Showing papers by "Kagawa University published in 1975"
TL;DR: Attempts were made to elucidate the acetyl transformation of novel trichothecene mycotoxins, 3a,7a,15-trihydroxy-12,13-epoxytrichotheC-9-en-8-one (deoxynivalenol) and its derivatives, by trichothcene-producing strains of Fusarium nivale, F. roseum, and F. solani.
Abstract: Attempts were made to elucidate the acetyl transformation of novel trichothecene mycotoxins, 3α,7α,15-trihydroxy-12,13-epoxytrichothec-9-en-8-one (deoxynivalenol) and its derivatives, by trichothecene-producing strains of Fusarium nivale, F. roseum, and F. solani. In the peptone-supplemented Czapek-Dox medium, F. roseum converted 3α-acetoxy-7α,15-dihydroxy-12,13-epoxytrichothec-9-en-8-one (3-acetyldeoxynivalenol) to deoxynivalenol. 3-Acetyldeoxynivalenol was also deacetylated by intact mycelia of the three strains in sugar-free Czapek-Dox medium. The growing F. nivale acetylated deoxynivalenol to afford a small amount of 3-acetyldeoxynivalenol. 3α,7α,15-Triacetoxy-12,13-epoxytrichothec-9-en-8-one (deoxynivalenol triacetate) was transformed by the intact mycelium of F. solani into 7α,15-diacetoxy-3α-hydroxy-12,13-epoxytrichothec-9-en-8-one (7,15-diacetyl-deoxynivalenol), which was then deacetylated to give 7α-acetoxy-3α,15-dihydroxy-12,13-epoxytrichothec-9-en-8-one (7-acetyldeoxynivalenol). It was noted that the ester at C-7 was not hydrolyzed by the fungal mycelium.
61 citations
TL;DR: An arabinanase was purified from the culture fluid of Bacillus subtilis F-11 and demonstrated to be homogeneous by disc electrophoresis and released arabinose, arabinobiose,Arabinotriose and higher oligosaccharides during the course of hydrolysis of 1,5-arabinan.
50 citations
TL;DR: It is proposed that in the Shokan 1-race 226 host-parasite system, the initial determinative events for resistance are induced independently from the process of host cell collapse, andhost cell collapse has no determinative role in the expression of resistance.
Abstract: The relationship between expression of resistance and host cell collapse was studied for the hypersensitive resistance of oat cultivar Shokan 1 infected by incompatible race 226 of Puccinia coronata avenae. Microscopic examination of primary leaves of seedlings treated by several methods involving heat treatment, stem detachment and double inoculation indicated that initial events determining the host resistance occurred between 8 and 12 h after inoculation, when the fungus produced substomatal vesicles. The initial events were followed by the reduction of growth of infection hyphae to half that in susceptible leaves. During the period of prehaustorial growth of the fungus, neither host cell collapse at infected sites nor permeability increase of leaf tissues was observed. The cessation of hyphal growth and haustorial development appeared to be normally concomitant with host cell collapse at 35 h after inoculation. However, study of leaves treated with blasticidin S or ethidium bromide or heat revealed that the limitation of fungal development in resistant reactions was not correlated with the degree of host cell collapse. The development of a normally compatible race was restricted without any collapse of mesophyll cells when the leaves were previously inoculated with the incompatible race and then heated. We propose that in the Shokan 1-race 226 host-parasite system, the initial determinative events for resistance are induced independently from the process of host cell collapse. Host cell collapse, although a normal consequence of the resistant reaction, therefore has no determinative role in the expression of resistance of Shokan 1 leaves to race 226.
32 citations
TL;DR: The morphological observation shows that the P. L. B. formed on explants may be derived from epidermal cell (or cells) or cells just below epidermis, and can be tolerably recovered by means of etiolation of stock plant.
