• Title/Summary/Keyword: marine natural products

Search Result 235, Processing Time 0.03 seconds

Steroid Components of Marine-Derived Fungal Strain Penicillium levitum N33.2 and Their Biological Activities

  • Chi K. Hoang;Cuong H. Le; Dat T. Nguyen;Hang T. N. Tran;Chinh V. Luu;Huong M. Le;Ha T. H. Tran
    • Mycobiology
    • /
    • v.51 no.4
    • /
    • pp.246-255
    • /
    • 2023
  • Genus Penicillium comprising the most important and extensively studied fungi has been well-known as a rich source of secondary metabolites. Our study aimed to analyze and investigate biological activities, including in vitro anti-cancer, anti-inflammatory and anti-diabetic properties, of metabolites from a marine-derived fungus belonging to P. levitum. The chemical compounds in the culture broth of P. levitum strain N33.2 were extracted with ethyl acetate. Followingly, chemical analysis of the extract leaded to the isolation of three ergostane-type steroid components, namely cerevisterol (1), ergosterol peroxide (2), and (3β,5α,22E)-ergosta-6,8(14),22-triene-3,5-diol (3). Among these, (3) was the most potent cytotoxic against human cancer cell lines Hep-G2, A549 and MCF-7 with IC50 values of 2.89, 18.51, and 16.47 ㎍/mL, respectively, while the compound (1) showed no significant effect against tested cancer cells. Anti-inflammatory properties of purified compounds were evaluated based on NO-production in LPS-induced murine RAW264.7 macrophages. As a result, tested compounds performed diverse inhibitory effects on NO production by the macrophages, with the most significant inhibition rate of 81.37±1.35% at 25 ㎍/mL by the compound (2). Interestingly, compounds (2) and (3) exhibited inhibitory activities against pancreatic lipase and α-glucosidase enzymes in vitro assays. Our study brought out new data concerning the chemical properties and biological activities of isolated steroids from a P. levitum fungus.

Functionalization of Organotrifluoroborates via Cu-Catalyzed C-N Coupling Reaction

  • Lee, Jung-Hyun;Kim, Heejin;Kim, Taejung;Song, Jung Ho;Kim, Won-Suk;Ham, Jungyeob
    • Bulletin of the Korean Chemical Society
    • /
    • v.34 no.1
    • /
    • pp.42-48
    • /
    • 2013
  • Potassium N-heterobiaryltrifluoroborates were successfully prepared via a selective Cu-catalyzed C-N coupling reaction. The $BF_3K$ moiety was well tolerated under the reaction conditions involving CuI and dimethyl-ethylenediamine (DMEDA) in the presence of DMSO. The Pd-catalyzed Suzuki-Miyaura cross couplings of potassium N-heterobiaryltrifluoroborates with bromoarenes were studied to prepare the N-heterotriaryl compounds. Moreover, homocoupling, iodination, and hydroxylation of potassium N-heterobiaryltrifluoroborates provided the corresponding products in high yields.

A Study on the Effect of Chinese Marine Pollution on Chinese Fisheries Export (중국 해양오염의 증대가 중국 수산물 수출에 미치는 영향에 관한 연구)

  • Lin, Xuemei;Kim, Ki-Soo
    • The Journal of Fisheries Business Administration
    • /
    • v.46 no.1
    • /
    • pp.75-91
    • /
    • 2015
  • With the increasing improvement of living standard, people pay more attention to the quality and security of their food. There is an increase in the consumption of aquatic products and a vast prospect of its trade. Fisheries as a major one of the traditional industries in China have significant price advantages and natural resources. However, marine pollution in China is more and more serious and the expecting of aquatic products has been seriously influenced by green barriers in the recent years. This paper tries to examine the effect of Chinese marine pollution on export of aquatic products in China. This paper utilizes cointegration test to estimate long-run equilibrium between marine pollution and fisheries products export. The results indicate that real exchange rate and income variable have positive effects and fish price has negative effect on China's fisheries export to Korea. However, marine pollution variable has no statistically significant effect on dependant variable. And according to the result of China's fisheries export to Japan, exchange rate has positive effect and both fish price and marine pollution variable have negative effects on export. Lastly, marine pollution and income level have effects on dependant variable in the case of Hong Kong, but exchange rate and price variable have no significant effect on aquatic products export from China to Hong Kong. In a word, marine pollution of China is a serious problem and it has negative effect on Chinese export of aquatic products.

