Anti-HIV-1 activity of phlorotannin derivative 8,4?-dieckol from Korean brown alga Ecklonia cava.

Karadeniz, Fatih,Kang, Kyong-Hwa,Park, Jae W,Park, Sun-Joo,Kim, Se-Kwon Japan Society for Bioscience, Biotechnology, and A 2014 Bioscience, Biotechnology, and Biochemistry Vol.78 No.7

<P>8,4?-dieckol is a natural product which has been isolated from brown alga, Ecklonia cava. This polyphenolic compound is a phlorotannin derivative with a broad range of bioactivities. Its inhibitory activity on human immunodeficiency virus type-1 (HIV-1) was tested and the results indicated that 8,4?-dieckol inhibited HIV-1 induced syncytia formation, lytic effects, and viral p24 antigen production at noncytotoxic concentrations. Furthermore, it was found that 8,4?-dieckol selectively inhibited the activity of HIV-1 reverse trancriptase (RT) enzyme with 91% inhibition ratio at the concentration of 50?μM. HIV-1 entry was also inhibited by 8,4?-dieckol. According to data from this study, 8,4?-dieckol is an effective compound against HIV-1 with high potential for further studies. These results suggest that it might be used as a drug candidate for the development of new generation therapeutic agents, although further studies on the mechanism of inhibition should be addressed.</P>

Inhibition of MMP-2 and MMP-9 activities by solvent-partitioned Sargassum horneri extracts

Karadeniz, Fatih,Lee, Seul-Gi,Oh, Jung Hwan,Kim, Jung-Ae,Kong, Chang-Suk The Korean Society of Fisheries and Aquatic Scienc 2018 Fisheries and Aquatic Sciences Vol.21 No.6

Background: Matrix metalloproteinases (MMPs) are linked with several complications such as metastasis of cancer progression, oxidative stress, and hepatic fibrosis. Brown seaweeds are being extensively studied for their bioactive molecule content against cancer progression. In this context, Sargassum horneri was reported to possess various bioactivities including antiviral, antimicrobial, and anti-inflammatory partly due to its phenolic compound content. Methods: In this study, potential of S. horneri was evaluated through anti-MMP effect in HT1080 fibrosarcoma cells. S. horneri crude extract was fractionated with organic solvents, namely, water ($H_2O$), n-buthanol (n-BuOH), 85% aqueous methanol (85% aq. MeOH), and n-hexane. The non-toxicity of fraction samples (Sargassum horneri solvent-partitioned extracts (SHEs)) was confirmed by cell-viability assay. SHEs were tested for their ability to inhibit MMP enzymatic activity through gelatin digestion evaluation and cell migration assay. Expressions of MMP-2 and MMP-9 and tissue inhibitors of MMP (TIMPs) were evaluated by reverse transcription and Western blotting. Results: All fractions inhibited the enzymatic activities of MMP-2 and MMP-9 according to gelatin zymography. Except $H_2O$ fraction, fractions hindered the cell migration significantly. All tested fractions suppressed both mRNA and protein levels of MMP-2, MMP-9, TIMP-1, and TIMP-2. Conclusion: Overall, current results suggested that S. horneri has potential to be a good source for anti-MMP agents, and further investigations are underway for better understanding of the action mechanism and isolation and elucidation of the bioactive molecules.

INVESTIGATING EFFECTS OF TURBINE-LIKE BLADES ON GDI SPRAY FORMATION, INJECTOR DEPOSITS AND PARTICULATE EMISSIONS

Karadeniz Hüseyin 한국자동차공학회 2021 International journal of automotive technology Vol.22 No.2

This study investigates effects of a novel GDI injector outer tip design on the airflow behavior, spray formation, injector deposits and engine particulate emissions. The novel design has turbine-like blades that are located on the tip of the injector. The effects of turbine-like blades on the airflow behavior below the injector tip is initially investigated by means of numerical simulations with three simulation parameters: airflow velocity, air wall shear stress and prehole wetting. Simulations show that turbine-like blades increase the airflow velocity within the boundary layer. Consequently, wall shear stress increase over the injector tip. Therefore, the average prehole wetting decreases. Spray measurements show that the air entrainment increases and spray penetration reduces due to blades, which also confirm the increased airflow velocity. According to engine experiments, particulate emissions reduce slightly at high engine loads. Turbine-like blades do not cause a decrease on particulate emissions from low-to-mid engine loads. The deposit formation reduces around preholes and at the outer side of the injector tip. However, deposits cannot be avoided over the dome of the injector tip.

