Antioxidative effect of CLA diet and endurance training in liver and skeletal muscles of rat

The purpose of this study is to investigate the effects of conjugated linoleic acid (CLA) supplementation and endurance exercise on the oxidative/anti-oxidative status in rat liver and skeletal muscles. Sprague-Dawley male rats were randomly divided into HS (high-fat diet sedentary group, n = 8), CS group (CLA supplemented sedentary group, n = 8), and CE group (CLA supplemented exercise group, n = 8). For CLA supplementation, 1.0% CLA was substituted for dietary fat. For endurance exercise, the rats swam for 60 min a day, 5 days a week for 8 weeks. The MDA content, Cu, Zn-SOD and Mn-SOD expression in the soleus muscle (SOM) of the CE group improved significantly compared to the HS (p < 0.01) and CS groups (p < 0.05). Moreover, Mn-SOD expression in both the SOM and extensor digitorum longus muscle (EDL) of the CS were enhanced significantly compared to the HS (p < 0.05). From these results, it was suggested that CLA supplementation under the endurance exercise condition may improve the oxidative status by decreasing the MDA content via potential scavenging of Cu,Zn-SOD, and Mn-SOD protein in red muscle, respectively. Therefore, our study demonstrated long-term endurance exercise with CLA supplementation plays a crucial role for maintenance of antioxidative properties in the skeletal muscle of rat.     

Engineering a highly thermostable and stress tolerant superoxide dismutase by N-terminal modification and metal incorporation

Thermophilic or hyperthermophilic SODs (superoxide dismutase) usually offer substantial biotechnological advantages over mesophilic SODs. Previously a 244-amino acid N-terminal domain (NTD) from a heatresistant SOD of Geobacillus thermodenitrificans NG80-2 was discovered and demonstrated to be able to confer thermostability to homologous mesophilic SODs, which revealed a new type of heat resistance mechanism. To further improve the heat resistance and stress tolerance of thermophilic cambialistic superoxide dismutase (Fe/Mn- SOD _Ap ) from Aeropyrum pernix K1 through metal incorporation and fusion with the newly found peptide NTD for broadening its industrial application, the wildtype SOD _Ap and NTD-fused ntdSOD _Ap were expressed in E. coli BL21 and incorporated with metal cofactors by two ways. Recombinant fusion SOD obtained by in vitro reconstitution (Mn-rec ntdSOD _Ap ) exhibited improved optimum temperature at 70°C and dramatically enhanced thermostability especially at 110°C with enhanced pH stability from 4 to 10 and higher tolerance for denaturants and organic media than Mn-rec SOD _Ap . To the best of our knowledge, Mn-rec ntdSOD _Ap could be the most heat resistant SOD. In addition, metal incorporation of SOD _Ap and ntdSOD _Ap via in vivo modification have been developed and proved to be more practical for industrial use. These results indicate that fusion with NTD along with metal incorporation can generate superimposed effect and be applied to enhance the stability of cambialistic thermophilic SODs, thus providing a universal and convenient bioengineering method for generating extremely stable SODs.     

Acaricidal and repellent effects of <Emphasis Type="Italic">Cnidium officinale</Emphasis>-derived material against <Emphasis Type="Italic">Dermanyssus gallinae</Emphasis> (Acari: Dermanyssidae)

The acaricidal activity of a methanolic extract and fractions from the rhizome of Cnidium officinale against Dermanyssus gallinae adults was investigated. The C. officinale methanolic extract exhibited 100% acaricidal activity after 48 h of treatment at a dose of 4000 ppm. The acaricidal constituents of the plant were sequentially partitioned with several solvents and then purified using silica gel column chromatography and high-performance liquid chromatography. Gas chromatography–mass spectrometry and nuclear magnetic resonance spectroscopy revealed (Z)-ligustilide as a constituent of C. officinale. Acaricidal activity was examined in three experimental tests (spray, fumigation and contact), with the spraying method being the most effective. The methanolic extract of C. officinale showed both contact and fumigant activities, though only fumigant activity was observed with (Z)-ligustilide. The fumigant effects of the methanolic extract and (Z)-ligustilide caused 86.5 and 62.6% mortality, respectively, of D. gallinae adults at 48 h. Among (Z)-ligustilide, acaricides (bifenthrin, cypermethrin and spinosad) and butylidenephthalide, bifenthrin displayed the highest acaricidal activity, and the activity of butylidenephthalide was 2.3-fold higher than that of (Z)-ligustilide. These results suggest that C. officinale-derived material can be used for the development of a control agent for D. gallinae.     