Tectoridin, a Poor Ligand of Estrogen Receptor α, Exerts Its Estrogenic Effects via an ERK-Dependent Pathway

  • Kang, Kyungsu;Lee, Saet Byoul;Jung, Sang Hoon;Cha, Kwang Hyun;Park, Woo Dong;Sohn, Young Chang;Nho, Chu Won
    • Molecules and Cells
    • /
    • v.27 no.3
    • /
    • pp.351-357
    • /
    • 2009
  • Phytoestrogens are the natural compounds isolated from plants, which are structurally similar to animal estrogen, $17{\beta}$-estradiol. Tectoridin, a major isoflavone isolated from the rhizome of Belamcanda chinensis. Tectoridin is known as a phytoestrogen, however, the molecular mechanisms underlying its estrogenic effect are remained unclear. In this study we investigated the estrogenic signaling triggered by tectoridin as compared to a famous phytoestrogen, genistein in MCF-7 human breast cancer cells. Tectoridin scarcely binds to ER ${\alpha}$ as compared to $17{\beta}$-estradiol and genistein. Despite poor binding to ER ${\alpha}$, tectoridin induced potent estrogenic effects, namely recovery of the population of cells in the S-phase after serum starvation, transactivation of the estrogen response element, and induction of MCF-7 cell proliferation. The tectoridin-induced estrogenic effect was severely abrogated by treatment with U0126, a specific MEK1/2 inhibitor. Tectoridin promoted phosphorylation of ERK1/2, but did not affect phosphorylation of ER ${\alpha}$ at $Ser^{118}$. It also increased cellular accumulation of cAMP, a hallmark of GPR30-mediated estrogen signaling. These data imply that tectoridin exerts its estrogenic effect mainly via the GPR30 and ERK-mediated rapid nongenomic estrogen signaling pathway. This property of tectoridin sets it aside from genistein where it exerts the estrogenic effects via both an ER-dependent genomic pathway and a GPR30-dependent nongenomic pathway.

ANTIFUNGAL AND ANTIBACTERIAL ACTIVITIES OF SOME COMPOUNDS FROM MARINE NATURAL PRODUCTS

  • Chinh, Luu-Van;Dien, Pham-Huu;Minh, Chau-Van
    • Proceedings of the Korean Society of Applied Pharmacology
    • /
    • 1998.11a
    • /
    • pp.174-174
    • /
    • 1998
  • Twelve different derivatives were synthesised from chitin/chitosan[1, 2, 3]. Their structures have been determined by different physical methods. The bioassay screening on antifungal and antibacterial activities of all these compounds showed that most of them had significant activity and they can inhibite the growth of some fungi and bacterias : E. coli, S. pyogenes, F. oxysporum, P. oryzae, that caused the spoilage of fresh fruits and foods. Furthermore, all of these compounds are non-toxic (LD$\_$50/>50g/kg) and can be applied for food preservation.

  • PDF

Microbial Symbiosis in Marine Sponges

  • Lee, Yoo-Kyung;Lee, Jung-Hyum;Lee, Hong-Kum
    • Journal of Microbiology
    • /
    • v.39 no.4
    • /
    • pp.254-264
    • /
    • 2001
  • Sponges are host organisms for various symbiotic microorganisms such as archaea, bacteria, cyano-bacteria and microalgae. Sponges are also sources of a wide variety of useful natural products like cyto-toxins. antifouling agents, antibiotics, and anti-inflammatory and antiviral compounds, Symbiotic microorganisms is sponges can be sources of various natural products, because metabolites previously ascribed to sponges have recently been demonstrated to be biosynthesized by symbionts. If a symbiotic microorganisms from which some natural products are derived can be cultured, the microorganism could be used in a mass production of the bioactive comopounds. We summarize recent research on iso-lation and cultivation of sponge-symbiotic microorganisms and the symbiotic relationship.

