The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Hiroshi Kawai - One of the best experts on this subject based on the ideXlab platform.
-
genetic diversity in Undaria pinnatifida laminariales phaeophyceae deduced from mitochondria genes origins and succession of introduced populations
Phycologia, 2006Co-Authors: Shinya Uwai, Wendy A Nelson, Kate F Neill, Wei Ding Wang, Luis E Aguilarrosas, Sung Min Boo, Taiju Kitayama, Hiroshi KawaiAbstract:S. Uwai, W. Nelson, K. Neill, W.D. Wang, L.E. Aguilar-Rosas, S.M. Boo, T. Kitayama and H. Kawai. 2006. Genetic diversity in Undaria pinnatifida (Laminariales, Phaeophyceae) deduced from mitochondri...
-
genetic diversity in Undaria pinnatifida laminariales phaeophyceae deduced from mitochondria genes origins and succession of introduced populations
Phycologia, 2006Co-Authors: Shinya Uwai, Wendy A Nelson, Kate F Neill, Wei Ding Wang, Luis E Aguilarrosas, Sung Min Boo, Taiju Kitayama, Hiroshi KawaiAbstract:Abstract To elucidate the genetic diversity of the brown alga Undaria pinnatifida in native and introduced populations worldwide, and to discuss the transoceanic introduction processes, we investigated the haplotype divergence of the mitochondrial loci of the coding region of cox3 and noncoding region between tatC and tLeu genes. In its native range (Japan, Korea and China), we found 27 haplotypes, which were classified into 4 genetic and biogeographical groups: (1) Northern Japan type, distributed in Hokkaido and Pacific northern Honshu; (2) Continental type, found in Korea and China; (3) Pacific central Japan type; and (4) Sea of Japan type. Among the introduced populations, European and Mexican populations agreed with the Northern Japan type. In Australia, the Tasmanian population agreed with the Sea of Japan type, whereas the Victorian population was of the Continental type. Very high diversities were found in New Zealand: 10 haplotypes were found (including 2 only in old herbarium specimens), includi...
Yong Il Park - One of the best experts on this subject based on the ideXlab platform.
-
structure and antitumour activity of fucoidan isolated from sporophyll of korean brown seaweed Undaria pinnatifida
Carbohydrate Polymers, 2010Co-Authors: Andriy Synytsya, Woojung Kim, Sung Min Kim, Radek Pohl, Alla Synytsya, Frantisek Kvasnicka, Jana Copikova, Yong Il ParkAbstract:Abstract Fucoidan from the sporophyll (Miyeokgui) of cultured Korean brown seaweeds Undaria pinnatifida (Miyeok) is interesting due to its various biological activities. This polysaccharide was isolated from raw material by dilute acid extraction, ballast alginates were removed by CaCl2 precipitation, and crude extract was purified by chromatography on DEAE–cellulose. Structure and composition of the fucoidan was characterised by various methods (organic elemental analysis, HPLC analysis of neutral sugars, FT-IR, FT-Raman, 1H and 13C NMR); molecular size and charge density were estimated by GPC and CITP. The polysaccharide was eluted by GPC as a single peak of approximate molecular weight of 1246 kDa. Miyeokgui fucoidan showed lower electrophoretic mobility (RSH ∼ 0.127) than carrageenans (0.096–0.100) and chondroitin sulphate A (0.103) but higher than alginate (0.170). Isolated polysaccharide contained α-fucose (50.9 mol%) and β-galactose (44.6 mol%) as main neutral sugar units; no uronic acid was observed. Sulphate (0.97 mol mol−1) and acetate (0.24 mol mol−1) esters were also found. Thus the polysaccharide was defined as O-acetylated sulphated galactofucan. The Miyeokgui fucoidan showed antitumour activity against PC-3 (prostate cancer), HeLa (cervical cancer), A549 (alveolar carcinoma), and HepG2 (hepatocellular carcinoma) cells, in a similar pattern to that of commercial fucoidan.
