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SUMMARY: Lithophyllum is a cosmopolitan coralline algal genus with 12 species currently recognized in Japan based on modern morpho‐anatomical taxonomic concepts primarily characterized by having uniporate tetrasporangial and bisporangial conceptacles, the presence of secondary pit‐connections between cells of adjacent filaments and a dimerous thallus construction with a single basal layer of predominantly non‐palisade cells. In the present study, we describe Lithophyllum nagaokaense sp. nov. based on a combination of molecular and morpho‐anatomical data of specimens from the temperate waters of Japan. The new species forms both attached epilithic thalli and free‐living rhodoliths. Phylogenetic analyses of psbA, rbcL and COI markers resolved L. nagaokaense as an independent species. Morpho‐anatomically, L. nagaokaense resembles Lithophyllum johansenii, originally described from Australia, but distinguished from the latter by the absence of enlarged angular cells occluding pore canals of tetrasporangial conceptacle chambers. Lithophyllum nagaokaense shared a fruticose morphology with Lithophyllum kaiseri, Lithophyllum kuroshioense, Lithophyllum neo‐okamurae, Lithophyllum okamurae, and Lithophyllum pygmaeum from Japan. Of these, L. nagaokaense is the most similar to L. neo‐okamurae in having attached and free‐living thalli with encrusting and warty to lumpy growth forms bearing knobby protuberances that are dichotomously branched or anastomosing. The new species is distinct from other Japanese fruticose species collectively by five tetrasporangial conceptacle chamber characters and the absence of trichocytes. A taxonomic key for identifying Japanese fruticose species is provided. This is the fifth Lithophyllum species and the third rhodolith‐forming species verified by DNA sequencing to be found in Japan. [ABSTRACT FROM AUTHOR]

Rice fields are characterized by high algal production and dense mats of filamentous green algae, and they function as habitats for various aquatic organisms. However, how algal production supports the secondary production of aquatic consumers in rice fields has not been assessed. Herein, aquatic food web structures in two adjacent rice fields in northeastern Japan were examined using carbon and nitrogen stable isotope analyses. Filamentous algae often showed higher δ13C values (mean, −23.1‰ to −21.4‰) than other organic matter sources, including particulate organic matter, benthic microalgae, and soil organic matter (−30.1‰ to −25.4‰). A δ13C‐based isotopic mixing model estimated that among 19 taxa of herbivores and omnivores, most taxa depended on filamentous algae‐derived carbon (ca. >30%). Particularly, Peltodytes intermedius larvae, a specialist feeder for filamentous algae, showed the highest reliance (mean, 66.7%–80.0%). The microcrustacean, Ostracoda sp. also utilized a diet consisting of a substantial proportion of filamentous algae‐derived carbon (57.6%). Seven out of 10 carnivorous taxa showed reliance on filamentous algae‐derived carbon by >30%. Particularly, larvae of beetles (Berosus sp., Enochrus sp., and Hydrochara affinis) showed the highest reliance (40.2%–44.3%). They could assimilate filamentous algae‐based carbon by consuming herbivores, such as P. intermedius. Because fresh filamentous green algae were eaten less by aquatic consumers, the herbivores could consume decomposed filamentous algae rather than fresh ones. Our results suggest that filamentous algae are one of the major organic matter sources supporting secondary production in rice field food webs. [ABSTRACT FROM AUTHOR]

Macrophytes, comprising aquatic vascular plants, bryophytes, and macroalgae, including charophytes, are crucial components of lake ecosystems. Their diversity affects ecosystem functions and services, and they are sensitive to environmental changes, making them effective indicators of lake health. Historical records of macrophyte species composition are essential for evaluating environmental changes and conservation goals. In this study, we compiled a comprehensive database of macrophytes, along with lake and survey information from the literature, providing a historical record of macrophyte biodiversity for lakes in Japan. This database enables the analysis of changes in the flora of Japanese lakes and fluctuations in species distribution, facilitating future monitoring. The complete dataset for this abstract published in the Data Article section of the journal is available in MetaCat in JaLTER at http://db.cger.nies.go.jp/JaLTER/metacat/metacat/ERDP-2024-02.1/jalter-en. [ABSTRACT FROM AUTHOR]

SUMMARY: The effects of four stressors, temperature, irradiance, desiccation and salinity, on the photochemical efficiency (ΔF/Fm′) of an edible green alga, Caulerpa chemnitzia var. laetevirens from Kagoshima, Japan, were determined for optimizing cultivation and shipping environments using a pulse amplitude modulation‐chlorophyll fluorometer. The ΔF/Fm′ remained stable at 24–34°C during the 3‐day temperature exposures ranging from 8 to 36°C; however, it dropped at higher and lower temperatures. During continuous exposure for 6 h to irradiance levels of 400 (low) and 1000 (high) μmol photons m−2 s−1 at 16, 24 and 32°C, the decrease in ΔF/Fm′ was pronounced at high irradiance. Moreover, ΔF/Fm′ also dropped at 16°C even under low irradiance, suggesting the occurrence of low temperature–light stress. Desiccation experiments under 50% humidity and up to 5 h of aerial exposure at 24°C and dim light (20 μmol photons m−2 s−1) indicated that ΔF/Fm′ was well tolerated within 1 h of desiccation; however, it dropped quickly as the desiccation period prolonged, suggesting that, if more than 20% of the interior water was lost, ΔF/Fm′ dropped progressively. However, during a similar experiment up to 14 days of aerial exposure under saturated humidity (99%) and dim light (12:12 h light/dark photocycle), as the interior water of the frond was maintained because of the saturated humidity, ΔF/Fm′ appeared to be well maintained for up to 5 days. Similar to desiccation, this alga exhibited stenohaline characteristics (30–40 psu) under the salinity gradient of 0–80 psu for up to 7 days of culture at 24°C and under dim light (12:12 h light/dark). In conclusion, this alga can be cultivated by modifying the techniques used for cultivating Japanese Caulerpa lentillifera and adjusting its environment accordingly. To ensure appropriate shipping conditions, it is essential to maintain saturated humidity in a plastic container at room temperature. [ABSTRACT FROM AUTHOR]

Rhabdamoeba marina is a unique and poorly reported amoeba with an uncertain phylogenetic position. We successfully cultured R. marina from coastal seawater in Japan and performed a molecular phylogenetic analysis using the small subunit ribosomal RNA (SSU rRNA) gene sequence. Our phylogenetic analysis showed that R. marina branched as a basal lineage of Chlorarachnea, a group of marine photosynthetic algae belonging to the phylum Cercozoa within the supergroup Rhizaria. By comparing the ecological and morphological characteristics of R. marina with those of photosynthetic chlorarachneans and other cercozoans, we gained insight into the evolution and acquisition of plastids in Chlorarachnida. [ABSTRACT FROM AUTHOR]

Ishimozuku (Sphaerotrichia firma) is one species of edible brown algae in Japan. The lipids contain rich of fucoxanthin and n-3 unsaturated fatty acids. This study analyzed dietary Ishimozuku lipid components and the effects on fatty liver and intestinal metabolite component production in obese model mice. Fatty acid composition and fucoxanthin contents of Ishimozuku lipids were analyzed by gas chromatography (GC) and high performance liquid chromatography (HPLC) analysis. Ishimozuku lipids contained fucoxanthin about 44.71 ± 0.02 mg/g. KK-Ay mice were fed with high-fat diet (Control) and a high-fat diet + 0.5% Ishimozuku lipid diet (Ishimozuku) for 4 weeks. Liver triglyceride contents and serum triglyceride concentrations were significantly lower in the Ishimozuku group than in the Control group. Results show that acetyl-CoA carboxylase (ACC) and stearoyl-CoA desaturase (SCD-1) mRNA expression were suppressed in the livers of Ishimozuku group mice. Furthermore, short chain fatty acid amounts in the cecal contents were greater in the Ishimozuku group mice. These results suggest that dietary Ishimozuku lipid components suppress liver lipid accumulation. Results also indicate Ishimozuku lipid components improve the balance of the intestinal microflora, which is disturbed by a high fat diet, and which promotes short chain fatty acid accumulation in the intestine. That accumulation is related to lipid and glucose metabolism. [ABSTRACT FROM AUTHOR]

