particular, we focus on emerging technologies as a powerful therapeutic tool for tissue regenerative medicine applications.
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http://dx.doi.org/10.1007/s13770-018-0155-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6171695PMC
October 2018

Catalytic characteristics of a sn-1(3) regioselective lipase from Cordyceps militaris.

Biotechnol Prog 2019 03 5;35(2):e2744. Epub 2018 Dec 5.

Dept. of Agricultural Biotechnology, Seoul National University, Seoul, 08826, Republic of Korea.

A total of 39 agricultural products were screened for natural sources of lipases with distinctive positional specificity. Based on this, Cordyceps militaris lipase (CML) was selected and subsequently purified by sequential chromatography involving anion-exchange, hydrophobic-interaction, and gel-permeation columns. As a result of the overall purification procedure, a remarkable increase in the specific activity of the CML (4.733 U/mg protein) was achieved, with a yield of 2.47% (purification fold of 94.54). The purified CML has a monomeric structure with a molecular mass of approximately 62 kDa. It was further identified as a putative extracellular lipase from C. militaris by the partial sequence analysis using ESI-Q-TOF MS. In a kinetic study of the CML-catalyzed hydrolysis, the values of V , K , and k were determined to be 4.86 μmol·min ·mg , 0.07 mM, and 0.29 min , respectively. In particular, the relatively low K value indicated that CML has a high affinity for its substrate. With regard to positional specificity, CML selectively cleaved triolein at the sn-1 or 3 positions of glycerol backbone, releasing 1,2(2,3)-diolein as the major products. Therefore, CML can be considered a distinctive biocatalyst with sn-1(3) regioselectivity. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2744, 2019.
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http://dx.doi.org/10.1002/btpr.2744DOI Listing
March 2019

Morphology and phylogeny of a new species, Uroleptus (Caudiholosticha) antarctica n. sp. (Ciliophora, Hypotricha) from Greenwich Island in Antarctica.

Zootaxa 2018 Sep 24;4483(3):591-599. Epub 2018 Sep 24.

Division of Polar Life Sciences, Korea Polar Research Institute, Incheon 21990, South Korea Department of Biological Sciences, Inha University, Incheon 22212, South Korea Department of Biological Resources Research, National Institute of Biological Resources, Incheon 22689, South Korea.

This paper describes the morphological features based on standard methods and estimates their phylogenetic position using small subunit ribosomal RNA (SSU rRNA) sequences of a Uroleptus (Caudiholosticha) antarctica n. sp. population investigated from moss of the Greenwich Island, Antarctica. The morphology of Uroleptus (Caudiholosticha) antarctica n. sp. is characterized as follows: 213.0-238.0×67.5-74.5 μm size in vivo; contractile vacuole located slightly above left of mid-body; cortical granules lacking; three frontal and two frontoterminal cirri; five to six transverse cirri; one pretransverse cirri; one right and one left marginal rows; six to seven dorsal kineties; three caudal cirri.
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http://dx.doi.org/10.11646/zootaxa.4483.3.10DOI Listing
September 2018

Hydrophilic and lipophilic characteristics of non-fatty acid moieties: significant factors affecting antibacterial activity of lauric acid esters.

Food Sci Biotechnol 2018 Apr 15;27(2):401-409. Epub 2018 Mar 15.

2Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826 Republic of Korea.

It has been proposed that the hydrophilic and/or lipophilic characteristics of fatty acid derivatives affect their antibacterial activities according to their ability to incorporate into the bacterial cell membrane. To verify this hypothesis, six kinds of lauric acid derivatives esterified with different non-fatty acid moieties were selected to confirm whether antibacterial activity from their precursor (i.e., lauric acid) is retained or lost. Three compounds, monolaurin, sucrose laurate, and erythorbyl laurate, exerted bacteriostatic and bactericidal effects against Gram-positive bacteria, while the others showed no inhibitory activity. Interestingly, the calculated log (octanol-water partition coefficient) values of monolaurin, sucrose laurate, and erythorbyl laurate were - 4.122, - 0.686, and 3.670, respectively, relatively lower than those of the other compounds without antibacterial activity. Moreover, the hydrophilic-lipophilic balance values of the three compounds with antibacterial activity were higher than those of the other compounds, corresponding to the log result.
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http://dx.doi.org/10.1007/s10068-018-0353-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6049658PMC
April 2018

Cloning and protein expression of the sn-1(3) regioselective lipase from Cordyceps militaris.