-
Anticoagulating activities of low-molecular weight fuco-oligosaccharides prepared by enzymatic digestion of fucoidan from the sporophyll of Korean Undaria pinnatifida
Archives of Pharmacal Research, 2010Co-Authors: Woojung Kim, Sung Min Kim, Yean-kyoung Koo, Mi-kyung Jung, Hye Ran Moon, Andriy Synytsya, Hye Sook Yun-choi, Yeong Shik Kim, Jae Kweon Park, Yong Il ParkAbstract:In spite of their potential as biologically active compounds, the high molecular mass and viscous natures of fucoidans have hampered their applications especially as a therapeutic agent. Herein the fucoidan-degrading enzyme activities were partially purified from the cultured cells of Sphingomonas paucimobilis PF-1 mainly by ammonium sulfate precipitation. This enzyme preparation degraded fucoidans from the Korean Undaria pinnatifida sporophyll into several low-molecular weight fuco-oligosaccharides (LMFOs) with less than 3,749 Da. The FTIR spectra of intact fucoidan and mixture of LMFOs (1,389∼3,749 Da) showed no significant structural difference except for about 10% reduced level of sulfate esters in LMFOs. The LMFOs have exerted strong anticoagulating activities at which the activated partial thromboplastin time (APTT) and thrombin time (TT) were significantly prolonged, although 3∼20 times weaker activities were observed than those of intact fucoidan. In addition, unlike intact fucoidan, LMFOs did not affect significantly to the prothrombin time (PT). These results suggest that the partially purified fucoidan-degrading enzyme preparation is valuable for the production of fuco-oligosaccharides having anticoagulating activities, and that the molecular weight and/or sulfate content of the fucoidan from the Korean Undaria pinnatifida sporophyll could be important factors for its anticoagulating activity.
-
isolation and characterization of marine bacterial strain degrading fucoidan from korean Undaria pinnatifida sporophylls
Journal of Microbiology and Biotechnology, 2008Co-Authors: Woojung Kim, Sung Min Kim, Yoonhee Lee, Hyun Guell Kim, Hyungkwon Kim, Seong Hoon Moon, Hyunhyo Suh, Kihyo Jang, Yong Il ParkAbstract:In spite of an increasing interest in fucoidans as biologically active compounds, no convenient commercial sources with fucoidanase activity are yet available. A marine bacterial strain that showed confluent growth on a minimal medium containing fucoidan, prepared from Korean Undaria pinnatifida sporophylls, as the sole carbon source was isolated and identified based on a 16S rDNA sequence analysis as a strain of Sphingomonas paucimobilis, and named Sphingomonas paucimobilis PF-1. The strain depolymerized fucoidan into more than 7 distinct lowmolecular- mass fucose-containing oligosaccharides, ranging from 305 to 3,749 Da. The enzyme activity was shown to be associated with the whole cell, suggesting the possibility of a surface display of the enzyme. However, a whole-cell enzyme preparation neither released the monomer Lfucose from the fucoidan nor hydrolyzed the chromogenic substrate p-nitrophenyl-alpha-L-fucoside, indicating that the enzyme may be an endo-acting fucoidanase rather than an alpha-L-fucosidase. Therefore, this would appear to be the first report on fucoidanolytic activity by a Sphingomonas species and also the first report on the enzymatic degradation of the Korean Undaria pinnatifida sporophyll fucoidan. Moreover, this enzyme activity may be very useful for structural analyses of fucose-containing polysaccharides and the production of bioactive fucooligosaccharides.
-
immunomodulating activity of a fucoidan isolated from korean Undaria pinnatifida sporophyll
Algae, 2007Co-Authors: Yungchoon Yoo, Woojung Kim, Sung Min Kim, Hyunhyo Suh, Soyeon Kim, Mikyung Chung, Joowoong Park, Kyungbok Lee, Yong Il ParkAbstract:A fucoidan, isolated from Korean Undaria pinnatifida spoprophyll (UP-F), was investigated for its immunomodulating activity on murine macrophages and splenocytes, and its activity was compared with that of fucoidan from Fucus vesiculosus (FV-F). Treatment of UP-F resulted in inhibition of the growth of murine macrophage RAW 264.7 cells, but its cytotoxicity was not observed in normal murine splenocytes. FV-F was shown to be highly cytotoxic to both immune cells, and its cytotoxic activity was higher than that of UP-F. Treatment of UP-F induced TNF-α in a dose-dependent manner from two types of macrophages, RAW 264.7 cells and murine peritoneal macrophages. The TNF-α-inducing activity of UP-F was higher than that of FV-F. UP-F also actively induced chemokines (RANTES and MIP-1α) from RAW 264.7 cells. Furthermore, treatment of UP-F gave rise to activation of murine splenocytes to produce cytokine (IL-6) and chemokines (RANTES and MIP-1α), showing significantly higher activity than that of FV-F. These results indicate that UP-F is less cytotoxic to immune cells than FV-F, and possesses immunomodulating activity to produce cytokines and chemokines from macrophages and splenocytes.
