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Background: Centipedegrass extract (CGE) is rich in several polyphenolic compounds including C-glycosylflavonoids, such as maysin and its derivatives, and exerts antioxidant, anti-adipogenic and anticancer effects. However, the effect of CGE on the immune system is unclear.Purpose: CGE might inhibit NO production induced by lipopolysaccharide (LPS). In this study, we propose a molecular mechanism for regulation of aberrant immune responses by CGE in LPS-stimulated RAW264.7 cells.Study Design: We will preparation of Centipedegrass extract and purify partially in rich of maysin and its derivatives. And examine the effect of the CGE on immune system using LPS-induced RAW cells and animals.Methods: LPS-induced nitric oxide (NO) and interleukin-6 levels were measured by enzyme-linked immunosorbent assay. The mRNA and protein levels of immune mediators were analyzed by reverse-transcription polymerase chain reaction and immunoblotting, respectively.Results: CGE inhibited LPS-induced NO production in a concentration-dependent manner by suppressing inducible nitric oxide synthase (iNOS) expression in LPS-stimulated cells; this effect was mediated by inhibition of the JAK/STAT pathway. However, CGE did not regulate the expression of other factors, including phosphorylated p38, c-jun N-terminal kinase, or extracellular signal-regulated kinase 1/2. In addition, CGE increased T cells percentage in peripheral blood after oral administration.Conclusion: These results indicate that CGE suppresses LPS-induced production of NO and expression of iNOS by directly inhibiting JAK2 kinase activity and enhancing effects on the immune system in mice. [ABSTRACT FROM AUTHOR]

The application of electron ionizing energy for degrading veterinary antibiotic ciprofloxacin (CFX) in aqueous solution was elucidated. The degradation efficiency of CFX after irradiation with electron ionizing energy was 38% at 1 kGy, 80% at 5 kGy, and 97% at 10 kGy. Total organic carbon of CFX in aqueous solution after irradiation with electron ionizing energy decreased 2% at 1 kGy, 18% at 5 kGy, and 53% at 10 kGy. The CFX degradation products after irradiation with electron ionizing energy were CFX1 ([M + H] m/z 330), CFX2 ([M + H] m/z 314), and CFX3 ([M + H] m/z 263). CFX1 had an F atom substituted with OH and CFX2 was expected to originate from CFX via loss of F or H 2 O. CFX3 was expected to originate from CFX via loss of the piperazynilic ring. Among the several radicals, hydrate electron ( e aq - ) is expected to play an important role in degradation of veterinary antibiotic during irradiation with electron ionizing energy. The toxicity of the degraded products formed during irradiation with electron ionizing energy was evaluated using microbes such as Escherichia coli, Pseudomonas putida , and Bacillus subtilis , and the results revealed that the toxicity decreased with irradiation. These results demonstrate that irradiation technology using electron ionizing energy is an effective was to remove veterinary antibiotics from an aquatic ecosystem. [ABSTRACT FROM AUTHOR]

Abstract: Radiolytic transformation of the isoflavonoid rotenone (1) with γ-irradiation afforded two new degraded products, rotenoisins A (2) and (3). The structures of the two new rotenone derivatives were elucidated on the basis of spectroscopic methods. The new products 2 and 3 exhibited significantly enhanced inhibitory activities against pancreatic lipase and adipocyte differentiation in 3T3-L1 cells when compared to parent rotenone. [Copyright &y& Elsevier]

Abstract: Pretreatment of poplar bark with a combination of sulfuric acid (3%, w/w, H2SO4) and gamma irradiation (0–1000kGy) was performed in an attempt to enhance enzymatic hydrolysis for bioethanol production. The yields of reducing sugar were slightly increased with an increasing irradiation dose, ranging from 35.4% to 51.5%, with a 56.1% reducing sugar yield observed after dilute acid pretreatment. These results clearly showed that soluble sugars were released faster and to a greater extent in dilute acid-pretreated poplar bark than in gamma irradiation-pretreated bark. When combined pretreatment was carried out, a drastic increase in reducing sugar yield (83.1%) was found compared with individual pretreatment, indicating the possibility of increasing the convertibility of poplar bark following combined pretreatment. These findings are likely associated with cellulose crystallinity, lignin modification, and removal of hemicelluloses. [Copyright &y& Elsevier]