Examining olfactory and visual cues governing host-specificity of a weed biological control candidate species to refine pre-release risk assessment

In weed biological control programs, pre-release host-specificity testing relies traditionally on no-choice and choice feeding, oviposition, and development tests. Rarely have they included detailed examination of behavioral responses to olfactory and visual cues of biological control candidates, although a better understanding of the mechanisms underlying host recognition may explain potential discrepancies between choice and no-choice tests, and/or between tests conducted in the lab versus field conditions. We investigated how the seed-feeding weevil, Mogulones borraginis, distinguishes its host plant, Cynoglossum officinale, from three native confamilial non-target species in North America. In behavioral bioassays, M. borraginis responded to olfactory and visual cues individually and, to an even greater extent, to both plant cue modalities when offered simultaneously. In tests with the combined cues, M. borraginis was attracted to C. officinale but responded with indifference or was repelled by non-target plants. In electrophysiological experiments, we identified that M. borraginis responded to ten volatile compounds and four wavelengths of lights from inflorescences of C. officinale. We propose that studies of responses to multimodal plant cues can advance our understanding of how biocontrol candidate species discriminate among host plants and closely related non-target species, thereby increasing the accuracy of environmental safety assessments pre-release.     

Effects of soil moisture content on the growth and physiological status of ginger (<Emphasis Type="Italic">Zingiber officinale</Emphasis> Roscoe)

Ginger (Zingiber officinale Roscoe), one of the most valuable economic plants from the Zingiberaceae family, is used worldwide as a spice and flavoring agent in the beverage, bakery, confectionary, and pharmaceutical industries. Soil moisture is one of the most important constraints in ginger cultivation. In the present paper, the phenotype, physiology, biochemistry, and expression difference of genes coding for key enzyme for endogenous hormone metabolism in ginger under different soil moisture conditions (water-filled pore space, WFPS) were measured. Our results indicated that with the increase of soil moisture content, the ramet number of Z. officinale gradually increased, and the ramet number increased to 26.7?±?3.7 at 40% humidity. However, the stem height, stem diameter, and the relative chlorophyll content were highest at 25% humidity. Similarly, the activities of superoxide dismutase (SOD) and peroxidase (POD) as well as the contents of abscisic acid (ABA) and ethylene (Eth) content remained relatively low at 25% humidity, whereas they were relatively high at lower moisture (10%) and higher moisture (30–40%) levels. In addition, the expression patterns of key enzyme-coding genes involved in ABA synthesis and Eth metabolism were analyzed to elucidate the effect of soil moisture on ginger cultivation. The results showed that the expression of the genes were in accordance with the variation of ABA and Eth under different soil moisture levels. In sum, soil moisture significantly affects the growth of Z. officinale, and 25% soil humidity is suitable for the growth of Z. officinale.     

Identification,characterization, and expression of the <Emphasis Type="Italic">SWEET</Emphasis> gene family in <Emphasis Type="Italic">Phalaenopsis equestris</Emphasis> and <Emphasis Type="Italic">Dendrobium officinale</Emphasis>

