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We investigated the content of phenolic compounds and antioxidant capacity of two batches of non-heated and heated leaves of the yacon cultivar “Andes no yuki”, grown in Japan. Lyophilized yacon leaves heated at 160°C for 20 min and 100°C for 60 min had a 1.96 to 9.69-times higher total phenolic content than that of the non-heated leaves. Heated leaves exhibited a 1.98 to 4.07-times higher antioxidant capacity than that of the non-heated leaves in three different free radical scavenging assays. Heated leaves were more efficient at attenuating the superoxide anion radical production in human granulocytic cells than the non-heated leaves. High-performance liquid chromatography analysis revealed that, in the heated leaves, the caffeic acid content was 2.13 to 3.64-times higher and the chlorogenic acid content was slightly lower than those in the non-heated leaves. Hence, heat processing may affect the active constituent contents in yacon leaves, potentiating its antioxidant capacity. Abbreviations: ABTS+: 2,2′-azinobis(2-ethylbenzothiazoline-6-sulfonic acid) cation; DPPH: 1,1-diphenyl-2-picrylhydrazyl, HPLC: high-performance liquid chromatography; NBT: nitroblue tetrazolium; O2−: superoxide anion; PMA: phorbol 12-myristate 13-acetate; PMS: phenazine methosulfate; TEAC: Trolox equivalent antioxidant capacity

We investigated the content of phenolic compounds and antioxidant capacity of two batches of non-heated and heated leaves of the yacon cultivar "Andes no yuki", grown in Japan. Lyophilized yacon leaves heated at 160°C for 20 min and 100°C for 60 min had a 1.96 to 9.69-times higher total phenolic content than that of the non-heated leaves. Heated leaves exhibited a 1.98 to 4.07-times higher antioxidant capacity than that of the non-heated leaves in three different free radical scavenging assays. Heated leaves were more efficient at attenuating the superoxide anion radical production in human granulocytic cells than the non-heated leaves. High-performance liquid chromatography analysis revealed that, in the heated leaves, the caffeic acid content was 2.13 to 3.64-times higher and the chlorogenic acid content was slightly lower than those in the non-heated leaves. Hence, heat processing may affect the active constituent contents in yacon leaves, potentiating its antioxidant capacity.

UNLABELLED Yacon (Smallanthus sonchifolius), a native Andean plant, has been cultivated as a crop and locally used as a traditional folk medicine for the people suffering from diabetes and digestive/renal disorders. However, the medicinal properties of this plant and its processed foods have not been completely established. This study investigates the potent antioxidative effects of herbal tea leaves from yacon in different free radical models and a ferric reducing model. A hot-water extract exhibited the highest yield of total polyphenol and scavenging effect on 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical among four extracts prepared with hot water, methanol, ethanol, and ethylacetate. In addition, a higher reducing power of the hot-water extract was similarly demonstrated among these extracts. Varying concentrations of the hot-water extract resulted in different scavenging activities in four synthetic free radical models: DPPH radical (EC50 28.1 μg/mL), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) cation radical (EC50 23.7 μg/mL), galvinoxyl radical (EC50 3.06 μg/mL), and chlorpromazine cation radical (EC50 475 μg/mL). The yacon tea-leaf extract further demonstrated superoxide anion (O2(-)) radical scavenging effects in the phenazine methosulfate-NADH-nitroblue tetrazolium (EC50 64.5 μg/mL) and xanthine oxidase assay systems (EC50 20.7 μg/mL). Subsequently, incubating human neutrophilic cells in the presence of the tea-leaf extract could suppress the cellular O2(-) radical generation (IC50 65.7 μg/mL) in a phorbol 12-myristate 13-acetate-activated cell model. These results support yacon tea leaves may be a good source of natural antioxidants for preventing O2(-) radical-mediated disorders. PRACTICAL APPLICATION Yacon has been considered to be a potent alternative food source for patients who require a dietary cure in regional area, while the leaf part has been provided and consumed as an herbal tea in local markets. We demonstrated here potent antioxidative effects of the tea leaves from yacon in different free radical assays, reducing power assay, and cellular superoxide anion radical generation assay. Results support yacon tea leaves may be a good source of natural antioxidants for preventing O2(-) radical-mediated disorders.