Abstract: The objective of this study was to find a pretreatment process that enhances enzymatic conversion of biomass to sugars. Rapeseed straw was pretreated by two processes: a wet process involving wet milling plus a popping treatment, and a dry process involving popping plus dry milling. The effects of the pretreatments were studied both in terms of structural and compositional changes and change in susceptibility to enzymatic hydrolysis. After application of the wet and dry processes, the amounts of cellulose and xylose in the straw were 37–38% and 14–15%, respectively, compared to 31% and 12% in untreated counterparts. In enzymatic hydrolysis performance, the wet process presented the best glucose yield, with a 93.1% conversion, while the dry process yielded 69.6%, and the un-pretreated process yielded <20%. Electron microscopic studies of the straw also showed a relative increase in susceptibility to enzymatic hydrolysis with pretreatment. [Copyright &y& Elsevier]

Abstract: This review discusses the morphological changes and biological responses of plants irradiated with gamma rays. Seedlings exposed to relatively low doses of gamma rays (1–5Gy) developed normally, while the growth of plants irradiated with a high dose gamma ray (50Gy) was significantly inhibited. Based on TEM observations, chloroplasts were extremely sensitive to gamma irradiation compared to other cell organelles, particularly thylakoids being heavily swollen. In addition, some portions of the mitochondria and endoplasmic reticulum were structurally altered, for example, distortion and swelling. The cerium perhydroxide deposition, as a maker for H2O2 deposition, was typically manifest on the plasma membranes and cell walls of the tissues from both the control and irradiated plants. However, the intensities of cerium perhydroxide deposits (CPDs) were remarkably increased in the plasma membranes and cell walls of pumpkin tissues such as petiole, cotyledon, hypocotyl and especially leaf after gamma irradiation. These observations are in good agreement with the results of H2O2 content in all tissues. The immuno-localization analysis for peroxidase (POD) on the tissues from pumpkin plant showed the same pattern between the control and irradiated plants, but the density of gold particles as indication of POD localization was significantly increased on the cell corner middle lamellae of parenchyma cells, especially in the petiole after gamma irradiation. However, accumulation and localization of H2O2 and POD in vessels were not significantly different between both plants. The accumulation and localization of both H2O2 and POD were differentially affected by gamma irradiation depending on the different tissue types. The deposition of both H2O2 and POD in parenchyma cells appeared much higher than in vessels, suggesting that the former is more sensitive than the latter against gamma rays. [Copyright &y& Elsevier]

Abstract: This study was carried out to evaluate the efficiency of degradation of antibiotic ampicillin in pig manure slurry and an aqueous ampicillin solution with the use of electron beam irradiation as a function of the absorbed dose. The degradation efficiency of ampicillin was close to 95% at an absorbed dose of 10kGy. The degradation of ampicillin followed a “first-order” reaction rate with respect to absorbed dose. The results demonstrate that the electron beam irradiation technology is an effective means to remove antibiotics in manure and bodies of water. [Copyright &y& Elsevier]

Abstract: Owing to homogeneous hollow tube shape and hydrophobicity of kapok fiber, the usages of this fiber are various such as fiberfill in pillows, quilts, non-woven fabric for oil spill cleanup and plastic green house. Even though kapok fiber is able to apply various industrial usages, it has a serious disadvantage which is the extreme sensitivity to spark or flame. Therefore, we try to make flame-resistant kapok fiber using gamma ray. The radiation caused loss of hydrophobic compounds in kapok fiber and no morphological change, especially fine hollow tube shape, was observed. The lignin contents were negligible changed after gamma irradiation. However, the building units of lignin polymer such as coniferyl alcohol, and sinapyl alcohol were significantly changed that is, functional group as a methoxyl group from lignin polymer was cleaved by gamma irradiation. Based on the results of removal of hydrophobic compounds and cleavage of methoxyl group from lignin polymer, kapok fiber can be converted into a flame-resistant fiber by gamma ray treatment. [Copyright &y& Elsevier]