Enzyme Microb Technol 2018 Dec 25;119:30-36. Epub 2018 Aug 25.

Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea. Electronic address:

In this study, the gene of a novel lipase with sn-1(3) regioselectivity (i.e., sn-1 or sn-3 specific) from Cordyceps militaris was successfully expressed by a heterologous expression system. Total RNA was extracted from C. militaris and then single-stranded cDNA was synthesized. The resulting C. militaris lipase (CML) gene was inserted in Escherichia coli expression plasmids [pET-29b(+), pET-26b, and pColdIII] to construct plasmids encoding CML, which were then transformed to E. coli strains BL21 (DE3), C43 (DE), C41 (DE3), and Origami (DE3) for protein expression. Although the recombinant CML expression level was high, it was overproduced in the form of inclusion bodies. Under a specific condition, the soluble form of the recombinant CML was detected using Western blot analysis; however, no enzyme activity was observed. To overcome the lack of post-translational modifications in recombinant CML, a baculovirus-insect expression system was introduced for eukaryotic lipase expression. pDualBac was used as the transfer vector, and the CML gene was fused under the control of the polyhedrin promoter. After generating the recombinant baculovirus, the active form of CML was successfully produced and its kinetic parameters were determined.
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http://dx.doi.org/10.1016/j.enzmictec.2018.08.008DOI Listing
December 2018

Lipase-catalyzed solvent-free synthesis of erythorbyl laurate in a gas-solid-liquid multiphase system.

Food Chem 2019 Jan 20;271:445-449. Epub 2018 Jul 20.

Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea. Electronic address:

Erythorbyl laurate is a potential food additive as a multi-functional emulsifier having antioxidant and antimicrobial activities. In this study, a gas-solid-liquid multiphase system (GSL-MPS) was established to enhance the production yield of erythorbyl laurate in a lipase-catalyzed solvent-free synthesis. The significant reaction variables were optimized as follows: substrate molar ratio of 2:1 (lauric acid:erythorbic acid) and enzyme concentration of 120 mg/mL (840 PLU/mL). Under these conditions, the maximum production yield in GSL-MPS was 13.974 mg/mL, which is 8.60- and 4.26-fold higher than the yields obtained in an organic solvent monophase system (OS-MPS) and a solid-liquid biphase system (SL-BPS), respectively. Moreover, the operational stability of the immobilized lipase was significantly improved in GSL-MPS compared with OS-MPS. These results indicate that GSL-MPS can be an enzymatic reaction system facilitating efficient production of ester compounds as a means of increasing production yields and the reusability of the immobilized lipase.
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http://dx.doi.org/10.1016/j.foodchem.2018.07.134DOI Listing
January 2019

Catechol-rich gelatin hydrogels in situ hybridizations with silver nanoparticle for enhanced antibacterial activity.

Mater Sci Eng C Mater Biol Appl 2018 Nov 19;92:52-60. Epub 2018 Jun 19.

Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Republic of Korea. Electronic address:

Recently, the interest in antimicrobial hydrogels with impregnated antibacterial agents has significantly increased because of their ability to combat infection in biomedical applications, including wound management, tissue engineering, and biomaterial surface coating. Among these antibacterial reagents, silver nanoparticles (AgNP) show good antibacterial activity against both gram-negative and gram-positive bacteria, including highly multi-resistant strains. However, the entrapment of AgNP within a hydrogel matrix is often associated with toxicity issues because of the use of chemical reductants (e.g., commonly sodium borohydride), burst leaching, or unwanted agglomeration of AgNP in the absence of surfactants or stabilizers. In this study, we present catechol-rich gelatin hydrogels with in situ hybridization of AgNP for enhanced antimicrobial activities. AgNP were formed through a redox reaction between silver ions and the catechol moieties of a gelatin derivative polymer, without the addition of any chemical reductants. The AgNP with an average size of 20 nm were entrapped within hydrogel matrices and showed sustained release from the hydrogel matrix (8.7% for 14 days). The resulting hydrogels could kill both gram-negative and gram-positive bacteria, depending on the amount of AgNP released from the hydrogels and did not have a significant influence on mammalian cell viability. We believe that our catechol-rich hydrogels in situ hybridizations with AgNP have great potential for biomedical applications, such as wound management and surface coating, because of their excellent antibacterial activities and biocompatibility.
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http://dx.doi.org/10.1016/j.msec.2018.06.037DOI Listing
November 2018