Sixty RAPD primers of random amplified polymorphic DNA (RAPD) were used to investigate genetic difference, and to evaluate DNA finger printing patterns to develop molecular markers in three cultivars among the locally-isolated and the Higo-giku group in Chrysanthemum X morifolium such as ‘Kinkujaku', ‘Madonotsuki' and ‘Nowake' never allowed to be taken out of Kumamoto Prefecture, Japan. Different primers amplified varying numbers of DNA fragments, and altogether 353 reproducible DNA fragments were totally amplifi ed. The generated bands of DNA fragments were in the range of 300-8000 bp in ‘Kinkujaku', 200-8000 bp in ‘Madonotsuki', and 350-8000 bp in ‘Nowake'. Each primer of OPA-06, OPA-14, OPC-18 and OPC-20 revealed one band with no polymorphic DNA fragment among all cultivars studied here. Sixty-two and 48 bands generated by RAPD primers were specific to ‘Kinkujaku' and ‘Madonotsuki', respectively. In contrast, 26 bands were specific to ‘Nowake', and were generated by 21 primers. Pairwise test showed that the three cultivars of the Higo-giku group.

A karyomorphological characterization of Polytrias amaura (Poaceae) was performed using orcein staining, sequential fluorescent staining with chromomycin A3 (CMA) and 4',6-diamidino-2-phenylindole (DAPI), and fluorescence in situ hybridization (FISH) method. The common somatic complement with 20 chromosomes were observed in all metaphase cells analyzed. Mitotic chromosomes in respective chromosome complement showed a gradual decrease in size from the largest to the smallest chromosomes. The largest and the smallest chromosome lengths at metaphase were 3.5 μm and 2.0 μm, respectively. The fluorochromes of CMA and DAPI gave reproducible condensation pattern to every prometaphase chromosome, but not metaphse. Each chromosome displayed a characteristic condensation pattern, which was quite same between differential staining methods of GC-specific CMA and AT-specific DAPI. In FISH, two bright 5S rDNA signals were detected at interstitial region of the chromosomes.

Yacon (Smallanthus sonchifolius) is known as a root crop rich in fructans and polyphenol. In the present study, the effects of yacon silage (YS) on body weight change, digestibility of feed, blood characteristics and level of urinary 8-hydroxydeoxyguanosine (8-OHdG) in ewes were evaluated. Ewes were fed basal diets (40% of soybean curd residue silage (SS) on a dry matter [DM] basis) supplemented with 60% of YS (YS group) or bermudagrass (Cynodon dactylon) hay (BH; BH group) on a DM basis for 36 days. YS did not influence the ewes’ body weight or digestibility of feed. The serum concentrations of total protein, glucose and total cholesterol of the YS group were significantly lower than those of the BH group (P

Yacon (Smallanthus sonchifolius [Poepp. & Endl.] H. Robinson) plant cultivation has extended rapidly throughout Japan since 1985 because of its utility as a tuberous root crop. In this study, strains with high yields of both above-ground and underground parts were identified to investigate the use of above-ground parts for animal feed silage. In addition, we measured the anti-oxidative activity of the silage as a functional characteristic. Data from 5 years of the cultivation of 17 yacon strains suggest that the most suitable strain for planting in the Aso region of Japan is SY217, which has a high yield of both above-ground parts and tuberous roots. The root tuber parts of yacon are used almost entirely as food; actually, most foliage parts are hardly used, except for some above-ground parts, which are used as tea. The fermentation qualities of the silage using all above-ground parts and harvest residue tuberous roots (harvest residues) are high and their dry matter digestibility, investigated using pigs, is 66.7%. Fresh above-ground parts had very strong anti-oxidative activity as compared with butylated hydroxyanisole and α-tocopherol. In addition, that activity is retained during ensiling for 4 weeks. These results suggest that the entire yacon plant can be used effectively as a feedstuff resource with the added bonus of anti-oxidant activity.