Introduction: Microbial communities are important components of glacier and snowpack ecosystems that influence biogeochemical cycles and snow/ice melt. Recent environmental DNA surveys have revealed that chytrids dominate the fungal communities in polar and alpine snowpacks. These could be parasitic chytrids that infect snow algae as observed microscopically. However, the diversity and phylogenetic position of parasitic chytrids has not been identified due to difficulties in establishing their culture and subsequent DNA sequencing. In this study, we aimed to identify the phylogenetic positions of chytrids infecting the snow algae, Chloromonas spp., bloomed on snowpacks in Japan. Methods: By linking a microscopically picked single fungal sporangium on a snow algal cell to a subsequent sequence of ribosomal marker genes, we identified three novel lineages with distinct morphologies. Results: All the three lineages belonged to Mesochytriales, located within "Snow Clade 1", a novel clade consisting of uncultured chytrids from snow-covered environments worldwide. Additionally, putative resting spores of chytrids attached to snow algal cells were observed. Discussion: This suggests that chytrids may survive as resting stage in soil after snowmelt. Our study highlights the potential importance of parasitic chytrids that infect snow algal communities. [ABSTRACT FROM AUTHOR]

SUMMARY: The subtidal brown algal species Sporochnus dotyi Brostoff (Sporochnales, Phaeophyceae), which has been regarded as a Hawaiian endemic, is reported from Kushimoto, Kii Peninsula, Pacific coast of central Honshu, Japan, for the first time outside Hawai'i. The species grew on subtidal rocks ca. 5–20 m deep attached by a small conical holdfast. The erect thalli were 5–30 cm high, terete, robust and alternately branched in 1–2 orders. When mature, pedicellate receptacles developed on the branches, and formed elliptical sori 1 mm long with a pedicel 3–5 mm long. The apical parts of the thalli and the receptacles were terminated with a tuft of simple assimilatory filaments of up to 4 mm long and showed prominent green to yellow underwater iridescence. Reproductive filaments (paraphyses) were densely packed, simple, up to 200 μm long and bore 4–6 mostly unilateral unilocular zoidangia 20–22 μm long and 5–6 m in diameter. In the genetic analyses, the Sporochnus alga from Kushimoto had partial rbcL sequence identical to S. dotyi from Hawai'i. The cox3 phylogeny revealed that this alga formed a fully supported clade with S. dotyi. Therefore, we identified the alga from Kushimoto as S. dotyi. This finding of S. dotyi from Japan, together with the recent reports of the mesophotic macroalgae Ryuguphycus kuaweuweu (=Umbraulva kuaweuweu), Ulva iliohaha and Newhousia imbricata from various localities in the Pacific Ocean including Japan, suggest closer biogeographical connections of subtidal/mesophotic macroalgae in the Pacific than previously recognized. [ABSTRACT FROM AUTHOR]

SUMMARY: The effect of temperature, light‐spectrum, desiccation and salinity gradients on the photosynthesis of a Japanese subtidal brown alga, Sargassum macrocarpum (Fucales), was determined using a pulse amplitude modulation‐chlorophyll fluorometer and dissolved oxygen sensors. Temperature responses of the maximum (Fv/Fm in darkness) and effective (ΔF/Fm′ at 50 μmol photons m−2 s−1; = ΦPSII) quantum yields during 6‐day culture (4–36°C) remained high at 12–28°C, but decreased at higher temperatures. Nevertheless, ΔF/Fm′ also dropped at temperatures below 8°C, suggesting light sensitivity under chilling temperatures because Fv/Fm remained high. Photosynthesis–irradiance responses at 24°C under red (660 nm), green (525 nm), blue (450 nm) and white light (metal halide lamp) showed that maximum net photosynthesis under blue and white light was greater than under red and green light, indicating the sensitivity and photosynthetic availability of blue light in the subtidal light environment. In the desiccation experiment, samples under aerial exposure of up to 8 h under dim‐light at 24°C and 50% humidity showed that ΔF/Fm′ quickly declined after more than 45 min of emersion; furthermore, ΔF/Fm′ also failed to recover to initial levels even after 1 day of rehydration in seawater. Under the emersion state, the ΔF/Fm′ remained high when the relative water content (RWC) was greater than 50%; in contrast, it quickly dropped when the RWC was less than 50%. When the RWC was reduced below 50%, ΔF/Fm′ did not return to initial levels, regardless of subsequent re‐hydration, suggesting a low capacity of photosynthesis to recover from desiccation. The stenohaline response of photosynthesis under 3‐day culture is evident, given that ΔF/Fm′ declined when salinity was beyond 20–40 psu. Adaptation to subtidal environments in temperate waters of Japan can be linked to these traits. [ABSTRACT FROM AUTHOR]

Snow algae are photosynthetic microbes growing on snowpacks and are commonly observed in mountain areas in Japan. In this study, we report the snow algal blooms observed in Mt. Echigo-Komagatake located in Niigata prefecture, Japan. Field investigation was conducted in late June of 2021 on a snow patch located in an alpine zone at an altitude of 2000 m above sea level. Patches of snow with red, green, or brown color were observed on the snowpack. Microscopic observation showed that the colored snow contained various morpho-types of snow algal cells, which appeared to be similar to those previously reported in Japan. The algal communities of the colored snow were mostly dominated by red spherical cells, which is likely to be Sanguina nivaloides, and consistent with those of the red snow reported in other alpine snowpacks in Japan. However, some samples showed a community consisting of various cell types, including multiple species of genus Chloromonas. The difference in community structure may be due to distance from vegetation around the snow patch, nutrient conditions of the snow, and/or growth period of the algae. The snow algal blooms of Mt. Echigo-Komagatake can be characterized by the appearance of various colors and algal communities on a snowpack. [ABSTRACT FROM AUTHOR]

Background: The obesity epidemic has become a serious public health problem in many countries worldwide. Seaweed has few calories and is rich in active nutritional components necessary for health promotion and disease prevention. The aim of this study was to investigate the effects of the Campylaephora hypnaeoides J. Agardh (C. hypnaeoides), an edible seaweed traditionally eaten in Japan, on high-fat (HF) diet-induced obesity and related metabolic diseases in mice. Methods: Male C57BL/6J mice were randomly divided into the following groups: normal diet group, HF diet group, HF diet supplemented with 2% C. hypnaeoides, and HF diet supplemented with 6% C. hypnaeoides. After 13 weeks of treatment, the weight of the white adipose tissue and liver, and the serum levels of glucose, insulin, adipokines, and lipids were measured. Hepatic levels of adipokines, oxidant markers, and antioxidant markers were also determined. Insulin resistance was assessed by a glucose tolerance test. Polysaccharides of C. hypnaeoides were purified and their molecular weight was determined by high-performance seize exclusion chromatography. The anti-inflammatory effects of purified polysaccharides were evaluated in RAW264.7 cells. Results: Treatment of HF diet-induced obese mice with C. hypnaeoides for 13 weeks suppressed the increase in body weight and white adipose tissue weight. It also ameliorated insulin resistance, hyperglycemia, hepatic steatosis, and hypercholesterolemia. The ingestion of an HF diet increased serum levels of malondialdehyde (MDA), tumor necrosis factor α (TNF-α), and monocyte chemoattractant protein-1 (MCP-1), while it decreased serum adiponectin levels. In the liver, an HF diet markedly increased the MDA, TNF-α, and interleukin-6 (IL-6) levels, while it decreased glutathione and superoxide dismutase. These metabolic changes induced by HF diet feeding were ameliorated by dietary C. hypnaeoides. Purified polysaccharides and ethanol extract from C. hypnaeoides inhibited the lipopolysaccharide-induced overproduction of nitric oxide and TNF-α in macrophage RAW264.7 cells. Conclusions: The present results indicated that C. hypnaeoides was able to alleviate HF diet-induced metabolic disorders, including obesity, hyperglycemia, hepatic steatosis, and hypercholesterolemia by attenuating inflammation and improving the antioxidant capacity in mice. Polysaccharides and polyphenols may be involved in these beneficial effects of C. hypnaeoides. [ABSTRACT FROM AUTHOR]