Abstract: Application of chemical probes, for detection of reactive oxygen species (ROS), was tested during γ-irradiation. The ethanol/α-(4-pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN) and 3,3′-diaminobenzidine (DAB) were structurally stable enough to detect OH and H2O2, increasingly generated by γ-irradiation up to 1000Gy. Interestingly, the production rate of H2O2, but not OH, during γ-irradiation, was significantly different between in vitro systems of lettuce and spinach. These results suggest that 4-POBN and DAB could be utilized as a semi-quantitative probe to quantify OH and H2O2, produced by γ-irradiation up to 1000Gy. [Copyright &y& Elsevier]

Alkaline nitrobenzene oxidation, ozonation and methoxyl content determinations were applied to decomposing leaf litter of Ginkgo biloba L., Cinnamomum camphora sieb., Zelkova serrata Makino and Firmiana simplex W. F. Wight, respectively, during mulching to investigate the properties and estimate changes in lignin composition and content . Since the Klason lignin residue originated from components highly resistant to degradation by acid, the methoxyl content of Klason residue was used to estimate the lignin content of leaf litter. Quantitative analysis of presumed lignin-derived fragments, by use of alkaline nitrobenzene oxidation and ozonation methods, suggested that the estimated lignin content approximates that of the real lignin content of leaves, which is greatly overestimated by the Klason procedure. The estimated lignin contents ranged from 3.9 to 10.0% while the Klason lignan residue varied from 37.1 to 46.7% in un-mulched leaf litter. The absolute amounts of the measured lignin somewhat decreased during mulching, while the structure of lignin remaining in leaf litters after mulching was considered not to be very different from its original structure. [Copyright &y& Elsevier]

[Display omitted] Baicalin, a glucuronic flavone, is the major active component in the medicinal plant Scutellaria baicalensis. Herein, baicalin was irradiated by γ-rays to afford four unusual flavanones, baicalinols A (2), B (3), and C (4) and peroxybaicaleinol (5), and two known flavones, oroxylin A (6) and baicalein (7). The structures of the hydroxymethylated products were elucidated using nuclear magnetic resonance spectroscopy and mass spectrometry, and their absolute configuration was established using electronic circular dichroism spectroscopy. Novel hydroxymethylated flavanones 2 and 3 suppressed both nitric oxide (NO) production and the expression of inducible NO synthase and showed significantly higher anti-inflammatory activities in lipopolysaccharide-stimulated macrophages than the parent compound. These newly generated hydroxymethylated flavanones can be potentially used for treating inflammatory diseases. [ABSTRACT FROM AUTHOR]

Eremochloa ophiuroides , a perennial warm-season lawn grass, has a characteristic phenotype of red pigmentation in tissues during maturation. The putative gene families associated with the red coloration were previously identified in E. ophiuroides. These genes encode chalcone synthases, flavonol 3-hydroxylases, and flavonol 3′-hydroxylases, acting on the early flavonoid-biosynthesis pathway. Here, a type-I chalcone isomerase (CHI) gene was isolated from E. ophiuroides based on leaf-transcriptome data, and the corresponding enzyme was functionally characterized in vitro and in planta. Complementation of Arabidopsis tt5 mutants by overexpressing Eo CHI recapitulated the wild-type seed coat color. Wounding and methyl jasmonate treatments significantly elevated the transcript level of EoCHI and total anthocyanin content in shoots. Confocal microscopy indicated the localization of Eo CHI to the endoplasmic reticulum. The genomic EoCHI sequence contained two introns with a novel pattern of exon‒intron organization. Further examinations on genomic structures of CHI family from ancient to advanced plant lineages should be of interests to decipher evolutionary pathways of extant plant CHI genes. • A chalcone isomerase in E. ophiuroides was predicted by RNA-sequencing analysis. • A cDNA encoding a type-I Eo CHI was isolated and functionally characterized. • An Arabidopsis tt5 mutant was complemented with Eo CHI. • Wound and MeJA treatment induced accumulation of EoCHI transcripts and anthocyanin contents. • We identified "intron 2 loss" as a novel genomic organization in the EoCHI gene. [ABSTRACT FROM AUTHOR]