To resolve the discrepancy among previous karyotype descriptions, chromosome comparative study between two closely related cucumber cultivars, C. sativus L. cv. Borszczagowski and cv. Monastyrski, was performed by chromosome preparation technique with enzymatic maceration, and fluorescent banding method with chromomycin A3 (CMA) and 4′,6-diamidino-2-phenylindole (DAPI). Heterochromatic band polymorphisms were detected in chromosomes 2, 3, 5 and 7, whereas no chromosomal polymorphism was found in chromosomes 1, 4 and 6. In cv. Borszczagowski chromosome 2, CMA+DAPI+ heterochromatic band at terminal region of the long arm was smaller than that of cv. Monastyrski. Chromosome 3 of cv. Monastyrski was characterized by CMA+DAPI+ bands on the terminal regions of both arms, whereas that of cv. Borszczagowski displayed only on the terminal region of long arm. Distinct CMA+DAPI+ band located at terminal region of the long arm in cv. Borszczagowski was larger than that of cv. Monastyrski. In chromosome 7, terminal CMA+DAPI+ band at the short arm was only observed in cv. Monastyrski. This result suggested that inconsistency of karyotypes among previous reports was due to chromosomal polymorphism.

Yacon (Smallanthus sonchifolius), a native Andean plant, has been cultivated as a crop and locally used as a traditional folk medicine for the people suffering from diabetes and digestive/renal disorders. However, the medicinal properties of this plant and its processed foods have not been completely established. This study investigates the potent antioxidative effects of herbal tea leaves from yacon in different free radical models and a ferric reducing model. A hot-water extract exhibited the highest yield of total polyphenol and scavenging effect on 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical among four extracts prepared with hot water, methanol, ethanol, and ethylacetate. In addition, a higher reducing power of the hot-water extract was similarly demonstrated among these extracts. Varying concentrations of the hot-water extract resulted in different scavenging activities in four synthetic free radical models: DPPH radical (EC50 28.1 μg/mL), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) cation radical (EC50 23.7 μg/mL), galvinoxyl radical (EC50 3.06 μg/mL), and chlorpromazine cation radical (EC50 475 μg/mL). The yacon tea-leaf extract further demonstrated superoxide anion (O2(-)) radical scavenging effects in the phenazine methosulfate-NADH-nitroblue tetrazolium (EC50 64.5 μg/mL) and xanthine oxidase assay systems (EC50 20.7 μg/mL). Subsequently, incubating human neutrophilic cells in the presence of the tea-leaf extract could suppress the cellular O2(-) radical generation (IC50 65.7 μg/mL) in a phorbol 12-myristate 13-acetate-activated cell model. These results support yacon tea leaves may be a good source of natural antioxidants for preventing O2(-) radical-mediated disorders.Yacon has been considered to be a potent alternative food source for patients who require a dietary cure in regional area, while the leaf part has been provided and consumed as an herbal tea in local markets. We demonstrated here potent antioxidative effects of the tea leaves from yacon in different free radical assays, reducing power assay, and cellular superoxide anion radical generation assay. Results support yacon tea leaves may be a good source of natural antioxidants for preventing O2(-) radical-mediated disorders.

