Effects of Brief Summer or Winter Fasting on the Muscle Quality of Cultured Pacific Bluefin Tuna (Thunnus orientalis)

The effects of fasting on the quality of the dorsal and ventral ordinary muscles from cultured Pacific bluefin tuna (Thunnus orientalis) during chilled storage were investigated. Tuna were subjected to fasting for 2 days in the summer or 6 days in the winter prior to harvesting. The breaking strength of the dorsal ordinary muscle sampled in the summer increased until 24 h and then decreased. There were no significant differences in the lipid and glycogen content of the ordinary muscle after 9 h of storage between the controls and either fasting group. The pH of the ordinary muscle subjected to summer and winter fasting was higher than in the controls after 24–48 h of storage. However, the relationship between the pH and glycogen content was unclear. The metmyoglobin content during chilled storage was lower in the ordinary muscles from either fasting group than in the controls. In conclusion, fasting for 6 days in the winter improved the color stability of the ordinary muscle without a decline in its lipid content.     

Comparison of fertility on intrauterine insemination between cryopreserved ejaculated and cauda epididymal sperm in dogs

The fertility was compared between ejaculated and cauda epididymal sperm sensitized with prostatic fluid in dog after freeze-thawing using the fertility of ova from the contralateral ovary after injection (2 × 10(8) sperm) into dog uterus on the unilateral ovariectomized side, on the basis of the presence or absence of conception. No significant difference was observed in sperm quality after freeze-thawing between the two groups and conception rates were equivalent and low. Therefore, to achieve a high fertility by intrauterine insemination of canine frozen-thawed ejaculated and cauda epididymal sperm, intrauterine insemination on both sides is recommended, rather than insemination with a lot of sperm of the uterine horn on one side.     

Mapping a gene conferring resistance to <Emphasis Type="Italic">Wheat yellow mosaic virus</Emphasis> in European winter wheat cultivar ‘Ibis’ (<Emphasis Type="Italic">Triticum aestivum</Emphasis> L.)

Wheat yellow mosaic, caused by Wheat yellow mosaic virus (WYMV), is one of the most devastating soil-borne diseases of winter wheat (Triticum aestivum L.) in Japan. Yellow-striped leaves and stunted spring growth, symptomatic of WYMV infection, result in severe yield loss. A new putative WYMV resistance gene in the European wheat cultivar ‘Ibis’ was mapped in the cluster of microsatellite markers including Xcfd16, Xwmc41, Xcfd168 and Xwmc181 on the long arm of chromosome 2D at the distances of 2.0 cM, 4.0 cM, 7.1 cM and 12.4 cM, respectively. WYMV-resistant cultivars contained a common haplotype of the four markers, whereas moderately susceptible and susceptible cultivars did not. These results should be useful in marker-assisted selection for WYMV resistance in wheat.     

Black tea polyphenols, theaflavins, prevent cellular DNA damage by inhibiting oxidative stress and suppressing cytochrome P450 1A1 in cell cultures.

Tea polyphenols have been demonstrated as chemopreventive agents in a number of experimental models. However, less is known about the mechanism of chemoprevention by black tea compared with that of green tea. Some beneficial properties of theaflavins, the black tea polyphenols, were investigated in the present study. Theaflavins showed inhibitory effects on H(2)O(2)- and tert-butyl hydroperoxide (tBuOOH)-induced cytotoxicity (evaluated by tetrazolium bromide reduction), cellular oxidative stress (detected by oxidation of 2', 7'-dichlorofluorescin), and DNA damage (measured by amount of 8-OHdG and comet assay) in rat normal liver epithelium cell RL-34 cell lines. In addition, theaflavins also exhibited suppression of cytochrome P450 1A1 induced by omeprazole in the human hepatoma HepG2 cell line. Furthermore, when HepG2 cells were pretreated with omeprazole to induce CYP1A1, then exposed to benzo[a]pyrene (B[a]P), DNA damage was observed using the comet assay. However, theaflavins could inhibit this DNA damage. These results indicated that theaflavins could prevent cellular DNA damage by inhibiting oxidative stress and suppressing cytochrome P450 1A1 in cell cultures.     

Effect of jasmonates on ethylene biosynthesis and aroma volatile emission in Japanese apricot infected by a pathogen (Colletotrichum gloeosporioides)

The effects of the application of the jasmonic acid derivative n-propyl dihydrojasmonate (PDJ) on ethylene biosynthesis, volatile compounds, and endogenous jasmonic acid (JA) and methyl jasmonate (MeJA) were examined in Japanese apricot (Prunus mume Sieb.) infected by a pathogen (Colletotrichum gloeosporioides). The fruit were dipped into 0.4 mM PDJ solution before inoculation with the pathogen and stored at 25 °C for 6 days. The inoculation induced an increase in 1-aminocyclopropane-1-carboxylic acid (ACC), ethylene, JA, and MeJA. In contrast, PDJ application reduced the endogenous JA, MeJA, and ethylene production and expression of the ACC oxidase gene (PmACO1) caused by the pathogen infection. The lesion diameter with C. gloeosporioides decreased upon PDJ application. The alcohol, ester, ketone, and lactone concentrations and alcohol acyltransferase (AAT) activity increased in the pathogen-infected fruit, but were decreased by PDJ application. These results suggest that PDJ application might influence ethylene production through PmACO1 and that aroma volatile emissions affected by pathogen infection can be correlated with the ethylene production, which is mediated by the levels of jasmonates.     