Sugars are important molecules that function not only as primary metabolites, but also as nutrients and signal molecules in plants. The sugar transport protein genes family SWEET has been recently identified. The availability of the Dendrobium officinale and Phalaenopsis equestris genome sequences offered the opportunity to study the SWEET gene family in this two orchid species. We identified 22 and 16 putative SWEET genes, respectively, in the genomes of D. officinale and P. equestris using comprehensive bioinformatics analysis. Based on phylogenetic comparisons with SWEET proteins from Arabidopsis and rice, the DoSWEET and PeSWEET proteins could be divided into four clades; among these, clade II specifically lacked PeSWEETs and clade IV specifically lacked DoSWEETs, and there were orthologs present between D. officinale and P. equestris. Protein sequence alignments suggest that there is a predicted serine phosphorylation site in each of the highly conserved MtN3/saliva domain regions. Gene expression analysis in four tissues showed that three PeSWEET genes were most highly expressed in the flower, leaf, stem, and root, suggesting that these genes might play important roles in growth and development in P. equestris. Analysis of gene expression in different floral organs showed that five PeSWEET genes were highly expressed in the column (gynostemium), implying their possible involvement in reproductive development in this species. The expression patterns of seven PeSWEETs in response to different abiotic stresses showed that three genes were upregulated significantly in response to high temperature and two genes were differently expressed at low temperature. The results of this study lay the foundation for further functional analysis of SWEET genes in orchids.     

Hybridization rate and genotypic diversity of apomictic hybrids between native (<Emphasis Type="Italic">Taraxacum japonicum</Emphasis>) and introduced (<Emphasis Type="Italic">T. officinale</Emphasis>) dandelions in western Japan

Hybridization between the introduced and native plants may enhance invasiveness, especially in asexually reproducing species. Hybrid apomictic dandelions between native (Taraxacum platycarpum and T. japonicum) and exotic (T. officinale) species are distributed widely throughout Japan. To estimate the origin(s) and dispersal of the hybrids, we investigated the hybridization rate and genotypic diversity in mixed populations of T. japonicum, T. officinale and their hybrids at two green parks in western Japan. Among the plants identified as exotics from flower morphology, 86–96% were hybrids by genetic analysis. Genetic data with simple sequence repeat markers revealed a high clonal diversity of the hybrid both within and between populations, indicating multiple origins. A hybrid seed was found from among the 1891 seeds collected from T. japonicum in the parks, indicating ongoing hybridization in the field. T. officinale and hybrids were genetically differentiated between the two parks independent of the ploidy level; the allele frequency of T. officinale and tri- and tetraploid hybrids were similar within each park but different between the two parks. This suggests that the origins of hybrids were similar within the park but different between the parks. Overall, our results suggest that hybridization, including backcross, is an ongoing process, and that genetically diverse hybrids with various origins have been spreading in western Japan, probably because hybridization enhanced invasiveness at native habitat.     

A nodule endophytic plant growth-promoting <Emphasis Type="Italic">Pseudomonas</Emphasis> and its effects on growth,nodulation and metal uptake in <Emphasis Type="Italic">Medicago lupulina</Emphasis> under copper stress

The aim of this study was to determine the plant growth-promoting potential of the nodule endophytic Pseudomonas brassicacearum strain Zy-2-1 when used as a co-inoculant of Medicago lupulina with Sinorhizobium meliloti under copper (Cu) stress conditions. Strain Zy-2-1 was capable of producing ACC deaminase activity, IAA and siderophores, and was able to grow in the presence of Cu²⁺ up to 2.0 mmol/L. Co-inoculation of S. meliloti with Zy-2-1 enhanced M. lupulina root fresh weight, total plant dry weight, number of nodules, nodule fresh weight and nitrogen content in the presence of 100 or 300 mg/kg Cu²⁺. In the presence of 500 mg/kg Cu²⁺, co-inoculation with S. meliloti and strain Zy-2-1 increased plant height, number of nodules, nodule fresh weight and nitrogen content in comparison to S. meliloti inoculation alone. Furthermore, a higher amount of Cu accumulation in both shoots and roots and a higher level of Cu translocation to shoots were observed in co-inoculated plants. These results demonstrate that co-inoculation of M. lupulina with S. meliloti and P. brassicacearum Zy-2-1 improves plant growth, nitrogen nutrition and metal extraction potential. This can be of practical importance in the remediation of heavy metal-contaminated soils.     