  • PDF

Oral Pathogens and Their Antibiotics from Marine Organisms: A Systematic Review of New Drugs for Novel Drug Targets

  • Sehyeok Im;Jun Hyuck Lee;Youn-Soo Shim
    • Journal of dental hygiene science
    • /
    • v.24 no.2
    • /
    • pp.84-96
    • /
    • 2024
  • Background: Recent studies have elucidated the quorum-sensing mechanisms, biofilm formation, inter-pathogen interactions, and genes related to oral pathogens. This review aims to explore the recent expansion of drug targets against oral pathogens and summarize the current research on novel antibiotic substances derived from marine organisms that target oral pathogens. Methods: A comprehensive literature review summarized the novel mechanisms pertaining to quorum-sensing signal transmission systems, biofilm formation, and metabolite exchange in oral pathogens. The amino acid sequences of the 16 proteins identified as potential drug targets were systematically classified and compared across various oral microorganisms. Results: Through a literature review, we identified nine studies researching quorum sensing signaling inhibitors targeting oral pathogens. A comparison of the amino acid sequences of 16 potential drug targets in oral microorganisms revealed significant differences between oral pathogens and beneficial oral symbiotic microorganisms. These findings imply that it is possible to design drugs that can bind more selectively to oral pathogens. Conclusion: By summarizing the results of recent research on the signaling mechanisms that cause pathogenicity, new drug targets against oral pathogens were proposed. Additionally, the current status of developing new antibiotics for oral pathogens using recently developed quorum sensing inhibitors and natural products derived from marine organisms was introduced. Consequently, marine natural products can be used to develop drugs targeting new proteins in oral pathogens.

Overview of Fisheries Resources in Namibia

  • Endjala, Jason Tshuutheni
    • Journal of Marine Bioscience and Biotechnology
    • /
    • v.3 no.1
    • /
    • pp.31-37
    • /
    • 2008
  • Off the 1,572 km long coastline of Namibia lies known as the Benguela upwelling system, a very rich source of marine life supporting traditional and modern forms of fishery. Commercial fishing and fish processing is one of the fastest-growing sectors of the Namibian economy in terms of employment, export earnings, and contribution to GDP. The fishing industry has grown to the extent that it is currently Namibia's second biggest export earner of foreign currency after mining (90% of national output is marketed for export). In 2005, Namibia harvested about 552,164 tonnes of fish. The final value of processed products (export value) that year was around US$ 376.0 million. Besides the marine captured fisheries, Namibia also has a small but vibrant aquaculture sector. Inland captured fisheries exist in the north-east and north-west of Namibia where as commercial freshwater aquaculture of tilapia and catfish is also undertaken. The inland fisheries are mainly subsistence based and typically labour intensive, with low catch per unit effort. However the subsistence fisheries from these regions play a significant role in the lives of rural community. The domestic market for marine fish products is extremely limited due to the small size of the population (2 million). The fishing industry is a source of considerable employment for many Namibians. Huge potential to increase production exists in Namibia, unpolluted high quality marine waters, high natural primary productivity of the seawater, availability of inexpensive fish by-products from established fish processing sector for inclusion in wet aqua-feeds and well-established processing, packaging and marketing systems due to the marine capture fisheries that can be adopted for aquaculture purpose.

  • PDF

A Biostimulant Preparation of Brown Seaweed Ascophyllum nodosum Suppresses Powdery Mildew of Strawberry

  • Bajpai, Sruti;Shukla, Pushp Sheel;Asiedu, Samuel;Pruski, Kris;Prithiviraj, Balakrishnan
    • The Plant Pathology Journal
    • /
    • v.35 no.5
    • /
    • pp.406-416
    • /
    • 2019
  • Strawberry, an important fruit crop, is susceptible to a large number of pathogens that reduce fruit quality and productivity. In this study, the effect of a biostimulant prepared from Ascophyllum nodosum extract (ANE) (0.1%, 0.2%, and 0.3%) was evaluated on powdery mildew progression under greenhouse and field conditions. In the greenhouse, application of 0.2% ANE showed maximum reduction in powdery mildew progression as compared to the control. Forty-eight hour post-inoculation, foliar spray of 0.2% ANE reduced spore germination by 75%. Strawberry leaves sprayed with ANE showed higher total phenolic and flavonoid content in response to powdery mildew infection. Furthermore, application of ANE elicited defense response in strawberry plants by induction of defense-related enzymes, such as phenylalanine ammonia lyase, polyphenol oxidase, and peroxidase activity. In field conditions, foliar spray of 0.2% ANE showed a reduction of 37.2% of natural incidence of powdery mildew infection as compared to the control. ANE sprayed plant also reduces the severity of powdery mildew infection under natural conditions. These results indicate that application of ANE induces the strawberry plant's active defense against powdery mildew infection by induction of secondary metabolism and regulating the activities of defense-related enzymes.