Evidence against hydrogen-based microbial ecosystems in basalt aquifers

It has been proposed that hydrogen produced from basalt-ground-water interactions may serve as an energy source that supports the existence of microorganisms in the deep subsurface on Earth and possibly on other planets. However, experiments demonstrated that hydrogen is not produced from basalt at an environmentally relevant, alkaline pH. Small amounts of hydrogen were produced at a lower pH in laboratory incubations, but even this hydrogen production was transitory. Furthermore, geochemical considerations suggest that previously reported rates of hydrogen production cannot be sustained over geologically significant time frames. These findings indicate that hydrogen production from basalt-ground-water interactions may not support microbial metabolism in the subsurface.     

Visible quantum cutting in LiGdF4:Eu3+ through downconversion

For mercury-free fluorescent lamps and plasma display panels, alternative luminescent materials are required for the efficient conversion of vacuum ultraviolet radiation to visible light. Quantum cutting involving the emission of two visible photons for each vacuum ultraviolet photon absorbed is demonstrated in Eu3+-doped LiGdF4 with the concept of downconversion. Upon excitation of Gd3+ with a high-energy photon, two visible photons can be emitted by Eu3+ through an efficient two-step energy transfer from Gd3+ to Eu3+, with a quantum efficiency that approaches 200 percent.     

Effects of Putative Growth or Health‐Enhancing Dietary Additives on Juvenile Olive Flounder,Paralichthys olivaceus,Performance

The effect on growth and body composition of various dietary additives with putative growth or health‐enhancing properties were determined in juvenile olive flounder (25 g initial weight). Nine experimental diets were prepared to contain one of the following additives: control (Con) with no additive, Opuntia ficus‐indica ver. saboten (OF), propolis (PP), lactic acid bacteria (LA), γ‐poly‐glutamic acid (PG), onion extract (OE), organic sulfur (OS), Biostone® (BS), and fig extract (FE). Fishmeal, dehulled soybean meal, and corn gluten were used as the protein source of the experimental diets. Wheat flour and soybean oil were used as the carbohydrate and lipid sources, respectively. Dietary additives were included in each experimental diet at 1% at the expense of wheat flour except for the FE (aqueous), which was substituted at 1% of the amount of water added to the diet. Fish were hand‐fed to satiation twice a day for 6 d/wk for 6 wk. Weight gain of fish fed the OE diet was higher than that of fish fed with the PP diet. Chemical composition of fish was not different among the experimental diets. OE was the most effective dietary additive to improve performance of olive flounder among additives used in this study.     

Edwardsiella tarda infection in Korean catfish,Silurus asotus,in a Korean fish farm

Mass mortality of Korean catfish, Silurus asotus, occurred in a culture farm situated in Jeollabukdo Province, Korea. The cumulative mortality rates reached up to 5% of the total fish in the farm per day. In clinical signs, the affected fish showed abdominal distension, vent protrusion, enteritis, liver congestion and abscess‐like lesions in enlarged spleen and kidney. Histopathologically, in the liver, hepatocytes lost fat and underwent atrophy or necrosis. The spleen showed necrotized splenocytes and a haemorrhagic pulp. In the kidney, glomerular destruction, degeneration of renal tubular epithelial cell and haemorrhage were observed. However, necrotic muscular lesions were not observed. A pure bacterial isolate was obtained from the liver, spleen and kidney lesions of affected fish. Experimental infection of normal catfish with the isolate resulted in the development of clinical signs similar to those seen on the farm. The isolates were identified as Edwardsiella tarda through biochemical tests (99.4%) and analysis of bacterial genes (16S rDNA) sequences (98%). The bacteria possessed two virulent genes: sodB and katB genes. These results suggest that E. tarda can act as a pathogen of farmed catfish. This is the first report showing that E. tarda caused mortality in cultured Korean catfish.     

Effect of fishmeal substitution with various animal and/or plant protein sources in the diet of the abalone Haliotis discus hannai Ino