Zoysiagrass displays good adaptability to its environment, and is utilized for golf courses and athletic fields. Immature inflorescences were obtained from 5 varieties of zoysiagrass, ‘Miyako’, ‘Misato’, ‘Meyer’, ‘Yamato’ and ‘B14’. However, regenerated plants were only obtained in ‘Miyako’. A relationship between the size of the inoculated inflorescences and the callus induction frequency was observed. A high frequency of callus formation was shown in earlier developmental stages shorter than 20 mm in the length of inflorescences in ‘Miyako’. Plant regeneration was observed efficiently when the compact calli, which were formed in the callus induction medium (Linsmaier and Skoog 4 mg l−1 thiamine–HCl, 100 mg l−1 α-ketoglutaric acid, 2 mg l−1 2,4-D, 0.1 mg l−1 BA, 3% sucrose, 0.2% gelrite), were transferred to the regeneration medium (Linsmaier and Skoog 1 mg l−1 BA, 3% maltose, 0.5% gelrite ) in ‘Miyako’.

To determine the direct cause of the low seed set in sweet potato, 14 cross-compatible combinations among 11 varieties were histologically examined for the process from fertilization to embryogenesis at 4, 7 and 48 hours after pollination. Pollen fertility on the flowering day exceeded 80 % in most of the varieties examined and pollen germination 4 hours after pollination reached 10~20 % in most of the crosses. These results show that neither the fertility of mature pollen nor the pollen germination on stigma is the principal cause of the low seed set. The mean number of pollen tubes passing through the conducting tissue of the ovary 7 hours after pollination largely differed among the cross combinations. However, it did not show a close relationship with the number of seeds per capsule. Among the embryosacs examined 48 hours after pollination, those that had not been penetrated by pollen tubes were mostly abnormal, in which the development of the egg apparatus had been interrupted halfway. On the other hand, the number of normal young embryos was closely correlated with the number of seeds per capsule. These results suggest that a large number of such abnormal embryosacs is the principal cause of the low seed set of sweet potato.

Highly (100),(001)-oriented (Ba0.85Ca0.15)TiO3 (BCT) lead-free piezoelectricceramics were fabricated by the reactive templated grain growth method using a mixture of plate-like CaTiO3 and BaTiO3 particles. Piezoelectric properties of the ceramics with a high degree of texture were found to be considerably enhanced compared with the BCT ceramics with a low degree of texture. With increasing the Lotgering factor from 26% up to 94%, the piezoelectric properties develop towards the properties of a single crystal. The dynamics of polarization switching was studied over a broad time domain of 8 orders of magnitude and was found to strongly depend on the degree of orientation of the ceramics. Samples with a high degree of texture exhibited 2–3 orders of magnitude faster polarization switching, as compared with the ones with a low degree of texture. This was rationalized by means of the Inhomogeneous Field Mechanism model as a result of the narrower statistical distribution of the local electric field values in textured media, which promotes a more coherent switching process. The extracted microscopic parameters of switching revealed a decrease of the critical nucleus energy in systems with a high degree of texture providing more favorable switching conditions related to the enhanced ferroelectric properties of the textured material.

Mesophyll protoplasts of sweet potato, variety Chugoku No.25, were isolated from shoot tip cultures grown in vitro. After the surface of the leaves was scratched with sterilized carbo-rundum, they were plasmolyzed for I hour in 0.3 M sorbitol and 0.05 M CaCl2. The enzyme solution for isolation contained 0.1%Pectolyase Y-23, 2 % Cellulase Onozuka RS, 5 mM CaCl2 and 0.5 M mannitol in a modified K3 medium (Kao and Michayluk 1981). The crude protoplast suspension was filtered through a nylon mesh and protoplasts were isolated by discontinuous density gradient centrifugation. The initial medium used was a modified KM8p medium (Kao and Michayluk 1975) sup-plemented with 0.1 mg/l zeatin (ZEA), 0.1 mg/1 2, 4-dichlorophenoxyacetic acid (2, 4-D). 0.5 M mannitol and 10 g/l sucrose. The cell colonies formed were plated on a mQdified MS medium (Murashige and Skoog 1962) for callus forma-tion containing 20 g/l sucrose, 2 g/l Gellan Gum, 0.5 mg/l 2, 4-D and I mg/1 abscisic acid (ABA) with or without 0.5 mg/l kinetin (KlN) or 0.5 mg/l ZEA. Furthermore, the calli were transferred to a MS medium for regeneration supplemented with 30 g/l sucrose, 2 g/l Gellan Gum and 1 mg/l KlN or 0.5 mg/l ZEA. Compact calli were induced on the medium supplemented with ZEA, and regenerated plants were obtained. The effects of silver nitrate (AgNO3) and drying on plant regeneration were investigated. AgNO3 was not effective for plant regeneration, but the drying treatment for 3 days prior to transfer to the medium for regeneration was effective. Cell suspension protoplasts were isolated from the embryogenic calli initiated from the shoot apical domes in the same manner as used for mesophyll protoplast isolation. The initial culture medium and the callus proliferation medium were identical to those used for mesophyll protoplast. Drying treatuent was also effective to enhance the frequency of adventitious bud formation, and regenerated plants were obtained.