This study conducted an integrated approach combining monitoring and risk assessment of pesticides in Kurose River and its catchment area, Japan. Water samples (n = 168) were collected every month for 1 year (March 2016 to February 2017). Pesticides (cyanazine, simetryn, fenarimol, isoprothiolane, and diazinon) were extracted by Sep‐Pack C18 cartridges and analyzed using a reversed‐phase HPLC‐UV system. The pesticides were also determined in non‐target organisms Red algae (Audouinella sp.) and diatoms (Cocconeis placentula) from the river. Based on the residual concentrations, an ecotoxicological risk assessment was conducted using the risk quotient (RQ) index. The human health carcinogenic and non‐carcinogenic risk assessments were evaluated using hazard quotients (HQ). Results showed that cyanazine was the most commonly detected (64%), followed by simetryn (58%), and diazinon (57%) in all the sample sites (n = 12). Except for isoprothiolane, the pesticides were highest in spring followed by summer, autumn and winter. Based on extreme values (ex), non‐acceptable ecotoxicological risk was obtained for diazinon (RQex = 21.317), cyanazine (RQex = 3.129), simetryn (RQex = 8.577) and fenarimol (RQex = 10.855), while that of isoprothiolane (RQex = 0.013) was negligible. Based on the HQ estimates, all the pesticides were below the threshold value of 1, hence pose no significant health risks to humans. Practitioner Points: Pesticides affect non‐target organisms in rivers and other aquatic systemsPesticides were frequently detected in spring and summer and accumulated in red algae and diatomThe detected pesticides posed high ecotoxicological and human health risks [ABSTRACT FROM AUTHOR]

Photographs of Cladosiphon okamuranus and the cultivation nets during the cultivating period in Okinawa. Center: Thalli of C. okamuranus cultivated in 8 different places in Okinawa Prefecture, Japan. Although morphologies of algae appear to be similar during sample collection, detail observation revealed some variations among them in size and level of branching. Cell wall structure of these thalli is reported by Awanthi et al. in this issue. [ABSTRACT FROM AUTHOR]

Single‐gene markers, such as the mitochondrial cox1, microsatellites, and single‐nucleotide polymorphisms are powerful methods to describe diversity within and among taxonomic groups and characterize phylogeographic patterns. Large repositories of publicly‐available, molecular data can be combined to generate and evaluate evolutionary hypotheses for many species, including algae. In the case of biological invasions, the combination of different molecular markers has enabled the description of the geographic distribution of invasive lineages. Here, we review the phylogeography of the widespread invasive red macroalga Agarophyton vermiculophyllum (synonym Gracilaria vermiculophylla). The cox1 barcoding provided the first description of the invasion history and hinted at a strong genetic bottleneck during the invasion. Yet, more recent microsatellite and SNP genotyping has not found evidence for bottlenecks and instead suggested that genetically diverse inocula arose from a highly diverse source population, multiple invasions, or some mix of these processes. The bottleneck evident from cox1 barcoding likely reflects the dominance of one mitochondrial lineage, and one haplotype in particular, in the northern source populations in Japan. Recent cox1 sequencing of A. vermiculophyllum has illuminated the complexity of phylogeographic structure in its native range of the northwest Pacific Ocean. For example, the western coast of Honshu in the Sea of Japan displays spatial patterns of haplotypic diversity with multiple lineages found together at the same geographic site. By consolidating the genetic data of this species, we clarify the phylogenetic relationships of a well‐studied macroalga introduced to virtually every temperate estuary of the Northern Hemisphere. [ABSTRACT FROM AUTHOR]

Snow algae are photosynthetic microbes that inhabit the melting snow surface in alpine and polar regions. We analyzed the pigment and species composition of colored snow collected on Mt. Tateyama in Japan during the melting seasons of 2015 and 2016. High-performance liquid chromatographic analyses of the pigments extracted from the colored snow showed that their composition varied within the study area and were classified into four types: Type A (astaxanthin-monoester dominant), Type B (medium astaxanthin-monoester content), Type C (abundant primary carotenoids and free-astaxanthin), and Type D (abundant primary carotenoids and astaxanthin diesters). Types A and B were most commonly observed in the study area, whereas Types C and D appeared only at specific sites. Analysis of the 18S ribosomal RNA (18S rRNA) gene revealed six major amplicon sequence variants (ASVs) of snow algae, belonging to the Sanguina, Chloromonas , and Chlainomonas groups. The relative abundance of the algal ASVs showed that Sanguina was dominant (>48%) in both Types A and B, suggesting that the difference in astaxanthin abundance between the two types was caused by the production of pigments in the algal cells. The algal community structures of Types C and D differed from those of Types A and B, indicating that the primary carotenoids and astaxanthin diesters were derived from certain algal species in these types. Therefore, astaxanthin-rich Sanguina algae mostly induced the red snow that appeared widely in this alpine area; however, they were partially dominated by Chloromonas or Chlainomonas algae, causing different pigment compositions. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 (COVID-19) pandemic in Japan is not as disastrous as it is in other Western countries, possibly because of certain lifestyle factors. One such factor might be the seaweed-rich diet commonly consumed in Japan. COVID-19 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which binds to angiotensin-converting enzyme 2 (ACE2) on the cell surface and downregulates ACE2, likely elevating the ratio of angiotensin-converting enzyme (ACE) to ACE2. The overreaction of the immune system, combined with the cytokine storm and ACE dominance, is purported to cause the condition of COVID-19 patients to deteriorate rapidly. Dietary seaweeds contain numerous components, including ACE inhibitory peptides, soluble dietary fibers (eg, fucoidan, porphyran), omega-3 fatty acids, fucoxanthin, fucosterol, vitamins D3 and B12, and phlorotannins. These components exert antioxidant, anti-inflammatory, and antiviral effects directly as well as indirectly through prebiotic effects. It is possible that ACE inhibitory components could minimize the ACE dominance caused by SARS-CoV-2 infection. Thus, dietary seaweeds might confer protection against COVID-19 through multiple mechanisms. Overconsumption of seaweeds should be avoided, however, as seaweeds contain high levels of iodine. [ABSTRACT FROM AUTHOR]

Fungi-algae interactions, such as lichen-forming fungi and parasitic chytrids on phytoplankton, are common in ecosystems. In contrast, interactions between filamentous fungi and soil algae that can be observed with the naked eye have been given little attention and remain unexplored. Here, we report a fungus that was associated with a visible symptom of dead algae on a soil surface in Sugadaira-kogen, Nagano, central Japan. Acremonium-like conidiophores were growing on vesicles and dead bodies of a yellow-green alga, Botrydium granulatum. The fungus was identified as Emericellopsis mirabilis based on its morphology by microscopic observation, phylogenetic analysis, and the similarity of the isolation substrate with the first description of the species. Co-culture experiments showed a filamentous cell differentiation of the alga by the fungus, but no harmful or beneficial effects on algal growth. Therefore, we speculate that E. mirabilis is a facultative parasite of B. granulatum under natural conditions. [ABSTRACT FROM AUTHOR]