The effect of dietary substitution of animal and/or plant protein sources for fishmeal on the growth and body composition of juvenile abalone was determined. Nine experimental diets in triplicate were prepared: Con, SM, PM, CM, SPM, MB, SM+CM, SM+SPM and CM+SPM diets. A 350 g kg^?1 fishmeal was included in the Con diet, and the whole fishmeal was substituted with a 580 g kg^?1 soybean meal (SM), 335 g kg^?1 poultry meal (PM), 370 g kg^?1 corn gluten meal (CM), 325 g kg^?1 silkworm pupae meal dehydrated (SPM), 590 g kg^?1 meat and bone meal (MB), the combined 290 g kg^?1 soybean meal and 180 g kg^?1 corn gluten meal (SM+CM), 290 g kg^?1 soybean meal and 160 g kg^?1 silkworm pupae meal dehydrated (SM+SPM) and 180 g kg^?1 corn gluten meal and 170 g kg^?1 silkworm pupae meal dehydrated (CM+SPM) diets respectively. All experimental diets were iso‐nitronic and iso‐lipidic. The survival of abalone fed with the SM and SM+SPM diets was higher than that of abalone fed with the CM, SPM, MB and CM+SPM diets. Weight gain of abalone fed with the SM+SPM diet was higher than that of abalone fed with all the other experimental diets, except for that of abalone fed with the SM+CM diet. The combined soybean meal and corn gluten meal (SM+CM) or silkworm pupae meal (SM+SPM) could be replaced with the whole fishmeal in the diet for abalone and improved its performance.     

Status of giant clam resources around Okinawa‐jima Island,Ryukyu Archipelago,Japan

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Scalarane-Type Sesterterpenoids from the Marine Sponge Lendenfeldia sp. Alleviate Inflammation in Human Neutrophils

Sponge-derived scalaranes are remarkable sesterterpenoids previously found to exhibit profound inhibitory effects against neutrophilic inflammation. In our current work, we constructed the metabolomic profile of marine sponge Lendenfeldia sp. for the first time using a tandem mass spectrometry (MS/MS) molecular networking approach. The results highlighted the rich chemical diversity of these scalaranes, motivating us to conduct further research to discover novel scalaranes targeting neutrophilic inflammation. MS- and NMR-assisted isolation and elucidation led to the discovery of seven new homoscalaranes, lendenfeldaranes K–Q (1–7), characterized by methylation at C-24, together with five known derivatives, lendenfeldarane B (8), 25-nor-24-methyl-12,24-dioxoscalar-16-en-22-oic acid (9), 24-methyl-12,24,25-trioxoscalar-16-en-22-oic acid (10), felixin B (11), and 23-hydroxy-20-methyldeoxoscalarin (12). Scalaranes 1–4 and 6–12 were assayed against superoxide anion generation and elastase release, which represented the neutrophilic inflammatory responses of respiratory burst and degranulation, respectively. The results indicated that 1–3 and 6–12 exhibited potential anti-inflammatory activities (IC₅₀ for superoxide anion scavenging: 0.87~6.57 μM; IC₅₀ for elastase release: 1.12~6.97 μM).     

Purification and characterization of cysteine proteinase inhibitors from crucian carp <Emphasis Type="Italic">Carassius auratus</Emphasis> eggs

Two cystatins (cst-I and cst-II) were purified from crucian carp eggs by acidification and subsequent ion exchange and molecular sieve chromatography. The molecular masses of cst-I and cst-II analyzed by sodium dodecyl sulfate–polyacrylamide gel electrophoresis were 11.9 and 14.4 kDa, respectively, under reducing conditions and 13.5 and 12.7 kDa, respectively, under non-reducing conditions. The cst-I and cst-II molecules were stable after 30 min of incubation at 60 and 50°C, respectively. There was no significant loss in the inhibitory activity of either cst in the pH range 4–11. These two cystatins were able to affect the proteolysis of papain, cathepsin L, and bromelain, but they were unable to inhibit cathepsin B and trypsin. The partial N-terminal amino acid sequences of both cst inhibitors were homologous and that of cst-I was recognized as NH₂-AGIPGGLVDADINDADVQ. This latter fragment shared 88.9% identity to common carp cystatin and 44.4–55.6% to cystatins of other aquatic animals. Based on these results, we conclude that the two cst inhibitors are members of family II cystatin.     

Herbicidal and biological characteristics of a new benzenesulfonylurea compound K-11451 under submerged paddy conditions

The new benzenesulfonylurea K-11451, an α-hydroxy-β-fluoropropyl- compound, applied at 3–9 g ha ⁻¹, controlled annual and perennial weeds grown in submerged paddy soil under greenhouse conditions. It effectively controlled barnyardgrass at growth stages varying from pre-emergence to the five-leaf stage. The compound inhibited acetolactate synthase, I₅₀ values for the enzyme isolated from barnyardgrass and rice being 56 and 67 nM , respectively. K-11451 inhibited the growth of rice when it was transplanted at a shallow depth (0–1 cm) and water leaching from the paddy soil was high (3–5 cm per day). With a water depth of 3 cm, the compound appeared to move readily down into the paddy soil and had the relatively short half-life of 15.2 days under submerged paddy conditions. A mixture of K-11451 + mefenecet + daimuron (9 + 250 + 250 g ha⁻¹) controlled almost all weeds in the paddy field without injury to rice, so that the combination could be used as a ‘one-shot’ herbicide in rice culture.