Takahisa Nakano - One of the best experts on this subject based on the ideXlab platform.
-
Effects of Undaria pinnatifida (wakame) on the human intestinal environment
Food Science Publisher, 2018Co-Authors: Keiko Yoshinaga, Reiko Maruya, Takashi Koikeda, Takahisa NakanoAbstract:Background: Undaria pinnatifida (wakame) is an edible seaweed. Wakame is a common food in the Japanese diet which exhibits various biological effects. Wakame is rich in dietary fiber. Despite the long history of its intake, changes in the intestinal environment following the ingestion of wakame are unclear. Methods: We examined the effect of a 2-week intake of wakame on defecation frequency and the intestinal microbiota of 22 healthy individuals suffering from low defecation frequency. The clinical trial was designed as an open-label study. Results: Defecation frequency, defined in terms of times per week, days per week, and volume per week significantly increased during the wakame intake period. Furthermore, based on terminal restriction fragment length polymorphism (T-RFLP), the fraction of bifidobacteria as a percentage of all fecal bacteria increased significantly during the wakame intake period. At the phylum, next-generation sequencing (NGS) revealed that the relative abundance of Actinobacteria after wakame intake significantly increased while the abundance of Bacteroidetes decreased. Moreover, species-level analyses revealed that the abundance of Bifidobacterium longum increased significantly after wakame intake. B. longum colony counts on wakame-containing medium were significantly higher than those on medium without wakame. Conclusion: These observations suggest that wakame intake improves intestinal environment and increases the fecal population of bifidobacteria, indicating that it may have prebiotic properties
-
anti influenza a virus characteristics of a fucoidan from sporophyll of Undaria pinnatifida in mice with normal and compromised immunity
Microbes and Infection, 2013Co-Authors: Kyoko Hayashi, Takahisa Nakano, Jungbum Lee, Toshimitsu HayashiAbstract:Undaria pinnatifida, an edible brown alga, contains fucoidan (FuC), a sulfated polysaccharide, that inhibited the in vitro replication of influenza A virus, and stimulated both innate and adaptive immune defense functions in virus-infected mice. In the present study, the effects of oral administration of FuC were evaluated on influenza virus infection in immunocompetent and immunocompromised mice, where the efficacy of FuC was demonstrated in reducing viral replication, decreasing weight loss and mortality, and prolonging survival. Oral FuC resulted in increased neutralizing antibody production in the mucosa and blood. In contrast, while suppressing virus yields in mice more markedly than FuC, oseltamivir significantly reduced the neutralizing antibody titers in both the mucosa and blood. In immunocompromised mice, drug-resistant viruses frequently recovered after oseltamivir treatment; no resistant viruses were isolated from FuC-treated mice. FuC could be a candidate for the development of new therapeutic options including its combination with neuraminidase inhibitors such as oseltamivir.