Mining and characterization of EST-SSR markers for <Emphasis Type="Italic">Zingiber officinale</Emphasis> Roscoe with transferability to other species of Zingiberaceae

Zingiber officinale is a model spice herb, well known for its medicinal value. It is primarily a vegetatively propagated commercial crop. However, considerable diversity in its morphology, fiber content and chemoprofiles has been reported. The present study explores the utility of EST-derived markers in studying genetic diversity in different accessions of Z. officinale and their cross transferability within the Zingiberaceae family. A total of 38,115 ESTs sequences were assembled to generate 7850 contigs and 10,762 singletons. SSRs were searched in the unigenes and 515 SSR-containing ESTs were identified with a frequency of 1 SSR per 25.21 kb of the genome. These ESTs were also annotated using BLAST2GO. Primers were designed for 349 EST-SSRs and 25 primer pairs were randomly picked for EST SSR study. Out of these, 16 primer pairs could be optimized for amplification in different accessions of Z. officinale as well as other species belonging to Zingiberaceae. GES454, GES466, GES480 and GES486 markers were found to exhibit 100% cross-transferability among different members of Zingiberaceae.     

Diversity of root-endophytic <Emphasis Type="Italic">Trichoderma</Emphasis> from Malaysian Borneo

Trichoderma species form endophytic associations with plant roots and may provide a range of benefits to their hosts. However, few studies have systematically examined the diversity of Trichoderma species associated with plant roots in tropical regions. During the evaluation of Trichoderma isolates for use as biocontrol agents, root samples were collected from more than 58 genera in 35 plant families from a range of habitats in Malaysian Borneo. Trichoderma species were isolated from surface-sterilised roots and identified following analysis of partial translation elongation factor-1α (tef1) sequences. Species present included Trichoderma afroharzianum, Trichoderma asperelloides, Trichoderma asperellum, Trichoderma guizhouense, Trichoderma reesei, Trichoderma strigosum and Trichoderma virens. Trichoderma asperellum/T. asperelloides, Trichoderma harzianum s.l. and T. virens were the most frequently isolated taxa. tef1 sequence data supported the recognition of undescribed species related to the T. harzianum complex. The results suggest that tropical plants may be a useful source of novel root-associated Trichoderma for biotechnological applications.     

Abscisic acid biosynthesis under water stress: anomalous behavior of the 9-<Emphasis Type="Italic">cis</Emphasis>-epoxycarotenoid dioxygenase1 (<Emphasis Type="Italic">NCED1</Emphasis>) gene in rice

The gene NCED1 encodes 9-cis-epoxycarotenoid dioxygenase, which catalyzes oxidative cleavage of 9-cis-epoxycarotenoids neoxanthin and violaxanthin to xanthoxin, a key step in the biosynthesis of abscisic acid (ABA) in higher plants. In the present study, the complete NCED1 of 1 917 bp was cloned and characterized from rice (Oryza sativa L. cv. N22) as no earlier reports were available for its characterization from the indica cultivar. The NCED1 had no intron and encoded a protein of 639 amino acids with a predicted molecular mass of 68.62 kD and pI of 6.07. The aliphatic index and grand average of hydropathicity were found to be 77.04 and -0.148, respectively. Multiple alignment analysis revealed that the sequence shared a high identity with the Oryza sativa japonica group (100 %) followed by Triticum aestivum (90 %), Hordeum vulgare (90 %), and Zea mays (89 %). The enzyme had a RPE65 domain of 476 amino acid residues. The RPE65 domain requires Fe(II) as a cofactor coordinated with 4 histidine residues and 3 glutamic acid residues. The phylogenic tree shows that NCED1 of japonica rice and NCED1 of indica rice were in the same group. They might have been evolved from a common ancestor. Analysis with a PSORT III tool shows that NCED is a chloroplastic protein. The real-time quantitative PCR and RNA-sequencing studies show that the expression of NCED1 was progressively reduced with increasing water stress, and a negative correlation between expression of OsNCED1 and severity of stress was established. Further, NCED1 expression negatively correlated with ABA accumulation under water stress whereas in some other species, its expression increased along with ABA accumulation. This might be due to feedback inhibition of the ABA biosynthesis in rice.