Centipedegrass (Eremochloa ophiuroides [Munro] Hack.) is a warm-season turfgrass, widely planted in residential lawns and recreational fields. Here, we uncovered three major terpenes released from the shoots of Eo : (E)-β-ocimene (6%), α-muurolene (87.8%), and eremophilene (6.2%). Methyl jasmonate (MeJA) treatment increased the emission of monoterpenes, including (E)- and (Z)-β-ocimene, limonene, and myrcene, as well as sesquiterpene blends of (E)-caryophyllene, α-copaene, (+)-cyclosativene, and α-farnesene. RNA sequencing analysis predicted 14 putative Eo terpene synthase (EoTPS) genes, and two full-length EoTPS were successfully amplified: Eo7816 (1722 bp) and Eo6039 (1701 bp). Phylogenetic analysis revealed that Eo7816 and Eo6039 belonged to the clades of TPS-b and TPS-a, respectively. The Arabidopsis transgenic plants overexpressing Eo7816 exclusively released (E)-β-ocimene (96%) with (Z)-β-ocimene and myrcene. In contrast, Eo6039 -overexpressing Arabidopsis plants emitted significant amounts of α-muurolene (69.4%) and eremophilene (21.8%). Together, we demonstrated that the two TPSs play roles in producing major volatile terpenes in Eo. • Volatile terpenes emitted from Eremochloa ophiuroides aerial tissues were measured. • MeJA treatment induced the release of (E)-caryophyllene as a major compound. • Fourteen putative terpene synthase genes were predicted by RNA sequencing analysis. • A MeJA-inducible (E)-β-ocimene synthase was identified and characterized. • We identified and characterized the first α-muurolene synthase from a plant species. [ABSTRACT FROM AUTHOR]

Highlights • Update on DNA damage response (DDR) signaling pathways in plants. • Recent advances in cellular and phenotypic DDRs, especially induced by IR. • Epigenetic regulation of DDRs associated with genome instability in plants. • Genotoxic agents and their DDRs in plants. Abstract Plants orchestrate various DNA damage responses (DDRs) to overcome the deleterious impacts of genotoxic agents on genetic materials. Ionizing radiation (IR) is widely used as a potent genotoxic agent in plant DDR research as well as plant breeding and quarantine services for commercial uses. This review aimed to highlight the recent advances in cellular and phenotypic DDRs, especially those induced by IR. Various physicochemical genotoxic agents damage DNA directly or indirectly by inhibiting DNA replication. Among them, IR-induced DDRs are considerably more complicated. Many aspects of such DDRs and their initial transcriptomes are closely related to oxidative stress response. Although many key components of DDR signaling have been characterized in plants, DDRs in plant cells are not understood in detail to allow comparison with those in yeast and mammalian cells. Recent studies have revealed plant DDR signaling pathways including the key regulator SOG1. The SOG1 and its upstream key components ATM and ATR could be functionally characterized by analyzing their knockout DDR phenotypes after exposure to IR. Considering the potent genotoxicity of IR and its various DDR phenotypes, IR-induced DDR studies should help to establish an integrated model for plant DDR signaling pathways by revealing the unknown key components of various DDRs in plants. [ABSTRACT FROM AUTHOR]

Radiation is a promising technique for improving the safety and shelf-life of processed foods. In the present investigation, the degradation mechanism and bioactivity improvement of rosmarinic acid (RA) were studied in response to various gamma irradiation doses (10, 20, and 50 kGy). RA exposed to gamma irradiation at 50 kGy was completely degraded and showed an increased inhibitory effect against 3 T3-L1 preadipocyte compare to the parent compound. Structures of the newly generated compounds 2 – 4 from irradiated RA at 50 kGy were elucidated based on spectroscopic methods, including 1 H nuclear magnetic resonance (NMR) and mass spectrometry (MS). Interestingly, compounds 2 and 5 exhibited significantly enhanced anti-adipogenic properties in 3 T3-L1 cells compared to the original compound. These results provide evidence that structural changes in RA induced by gamma irradiation might enhance biological efficacy. [ABSTRACT FROM AUTHOR]

Highlights: [•] Cya-3-rut in methanol was degraded by gamma irradiation in a dose-dependent manner. [•] A new phenolic compound from cya-3-rut was generated by gamma irradiation. [•] A new phenolic compound, protocatechuic acid methyl ester, was identified. [•] A degradation mechanism of cya-3-rut methanol extracts by radiolysis was proposed. [ABSTRACT FROM AUTHOR]

