Ferrochelatase catalyzes the formation of Zn-protoporphyrin of dry-cured ham via the conversion reaction from heme in meat

Ferrochelatase (FECH), the enzyme at the last step of the heme-biosynthetic pathway, is involved in the formation of Zn-protoporphyrin via an iron-removal reaction of heme. To improve the efficacy of the formation of Zn-protoporphyrin from heme, the use of recombinant FECHs from porcine, yeast, and bacteria was examined. Incubation of FECH with myoglobin in the presence of ascorbic acid and cysteine resulted in the efficient conversion of myoglobin-heme to Zn-protoporphyrin. Exogenously added recombinant yeast FECH facilitates the production of Zn-protoporphyrin from myoglobin-heme and heme in meat, via the replacement of iron in the protoporphyrin ring by zinc ions. A large amount of Zn-protoporphyrin was also generated by the catalysis of FECH using an intact piece of meat as a substrate. These findings can open up possible approaches for the generation of a nontoxic bright pigment, Zn-protoporphyrin, to shorten the incubation time required to produce dry-cured ham.     

Strawberry cultivar identification based on hypervariable SSR markers

We genotyped strawberry cultivars by two newly selected and two previously reported SSR markers. All four markers produced interpretable electropherograms from 75 accessions consisting of 72 Fragaria × ananassa cultivars or lines and three octoploid Fragaria species accessions. These SSR markers were highly polymorphic; in particular, one of the newly developed markers, FxaHGA02P13, was capable of distinguishing all of the accessions except for a mutant strain that was derived from another accession in the set. When two markers were combined, all 48 full-sib individuals could be distinguished. Fingerprinting patterns were reproducible between multiple samples, including the leaves, sepals, and fruit flesh of the same accession. Principal-coordinate analysis of the 75 accessions detected several groups, which reflect taxon and breeding site. Together with other available markers, these SSR markers will contribute to the management of strawberry genetic resources and the protection of breeders’ rights.     

Improvement of dimensional stability and weatherability of composite board made from water-vapor-exploded wood elements by liquefied wood resin impregnation

High-density and high-resin-content boards were produced by phenolic resin impregnation into board materials prepared by the water-vapor-explosion process (WVE) to develop high-durability wood composite boards for exterior use. Wet-dry cyclic tests and accelerated weathering tests were conducted, and the fundamental properties were determined to examine the effect of resin impregnation on board qualities. Bending and internal bond strength of resin-impregnated boards (I-board) satisfied the criterion for 18-type particleboard described in JIS A 5908. Thickness swelling (TS) after 24-h water immersion was approximately 2%. Resin impregnation improved the dimensional stability of the boards. In wet—dry cyclic testing, TS of I-board was the same as that of plywood. The retention ratio of modulus of rupture of I-board was large; thus, I-board had high bond durability. Color change of I-board was less than that of ordinary particleboard after a 500-h accelerated weathering test. I-Board had lower surface roughness than boards produced by a spray application method (S-board) and higher water repellency, although the difference in resin contents of the face layer was small. Thus, it is suggested that the surface properties and weatherability of I-board were improved by impregnation of phenolic resin. High-density and resin-impregnated boards made from the WVE elements are expected to withstand actual exterior use. Part of this report was presented at the 54th Annual Meeting of the Japan Wood Research Society, Sapporo, August 2004     

Physicochemical properties of pseudorabies virus hemagglutinin.

Pseudorabies virus hemagglutinin was readily adsorbed on mouse erythrocytes at 4, 22, or 37 degrees C, but not on cattle erythrocytes. The adsorbed hemagglutinin could not be eluted from the cells by resuspending in phosphate-buffered saline (PBS), by incubating at 37 or 50 degrees C, or by incubating in the presence of neuraminidase. The receptor on mouse erythrocytes for the hemagglutinin was inactivated by trypsin, but not by neuraminidase, sodium deoxycholate (DOC), potassium periodate (KIO4), dithiothreitol (DTT), 2-mercaptoethanol (2-ME) and formalin. The hemagglutinin was inactivated by trypsin, alpha-amylase, pepsin, DOC, KIO4, and ethylendiamine-tetraacetic acid (EDTA), but not by papain, beta-glucosidase, phospholipase C, neuraminidase, DTT, 2-ME, Tween-80, ethylether, chloroform, trichloro-trifluoroethane, beta-propiolactone and formalin, suggesting that the hemagglutinin active component involved glycoproteins. The hemagglutinin was stable at 37 degrees C for lower temperatures but not at 60 degrees C or higher. The hemagglutinin activity was resistant to ultraviolet irradiation, while the infectivity was very susceptible. The hemagglutinin and the infectivity were readily sedimented by ultracentrifugation at 48,000 x g for 3 hr. In rate zonal centrifugation of the preparation on a sucrose density gradient, the hemagglutination (HA) activity showed a sharp peak at 1.22 g/ml coinciding with the peak of infectivity. The HA activity in the peak fraction seemed to be structually associated with virus particles. After fractionation of the virus by Nonidet P-40, the HA activity was found only in the fraction of the envelope material, indicating that the hemagglutinin is situated in the viral envelop.     