Astaxanthin (AST), a naturally-occurring keto-carotenoid found in several species of bacteria and microalgae, has demonstrated diverse biological activities in vitro and in vivo. There is growing commercial interest in the application of astaxanthin in nutraceuticals and cosmeceuticals, due to its purported photoprotective, DNA repair, antioxidant, and anti-inflammatory benefits. This systematic review therefore aimed to summarize current clinical evidence on the effects of astaxanthin supplementation on skin health. Using the following combinations of broad Major Exploded Subject Headings (MesH) terms or text words [astaxanthin OR AST OR ASX OR carotenoid OR xanthophyll] AND [skin OR derm*], a comprehensive search of PubMed, EMBASE, Medline, Clinicaltrials.gov, and Google Scholar databases found a total of eleven clinical studies. There were six randomized, placebo-controlled, double-blind trials, while the rest were prospective, open-label studies. In many of the randomized, controlled trials reviewed, AST supplementation improved skin texture, appearance (wrinkles), and moisture content at the end of the study period. AST also appeared to protect against UV-induced skin damage. No serious adverse events were reported in any of the studies. However, most available studies had a relatively small sample size and were conducted on healthy Japanese females. Many of the studies were also funded by commercial entities, with potential conflicts of interests. This was difficult to account for in our analyses. Overall, there is some clinical data to support the benefits of astaxanthin supplementation (in the range of 3 to 6 mg/d) on skin health, especially for photoaged skin. [ABSTRACT FROM AUTHOR]

SUMMARY: "Monitoring Sites 1000" – Japan's long‐term monitoring survey was established in 2003, based on the Japanese Government policy for the conservation of biodiversity. Ecological surveys have been conducted on various types of ecosystems at approximately 1000 sites in Japan for 15 years now and are planned to be carried out for 100 years. Since 2008, seaweed communities had been monitored at six sites, featuring the kelp (e.g. Saccharina and Ecklonia; Laminariales) and Sargassum (Fucales) communities in the subarctic and temperate regions of Japan. Annual surveys were carried out during the season when these canopy‐forming seaweeds are most abundant. A non‐destructive quadrat sampling method, with permanent quadrats placed along transects perpendicular to the shoreline, was used to determine species composition, coverage, and vertical distribution of seaweeds at these sites; while destructive sampling was done every 5 years to determine biomass. The occurrence of canopy‐forming species Saccharina japonica (var. japonica) and Ecklonia cava have appeared to be stable at the Muroran (southwestern part of Hokkaido Island) and Shimoda (Pacific coast of middle Honshu Island) sites, respectively; whereas the coverage of Ecklonia radicosa (= Eckloniopsis radicosa) at the Satsuma‐Nagashima site in southern part of Kyushu Island was highly variable until its sudden disappearance from the habitat in 2016. Thalli of E. radicosa lost most of their blades through browsing by herbivorous fish, and thus, this may be one of the causes of the decline. A shift in the community structure related to environmental changes had also been observed at some other sites. Pre‐ and post‐disaster data revealed the impact of the 2011 earthquake and tsunami disasters, including a shift in the vertical distribution of Ecklonia bicyclis (= Eisenia bicyclis) to shallower depths at the Shizugawa site in the Pacific coast of northern Honshu Island, due to seafloor subsidence. [ABSTRACT FROM AUTHOR]

Sea ice algae, comprised mainly of diatoms, are the main primary producers in polar ecosystems, and they are generally distributed with the highest biomass at the bottom of ice. The taxonomy of ice algae has been traditionally investigated using light microscopy, but molecular techniques, including pigment analysis, have recently provided new insights into the diversity and physiology of ice algae. However, no comparative taxonomic survey has been conducted for ice algae thus far. Here, we investigated differences and similarities in (1) the diversity and (2) the photosynthetic strategies of diatom communities in sea ice and the underlying seawater of Saroma-Ko Lagoon, Hokkaido, Japan, using algal pigment signatures determined by ultra-high performance liquid chromatography, light and scanning electron microscopy and Ion Torrent next-generation sequencing techniques targeting the 18S rRNA gene (i.e., DNA barcoding). Ice algae typically possessed greater biomass (> 20-fold) and chlorophyll (Chl) a breakdown products than under-ice phytoplankton, suggesting that the ice algae formed blooms, and cell senescence and disruption could be significant mitigating factors. At the genus level, the diversity of diatoms in sea ice was higher than in under-ice seawater, although the evenness was comparable or lower in ice algae than in under-ice phytoplankton. Ice algae had a larger xanthophyll pool size and a higher ratio of photoprotective to photosynthetic pigments (11-fold and 4.5-fold higher, respectively) than under-ice phytoplankton. The results indicated that ice algae were well adapted to changes in the light regime, which could partly support their survival capability and high taxonomic diversity. [ABSTRACT FROM AUTHOR]

Objectives: To identify the dietary patterns among community-dwelling Japanese older adults and to explore the association between these patterns and sarcopenia. Design: Cross-sectional study. Setting: Kashiwa city, Chiba prefecture, Japan. Participants: Community-dwelling older adults (n = 1241) aged 65 years and over who were not eligible for long-term care. Measurements: Dietary intake was assessed using the brief self-administered diet history questionnaire (BDHQ). Dietary patterns were identified using both principal component analysis and the score on the Japanese diet comprising soybeans and soybean products, fish, vegetables, pickles, mushroom, seaweeds, and fruits. Sarcopenia was defined by the Asian Working Group for Sarcopenia (AWGS) criteria. A binary logistic regression analysis was performed with sarcopenia status as the dependent variable after adjusting for economic status, living alone status, BMI, energy intake, multimorbidity, and physical activity. Results: Participants' mean age was 74.6 years, and 52.1% were male. According to AWGS criteria, 5.1% had sarcopenia. Three dietary patterns were identified from the principal component analysis. Dietary pattern 1 (DP1), showed high loadings for fish, tofu, vegetables, and fruits which are similar to the side dishes in a typical Japanese diet. Dietary pattern 2 (DP2) had high factor loadings for fish, rice, and miso soup which are main dishes in a typical Japanese diet. Dietary pattern 3 (DP3) had a high factor loading for noodles. Men with the lowest tertile of DP1 score had a higher likelihood of being sarcopenic (Adjusted odds ratio (AOR) 3.67, 95% confidence interval (CI) 1.20∓11.2). Women with the lowest tertile of DP2 score had a moderate likelihood of being sarcopenic (AOR 2.71, 95%CI 0.99∓7.46). Low adherence to Japanese dietary pattern was associated with prevalence of sarcopenia in both genders. Conclusion: Adherence to a dietary pattern high in foods characteristic of a Japanese diet including fish, soybean products, vegetables, and fruits was associated with low prevalence of sarcopenia in both genders. [ABSTRACT FROM AUTHOR]

SUMMARY: The effects of irradiance, temperature, thermal‐ and chilling‐light sensitivities on the photosynthesis of a temperate alga, Sargassum macrocarpum (Fucales) were determined by a pulse amplitude modulation (PAM)‐chlorophyll fluorometer and dissolved oxygen sensors. Oxygenic photosynthesis–irradiance curves at 8, 20, and 28°C revealed that the maximum net photosynthetic rates (NPmax) and saturation irradiance were highest at 28°C, and lowest at 8°C. Gross photosynthesis and dark respiration determined over a range of temperatures (8–36°C) at 300 μmol photons m−2 s−1 revealed that the maximum gross photosynthetic rate (GPmax) occurred at 27.8°C, which is consistent with the highest seawater temperature in the southern distributional limit of this species in Japan. Additionally, the maximum quantum yields of photosystem II (Fv/Fm) during the 72‐h temperature exposures were stable at 8–28°C, but suddenly dropped to zero at higher temperatures, indicative of PSII deactivation. Continuous exposure (12 h) to irradiance of 200 (low) and 1000 (high) μmol photons m−2 s−1 at 8, 20, and 28°C revealed greater declines in their effective quantum yields (ΦPSII) under high irradiance. While ΦPSII under low irradiance were very similar with the initial Fv/Fm under 20 and 28°C, values rapidly decreased with exposure duration at 8°C. At this temperature, Fv/Fm did not recover to initial values even after 12 h of dark acclimation. Final Fv/Fm of alga at 28°C under high irradiance treatment also did not recover, suggesting its sensitivity to photoinhibition at both low and high temperatures. These photosynthetic characteristics reflect both the adaptation of the species to the general environmental conditions, and its ability to acclimate to seasonal changes in seawater temperature within their geographical range of distribution. [ABSTRACT FROM AUTHOR]