Abstract: Extracts from centipedegrass (Eremochloa ophiuroides Munro) have been previously identified as having beneficial effects medically and cosmetically. In this study, the effects of gamma irradiation on pigment removal and biological activities of centipedegrass extracts to promote industrial application were investigated. The methanolic extracts were exposed to gamma irradiation at dose ranging from 2 to 20kGy. The major pigments of centipedegrass extracts, cyanidin-3-O-glucoside and cyanidin-3-O-(6″-malonyl-)glucoside, were found to be effectively removed by gamma irradiation above 10kGy. Although the reddish-orange color of the cyanidins was markedly decreased by gamma irradiation, the biological activities were relatively unaffected. The biological activities such as 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity, inhibition of tyrosinase activity, and inhibition of elastase activity in methanolic extracts were modulated from 50.5% to 70.2%, from 50.9% to 65.8% and from 65.6% to 94.0%, respectively. Surprisingly, the biological activities have the highest activities after 6–8kGy of gamma irradiation. These results indicate that despite pigment degradation, biological activities were maintained or increased by gamma irradiation. Based on these results, gamma irradiation may be a useful tool to remove the undesirable reddish-orange color present in centipedegrass without any loss of biological activities, thereby promoting its utility in industrial applications such as manufacturing of cosmetic products. [Copyright &y& Elsevier]

Abstract: Salinization plays a primary role in soil degradation and reduced agricultural productivity. We observed that salt stress reversed photosynthesis and reactive oxygen scavenging responses in leaves or roots of two rice cultivars, a salt-tolerant cultivar Pokkali and a salt-sensitive cultivar IR-29. Salt treatment (100 mM NaCl) on IR-29 decreased the maximum photochemical efficiency (Fv/Fm) and the photochemical quenching coefficient (qP), thereby inhibiting photosynthetic activity. By contrast, the salt treatment on Pokkali had the converse effect on Fv/Fm and qP, while increasing the nonphotochemical quenching coefficient (NPQ), thereby favoring photosynthetic activity. Notably, chloroplast or root cells in Pokkali maintained their ultrastructures largely intact under the salt stress, but, IR-29 showed severe disintegration of existing grana stacks, increase of plastoglobuli, and swelling of thylakoidal membranes in addition to collapsed vascular region in adventitious roots. Pokkali is known to have higher hydrogen peroxide (H2O2)-scavenging enzyme activities in non-treated seedlings, including ascorbate peroxidase, catalase, and peroxidase activities. However, these enzymatic activities were induced to a greater extent in IR-29 by the salt stress. While the level of endogenous H2O2 was lower in Pokkali than in IR-29, it was reversed upon the salt treatment. Nevertheless, the decreased amount of H2O2 in IR-29 upon the salt stress didn't result in a high scavenging activity of total cell extracts for H2O2, as well as O2 − and OH species. The present study suggests that the tolerance to the moderate salinity in Pokkali derives largely from the constitutively maintained antioxidant enzymatic activities as well as the induced antioxidant enzyme system. [Copyright &y& Elsevier]

Abstract: Studies focused on the responses of plants to ionizing radiation are becoming more important due to the increased need for radiation-induced mutations, post-harvest or phytosanitary irradiation treatment of plants, and environmental monitoring of radioactive sites. To elucidate the influence of ionizing radiation on genome-wide transcription in plants, we performed integrated analysis of diverse transcriptomic data from different Arabidopsis samples and at various time points after γ irradiation or H2O2 treatment. The expression levels of most of the differentially expressed genes (DEGs) that were induced or repressed after γ irradiation returned to baseline levels of transcription within 12h, while some of these genes showed prolonged transcriptional changes. Expression of the DEGs did not correlate with genomic DNA methylation; however, there were substantial differences in DEG levels between the wild type and the cmt3-11 mutant, which has a defect in non-CG DNA methylation. Moreover, the proportion of the DEGs in common between 2 independent experiments using different batches of samples was only 12–18%. These results suggest that there is a diversity or randomness in radiation-induced physiological or phenotypic alterations. However, the results also indicated that 47 DEGs maintained a transcriptional change until 48h, and 7 of them, until 16d. Forty-five additional DEGs were found to be sustainably induced or repressed until 24h after γ irradiation regardless of sample-to-sample variation or genotype, and 4 or 2 of them, until 5d or 16d, respectively. Therefore, we suggest that the 4 γ-ray-responsive genes that showed sustainable transcriptional changes until day 5 would be reliable and reproducible genetic markers when evaluating the responsiveness of plants to γ-rays. [Copyright &y& Elsevier]