-
the role of nk cells in antitumor activity of dietary fucoidan from Undaria pinnatifida sporophylls mekabu
Planta Medica, 2006Co-Authors: Hiroko Maruyama, Hidekazu Tamauchi, Mariko Iizuka, Takahisa NakanoAbstract:Fucoidan from Mekabu (sporophyll of Undaria pinnatifida), a dietary alga, exerts antitumor activity possibly through enhancing the immune response. The present report describes the effects of dietary Mekabu fucoidan on the tumor growth of mouse A20 leukemia cells and on T cell-mediated immune responses in T cell receptor transgenic (DO-11 - 10 - Tg) mice. The animals were fed with a diet containing 1% Mekabu fucoidan (0.034 +/- 0.003 g/mouse/day) for 10 days and subcutaneously (s. c.) inoculated with A20 leukemia cells. Thereafter, the mice were fed with the diet containing fucoidan for 40 days. Mekabu fucoidan inhibited tumors by 65.4 %. We studied how the killer activities of T cell-mediated and natural killer (NK) cells are augmented in DO-11 - 10 mice fed with Mekabu fucoidan. The cytolytic activities of ovalbumin (OVA), which is specific against OVA-transfected A20 (OVA-A20) B lymphoma cells, and NK cells against YAC-1 were significantly enhanced in the mice fed with fucoidan compared with a basic diet. Thus, these findings suggested that Mekabu fucoidan mediates tumor destruction through Th1 cell and NK cell responses.
-
suppression of th2 immune responses by mekabu fucoidan from Undaria pinnatifida sporophylls
International Archives of Allergy and Immunology, 2005Co-Authors: Hiroko Maruyama, Minoru Hashimoto, Hidekazu Tamauchi, Takahisa NakanoAbstract:Background: We demonstrated that mekabu fucoidan obtained from Undaria pinnatifida (Up) sporophylls augments the type 1 T-helper (Th1) cell response in normal BALB/c mice. In this study, we examined the effects of the fucoidan of mekabu on the type 2 T-helper (Th2) response in bronchoalveolar lavage fluid (BALF) after ovalbumin (OVA) aerosol challenge. Methods: Mekabu fucoidan (50 mg/kg) was injected intraperitoneally into BALB/c mice for 4 days, and then the mice were sensitized with 50 µg/mouse of OVA plus alum (1 mg/mouse) 1 and 8 days later. The mice were challenged with OVA delivered using a nebulizer 7, 8 and 9 days after the second challenge with OVA plus alum. After 24 h, we assessed T cell responses in BALF by measuring the amount of Th2 cytokines (IL-4, IL-5, IL-13) and γ-interferon (IFN-γ) produced by Th1 cells. Results: The production of Th2 cytokines was suppressed (p Conclusions: The pulmonary inflammation was relieved by mekabu fucoidan, which also downregulated Th2-dominated responses. These results indicate that mekabu fucoidan modulates Th2 responses and might be useful for treating allergic inflammation.
-
novel antiviral fucoidan from sporophyll of Undaria pinnatifida mekabu
Chemical & Pharmaceutical Bulletin, 2004Co-Authors: Jungbum Lee, Takahisa Nakano, Kyoko Hayashi, Minoru Hashimoto, Toshimitsu HayashiAbstract:Structural characterization and antiviral activities of fucoidan from sporophyll of Undaria pinnatifida (Mekabu) was examined. The fucoidan was composed of fucose and galactose with an approximately ratio of 1.0:1.1. Degree of substitution of sulfate was 0.72 and its apparent molecular weight was 9,000. Methylation analyses showed that fucoidan had various sugar linkages, and revealed that the fucoidan might have complicated structure. This fucoidan showed potent antiviral activities against herpes simplex virus type 1 (HSV-1), HSV-2, and human cytomegalovirus.
Maria Luz Piriz - One of the best experts on this subject based on the ideXlab platform.
-
population features of the invasive kelp Undaria pinnatifida phaeophyceae laminariales in nuevo gulf patagonia argentina
Journal of the Marine Biological Association of the United Kingdom, 2008Co-Authors: Graciela N Casas, Maria Luz Piriz, Elisa R ParodiAbstract:The invasive kelp Undaria pinnatifida was observed for the first time in the Nuevo Gulf (Patagonia, Argentina) in December 1992. At the present time, with the exception of sandy bottoms, the coasts of the Nuevo Gulf are almost entirely colonized. From October 1997 to February 2000, the characteristics of this population, i.e. the relationships between morphological features and seawater temperature, the seasonality in sporophyll development and the proportions of different reproductive stages during its life cycle, were analysed. The observations confirmed that the maximal mean densities of sporophytes (149.1 plants m −2 ) occurred in winter while the mean tallest sporophytes (88.5 cm) and the mean highest biomass (16501 g m −2 ) were registered in spring and at the beginning of the summer. Coexisting juvenile and mature sporophytes were found. Sporophylls showed also seasonal characteristics, with maximal width in summer. Manipulative experiments conducted for testing the recruitment pattern of Undaria pinnatifida confirmed that the presence of juvenile individuals was uninterrupted. Thus, in this paper, we denote that U. pinnatifida has a constant recruitment, together with high reproductive rates, which are some of the characteristics of an introduced species, which explains why they became a highly invasive species or ‘pest species’, with negative environmental and economic effects.