Abstract: The present studies were carried out in order to establish the method of clonal propagation by leaf tissue culture in Phalaenopsis and Vanda. 1. Tissues cultured were the leaf segments of dimensions 8-10X 8~lOmm excised from young seedlings and matured plants of the both orchids, as well as the leaf tip of 5~7mm in length from infant seedlings of Vanda and the whole leaf of 8tilOmm in length from those of Phalaenopsis. The tissues were cultured under light on agar media containing various components, and the subsequent formation of protocorm-like bodies (P. L. B.) on the explants wass observed. The first external sign of cellular activity in explants was the appearance of a tiny protuberance to the tissue. The protuberance was seemed to be a primordium of P.L.B. 2. It was observed that the young leaf tissue from infant seedlings of Phalaenopsis and Vanda formed the P. L. B. easily by aseptic culture. In that, the P. L. B. were formed on the adaxial surface just above the basal cut-end of the explant in Vanda and on the surface of adaxial side in Phalaenopsis. 3. In both orchids, the proximal tissue of a leaf formed the P. L. B. more easily than the distal one. 4. The ability of the P. L. B. formation was high in the explant of infant seedlings, though a low ability was observed when the explant was excised from a seedling advanced in age. The lowering of the ability with aging of seedling was shown more clearly in Vanda than in Phalaenopsis. 5. The reduced ability of the P. L. B, formation in the eyplant from matured plants of Phalaenopsis can be tolerably recovered by means of etiolation of stock plant. The tissue from an unexpanded distal part of the etiolated leaf formed primordia of the P. L. B. fairly well. The primordia may develop into the P. L. B. after culturing in succession. 6. The result of the morphological observation shows that the P. L. B. formed on explants may be derived from epidermal cell (or cells) or cells just below epidermis. 7. As a practical medium for the P. L. B. formation, the following recipe will be recommended.
26 citations
TL;DR: In this article, Zhao et al. found that peak viscosity was not linearly related to amylose content, but was correlated with the gel consistency of rice starch.
Abstract: In the alkaliviscogram of starch of 26 nonwaxy rices grown in the tropics, gelatinization normality correlated positively with final gelatinization temperature (BEPT) of starch (r=0.969**) and negatively with alkali spreading value of milled rice (r= −0.931**). Peak viscosity was not linearly related to amylose content. Among samples of rice starch having a high amylose (>28%) content, peak viscosity was correlated with the gel consistency of starch (r=−0.690**) and of milled rice (r=−0.644**) (n = 18). These high-amylose starches showed the widest variation in peak viscosity. Amylose content, and gel consistency were inherited from the same parent in all nine varieties and lines studied, whereas peak viscosity, gelatinization normality and the final BEPT were inherited from either parent. The starch of five waxy rices showed higher peak viscosities even at a concentration of 1.8% as compared with a 2.0% nonwaxy rice starch.
22 citations
TL;DR: A pectate lyase was purified from the culture filtrate of Streptomyces fradiae by precipitation with ammonium sulfate and had macerating activity and was active on both native pectin and polygalacturonic acid, but the activity toward oligogalacturonides was small.
Abstract: A pectate lyase (EC 4. 2. 2. 2) was purified from the culture filtrate of Streptomyces fradiae by precipitation with ammonium sulfate, followed by column chromatography on DEAE-Sephadex A-50, SP-Sephadex C-50 and by gel-filtration on Sephadex G-100. The enzyme was an endo-pectate lyase with an optimum activity at pH 9.0_??_9.2, and required only calcium ion for the activity. The enzyme had macerating activity and was active on both native pectin and polygalacturonic acid, but the activity toward oligogalacturonides was small.
19 citations
TL;DR: The regio-selectivity in microbial modification of trichothecenes is demonstrated and mechanisms for biological modifications of these mycotoxins are postulated.