Anti-adipogenic and Pro-osteoblastogenic Activities of Spergularia marina Extract

Karadeniz, Fatih,Kim, Jung-Ae,Ahn, Byul-Nim,Kim, Mihyang,Kong, Chang-Suk The Korean Society of Food Science and Nutrition 2014 Preventive Nutrition and Food Science Vol.19 No.3

This is an Open Access article distributed under the terms of the Creative Commons Attribution For decades, Spergularia marina, a local food that is popular in South Korea, has been regarded as a nutritious source of amino acids, vitamins, and minerals. While several halophytes are reported to possess distinct bioactivities, S. marina has yet to be promoted as a natural source of bioactives. In this study, the effects of S. marina on the adipogenic differentiation of 3T3-L1 fibroblasts and the osteoblastic differentiation of MC3T3-E1 pre-osteoblasts and C2C12 myoblast cells were evaluated. The anti-adipogenic effect of S. marina was assessed by measuring lipid accumulation and adipogenic differentiation marker expression. S. marina treatment significantly reduced lipid accumulation and notably decreased the gene levels of peroxisome proliferator-activated receptor ${\gamma}$, CCAAT/enhancer-binding protein ${\alpha}$, and sterol regulatory element binding protein 1c. In addition, S. marina enhanced osteoblast differentiation, as indicated by increased alkaline phosphatase activity and increased levels of osteoblastogenesis indicators, namely bone morphogenetic protein-2, osteocalcin, and type I collagen. In conclusion, S. marina could be a source of functional food ingredients that improve osteoporosis and obesity. Further studies, including activity-based fractionation, will elucidate the mechanism of action and active ingredients of S. marina, which would provide researchers with a better understanding of the nutraceutical and therapeutic applications of S. marina.

CYCLIC AND CONSTACYCLIC SELF-DUAL CODES OVER R_k

Karadeniz, Suat,Kelebek, Ismail Gokhan,Yildiz, Bahattin Korean Mathematical Society 2017 대한수학회보 Vol.54 No.4

In this work, we consider constacyclic and cyclic self-dual codes over the rings $R_k$. We start with theoretical existence results for constacyclic and cyclic self-dual codes of any length over $R_k$ and then construct cyclic self-dual codes over $R_1={\mathbb{F}}_2+u{\mathbb{F}}_2$ of even lengths from lifts of binary cyclic self-dual codes. We classify all free cyclic self-dual codes over $R_1$ of even lengths for which non-trivial such codes exist. In particular we demonstrate that our constructions provide a counter example to a claim made by Batoul et al. in [1] and we explain why their claim fails.

Toxicity of Silver Nanoparticles and Application of Natural Products on Fabric and Filters as an Alternative

Fatih Karadeniz(파티 카라데니즈),Han Seong Kim(김한성) 한국생명과학회 2018 생명과학회지 Vol.28 No.7

나노 입자는 화장품, 식품, 기계, 화학 산업 등에 다양한 용도로 활용되고 있으며, 그 응용분야가 광범히 하여 나노 입자 사용에 대한 관심과 연구가 지속적으로 증가하고 있는 추세이다. 특히 금속나노 입자 중 하나인 은나노 입자는 항균 및 항진균 효과가 뛰어나 의류, 실내 공기필터, 증류필터 등 다양한 방면에 활용되고 있다. 하지만 은나노 입자의 지속적인 노출 시, 입자 크기와 노출방식에 따라 인체에 독성을 유발하는 것으로 알려져 있어 친환경적이고 생물학적으로 안전한 천연물 유래 소재를 활용한 은나노 입자의 기술개발이 필요하다. 천연물이 적용된 실내필터와 의류는 생산의 용이성, 제품 내구성 및 항균 활성에서 은나노 적용제품과 비교될 수 있는 것으로 나타고 있다. 본 연구에서는 은나노의 생체 내 미치는 독성 메커니즘에 대해 알아보고 은나노의 대안으로 항균 활성을 지닌 천연물의 항균 활성에 대해 기술하고자 한다. There has been increasing attention and research in various nanoparticle applications. Nanoparticles have been used for a variety of purposes in different departments including but not limited to cosmetics, food, machinery, and chemical. A highly sought-after field to use nanoparticles, especially natural or artificial silver nanoparticles (SNPs), is the utilization of their significant antimicrobial properties in daily items such as fabrics, indoor air filters, and, water filtration units where abundant bacterial and fungal growth are inevitable. These applications of SNPs, however, have enabled continuous human exposure and hence paved the way for potential SNP toxicity depending on exposure method and particle size. This potential toxicity has led to researches on safer antimicrobial solutions to be utilized in textile and filtration. In this context, products of natural origin have gained expanding interest due to their eco-friendly, cost-effective, and biologically safe properties along their promising antibacterial and antifungal activities. Natural product-applied fabrics and filters have been shown to be comparable to those that are SNP-treated in terms of ease production, material durability, and antimicrobial efficiency. This article summarizes and assesses the current state of in vitro and in vitro toxicity of SNPs and discusses the potential of natural products as an alternative.