-
the invasive kelp Undaria pinnatifida phaeophyceae laminariales reduces native seaweed diversity in nuevo gulf patagonia argentina
Biological Invasions, 2004Co-Authors: Graciela N Casas, Ricardo Augusto Scrosati, Maria Luz PirizAbstract:The kelp Undaria pinnatifida(Phaeophyceae) is a seaweed native to northeast Asia, but during the last two decades, it has been accidentally or intentionally introduced in several temperate coasts worldwide. In central Patagonia (Argentina), this species was first detected in late 1992, and it is progressively spreading from the point of introduction. Through a manipulative experiment involving Undaria removal in 2001, we found that its presence is associated with a dramatic decrease in species richness and diversity of native seaweeds in Nuevo Gulf. Future prospects are worrisome, as, in addition to the negative impact from a biodiversity viewpoint, native commercial macroalgae and invertebrates might also be affected.
Tifeng Shan - One of the best experts on this subject based on the ideXlab platform.
-
genetic analysis of a recently established Undaria pinnatifida laminariales alariaceae population in the northern wadden sea reveals close proximity between drifting thalli and the attached population
European Journal of Phycology, 2019Co-Authors: Tifeng Shan, Shaojun Pang, Xuemei Wang, Jessica Schiller, Dagmar Lackschewitz, Jason M Hallspencer, Kai BischofAbstract:Undaria pinnatifida, a kelp species native to East Asia, has become cosmopolitan and drawn increasing attention due to its worldwide spread in recent decades. Floating fragments of this alga were f...
-
selection of reference genes for real time rt pcr normalization in brown alga Undaria pinnatifida
Journal of Applied Phycology, 2019Co-Authors: Haishu Huang, Tifeng Shan, Shaojun PangAbstract:Quantitative real-time PCR (qRT-PCR) has become widely used method for detecting gene expression of an organism at different developmental stages or under various stressful environmental conditions. Finding reference genes is a prerequisite in this process. In this research, we investigated the expression stability of eight candidate genes in the brown alga Undaria pinnatifida, including EF1α (elongation factor 1-alpha), eEF1β (eukaryotic elongation factor-1 B beta), RPL35 (60S ribosomal protein L35-3), GAPDH (glyceraldehyde-3-phosphatedehydrogenase), RPS17 (40S ribosomal protein S17), LHCP (light-harvesting complex protein), ribH (6,7-dimethyl-8-ribityllumazine synthase), and ilvC (ketol-acid reductoisomerase). The haploid male and female gametophytes at different stages, as well as the diploid sporophytes treated with different abiotic factors were analyzed by geNorm and NormFinder software. It was found that eEF1β and ribH could be used as the most stable reference genes in studies of gender or developmental gene expression in the gametophytes. As for the detection of gene expression in the sporophytes, eEF1β and ribH were recommended as the most suitable reference genes for irradiance treatment, eEF1β and RPL35 for temperature treatment, while EF1α and LHCP for nutrition treatment. These results will enable us to go further for quantifying gene expression study at transcript level in U. pinnatifida.
-
existence of an intact male life cycle offers a novel way in pure line crossbreeding in the brown alga Undaria pinnatifida
Journal of Applied Phycology, 2017Co-Authors: Shaojun Pang, Tifeng ShanAbstract:Hermaphroditic gametophyte production and an intact male life cycle were investigated in Undaria pinnatifida. Zoospore-derived hermaphroditic gametophyte could give rise to male sporophytes which showed the same morphological appearance but with smaller biomass than normal cultivated sporophytes. Male sporophytes were shown to discharge only male zoospores. In this investigation, male spores derived from the male sporophytes and female spores derived from female parthenosporophytes were crossed to produce the hybrid sporophytic offspring. The latter contained both alleles of homozygous parental sporophytes when analyzed by use of eight polymorphic microsatellite markers, further confirming the success of cross. Thus, line crossing by use of unisexual sporophytes will be expected to replace unisexual gametophyte line crossing in breeding practice in the future in this commercially farmed seaweed.