Background The minerals, vitamins, soluble dietary fibers, and flavonoids of seaweed are protective for preventing cardiovascular diseases. However, the association between seaweed intake and risk of cardiovascular disease has not been established. Objectives We examined the dietary intake of seaweed and its impact upon stroke and ischemic heart disease risk among a Japanese study population. Methods We surveyed 40,707 men and 45,406 women from 2 large cohorts (age range: 40–69 y). Seaweed intake was determined by FFQ at baseline (1990–1994). Incidences of stroke and ischemic heart disease were ascertained until the end of 2009 (Cohort I) or 2012 (Cohort II). Sex-specific cardiovascular disease HRs (95% CIs) were estimated using Cox proportional hazard models after stratification by area and adjustment for cardiovascular disease risk and dietary factors. Results During 1,493,232 person-years of follow-up, 4777 strokes (2863 ischemic stroke, 1361 intraparenchymal hemorrhages, and 531 subarachnoid hemorrhages) and 1204 ischemic heart disease cases were identified. Among men, significant multivariable HRs (95% CIs) for almost daily consumption compared with almost no consumption of seaweed were seen in ischemic heart disease [0.76 (0.58, 0.99); P -trend = 0.04] and total cardiovascular diseases [0.88 (0.78, 1.00); P -trend = 0.08]. Among women, such inverse associations were 0.56 (0.36, 0.85; P -trend = 0.006) for ischemic heart disease and 0.89 (0.76, 1.05; P -trend = 0.10) for total cardiovascular diseases. No significant associations were observed between seaweed intake and risk of total stroke or stroke types among either men or women. Conclusions Seaweed intake was inversely associated with risk of ischemic heart disease. [ABSTRACT FROM AUTHOR]

SUMMARY Trade‐offs are considered key to understanding mechanisms supporting the coexistence of multiple plant species. Thus, understanding the mechanisms underlying trade‐offs is expected to contribute to conservation and management of macroalgal beds composed of diverse macroalgae of rocky shore ecosystems. To test the occurrence of trade‐offs between productivity and thallus toughness as well as pair‐wise thallus trait relationships that are expected to indirectly relate to any trade‐offs, traits and relationships for 13 species of macroalgae from the central area along the Japan Sea coast of Honshu, Japan were examined. In each species we examined for photosynthetic capacity per unit biomass (as Amass) and nitrogen (i.e., photosynthetic nitrogen‐use efficiency, PNUE), nitrogen content (as Nmass), thallus mass per unit thallus area (as TMA) and force required to penetrate the thallus (as Fp, a common index of leaf toughness in land plants by punch test). A significant negative correlation indicating a trade‐off between productivity and thallus toughness was found between Amass or PNUE and Fp. Pair‐wise relationships that were expected to indirectly relate to the trade‐off were as follows. Amass was positively correlated with Nmass. Thalli with high Nmass extensively utilizing nitrogen in the photosynthetic parts, and consequently exhibiting elevated metabolic rates. Moreover, thalli with high Nmass tended to be associated with low TMA, and Nmass decreased with increasing TMA. A significant negative correlation was observed between TMA and Amass or PNUE because of the linkage of high Amass or PNUE with high Nmass and high Nmass associated with low TMA, while a significant positive correlation was observed between TMA and Fp. The two correlations indicate a physiological and structural trade‐off, which underlies the interdependency of thallus traits. Results of multivariate analyses also indicated that the thallus traits interdependently vary across a single axis based on the trade‐off. [ABSTRACT FROM AUTHOR]

Volvox rousseletii is a dioecious species belonging to Volvox sect. Volvox that has previously only been found in Africa. During field surveys in a large dam lake (Lake Sagami) in Kanagawa Prefecture, central Japan, we encountered a Volvox sect. Volvox species that produces dioecious sexual spheroids in the water column. Although sexual induction of this species in culture did not produce adequately well-developed sexual spheroids for species identification, molecular data directly obtained from field-collected sexual spheroids verified the identity of field-collected male and female sexual spheroids as well as cultured materials. Based on molecular and morphological data, the species was identified as V. rousseletii. This is the first record of a dioecious species of Volvox sect. Volvox in Japan. [ABSTRACT FROM AUTHOR]

Objectives: We created a Traditional Japanese Diet Score (TJDS), and to clarify the relationship between TJDS and obesity, ischemic heart disease (IHD), and healthy life expectancy (HALE). Design: Ecological study Setting: Food (g/day/capita) and energy (kcal/day/capita) supply was determined using the Food and Agriculture Organization of the United Nations Statistics Division database. The sum of characteristic traditional Japanese foods (beneficial food components in the Japanese diet: rice, fish, soybeans, vegetables, eggs, and seaweeds; food components rarely used in the Japanese diet: wheat, milk, and red meat) was divided as tertiles (beneficial food components: −1, 0, 1; rarely used food components: 1, 0, −1). Obesity rate was determined using the World Health Organization database. Incidence of IHD, HALE and smoking rate were determined using the Global Burden of Diseases, Injuries, and Risk Factors Study 2015 database. Gross domestic product per capita, percentage of population > 65 years old, and health expenditure were determined using the World Bank database. Education years were obtained from the United Nations Educational, Scientific and Cultural Organization Institute for Statistics. Associations between TJDS and obesity, IHD and HALE were examined in 132 countries with a population of 1 million or greater using a general linear model controlled for co-variables. Results: TJDS was distributed from −6 to 7. TJDS was inversely correlated to obesity (β±SE; −0.70±0.19, p<0.001), IHD (−19.4±4.3, p<0.001), and positively correlated to HALE (0.40±0.14, p<0.01). Conclusions: TJDS is a good indicator of a healthy diet, and applies to preventing obesity, IHD and extending HALE. [ABSTRACT FROM AUTHOR]

Effects of photosynthetically active radiation (PAR) and temperature on the photosynthesis of a subarctic edible brown alga, Saccharina angustata (Laminariaceae, Laminariales), from Hokkaido, Japan, were determined using a pulse amplitude modulation (PAM)–chlorophyll fluorometer and optical dissolved oxygen sensors. Photosynthesis–PAR experiments at 8, 16, and 20 °C revealed highest net photosynthetic rates at 16 °C; whereas, the temperature effect on maximum quantum yield (Fv/Fm) showed the highest Fv/Fm at 7.0 to 8.4 °C. These temperatures corresponded to the optimum temperatures for growth of Japanese Saccharina species. The maximum gross photosynthetic rate from gross photosynthesis–temperature curve was at 21.2 °C. Though consistent with the highest seawater temperature in the study site, it is close to the limit for thermal inhibition, because Fv/Fm above 20 °C was compromised after 48–72 h of incubation. Continuous 6-h exposures to PAR of 200 µmol (low) and 1000 µmol (high) photons m−2 s−1 at 8, 16, and 20 °C caused chronic photoinhibition in the alga, with greater declines in effective quantum yields of photosystem II (ΦPSII) and failure of recovery in post-dark acclimation Fv/Fm under high PAR. This physiological performance provides a basis for understanding the persistence of S. angustata near its southern boundary in the western Pacific. [ABSTRACT FROM AUTHOR]

Abstract Five polyketides, paralactonic acids A-E (1 – 5) were isolated from Paraconiothyrium sp. SW-B-1, an endophytic fungus isolated from the seaweed, Chondrus ocellatus Holmes. Their structures were determined by various spectroscopic methods, predominantly by 2D NMR spectroscopic analyses. The absolute configurations of compounds 1 – 5 were determined by comparison of the experimental and calculated ECD spectra. Compound 5 showed moderate antibacterial activity and restored the growth of a mutant yeast strain inhibited by hyperactivated Ca2+-signaling. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

The article discusses pieces of Japanese debris have begun landing on the west coast of North America from central Alaska to Monterey Bay in California after the Tohoku earthquake and tsunami has ravaged Japan on March 11, 2011. It mentions that researchers have identified several species of algae and cyanobacteria that made it to the U.S. Pacific Northwest coast on floating debris,.