Abstract: In the present study, Schisandra chinensis (SC) was evaluated for inhibition effects on adipocyte differentiation in 3T3-L1 cells and anti-obesity properties in high fat diet (HFD)-induced obese rats. SC prevented lipid accumulation and impaired the differentiation of 3T3-L1 preadipocytes into adipocytes in a dose-dependent manner compared with the cells allowed to differentiate in DMII treated-control cells. SC treatment decreased expression of the key adipocyte differentiation regulator C/EBPβ, as well as C/EBPα or PPARγ, and resultant down-regulation of the terminal marker gene, aP2 during differentiation of 3T3-L1 preadipocytes into adipocytes. Moreover, Akt and GSK3β phosphorylation was down-regulated by SC treatment, which blocked adipogenesis and adipocyte differentiation. SC also inhibited HFD induced weight gain and adiposity in rats. HFD-induced obese rats showed a significant increase in the levels of serum TG and TC compared to rats on a normal diet. However, the levels of serum TG and TC in HFD+SC rats reduced significantly relative to the levels in HFD rats. Taken together, our results indicate that SC extracts inhibited preadipocyte differentiation and adipogenesis in cultured cells, leading to decreased body weight and fat tissue mass in HFD obese rats. [Copyright &y& Elsevier]

Abstract: Cyanidin-3-O-xylosylrutinoside (cya-3-O-xylrut), a major pigment in Schizandra chinensis Baillon, was effectively removed by gamma irradiation of greater than 2kGy, whereas quercetin, the most abundant of the flavonoids and has anti-inflammatory and anti-allergic effects, could be generated by degradation of cya-3-O-xylrut. In the present study, we investigated the effect of combination treatment of gamma irradiation and hydrogen peroxide (H2O2) on the formation of quercetin through the degradation of cya-3-O-xylrut. Cya-3-O-xylrut was significantly degraded (∼93%) by gamma irradiation at 2kGy and it was completely removed by a combination treatment (0.2% H2O2 and 2kGy gamma ray). The formation of quercetin was significantly appeared at 2kGy of gamma ray, together with disappearance of cya-3-O-xylrut. The quercetin formation by gamma ray is 3.2μg/ml and combination treatment is 7.7μg/ml. Therefore, the combination treatment of H2O2 and gamma ray is more effective to convert cya-3-O-xylrut into quercetin than gamma irradiation only. In conclusion, gamma ray combined with H2O2 would be a promising tool for bio-conversion of organic compounds. [Copyright &y& Elsevier]

Abstract: The ethanolic extracts of red beet (Beta vulgaris L.) hairy root were used to investigate the removal of color and improvement of biological activity for enhanced industrial applications. The extracts were exposed to gamma rays ranging from 2.5 to 30kGy. The red beet hairy root is composed of two major red-colorants, betanin and isobetanin. Gamma ray radiation at 5kGy remarkably reduced the levels of the major colorants by 94% and the reddish color was eliminated by doses greater than 10kGy. Color removal was likely due to the gamma ray radiolysis of ethanol. Although details on the mechanism responsible for the decay of the chromophore have not been entirely determined, our results suggest that the free radicals that are produced during this process are capable of destroying the chromophore group in isobetanin, thus bleaching the substrate solution. In spite of the degradation of the major colorants, the biological activities of constituents of the extract such as DPPH radical scavenging and tyrosinase inhibition were negligibly affected by the gamma ray radiation up to 20kGy. The antioxidant activity was 92.7% in control samples and 90.0–92.0% in irradiated samples (2.5–20kGy), and a slight decrease to 87.5% was observed for gamma ray radiation at 30kGy. In addition, tyrosinase inhibition activity has also the same pattern; the activity is slightly increased from 50.7% of control to 49.1–52.8% of irradiated samples (2.5–20kGy) with a 46.8% at 30kGy. [Copyright &y& Elsevier]

