Reaction wood anatomy and lignin distribution in <Emphasis Type="Italic">Gnetum gnemon</Emphasis> branches

This study investigated the anatomical and chemical characteristics of the reaction wood of a gymnpsperm species, Gnetum gnemon, and discussed on contributing factor for the type of reaction wood in this species. Cell morphology, microfibril angle (MFA) of the S₂ layer and lignin distribution in secondary walls of tracheary elements, and lignin content were examined on three branches. Observations included no G-layer formation, significant decreases in vessel frequency, and altered MFA, and visible-light absorbance after lignin colour reactions in tracheid and fiber tracheid walls on the upper side in almost all samples. These results suggest that reaction wood in G. gnemon was similar to that in ‘tension-wood-like-reaction wood’ in angiosperms. On the other hand, reaction wood showed decrease in the lignin concentration in the fiber tracheid walls compared to the tracheid walls. In addition, the lignin in the tracheid and fiber tracheid walls was originally rich in syringyl units, suggesting that changes in the anatomical and chemical characteristics of secondary xylem due to reaction wood formation might relate to the ratio of the syringyl to guaiacyl units in lignin in the cell walls which function for mechanical support.     

Search for an index for the taste of Japanese Black cattle beef by panel testing and chemical composition analysis

To search for an index for chemical composition related to superior taste in Japanese Black beef, we conducted panel tests and analyzed the chemical composition of seven beef brands. Thirty‐five sirloin beefs from five heifers were used in this study, sold under seven beef brands graded as more than A4 on the Japanese Meat Grade scale. The chemical composition analyses assessed both raw and roasted meat, the latter of which was roasted under the same conditions as those used for the panel test. Results of the panel test and chemical composition analyses revealed that fatty acid composition, sugar content, adenosine triphosphage (ATP)‐related compounds, amino acid composition and odor composition in the sirloin meat differed among beef brands. Furthermore, the correlations of chemical compositions between roasted and raw meat were significantly high. Sugar content and ATP‐related compounds in roasted meat were significantly correlated with the item ‘overall evaluation’ of the panel test. ATP‐related compounds, such as inosinic acid, carnosine and taurine, in roasted and raw meat were correlated significantly with the item ‘umami intensity’ of the panel test. These results suggest that the composition of these components is important for an index related to the overall evaluation of beef.     

Population structure of Nga Myin Yinn Silonia silondia in the Ayeyarwady River,Myanmar, by mitochondrial DNA markers

Fisheries Science - The Silond catfish Silonia silondia, locally known as Nga Myin Yinn, is a commercially important fish in Myanmar; however, fundamental knowledge of its population structure is...     

Primary and secondary structures of grammistins, peptide toxins isolated from the skin secretion of the soapfish Pogonoperca punctata

SUMMARY: Six peptides (grammistins Pp 1, 2a, 2b, 3, 4a and 4b) with both hemolytic and ichthyotoxic activities were isolated from the skin secretion of the soapfish Pogonoperca punctata by gel filtration and reverse-phase high performance liquid chromatography. They were completely sequenced and found to be simple peptides differing from the previous suggestion that they are peculiar peptides with tertiary amine or quaternary ammonium base moieties. Grammistins Pp 1, 2a and 2b were composed of 13 residues, Pp 3 of 25 residues and Pp 4a and 4b of 24 residues. While grammistins Pp 4a and 4b were identical and highly homologous with grammistin Gs 2 previously isolated from another soapfish Grammistes sexlineatus , the other grammistins did not have homologies with any proteinic or peptidic toxins known to date. Judging from circular dichroism data, helical wheel projections and hydrophobic moment plots, all the isolated grammistins are surface-seeking peptides with an abundance in amphiphilic α-helicity, similar to pardaxins from the skin secretion of two species of soles and melittin from bee venom as well as the G. sexlineatus grammistins.     

The Application of Three-Dimensional Internal Structure Microscopy in the Observation of Mare Ovary

The ovary of the mare has a unique structure which differs totally from that of other mammals. However, because of its relatively large size, conventional histological techniques were unsuitable for the observation of the internal structure of the whole ovary. Three-dimensional internal structure microscopy (3D-ISM) consists of a cryotome-CCD camera-laser disc recorder-PC-based control system coupled with a graphic workstation. The internal structure of the ovary is observed by processing over more than 1,000 stored images of serially sliced surfaces of each frozen equine ovary. The 3D reconstruction was done using the full-coloured, volume-rendering method. The relationship between the localization of medulla, cortex and ovulation fossa was clarified. The ovulation fossa is localized in the centre of the ovary and is surrounded by a broad ovarian cortex. A trace of ovulation was observed only at the ovulation fossa. Medulla are localized in narrow peripheral areas. The phenomenon of the competition to occupy the cortical area ahead of the ovulation fossa by developing secondary follicles was visualized. Spatial localization of various sized follicles was identified from 3D-reconstructed images. In this study, it has been clarified that application or this novel computerized technique can clarify the anatomical arrangements of the equine ovary and the complex mechanism of equine follicular development.     