Arsenolipid concentrations were measured in 17 food composites prepared from 152 food items purchased in Shizuoka city, Japan, to (1) determine the food contributing to daily intake of arsenolipids, and (2) estimate the daily intake of arsenolipids. Analysis of arsenolipids was performed by high performance liquid chromatography-inductively coupled plasma mass spectrometry/electrospray ionization tandem mass spectrometry (HPLC-ICP-MS/ESI-MS-MS). Arsenic containing hydrocarbons (AsHCs), arsenic containing fatty acids (AsFAs), and arsenosugar phospholipids (AsSugPLs) were detected only in “algae” and “fish and shellfish” of the 17 food composites in a concentration range of 4.4–233 ng As/g fresh weight (fw). Two cytotoxic arsenolipids, AsHC332 and AsHC360, were detected in “algae” and “fish and shellfish” in the concentrations range of 33–40 ng As/g fw. The estimated average daily intake of AsHC332 and AsHC360 was ca 3000 and 360 ng As/person/day, or 50 and 6.0 ng As/kg bw/day, respectively. The present study indicated that arsenolipids from “algae” and “fish and shellfish” consumption contributed to the daily intake of toxic AsHCs, though the margin of exposure for the AsHC332 and AsHC360 does not appear to pose a health risk for the general Japanese population. [ABSTRACT FROM AUTHOR]

Coastal fisheries are in decline worldwide, and aquaculture has become an increasingly popular way to meet seafood demand. While finfish aquaculture can have substantial adverse effects on coastal ecosystems due mostly to necessary feed inputs, bivalves graze on natural phytoplankton and are often considered for their positive ecosystem services. We conducted two independent studies to investigate the effects of long-line Crassostrea gigas oyster aquaculture on Zostera marina seagrass beds and associated epibiont communities in Akkeshi-ko estuary, Japan. Results from both studies yielded no evidence of an effect of oyster aquaculture on the morphology, density, or biomass of Z. marina, but significant differences were apparent in the epibiont community. Reference seagrass beds located away from aquaculture had higher seagrass epiphyte loads and higher abundances of amphipods. Conversely, seagrass beds below aquaculture lines had higher sessile polychaete biomass and higher isopod abundances. Our results suggest that the presence of oyster aquaculture may have indirect effects on seagrass by changing epibiont community composition and relative abundances of species. One proposed mechanism is that cultured oysters feed on epiphytic diatoms and epiphyte propagules before they can settle on the seagrass, which reduces epiphyte loads and influences subsequent faunal settlement. If carefully implemented and monitored, long-line oyster aquaculture may be a sustainable option to consider as bivalve aquaculture expands to meet global seafood demand, but further work is needed to fully assess and generalize the community-level effects on seagrass epibionts. [ABSTRACT FROM AUTHOR]

Little is known about the dietary patterns of Asian populations aged >=85 years and their associated factors. Thus, we aimed to (1) identify these dietary patterns and (2) clarify the relationships between the dietary pattern and health outcomes in a community-dwelling very old population. The Tokyo Oldest Old Survey on Total Health study is an observational cohort study comprising 512 Japanese subjects (women, n=288; men, n=224; age, 87.8±2.2 years). Dietary patterns were assessed by principal component analysis using a brief self-administered diet history questionnaire. Barthel index, Mini-Mental State Examination, and oral health status [maximum occlusal force (MOF), denture use, and dentulous / edentulous state] were also measured. Two dietary patterns were identified. The first factor component "traditional Japanese" was characterized by a high consumption of vegetables, seaweed, legumes, and fish. The second factor component "noodles and confectioneries" was characterized by a high consumption of noodles, confectioneries, and non-alcoholic beverages. Multivariable analysis showed that the "traditional Japanese" dietary pattern was inversely associated with dentulous state (OR: 0.53; 95% CI: 0.34-0.82), the lowest tertile of MOF (OR: 0.64; 95% CI: 0.42-0.99), and denture use (OR: 2.42; 95% CI: 1.26- 4.63) even after adjustment for potential confounders. Furthermore, the "noodles and confectioneries" dietary pattern was inversely associated with the lowest tertile of MOF (OR: 0.62; 95% CI: 0.40-0.94). However, there were no significant associations between these dietary patterns and disability or cognitive function. We identified two dietary patterns in the very old population, which were associated with oral health status. [ABSTRACT FROM AUTHOR]

Many food products are recommended to give health benefits. Thus algae superfoods consumption is growing worldwide, although quite a few studies have examined the quantities of radionuclides they contain and their potential effects on human health. The study presents radioactive 40K, 137Cs, 226Ra, 228Ra, and 234Th in algae supplements available worldwide for human consumption. Samples have been quantified by gamma-ray spectrometry and the activity concentrations (Bq/kg dw) ranged 0.23–0.65 (137Cs) followed by 1.76–10.7 (226Ra), 0.20–12.7 (228Ra), 11.6–24.2 (234Th), and 20.1–400 (40K). Also, the effective radiation doses from 40K, 137Cs, 226Ra, 228Ra, and 234Th decay ingested with analyzed algae supplements have been estimated. The highest annual effective dose reaching 15.1 µSv/year has been assessed for naturally occurring 226Ra in Chlorella vulgaris from Japan. The Fukushima Nuclear Power Plant has not significantly impacted the effective dose from 137Cs present in algal superfoods. Based on the study, the activity concentrations of radionuclides seem to be low, the naturally occurring radionuclides would give the highest effective doses, and the investigated algae supplements could be considered safe food. • 40K, 137Cs, 226Ra, 228Ra, 234Th are present in algae supplements. • The analyzed algae supplements were not contaminated with nuclear fission product 137Cs. • The highest annual effective dose could come from the naturally occurring 226Ra. • Algal superfoods can be considered safe. [ABSTRACT FROM AUTHOR]

Recent phylogenetic studies of the genus Pterosiphonia suggest that Pterosiphonia dendroidea and Pterosiphonia tanakae are conspecific and show its wide geographic distribution in the Pacific. Pterosiphonia dendroidea was originally described as Polysiphonia dendroidea from Peru and later transferred to Pterosiphonia. Pterosiphonia dendroidea was characterized by diagnostic features such as its light cortication, the presence of trichoblasts, 8-12 pericentral cells, branches with the production of 3- to 5-order laterals, and congenital fusion of 2-3 segments. Pterosiphonia tanakae shares these features. Our phylogenetic analysis using rbcL sequences reveals a low gene sequence divergence (0.5%-0.7%) between the samples of P. dendroidea and P. tanakae. We propose that P. tanakae is a later synonym of P. dendroidea, and our study indicates the wide distribution of P. dendroidea in the northern and the southern Pacific Ocean. [ABSTRACT FROM AUTHOR]

Short-term growth dynamics of diatoms were examined by daily sampling and microcosm experiments under in situ environmental conditions in the late rainy season (July) for 10 days and by weekly sampling during summer (June-September) at a fixed point in the Yatsushiro Sea, Japan. During the daily sampling period, a bloom of diatoms such as Skeletonema spp., Thalassiosira spp., and Chaetoceros spp. (>10 cells mL) occurred in the surface and subsurface layers during the first half of the period, but the population of diatoms declined and sank to the bottom by an average of about 1 m day during the second half of the observation period. Daily changes in net growth rates of the three dominant diatom genera (ranging from −3.8 to 3.0 day), which were estimated by daily 24-h microcosm incubations, roughly corresponded with those in ambient cell densities in the surface layer. The relationship between net growth rates and environmental factors suggest that the growth dynamics of diatoms were regulated by irradiance and river discharge (i.e., salinity and phosphate concentration) during the observation period. The field observations using daily microcosm experiments revealed that the maintenance and decline of a diatom bloom on a daily/weekly time scale are controlled by the rapid growth and sinking responses of diatoms following abrupt changes in coastal environments in the Yatsushiro Sea. [ABSTRACT FROM AUTHOR]