High performance liquid chromatographic determination of trimethoprim residues in egg yolk and albumen in a feeding experiment

In a feeding experiment, the residues of trimethoprim (TMP) in egg yolk and albumen were determined by high performance liquid chromatography (HPLC). Laying hens were divided into four groups. The first group was designated as control and fed with TMP free diet during the experimental period. The second, third and fourth groups were administered with the feeds containing 4 p.p.m., 16 p.p.m. and 56 p.p.m. TMP, respectively, for 19 days and, thereafter, fed with TMP free diet. TMP was mainly found in yolk in all the three administered levels. In the medication period, the average concentration of TMP in the yolk of the second, third and fourth groups was 0.05, 0.25, and 0.90 p.p.m., respectively. After withdrawal of medication, the residues of TMP in yolk in the second, third and fourth groups decreased below the detection limit at 0.02 p.p.m. on days 4, 9, and 11, respectively.     

The biological activities of cardenolide triglycosides from stems, twigs, and leaves of Nerium oleander

Sixteen cardenolide triglycosides (1?C16) were isolated from stems, twigs, and leaves of Nerium oleander. Among them, 3??-O-(4-O-gentiobiosyl-d-diginosyl)-7??,8-epoxy-14-hydroxy-5??,14??-card-20(22)-enolide, named cardenolide B-3 (16), was isolated from natural sources for the first time. The in vitro anti-inflammatory activities of compounds 1?C16 were examined on the basis of inhibitory activity against the induction of intercellular adhesion molecule-1 (ICAM-1). Compounds 1?C5 were active at an IC50 value of less than 7 ??M. The cytotoxic activity of isolated compounds was evaluated against three human cell lines: normal human fibroblast cells (W-38), malignant tumor cells induced from WI-38 (VA-13), and human liver tumor cells (HepG2). Compounds 1?C5 were active toward WI-38 cells; compounds 1, 3, and 5 were active toward VA-13 cells; and compounds 1?C5 were active toward HepG2 cells at IC₅₀ values of less than 10 ??M. The multidrug-resistant (MDR) cancer-reversal activity of compounds 1?C16 was evaluated on the basis of the amount of calcein accumulated in MDR human ovarian cancer 2780AD cells in the presence of each compound. Compounds 13 and 14 showed significant effects on calcein accumulation.     

Capsule thickness and amounts of a 39 kDa capsular protein of avian Pasteurella multocida type A strains correlate with their pathogenicity for chickens

Capsule thickness of avian Pasteurella multocida type A strains was determined by transmission electron microscopy after labeling with polycationic ferritin and compared with their pathogenicity for chickens. The capsule thickness of P. multocida strains Pm-18 and X-73 was 81.4 and 50.1 nm on average, respectively. These strains were highly virulent for chicken, whereas the less virulent strains Pm-1 and Pm-3 had a thin and irregular capsule, 21.0 and 29.8 nm on average, respectively. However, the thickest capsule was observed in strain P-1059, 101.2 nm on average, and the strain revealed moderate virulence. The noncapsulated variant P-1059B, which was derived from strain P-1059, revealed low virulence. The six P. multocida strains were examined with regard to protein content on the capsule of organisms. Amounts of total proteins of crude capsular extract (CCE) from capsulated strains were approximately twice those of the noncapsulated strains. The amount of an antigenic 39 kDa protein in the CCE were found to correlate with the capsule thickness, since heavily capsulated strains exhibited the greatest amount, whereas noncapsulated strains including noncapsulated and low virulent variant P-1059B possessed little 39 kDa protein. The results demonstrated that the capsule thickness and the quantity of a 39 kDa capsular protein of avian P. multocida type A strains correlated with their pathogenicity for chickens.     

Babesia microti-like parasites detected in Eurasian red squirrels (Sciurus vulgaris orientis) in Hokkaido, Japan

Six Eurasian red squirrels (Sciurus vulgaris orientis), victims of road traffic found during 2002 and 2004 near the Noppro Forest Park in Ebetsu, Hokkaido, Japan, were examined for the presence of Babesia parasites. Three of the six squirrels exhibited positive signals by nested PCRs targeting both the 18S rRNA and beta-tubulin genes. Three squirrels proved to be infected with a B. microti-like parasite as evidenced by sequencing the amplified DNAs and by the morphology of the intraerythrocytic parasites. Genotypically, however, the parasite appeared to be of a new type, as it was clearly distinguishable from any of the known types that have previously been reported in various wild animals. This is the first report showing molecular evidence for the presence of B. microti-like parasites in Sciuridae.     

Weatherability and combustibility of fire-retardant-impregnated wood after accelerated weathering tests

The weatherability and combustibility of fireretardant-impregnated wood during accelerated weathering for up to 2000 h were evaluated. The ability of coating to retain fire-retardant chemicals against leaching was also examined using four coating systems (water-borne or solvent-borne, pigmented or clear, film-forming or penetrating). Furthermore, the distribution of fire retardants in the specimens was observed by scanning electron microscopy in combination with energy dispersive analysis of Xrays (SEM-EDX). The fire performance of the specimens during weathering depended on the chemical retention, and was maintained at a quasi-noncombustible material level if the chemical retention was above 150 kg/m³. The maximum duration of accelerated weathering to keep this retention was 250 h for the uncoated specimens, but increased to over 1000 h for pigmented coatings. SEM-EDX revealed that the fire retardants were accumulated in the cell lumina throughout the wood tissues. However, in the uncoated samples, the leaching of fire retardants occurred for surfaces exposed to light and water, and was observed down to a depth of ∼150 μm after 500 h. The leaching depth extended throughout the specimen after 1000 h. In contrast, the fire retardants still remained in samples finished with a solvent-borne pigmented penetrating coating even after 1000 h due to their relatively high chemical retention.