-
de novo transcriptome analysis of the gametophyte of Undaria pinnatifida phaeophyceae
Journal of Applied Phycology, 2015Co-Authors: Tifeng Shan, Shaojun Pang, Jing Li, Xia LiAbstract:Undaria pinnatifida has received increasingly more attention worldwide in recent years because, on one hand, it is of high economic importance in East Asian countries and, on the other hand, it is listed as an invasive species in many other countries. Unfortunately, fundamental research has been hindered by the lack of available genomic information on this species. In this study, the transcriptome of the gametophyte of U. pinnatifida was sequenced and de novo assembly was conducted. Using an Illumina sequencing platform, 129 million clean reads were acquired. After assembly, a total of 44,264 unigenes were obtained and the average and N50 length of them were 1,321 and 2,059 nucleotides (nt), respectively. It was predicted that 44,183 (99.8 %) unigenes had the open reading frames (ORF). Twenty-two thousand six hundred fifty-nine unigenes shared homology to existing protein sequences in non-redundant (Nr) database. Fifteen thousand ninety-eight unigenes had significant similarity with the deposited sequences in SwissProt database. A total of 13,282 unigenes were assigned at least one gene ontology (GO) term, and 6,683 unigenes were classified into 25 Cluster of Orthologous Groups (COG) categories. Functional annotation with the Kyoto Encyclopedia of Genes and Genomes (KEGG) database assigned 4,200 unigenes to 114 pathways. Putative genes coding for the key enzymes involved in biosynthetic pathway of fucoidan, alginate, mannitol, and laminarin, as well as those encoding different kinds of heat shock protein families, were identified. Moreover, a total of 14,955 SSR loci were identified in the unigenes longer than 1,000 nt, and tentative primers were designed for 7,405 simple sequence repeat (SSR) loci. To our knowledge, this is the first data set for U. pinnatifida transcriptome and will lay the foundation for further studies on this species.
-
zoospore derived monoecious gametophytes in Undaria pinnatifida phaeophyceae
Chinese Journal of Oceanology and Limnology, 2014Co-Authors: Jing Li, Shaojun Pang, Tifeng ShanAbstract:The annual life cycle of the brown seaweed Undaria pinnatifida (Harvey) Suringer comprises a macroscopic diploid sporophyte stage and a microscopic haploid gametophyte stage. In 2011, an unusual zoospore-derived monoecious gametophyte isolate (designated as line 10-5-3) of U. pinnatifida was observed. To understand this phenomenon, a comprehensive screening of eighty-two previously identified male gametophyte cultures, isolated from three randomly selected cultivars (lines 10, 7, and 5) was performed. Thirty-six of the isolates developed both antheridia and oogonia on the same filamentous fragment in a standard gametogenesis test (SGT: 18A degrees C, 60 mu mol photons/(m(2)center dot s)). Selfing of the monoecious gametophyte or crossing it with a normal male gametophyte both gave rise to morphologically normal sporophytic offspring. However, crossing resulted in a much higher fertilization rate (89.7%). The hybrid and selfed sporophytic offspring were grown to maturity in flow tanks at an ambient temperature of 10-18A degrees C over a period of 69 days. Active zoospores were released from both types of mature sporophylls. The majority of these developed into male gametophytes, while 15%-20% developed into the observed monoecious structures on the same filament. Using PCR amplification it was found that all the monoecious gametophyte isolates and the sporophytic offspring resulting from the selfing and crossing lacked the femalelinked microsatellite sequence (a part of the locus Up-AC-2A8, GenBank accession No. AY738602.1), indicating their male nature. U. pinnatifida is an invasive species in some regions and the implications of the above findings for this species in nature are briefly discussed.