Abstract: The microbial modification of several trichothecene mycotoxins by trichothecene-producing strains of Fusarium nivale and F. solani was studied. These results were compared with the corresponding chemical modifications. The growing mycelia of Fusarium spp. did not convert 4beta-acetoxy-3alpha,7alpha, 15-trihydroxy-12, 13-epoxytrichothec-9-en-8-one (fusarenon) into 3alpha,4beta, 7alpha,15-tetrahydroxy-12,13-epoxy-trichothec-9-en-8-one (nivalenol), whereas 3alpha,4beta,7alpha,15-tetracetoxy-12,13-epoxytrichothec-9-en-8-one (tetraacetylnivalenol) was deacetylated to yield 3alpha-hydroxy-4beta,7alpha,15-triacetoxy-12,13-epoxytrichothec-9-en-8-one (4,7,15-triae-tylnivalenol), which was resistant to further deacetylation. T-2 toxin was transformed intoHT-2 toxin, and 8alpha-(3-methylbutyryloxy)-3alpha,4beta,-15-triacetoxy-12,13-epoxytrichothec-9-en-8-one (T-2 acetate) was transformed into HT-2 toxin via T-2 toxin. Chemical modification with ammonium hydroxide converted tetraacetylnivalenol into fusarenon via 4,7,15-triacetylnivalenol. 3alpha-7alpha,15-Triacetoxy-12,13-epoxytrichothec-9-en-8-one (triacetyldeoxynivalenol) gave deacetylation products lacking the C-7 or c-15 acetyl group in addition to 7alpha,15- diacetoxy-3alpha-hydroxy-12, 13-epoxytrichothec-9-en-8-one (7,15-diacetyldeoxynivalenol). These results demonstrate the regio-selectivity in microbial modification of trichothecenes. Based on the results and available knowledge concerning the transformation of trichothecenes, mechanisms for biological modifications of these mycotoxins are postulated.
19 citations
13 citations
TL;DR: Intact cells of a biotin-producing bacterium, KY–21–1–25, were found to synthesize biotin from dethiobiotin, but the biosynthesis of biotin by intact cells was strongly inhibited by the addition of adenine or adenosine.
Abstract: Intact cells of a biotin-producing bacterium, KY–21–1–25, were found to synthesize biotin from dethiobiotin. Optimal conditions for the biosynthesis of biotin from dethiobiotin by intact cells were investigated. Intact cells harvested from adenine-supplemented medium showed intensive biosynthesis. However, the biosynthesis of biotin by intact cells was strongly inhibited by the addition of adenine or adenosine. The inhibitory activity of adenine was about 10-fold greater than that of adenosine. Formation of several unidentified biotin-vitamers was observed in both reaction mixtures incubated with and/or without addition of adenine.
8 citations
6 citations
15 May 1975
TL;DR: In this paper, the authors reported that they had found that the majority of the participants were satisfied with the results of their experiments. But they did not specify the percentage of satisfied participants.
Abstract: モデル包装食品を用いて,蒸気-空気混合系加圧式レトルトによる伝熱解析を行ない,次のような結果を得た。(1) 用いたフィルム(全厚62-65μの2および3層ラミネートフィルム)では,フィルム差および,処理温度(105～120℃)の相違による,伝熱パラメーター,fの変動は無視できる。(2) 無限平板型試料での実験結果から,実用有効蒸気比の範囲(65-90%)では,表面伝熱係数(h)は1.13±0.05×10-2cal・cm-2・sec-1・deg-1であり,それ以下では,hは小さくなり,55%蒸気比では,0.826±0.117×10-2cal・cm-2・sec-1・deg-1である。(3) 実用型に近い,有限平板型試料での伝熱パラメーター,fは,実用条件である蒸気比65%以上で,試料厚さが2.5cmの試料で,特によく理論解で説明できた。
TL;DR: In this paper, the digestibility of crude fiber, cellulose and pentosan was measured in both cecum ligated and non-ligated chickens fed various kinds of diets.
Abstract: It has been asserted that a majority1) or a significant portion2, 3, 4) of crude fiber eaten by chickens is digested in the ceca. More recently, NAKAHIRO et al.5) demonstrated with chicks fed a semi-purified diet containing 12.5% fibrous screenings of Italian ryegrass that the digestibility of crude fiber, cellulose and pentosan was not affected by cecum ligation, and concluded that the cecum does not play an important role in the digestion of crude fiber in chickens.In order to verify the above-mentioned conclusion, the digestibility of crude fiber, cellulose and pentosan was measured in both cecum ligated and non-ligated chickens fed various kinds of diets.
TL;DR: Experiments indicated that the increase of rRNA was due to enhanced rRNA synthesis, not due to chloroplast rRNA, and no appreciable changes were shown for the synthesis of sRNA, tenaciously bound RNA and DNA.