Protoplasts were isolated from young petioles of sweet potato (var. Chugoku No. 25). The enzyme solution for maceration contained 0.1% Pectolyase Y-23, 2% Cellulase Onozuka RS, 5mM CaCl2H2O and 0.5M mannitol. The crude protoplast suspension was filtered through a Miracloth and protoplasts were isolated by discontinuous density gradient centrifugation. As the initial plating medium for cell division, modified MURASHIGE and SKOOG (MS) medium was used. It contained 0.1mg/l kinetin (KIN), 0.1mg/l 2, 4-dichlorophenoxyacetic acid (2, 4-D). 0.5 M mannitol and 10g/l sucrose with modifled concentrations of NH4N03 and KN08. After one month, these media were replaced with new ones with a concentration of mannitol reduced to 0.25 M. Further, after one more month, these media were replaced to those without any mannitol. The most eflicient colony formation from protoplasts occurred on a medium containing 200mg/l NH4NO3 and 1, 000mg/l KN03, After about three months, the cell colonies were transferred to agar plates of modified MS media (800mg/l NH4NO3, 1, 400mg/l KNO3) supplemented with 20g/l sucrose 6g/l agar and various combinations of growth regulators (2, 4-D, KIN, abscisic acid (ABA)). Callus formation occurred more efficiently on media containing KIN.T than on media without KIN. Furthermore, the presence of ABA did not inhibit callus growth. The micro-calli were then transferred individually to MS media supplemented with 30g/l sucrose, 8g/l agar, and various concentrations of KIN and BA for regeneration. Shoot formation was induded only from the callus on a medium supplemented with 1.0mg/l KIN, and only when preceded by the culture on a medium containing 0.5mg/l 2, 4-D, 1.0mg/l ABA and 0.5mg/l KIN.

In order to get information of low seed set generally observed in sweet potato breeding, first of all, some observations on the normal process of fertilization and embryogenesis were made on the specimens collected at different intervals after pollinations from the compatible cross combination (Chikei 682-ll×Kyushu No.58). Approximately 4 hours after pollination, the pollen tube enters into one of the synergids through the micropyle. From 6 to 9 hours after pollination the double fertilizations occur, bringing forth the zygote and the endosperm nucleus. 14 and 10 hours after pollination both the former and the latter begin to show their first mitotic divisions, respectively. Approximately 24 hours after pollination, the zygote is to be differentiated into an apical cell and basal one, and the several endosperm nuclei begin to lie in the peripheral layer of the embryo-sac. 48 hours after pollination, the zygote is to be developed. into the embryo and the suspensor consisting of 8 cells, with the endosperm nuclei lying densely in the peripheral layer of the embryo-sac. 3 to 7 days after pollination, the zygote is to be differentiated into the embryo ball and the suspensor, and the formation of the cell walls surrounding respective endosperm nuclei begins from the micropyle side towards the antipodal one. 10 days after pollination, the zygote reachs heart stage, and the endosperm cells begin to be degenerated at the micropyle side. 13 to 17 days after pollination, a rapid elongation comes to be shown by the cotyledon, with the endosperm cells almost degen-erated.