Production of ascorbic acid enriched vegetables: Absorption of an L-ascorbic acid solution and the effect of storage temperature on the foliar exogenous ascorbic acid content

Summary

An economic assessment was made of whether leaf vegetables can absorb almost all of a given amount of an L-ascorbic acid solution applied by soaking the roots for 12 h. The effects of storage temperature on the foliar exogenous ascorbic acid content were also observed. It was found that the given amounts of L-ascorbic acid solution are entirely absorbed by lettuce plants (Lactuca sativa L., cv. Redfire) and are over 90% absorbed by spinach (Spinacio olerácea L., cv. Read) and bunching onion plants (Allium fistulosum L., cv. Hakata Kuronegi). Due to the soaking treatment, the sum of the L-ascorbic acid (AA) and dehydro-ascorbic acid (DHA) contents (mg per 100 g fresh weight) in the leaves of plants which showed no signs of wilting increased from 38.9 to 201–221 in lettuce, from 76.5 to 196–225 in spinach and from 46.7 to 134–144 in bunching onion. The foliar AA content in all the plants stayed at approximately the same value during a storage period of 7 d at 4°C, but decreased significantly at 25°C. The foliar DHA content in all of the plants stayed at approximately the same value during storage at both 4 and 25°C. These results suggest that the ascorbic acid introduced into leaf vegetables can be used effectively by consumers when the vegetables are stored at low temperature.     

Effects of bulb desiccation and storage on the in vitro propagation of hyacinth

The effect of long-storage and silica gel desiccation of hyacinth bulbs (Hyacinthus orientalis L.) on in vitro bulblet formation was investigated.Bulbs of 3 cultivars were stored at 25°C and 50–60% relative humidity for 17 months. This long-term storage of bulbs markedly enhanced bulblet initiation from scales and growth of regenerated bulblets.Bulbs of 5 cultivars were desiccated with silica gel for 5 and 20 h before in vitro propagation. The total number of bulblets increased as a result of 5 h desiccation with silica gel. Bulb desiccation for 20 h caused a large increase in the growth rate of bulblets. This desiccation treatment with silica gel is a practical method to obtain many and more regenerative explants in the in vitro propagation of hyacinth.     

Evaluation of aroma compounds contributing to muskmelon flavor in Porapak Q extracts by aroma extract dilution analysis

The flavor of the Miyabi variety of Japanese muskmelon was extracted according to the Porapak Q column method (PQM) and evaluated by using aroma extract dilution analysis (AEDA) method. The overall odor of the PQM extracts was perceived as having a natural muskmelon-like odor, suggesting that the PQM was able to extract volatile compounds in muskmelon fruit without degradation of original flavor. Forty-six odorant compounds [Kovats index (KI), 961 < or = KI < or = 2605] were found by GC-sniffing in PQM extracts, confirming the effectiveness of PQM in trapping a wide range of volatile compounds in muskmelon flavor. The 46 odorants could be divided into three groups on the basis of their odor attributes: fruity note (KI < 1300); green, grassy, or cucumber-like note (1300 < KI < 2020); and sweet note (KI > 2020). When the original extracts were diluted in AEDA analysis, seven odorants could still be detected by GC-sniffing at a flavor diluation (FD) factor of 128 or above: one had a fruity note (compound 3); four had a cucumber-like, green, or grassy note (compounds 12, 17, 21, and 23); and two had a sweet note (caramel-like or yakitori-like) (compounds 32 and 34).     

Application of the porapak q column extraction method for tomato flavor volatile analysis

The Porapak Q column method (PQM) was compared to the method of simultaneous distillation extraction (SDE) under reduced pressure for extraction of the volatile compounds produced by tomato cv. Momotaro. The PQM was found to be effective at trapping and isolating many low and high boiling point volatile compounds and at producing the very desirable natural ripe tomato flavor of extracts. The SDE method was less effective in isolating the higher boiling point volatile compounds and caused deterioration of volatile compounds due to the heating process that takes place during extraction, resulting in an unpleasant boiled green tomato flavor of extracts. The advantages of using the PQM are its simplicity and its high efficiency in isolating many volatile compounds from nonvolatile materials at room temperature. A total of 367 volatile compounds were isolated by the PQM. Of these, hexanal, (Z)-3-hexenal, (E)-2-hexenal, 2- and 3-methylbutanol, and 2-phenylethanol were relatively more abundant than other compounds and (Z)-3-hexenal showed the highest relative amount.     

Inhibition of hepatitis C virus replication and viral helicase by ethyl acetate extract of the marine feather star Alloeocomatella polycladia

Hepatitis C virus (HCV) is a causative agent of acute and chronic hepatitis, leading to the development of hepatic cirrhosis and hepatocellular carcinoma. We prepared extracts from 61 marine organisms and screened them by an in vitro fluorescence assay targeting the viral helicase (NS3), which plays an important role in HCV replication, to identify effective candidates for anti-HCV agents. An ethyl acetate-soluble fraction of the feather star Alloeocomatella polycladia exhibited the strongest inhibition of NS3 helicase activity, with an IC(50) of 11.7 μg/mL. The extract of A. polycladia inhibited interaction between NS3 and RNA but not ATPase of NS3. Furthermore, the replication of the replicons derived from three HCV strains of genotype 1b in cultured cells was suppressed by the extract with an EC(50) value of 23 to 44 μg/mL, which is similar to the IC(50) value of the NS3 helicase assay. The extract did not induce interferon or inhibit cell growth. These results suggest that the unknown compound(s) included in A. polycladia can inhibit HCV replication by suppressing the helicase activity of HCV NS3. This study may present a new approach toward the development of a novel therapy for chronic hepatitis C.