Prevalence, Enterotoxin Genes, and Antibiotic Resistance of Bacillus cereus Isolated from Raw Vegetables in Korea.

J Food Prot 2018 10;81(10):1590-1597

1 Department of Food Biotechnology, University of Science & Technology, Daejeon 34113, Republic of Korea; and.

Bacillus cereus has long been recognized as an important pathogen in foodborne poisoning worldwide. Fresh vegetables are often contaminated with enterotoxigenic B. cereus and have been implicated as a vehicle for the transmission of this bacterium. This study reports on the occurrence, virulence gene profile, and antibiotic resistance of B. cereus in fresh vegetables. Of 102 examined samples, 48 (47%) of the samples were contaminated with B. cereus (>1 log CFU/g) and 7 (6.8%) of the samples showed more than 3 log CFU/g. In total, 118 B. cereus isolates were examined for the virulence genes nheA, nheB, nheC, hblA, hblC, hblD, cytK, and entFM and for resistance to antibiotics. Of these B. cereus isolates, 70% harbored nheA, nheB, nheC, and cytK. Eighteen (80%) of 21 isolates from bell peppers possessed eight enterotoxin genes. B. cereus isolates were susceptible to imipenem, vancomycin, gentamicin, erythromycin, ciprofloxacin, and chloramphenicol, whereas 22.4% of isolates from garlic chives, 48.7% from perilla leaf, and 40.5% from romaine lettuce showed antibiotic resistance to rifampin and 6% of isolates from garlic chives exhibited resistance to tetracycline. Three isolates from garlic chives were resistant to both tetracycline and rifampin. Raw vegetables were revealed to be major sources of B. cereus containing multiple toxin genes and exhibiting antibiotic resistance. Therefore, the potential health risks of consuming these vegetables raw or undercooked should not be underestimated. This study provides basic information for monitoring the antibiotic resistance and toxigenicity of B. cereus in the food chain during vegetable distribution and for developing food safety management to reduce the contamination with and transmission of B. cereus.
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http://dx.doi.org/10.4315/0362-028X.JFP-18-205DOI Listing
October 2018

Hyperbaric oxygen-generating hydrogels.

Biomaterials 2018 11 15;182:234-244. Epub 2018 Aug 15.

Department of Bioengineering and Nano-Bioengineering, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea. Electronic address:

Oxygen plays a critical role as a substrate for metabolism and as a signaling molecule regulating cellular activities. In particular, hyperbaric oxygen has been demonstrated to facilitate wound healing processes, including cell proliferative activity, tissue growth, and vascular recruitment, via transient oxidative stress in surrounding tissues. In this study, we report hyperbaric oxygen-generating (HOG) hydrogels comprising thiolated gelatin (GtnSH) that can form hydrogel networks in situ via a calcium peroxide-mediated oxidative cross-linking reaction with oxygen generation. We demonstrate that the HOG hydrogels rapidly generate molecular oxygen up to hyperoxic levels and maintain hyperoxic levels for up to 12 days in vitro and 4 h in vivo. The HOG hydrogel enhances cell proliferative activities of human dermal fibroblasts and endothelial cells, which are closely related to wound healing and angiogenesis. Moreover, the HOG hydrogel promotes wound healing with enhanced tissue infiltration and vascular recruitment in vivo. The HOG hydrogels is a new type of oxygen-generating biomaterials that have great potential as advanced hydrogel materials for tissue regenerative medicine applications, including the treatment of wound and vascular disorders.
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http://dx.doi.org/10.1016/j.biomaterials.2018.08.032DOI Listing
November 2018
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