Background: While some dietary patterns are associated with the incidence of type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD), the relationship between dietary pattern and risk factors for CVD in patients with T2DM remains to be clarified. The aim of this study was to identify dietary patterns and investigate the relationship between dietary patterns and potential risk factors for CVD in patients with T2DM.Methods: The study participants comprised 726 Japanese T2DM outpatients free of history of CVD. Life styles were analyzed using self-reported questionnaires. The relationship between dietary patterns, identified by factor analysis, and potential risk factors for CVD was investigated by linear and logistic regression analyses.Results: Six dietary patterns were identified by factor analysis. Especially, three dietary patterns were associated with risk factors for CVD. The "Seaweeds, Vegetables, Soy products and Mushrooms" pattern, characterized by high consumption of seaweeds, soy products and mushrooms, was associated with lower use of diabetes medication and healthier lifestyles. The "Noodle and Soup" pattern, characterized by high consumption of noodle and soup was associated with higher body mass index, alanine aminotransferase, aspartate aminotransferase, γ-glutamyl transpeptidase and triglyceride levels. The "Fruit, Dairy products and Sweets" pattern was associated with lower γ-glutamyl transpeptidase levels, blood pressure, albuminuria and brachial-ankle pulse wave velocity.Conclusions: The findings suggested that dietary patterns correlated with risk factors for CVD in T2DM patients. [ABSTRACT FROM AUTHOR]

Application of herbicides to paddy fields in Japan has strong seasonality, and their environmental concentrations exhibit clear spatiotemporal variation. The authors developed an approach that combines a multimedia environmental exposure model (Grid- Catchment Integrated Modeling System) and density dynamics models for algae. This approach enabled assessment of ecological risk when the exposure concentration shows spatiotemporal variation. First, risk maps of 5 herbicides (pretilachlor, butachlor, simetryn, mefenacet, and esprocarb) were created from the spatial predictions of environmental concentrations and 50% inhibitory concentrations of the herbicides. Simulations of algal density dynamics at high-risk sites were then conducted by incorporating the predicted temporal dynamics of the environmental concentration of each herbicide at the sites. The results suggested that the risk of pretilachlor was clearly the highest of the 5 herbicides, in terms of both the spatial distributions and the temporal durations. The present study highlights the importance of integrating exposure models and effect models to clarify spatial and temporal risk and to develop management plans for chemical exposure that shows high spatiotemporal variation. [ABSTRACT FROM AUTHOR]

This study on the origin of particulate organic matter (POM) in a river under efficient water use for irrigation in a basin was carried out on the Shin River in Kagawa Prefecture, Japan. The organic pollution in the basin where water resources are scarce was studied. The level of POM in the Shin River was significantly influenced by the natural and artificial hydrological environment in the river basin. The degree of organic pollution in the Shin River was high, and most of the organic matter was algae. The δO of water of the middle and lower reaches of the Shin River was high, and water subjected to evaporation for a lengthy time period in the basin flows into the river. The concentration of organic matter in the Shin increases along with the increase in δO. Algae also increases in the stay waters in the basin of the middle-lower reaches and flows into the Shin. It was thought that the irrigation ponds in the basin were the main sources of water and organic matter for the river. This tendency was notable during the nonirrigation season in that the volume of water in the basin decreased. On the other hand, the proportion of algae in organic matter in the river decreased when there was considerable precipitation. [ABSTRACT FROM AUTHOR]

Tiger shrimp is one of the major candidate species for export oriented aquaculture which dominates the seafood market in regions of European Union, Japan and USA. Carotenoid content in seafood has now become one of the important criteria in determining the quality of edible product. Recent trends in supplementing fish diets with natural pigment source are an alternative to the utilization of expensive synthetic pigments. In this context, green algae Enteromorpha intestinalis was selected as a source of natural pigment for inclusion in the diet of tiger shrimp Penaeus monodon. Astaxanthin being an important category of carotenoid pigment was monitored in shrimp muscle tissue during the feeding trial. Significant variation (p<0.05) was observed between the experimental groups as confirmed through ANOVA thus exhibiting higher astaxanthin content of shrimps (18.70 ± 4.48 ppm) fed with E. intestinalis incorporated diet as compared to control (15.80 ± 2.33 ppm). The present programme therefore emphasizes on the quality improvement of aquaculture product by dietary inclusion of algae as a natural pigment source. [ABSTRACT FROM AUTHOR]

The effect of irradiance and temperature on the photosynthesis of the red alga, Pyropia tenera, was determined for maricultured gametophytes and sporophytes collected from a region that is known as one of the southern limits of its distribution in Japan. Macroscopic gametophytes were examined using both pulse-amplitude modulated fluorometry and/or dissolved oxygen sensors. A model of the net photosynthesis-irradiance ( P-E) relationship of the gametophytes at 12°C revealed that the net photosynthetic rate quickly increased at irradiances below the estimated saturation irradiance of 46 μmol photons m−2 s−1, and the compensation irradiance was 9 μmol photons m−2 s−1. Gross photosynthesis and dark respiration for the gametophytes were also determined over a range of temperatures (8-34°C), revealing that the gross photosynthetic rates of 46.3 μmol O2 mgchl-a−1 min−1 was highest at 9.3 (95% Bayesian credible interval ( BCI): 2.3-14.5)°C, and the dark respiration rate increased at a rate of 0.93 μmol O2 mgchl-a−1 min−1°C−1. The measured dark respiration rates ranged from −0.06 μmol O2 mgchl-a−1 min−1 at 6°C to −25.2 μmol O2 mgchl-a−1 min−1 at 34°C. The highest value of the maximum quantum yield ( Fv/ Fm) for the gametophytes occurred at 22.4 ( BCI: 21.5-23.3) °C and was 0.48 ( BCI: 0.475-0.486), although those of the sporophyte occurred at 12.9 ( BCI: 7.4-15.1) °C and was 0.52 ( BCI: 0.506-0.544). This species may be considered well-adapted to the current range of seawater temperatures in this region. However, since the gametophytes have such a low temperature requirement, they are most likely close to their tolerable temperatures in the natural environment. [ABSTRACT FROM AUTHOR]

The Fukushima Daiichi Nuclear Power Plant accident emitted radioactive substances into the environment, contaminating a diverse range of organisms. Stream algae, litter, sand substrate, aquatic insects and fishes are among the organisms that have been impacted. Radioactive Cs contaminations in the litter and sand substrate were elevated where the atmospheric dose rate in the air was high. Radioactive Cs contaminations in algae and aquatic insects varied irregularly; nevertheless, radioactive Cs contaminations in aquatic insects in pools were consistently higher than those in stream riffles. Contamination by the radioactive Cs differed by species, location and stream velocity. This study was undertaken in a limited number of samples and sites, with more extensive studies planned to fully determine the impact of radionuclides on aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Aim This study aimed to determine whether mechanical cervical dilatation with a laminaria tent in women with premature rupture of membranes (PROM) at term may influence the maternal/neonatal outcomes. Methods We reviewed the medical records and histopathologic results of the placenta in 782 women with PROM at term. Of the 486 women seen prior to 2010 (group 1), 85 had Bishop scores of 5 or less and underwent insertion of laminaria tents (group A). In the 296 women admitted after 2010 (group 2), 27 had Bishop scores of 5 or less and underwent labor management without insertion of laminaria tents (group B). The patient characteristics, delivery course and neonatal outcomes were compared between the groups. Results There were no significant differences in the maternal age, percentage of nulliparas, body mass index, gestational age at delivery or Bishop score between the groups. The Bishop score improved from 2.5 to 6.1 after laminaria tent insertion in group A. However, there were no significant intergroup differences in the frequency of use of labor-inducing agents or the time interval from PROM to delivery. The incidence of clinical/pathological chorioamnionitis was not higher in group A than in group B. No significant differences were found in the Apgar scores, umbilical artery p H or frequency of asphyxia neonatorum between the groups. Mechanical cervical dilatation by laminaria tent insertion neither increased the incidence of infection nor contributed to improvement of the perinatal prognosis. Conclusion Mechanical cervical dilatation does not provide any benefit for women with PROM at term. [ABSTRACT FROM AUTHOR]