Abstract: In leaves of Avena sativa infected by a compatible race of Puccinia coronata avenae , a rapid increase of ribosomal ribonucleic acid (rRNA) was found when the stem was excised 4 days after inoculation, at which time the fungus was in the beginning of differentiation toward uredosorus formation Concentrations increased up to 1·5-fold within 4 h after excision, while in the attached control the rRNA concentration increased gradually and reached the same level 16 h later Stem excision did not affect the concentration of soluble RNA (sRNA) and deoxyribonucleic acid (DNA) This selective increase of rRNA by stem excision was observed neither in the infected leaves 3 and 5 days after inoculation, nor in the noninoculated control leaves Experiments using [ 32 P]orthophosphate indicated that the increase of rRNA was due to enhanced rRNA synthesis No appreciable changes were shown for the synthesis of sRNA, tenaciously bound RNA and DNA Polyacrylamide gel electrophoretic separation of rRNA species revealed that the increase of rRNA was due to cytoplasmic rRNA and not due to chloroplast rRNA
TL;DR: D-arabinose and L-fucose can be identified and determined separately by this method and 1, 000-fold excess of following sugars and sugar alcohols do not interfere the determination of microquantity.
Abstract: A sensitive spectrophotometric method for qualitative and quantitative determination of D-arabinose and L-fucose in the 0.02_??_0.1 μmole range is described. Enzyme used for this assay is n-arabinose (L-fucose): NAD 1-oxidoreductase (EC. 1. 1. 1. 116) prepared from the D-arabinose-grown cells of Pseudomonas sp. The enzyme accepts either D-arabinose or L-fucose as substrate and is required NAD or NADP as coenzyme. D-Arabinose and L-fucose can be determined as the rate of NAD reduction at 340 nm at 30°C with reaction velocity method and end point method. This assay method is highly specific and 1, 000-fold excess of following sugars and sugar alcohols do not interfere the determination of microquantity (10-4M) of D-arabinose and L-fucose: L-arabinose, D-xylose, D-ribose, D-Iyxose, D-fucose, L-rhamnose, D-fructose, sucrose, xylitol, L-arabitol, D-arabitol, ribitol, sorbitol and D-mannitol. Moreover, L-fucose can be recovered in the presence of 4, 000-fold excess of D-galactose and D-mannose. D-Arabinose and L-fucose can be identified and determined separately by this method.
TL;DR: Formation of NAmRDPR proceeded stoichiometrically with degradation of NAD, but production of this compound was not demonstrated in other mold genera.
Abstract: Aspergillus niger (AKU 3302) degraded NAD to form Compound X. This compound was identified as nicotinamide ribose diphosphate ribose (NAmRDPR) by hydrolysis with alkaline or phosphodiesterase followed by chemical analysis of the products. NAmRDPR showed absorption maxima at 265~266 nm in 0.1 n HCI and 325 nm in 1.0 n KCN. Optimal pH for NAmRDPR formation by the enzyme preparation from this organism was around 4.0. Formation of NAmRDPR proceeded stoichiometrically with degradation of NAD. Some of other strains of A. niger formed NAmRDPR, but production of this compound was not demonstrated in other mold genera.
TL;DR: The results obtained are as follows: the feeding amount of the Himedaka showed a rapid rate of increase during 10 minutes from the beginning of experiment, and the social facilitation rate of female was higher than that of male.
Abstract: There are reported on the social facilitation of the feeding behavior in the Himedaka, Oryzias latipes. Before the experiment, each reacting fish was isolated in an aquarium without food, and then, transferred to an experimental basket, in which they were kept in quiet condition at least in an hour. Experimental apparatus was used the 2-cells basket (UEMATSU, 5). The stimulators (0, 1 and 3individuals) in one cell of the basket were shown for the reacting fish in opposite cell. At the beginning of experiment, 50 individuals of Daphnia pulex per a fish were given for the reacting fish. The feeding amount of fish was calculated at each observation time (10, 20, 40, 80 and 120 minutes).The results obtained are as follows : 1) The feeding amount of the Himedaka showed a rapid rate of increase during 10 minutes from the beginning of experiment. During other later period the value increased with almost constant speed, though the speed was low.2) The social facilitation in the feeding amount was clearly observed at each observation time.3) Female ate more heavily than male in almost all cases.4) The social facilitation rate (FR) increased with time, although the value was small during the later period (40-120 min.).5) The social facilitation rate of female was higher than that of male.