Natural Origin Polymers: Applications as Wound Care Materials

Fatih Karadeniz(파티 카라데니즈),Hye Kyeong Sung(성혜경),Han Seong Kim(김한성) 한국생명과학회 2019 생명과학회지 Vol.29 No.3

상처 치료는 전세계 인류에 영향을 미치는 보건 산업계의 관심사다. 당뇨병과 같은 대사증후군 유병률 증가로 상처에 의한 합병증의 위험이 높아지고 상처치유의 복잡함 때문에 상처의 치료와 관리가 어렵다. 전통적 상처 드레싱은 제한된 보호기능을 제공하며, 상처 드레싱의 치료 능력을 향상시키기 위해 생체고분자 기반의 드레싱들이 개발되고있다. 생체고분자는 생분해성이 뛰어나고 생체적합성이 좋으며 효과적인 상처 관리에 중요한 항균, 항염증, 지혈, 세포증식, 혈관성 활동 등 다양한 효과가 있다. 키토산, 셀룰로오스, 콜라겐, 히알루론산, 알긴산 등의 여러 생체고분자가 이미 상처치유제로 활용되고 있으며 생체고분자를 다른 고분자, 생체활성 분자 및 약물과 결합하여 생리학적 문제 없이 흉터를 최소화하는 새로운 상처 드레싱이 개발되고 있다. 본 논문에서는, 향후의 연구와 활용을 위한 현재의 생체고분자의 상처처리에 대해 알아보았다. Wound care is a health industry concern affecting millions worldwide. Recent increase in metabolic disorders such as diabetes comes with elevated risk of wound-based complications. Treatment and management of wounds are difficult practices due to complexity of the wound healing process. Conventional wound dressings and treatment applications only provide limited benefits which are mainly aimed to keep wound protected from external factors. To improve wound care, recent developments make biopolymers to be of high interest and importance to researchers and medical practitioners. Biopolymers are polymers or natural origin produced by living organisms. They are credited to be highly biocompatible and biodegradable. Currently, studies reported biopolymers to exhibit various health beneficial properties such as antimicrobial, anti-inflammatory, hemostatic, cell proliferative and angiogenic activities which are crucial for effective wound management. Several biopolymers, namely chitosan, cellulose, collagen, hyaluronic acid and alginic acid have been already investigated and applied as wound dressing agents. Different derivatives of biopolymers have also been developed by cross-linking with other molecules, grafting with other polymers, and loading with bioactive agents or drugs which showed promising results towards wound healing without any undesired outcome such as scarring and physiological abnormalities. In this review, current applications of common biopolymers in wound treatment industry are highlighted to be a guide for further applications and studies.

A comparison of COS and its derivatives in respect to their antidiabetic and antiobesity effects

Fatih Karadeniz,Mustafa Zafer Karagozlu,Chang-Suk Kong,Se-Kwon Kim 한국식품영양과학회 2011 한국식품영양과학회 학술대회발표집 Vol.2011 No.10

Bilateral Renal Choriocarcinoma in a Postmenopausal Woman

Tahir Karadeniz,Medih Topsakal,Orkunt Ozkaptan,Cağlar Cakır 대한비뇨의학회 2011 Investigative and Clinical Urology Vol.52 No.7

Choriocarcinoma is the most malignant tumor of gestational trophoblastic neoplasia. It grows rapidly and metastasizes to the lung, liver, and less frequently, the brain. Metastases to the kidney are rare in the literature, and bilateral involvement is even more scarce. Renal involvement of choriocarcinoma is highly exceptional and may mimic renal cell carcinoma. Here we report a case of bilateral renal choriocarcinoma presenting 5 years after a history of a total anterior hysterectomy because of a hydatidiform mole.

6-Acetyl-2,2-Dimethylchroman-4-One Isolated from Artemisia princeps Suppresses Adipogenic Differentiation of Human Bone Marrow-Derived Mesenchymal Stromal Cells via Activation of AMPK

Fatih Karadeniz,오정환,이정임,김호준,서영완,공창숙 한국식품영양과학회 2020 Journal of medicinal food Vol.23 No.3

Obesity is a world-wide health concern with increasing mortality and morbidity rates. Development of novel therapeutic agents for obesity from phytochemicals may lead to the effective prevention and control of obesity and obesity-related complications. 6-acetyl-2,2-dimethylchroman-4-one (1) was isolated from a dietary plant, Artemisia princeps. The antiobesity effect of compound 1 was determined in human bone marrow-derived mesenchymal stromal cells (hBM-MSCs) induced to differentiate into adipocytes. Treatment with compound 1 resulted in decreased lipid accumulation and expression of key adipogenic markers, proliferator-activated receptor-γ, CCAAT/enhancer-binding protein-α, and sterol regulatory element-binding transcription factor 1. It was also shown that compound 1 downregulated the adipogenesis-induced p38 and JNK MAPK activation, while upregulating adipogenesis inhibitory β-catenin-dependent Wnt10b pathway. Compound 1 was also able to stimulate adenosine monophosphate-activated protein kinase phosphorylation, which was suggested to be the underlying mechanism that resulted in inhibition of adipogenesis in hBM-MSCs. In conclusion, 6-acetyl-2,2-dimethylchroman-4-one was identified as a bioactive constituent of A. princeps that exerts antiobesity properties via suppressing adipocyte formation.