The gut microflora and the uptake of glucose from the small intestine of the chick

1. Chicks whose growth rate had been depressed either by a fully conventional flora or by association with a bile acid deconjugating strain of Streptococcus faecium and/or a filterable agent from chicken droppings showed no significant reduction in uptake of 3‐O‐methyl‐a‐D‐glucopyranose compared with germ‐free birds.

2. Association with a microflora increased the weight of the gut per unit length.     

Breeding of ‘Manten-Kirari’, a non-bitter and trace-rutinosidase variety of Tartary buckwheat (Fagopyrum tataricum Gaertn.)

Here, we developed a new Tartary buckwheat cultivar ‘Manten-Kirari’, whose flour contains only trace amounts of rutinosidase and lacked bitterness. The trace-rutinosidase breeding line ‘f3g-162’ (seed parent), which was obtained from a Nepalese genetic resource, was crossed with ‘Hokkai T8’ (pollen parent), the leading variety in Japan, to improve its agronomic characteristics. The obtained progeny were subjected to performance test. ‘Manten-Kirari’ had no detectable rutinosidase isozymes in an in-gel detection assay and only 1/266 of the rutinosidase activity of ‘Hokkai T8’. Dough prepared from ‘Manten-Kirari’ flour contained almost no hydrolyzed rutin, even 6 h after the addition of water, whereas the rutin in ‘Hokkai T8’ dough was completely hydrolyzed within 10 min. In a sensory evaluation of the flour from the two varieties, nearly all panelists detected strong bitterness in ‘Hokkai T8’, whereas no panelists reported bitterness in ‘Manten-Kirari’. This is the first report to describe the breeding of a Tartary buckwheat cultivar with reduced rutin hydrolysis and no bitterness in the prepared flour. Notably, the agronomic characteristics of ‘Manten-Kirari’ were similar to those of ‘Hokkai T8’, which is the leading variety in Japan. Based on these characteristics, ‘Manten-Kirari’ is a promising for preparing non-bitter, rutin-rich foods.     

Effects of auxins on soluble carbohydrates,starch and soluble protein content in Aechmea blanchetiana (Bromeliaceae) cultured in vitro

We investigated the content of soluble carbohydrates, starch and soluble proteins after treatment with auxins indole-3-butylic acid (IBA) and 1-naphthaleneacetic acid (NAA) during the development of Aechmea blanchetiana (Bromeliaceae) plantlets cultured in vitro, to determine the contribution of these compounds in plant propagation. Fresh and dry mass of roots increased more than fivefold with NAA (5.37 and 16.11 μM) compared to those with the auxin-free control. After 70 days of culture concentration of soluble protein concentration content was higher in the roots and leaves of plantlets treated with IBA and similar to auxin-free control, while a maximum accumulation of sugars was observed at 90 days in the roots of plantlets treated with NAA (0.54 μM) or IBA (0.49 and 4.9 μM). The major carbon reserves in the roots were soluble carbohydrates, suggesting that they play an important role in the growth of in vitro-cultured epiphytic bromeliads.     

Spatial distribution of spawning redds and larvae of Rhinogobius flumineus in relation to hydrogeomorphological characteristics in Kamo River,Japan

Paddy and Water Environment - A freshwater goby, Rhinogobius flumineus, is one of the dominant species in the Kamo River and the Takano River, Kyoto City, Japan. We investigated the spatial...     

Temperature effects on sex differentiation of the reciprocal hybrids of Odontesthes bonariensis and Odontesthes hatcheri (Atherinopsidae)

The pejerrey Odontesthes bonariensis (Valenciennes 1835) and the Patagonian pejerrey Odontesthes hatcheri (Eigenmann 1909) are Atherinopsid species with commercial importance and potential for aquaculture. The hybrids of the two species are viable but their mode of sex determination is unknown. This study examined the gonadal histology and sex ratios of reciprocal hybrids that were reared at 15, 17, 21, 25 or 29 °C during the sex differentiation period. The genetic sex of hybrids from O. hatcheri fathers was inferred from a sex‐linked SNP marker. Both hybrids showed female‐biased sex ratios at the lowest temperature, female‐biased to balanced sex ratios at intermediate temperatures and balanced or male‐biased sex ratios at 29 °C, but unlike in purebred O. bonariensis, the lowest and highest temperatures did not yield monosex populations. The proportion of females in the offspring was affected more by parental genome than by hybrid combination. Female hybrids bearing the O. hatcheri Y chromosome showed temporary arrest of ovarian development that was rescued in adults. These results reveal strong interactions between genotype and temperature for sex determination and differentiation of the hybrids and provide important clues to understand the mechanisms of sex determination in these species.