Abstract: PP1084 protein was exposed to gamma irradiation ranging from 5 to 500kGy. Native PAGE showed minor structural changes in PP1084 at 5kGy, and major structural changes at >15kGy. Size-exclusion chromatography (SEC) showed the formation of a new shoulder peak when the protein was irradiated with 15 and 30kGy, and a double peak appeared at 100kGy. The results of PAGE and SEC imply that PP1084 protein is degraded by gamma irradiation, with simultaneous oligomerization. PP1084 chaperone activity reached the highest level at 30kGy of gamma irradiation, and then, decreased in a dose-dependent manner with increasing gamma irradiation. However, the peroxidase activity significantly decreased following exposure to all intensities of gamma irradiation. The improvement of chaperone activity using gamma irradiation might be promoted by the oligomeric structures containing covalently cross-linked amino acids. Consequently, PP1084 modification using gamma irradiation could elevate chaperone activity by about 3–4 folds compared to the non-irradiated protein. [Copyright &y& Elsevier]

Abstract: The red leaves of centipedegrass are known to produce compounds with stronger antibiotic effects than those produced by green leaves. Therefore, the aim of this study was to identify if stress methods (e.g., gamma irradiation, UV-B irradiation, and wounding) could effectively convert green leaves to red leaves, and thereby increase the production of maysin and maysin derivatives that have been known for antibiotic properties. Our results showed differential concentration changes for different compounds using these stress methods. The concentrations of luteolin increased from 0.014% to 0.019%, 0.022%, and 0.028% following gamma irradiation, UV-B irradiation, and wounding, respectively. The concentration of isoorientin increased from 0.898% to 1.938% and 2.538%, while the concentration of mixed rhamnosylisoorientin and orientin increased from 0.303% to 0.474% and 0.690%, following UV-B irradiation and wounding, respectively. Gamma irradiation produced concentrations of isoorientin, rhamnosylisoorientin, and orientin similar to those found in red leaves. The concentrations of derhamnosylmaysin increased from 0.004% to 0.009%, 0.015%, and 0.024% by gamma irradiation, UV-B irradiation, and wounding, respectively. The concentration of maysin increased from 0.515% to 0.714%, 0.583%, and 0.777% by gamma irradiation, UV-B irradiation, and wounding, respectively, while the concentration of luteolin-6-C-boivinopyranoside increased from 0.324% to 0.834%, 0.979%, and 1.493% by gamma irradiation, UV-B irradiation, and wounding, respectively. According to these results, wounding and gamma irradiation are promising methods for increasing the concentrations of maysin and maysin derivatives. [Copyright &y& Elsevier]

Abstract: The effect of gamma irradiation on the content of total phenolic compounds, especially quercetin (Q), in onion (Allium cepa L.) skin was investigated. Onion skin extracts contained two predominant flavonoid compounds, Q and quercetin-4′-glucoside (Q4′G). After 10kGy gamma irradiation, the yield of Q in the extracts increased significantly from 36.8 to 153.9μg/ml of the extract, and the Q4′G content decreased slightly from 165.0 to 134.1μg/ml. In addition, the total phenolic compound content also increased after irradiation at 10kGy, from 228.0μg/g of fresh weight to 346.6μg/g; negligible changes (237.1–256.7μg/g) occurred at doses of up to 5kGy. As we expected, radical-scavenging activity was enhanced remarkably (by 88.8%) in the 10kGy irradiated sample. A dose-dependent increase in the peak intensity of the electron paramagnetic resonance (EPR) spectra was observed in all irradiated samples, with a maximum increase at 10kGy. The intensity relative to that of the control was 0.15, and it increased to 1.10 in 10kGy irradiated samples. The optimum gamma irradiation dose, which is sufficient to break the chemical or physical bonds and release soluble phenols of low molecular weight in onion skin, is about 10kGy. [Copyright &y& Elsevier]

Abstract: The peroxiredoxin protein expressed in Pseudomonas aeruginosa PAO1 (PaPrx) is a typical 2-cysteine peroxiredoxin that has dual functions as both a thioredoxin-dependent peroxidase and molecular chaperone. As the function of PaPrx is regulated by its structural status, in the present study, we examined the effects of electron beam radiation on the structural modifications of PaPrx, as well as changes to PaPrx peroxidase and chaperone functions. It was found that the chaperone activity of PaPrx was increased approximately 3- to 4-fold at 2kGy when compared to non-irradiated PaPrx, while its peroxidase activity decreased. This corresponded to a shift from the low molecular weight PaPrx species that acts as a peroxidase to the high molecular weight complex that functions as a chaperone, as detected using polyacrylamide gel electrophoresis. We also investigated the influence of the electron beam on physical protein properties such as hydrophobicity and secondary structure. The exposure of the PaPrx hydrophobic domains in response to irradiation reached a peak at 2kGy and then decreased in a dose-dependent manner at higher doses. In addition, the exposure of β-sheet and random coil elements on the surface of PaPrx was significantly increased following irradiation with an electron beam, whereas exposure of α-helix and turn elements was decreased. These results suggest that irradiated PaPrx may be a potential candidate for use in bio-engineering systems and various industrial applications, due to its enhanced chaperone activity. [Copyright &y& Elsevier]