TL;DR: In this paper, a model for the massenproduktion einer Pflanzengesellschaft unter den naturlichen Bedingungen is presented, which is formuliert and numerisch ausgewertet.
Abstract: Ein Modell, welches die Massenproduktion einer Pflanzengesellschaft unter den naturlichen Bedingungen (vgl. Abb. 1) beschreibt, ist mathematisch formuliert und numerisch ausgewertet. Hierbei sind physikalische und okologische Gesetze kombiniert. Die Grundgleichung (15) ist auf den Blattflachenindex, auf Strahlungsintensitat und Temperatur reduziert. Schlieslich ist die Theorie auf die Verhaltnisse eines 70jahrigen Fichtenhochwaldes im Ebersberger Forst (γ=48°N, γ=11°E) angewandt.
TL;DR: In the vineyards where leaves have shed in every rainy season, the N and P contents decreased and the Cu content increased in the leaves at the basal part of bearing shoots with their growth, suggesting that the vein-yellowing symptom is closely related to the Cucontent of leaves which is affected through the change in soluble Cu content of soil.
Abstract: Vein-yellowing of leaves has often appeared at the basal part of shoots of the Campbell′s Early vines grown under wetting conditions during the rainy season in Kagawa prefecture, resulting in a serious damage for its production. To clarify the metabolic mechanism of this foliage disorder, the content of mineral nutrients was compared between the vein-yellowed leaves and the normally developed ones collected from other healthy vineyards.1.The vein-yellowed leaves contained less N and P, and more Cu than the normal leaves. Particularly, the upward and downward trends of the element content were marked with N in petiole and vein and with P and Cu in mesophyll.2. In the vineyards where leaves have shed in every rainy season, the N and P contents decreased and the Cu content increased in the leaves at the basal part of bearing shoots with their growth. This suggests that the vein-yellowing symptom is closely related to the Cu content of leaves which is affected through the change in soluble Cu content of soil.3. When pot-cultured vines were submerged at the root zone, rootlets turned black and died before long. In the leaf analysis at the basal part of shoots, the vines treated with excess water showed less N, P and K and more Mn, Fe and Cu contents than the non-treated vines. However, no marked difference of the mineral nutrient contents was observed with the leaf at the top part of shoots between both the treated and non-treated vines.
TL;DR: The results suggest that the activity of renal G6Pase of rats feeding the high protein diet might be less susceptible both to dietary calcium levels and to parathyroid function than that of rats fed the high carbohydrate diet.
Abstract: In order to determine the relationship of parathyroid hormone and levels of dietary protein and calcium with the activity of renal glucose-6-phosphatase (G6Pase), effects of two levels of dietary protein, namely, 25 and 75%, on the enzyme activity were compared at three levels of dietary calcium, namely, 0.06, 0.63, and 1.83%, with the use of intact and thyroparathyroidectomized (TPTX) rats. In intact rats, 0.06% dietary calcium caused an increase in renal G6Pase activity in rats fed the high carbohydrate diet, and dietary calcium in excess (1.83%) caused the enzyme activity to decrease. Similar responses in the activity of renal G6Pase to the variation of dietary calcium levels were seen in rats fed the high protein diet, but significant differences were not obtained. In TPTX rats fed the high carbohydrate diet, the activity of renal G6Pase was significantly decreased compared with that of intact rats. When TPTX rats were fed the high protein diet, however, no significant decrease in the enzyme activity was observed. Free access to aqueous 0.1% CaC1(2) solution by TPTX rats tended to restore the activity of renal G6Pase and serum calcium concentrations depressed by thyroparathyroidectomy. In addition, a significant correlation was observed between the total activity of renal G6Pase and serum calcium concentrations. Hypothyroidism produced by oral administration of propylthiouracil (0.05% of diets) did not affect the enzyme activity in the kidneys of rats fed the high carbohydrate and the high protein diets. The results suggest that the activity of renal G6Pase of rats fed the high protein diet might be less susceptible both to dietary calcium levels and to parathyroid function than that of rats fed the high carbohydrate diet.