A self-control, randomized, and open-label clinical trial was performed to test the effects of the unicellular green algae Chlorella and hot water extract supplementation on quality of life (QOL) in patients with breast cancer. Forty-five female patients with breast cancer who were living at home and not hospitalized were randomly assigned to 3 groups receiving vitamin mix tablet (control), Chlorella granules (test food-1), or Chlorella extract drink (test food-2) daily for one month. The Functional Assessment of Cancer Therapy-Breast (FACT-B), the Izumo scale for abdominal symptom-specific QOL, and a narrative-form questionnaire were used to determine outcomes. Data of thirty-six subjects were included for final analysis. FACT-B scores at presupplementation found no significant group differences in all subscales. Scores on the breast cancer subscale in the Chlorella granule group significantly increased during the supplementation period (P = 0.042). Fifty percent of the Chlorella extract group reported positive effects by the test food such as reduction of fatigue and improvements of dry skin (P < 0.01 versus control group). The findings suggested the beneficial effects of Chlorella on breast cancer-related QOL and of Chlorella extract on vitality status in breast cancer patients. These findings need to be confirmed in a larger study. [ABSTRACT FROM AUTHOR]

Background: To. our knowledge, there are no previous reports that assessed the association between dietary patterns and risk of dementia in Asian populations. Objective: We investigated dietary patterns and their potential association with risk of incident dementia- in a general Japanese population. Design: A total of 1006 community-dwelling Japanese subjects without dementia, aged 60-79 y, were followed up for a median of 15 y. The reduced rank regression procedure was used to efficiently determine their dietary patterns. Estimated risk conferred by a particular dietary pattern on the development of dementia was computed by using a Cox proportional hazards model. Results: Seven dietary patterns were extracted; of these, dietary pattern I was correlated with high, intakes of soybeans and soybean products, vegetables, algae,, and milk and dairy products and a low intake of rice. During the follow-up, 271 subjects developed all-cause, dementia. Of these individuals, 144 subjects had Alzheimer disease (AD), and' 88 subjects had vascular dementia (VaD). After adjustment for potential confounders, risks of development of all-cause dementia, AD, and VaD. were reduced by 0.66 (95% CI: 0.46, 0.95), 0.65 (95% CI: 0:40, 1.06), and 0:45 (95% CI: 0.22, 0,91), respectively, in subjects in the highest quartile of score for dietary pattern. 1. compared with, subjects, in the lowest quartile. Conclusion:. Our findings suggest that a higher adherence to a dietary pattern characterized by a high intake of soybeans and soybean products, vegetables, algae, and milk and dairy products and a low intake of rice is associated with reduced risk of dementia in the general Japanese population. [ABSTRACT FROM AUTHOR]

Monitoring of harmful algal bloom (HAB) species in coastal waters is important for assessment of environmental impacts associated with HABs. Co-occurrence of multiple cryptic species such as toxic dinoflagellate Ostreopsis species make reliable microscopic identification difficult, so the employment of molecular tools is often necessary. Here we developed new qPCR method by which cells of cryptic species can be enumerated based on actual gene number of target species. The qPCR assay targets the LSU rDNA of Ostreopsis spp. from Japan. First, we constructed standard curves with a linearized plasmid containing the target rDNA. We then determined the number of rDNA copies per cell of target species from a single cell isolated from environmental samples using the qPCR assay. Differences in the DNA recovery efficiency was calculated by adding exogenous plasmid to a portion of the sample lysate before and after DNA extraction followed by qPCR. Then, the number of cells of each species was calculated by division of the total number of rDNA copies of each species in the samples by the number of rDNA copies per cell. To test our procedure, we determined the total number of rDNA copies using environmental samples containing no target cells but spiked with cultured cells of several species of Ostreopsis. The numbers estimated by the qPCR method closely approximated total numbers of cells added. Finally, the numbers of cells of target species in environmental samples containing cryptic species were enumerated by the qPCR method and the total numbers also closely approximated the microscopy cell counts. We developed a qPCR method that provides accurate enumeration of each cryptic species in environments. This method is expected to be a powerful tool for monitoring the various HAB species that occur as cryptic species in coastal waters. [ABSTRACT FROM AUTHOR]

Abstract: In this study, an upper limit in the solar energy conversion efficiency which can be translated to a maximum potential algal yield of a large-scale culture is calculated based on the algal productivity model in which light and nutrient are made the growth rate limiting factors, and taking the design characteristics of the cultivation system into account. Our results indicate that for the production of low-cost biodiesel within the limits of the wastewater quality standards, that the culturing of high lipid content algae within a raceway pond would provide an appropriate solution for manufacturing biodiesel from algae. However, due to inefficient sunlight utilization and due to the large amount of fertilizer required in raceway ponds, a greater effluent recycle rate would have to be implemented to reduce the amount of fertilizer discharge to meet the wastewater quality standards and to maximize the attainable productivity of algal biomass. [Copyright &y& Elsevier]

Calcified sponges, algae, and reef problematica are abundant yet poorly known from the Triassic of Japan. They are abundant in shallow-water carbonate, redeposited blocks of the Sambosan Accretionary Complex, Konosé Group, and southern Kyushu. Based on study of thin-sections from reef limestone exposed along the Kuma River, some important organisms and reef microfacies are described, which seem typical of Upper Triassic reef complexes. The most abundant reef organisms are hypercalcified sponges, including sphinctozoans, inozoans and chaetetids, followed by cyanophycean algae (including ' Tubiphytes'-like organisms), and solenoporacean red algae. Loose sponge spicules in one thin-section also indicate the occurrence of rare hexactinellid sponges. Chambered demosponges described from the Konosé carbonate rocks include Solenolmia manon manon (Münster), Colospongia sp., Jablonskyia andrusovi (Jablonský), several unidentified chambered sponges as well as the inozoid Permocorynella sp. 1 and Permocorynella sp. 2. Also present are chaetetid sponges and solenoporacean red algae belonging to Parachaetetes cassianus (Flügel) and Parachaetetes? sp. or Solenopora? sp. Especially abundant in thin-sections are cyanophyceans and ' Tubiphytes'-like organisms. Among the organisms is Cladogirvanella Ott and Hedstroemia sp. The composition of the biota and presence of typical problematic organisms increases our knowledge of shallow-water Upper Triassic carbonate rocks in a remote setting in western Panthalassa. The composition of the biota indicates a mostly Carnian age. Most comparable organisms are known from both the northeastern and southern Tethys. [ABSTRACT FROM AUTHOR]

- Social and foraging modes in fish often vary between individuals with different body sizes and between populations under different ecological conditions. We studied social and foraging behaviour of algae-grazing fish Plecoglossus altivelis ryukyuensis (Ryukyu-ayu) inhabiting Japanese subtropical island streams. Ryukyu-ayu exhibited four behavioural modes: territorial, schooling, solitary and floating. Their body sizes differed among these modes. Territorial fish predominantly foraged on benthic algae, whereas schooling and solitary individuals frequently consumed drifting materials as well. Schooling fish were smaller than territorial fish, but, unlike some other algae-grazing fish species, did not use schooling to gain access to food within territories. Territorial fish attacked smaller conspecifics but exhibited lateral display towards larger fish and schooling fish while occasionally attacking grazing gobies. Larger fish maintained larger feeding territories and occupied territories for longer periods than smaller fish did. This suggests that, in Ryukyu-ayu, intra- and interspecific food competitions and relative body size can influence diverse behavioural modes and duration of territory occupation. We also found that Ryukyu-ayu foraged more often and had larger feeding territories than ayu P. a. altivelis inhabiting temperate streams. We conclude that foraging strategies of Ryukyu-ayu may have adapted to subtropical island streams, where algal productivity is much lower than that in temperate regions. [ABSTRACT FROM AUTHOR]