Abstract: The fruit of Schizandra chinensis Baillon is a well-known traditional medicinal plant in Korea, China and Japan. We examined the effects of gamma irradiation on decolourisation and biological activity of S. chinensis fruit extracts to facilitate industrial applications. Samples were exposed to gamma-ray irradiation from 0.5 to 10kGy. Irradiation of greater than 2kGy markedly reduced the major colourant in S. chinensis fruit extracts, cyanidin-3-O-xylosylrutinoside (Cya-3-O-xylrut), by 80–90%. Biological activities, such as radical-scavenging activity and elastase inhibition activity, were not affected by gamma irradiation, but we observed a 12.3% increase in tyrosinase inhibition activity. There were negligible changes in the amounts of the major lignans schizandrin, gomisin A and gomisin N, following irradiation. These results indicated that gamma irradiation can selectively remove undesirable colour in S. chinensis extracts without adverse changes in biological activity. [ABSTRACT FROM AUTHOR]

Abstract: Ionizing radiation is a potent mutagen and has been used to induce random mutagenesis in plants for plant breeding. For the first time, it was revealed that γ irradiation of plants at the early reproductive stage could induce specific alterations in gene expressions involving in pigment metabolism and thereby delay the developmental leaf senescence at the later senescing stage. One-month-old Arabidopsis plants exposed to γ rays at a dose of 50Gyh−1 for 4h maintained much higher contents of chlorophylls, carotenoids, proteins, and anthocyanins in leaves at the late reproductive (senescing) stage compared with the control. Interestingly, expression levels of AtPAO and AtSAG12, which are inducible by developmental leaf senescence, were significantly lower in the irradiated leaves than in the control ones, while transcription of AtHEMA1, AtPORB, AtPORC, AtCHLG, and AtANS involving in chlorophyll and anthocyanin anabolism was noticeably increased in the former. Ultrastructure analysis of chloroplasts and thylakoid membranes indicated much less disintegration in the irradiated leaves, whilst most thylakoid membrane proteins for photosynthesis subjected to blue-native gel and immunoblot analysis, seemed to be relatively less affected after γ irradiation. Moreover, the maximal photosynthetic electron transport rate, ETRmax, was steeply decreased in the control leaves during the developmental leaf senescence, but maintained relatively constant in the irradiated ones. The delay in leaf senescence of the irradiated leaves was also confirmed by the additional dark-incubation for 5d. These results strongly suggest specific radiation-induced disturbances in pigment metabolism and photosynthesis to correlate with delay in leaf senescence of plants at the reproductive stage. [Copyright &y& Elsevier]

Abstract: Organic compost is a useful fertilizer for organic farming. However, it poses a microbiological hazard to the farm products because most of the composts are originated from excremental matters of domestic animals. In this study, the radiation treatment was performed to improve microbiological safety of organic compost and the effectiveness of gamma irradiation for inactivating Salmonella Typhimurium and Escherichia coli was investigated. The total aerobic and coliform bacteria in the 16 commercial composts were ranged from 105 to 107 CFU/ml and 0 to 103 CFU/ml, respectively. All coliform bacteria in the composts were eliminated by irradiation at a dose of 3kGy, while about 102 CFU/ml of the total aerobic bacteria were survived up to 10kGy. In the artificial inoculation test, the test organisms (inoculated at 107 CFU/g) were eliminated by irradiation at 3kGy. Approximate D 10 values of Salmonella Typhimurium and E. coli in the compost were 0.40 and 0.25kGy, respectively. In the cultivation test, the test organisms of the compost had transfer a lettuce leaves. The growth pattern of lettuce was not different between irradiated and non-irradiated composts. [Copyright &y& Elsevier]