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Panax notoginseng is a famous Chinese herbal medicine, but the root rot disease mainly caused by Fusarium solani severely reduces the yield and quality of its medicinal materials. The defense priming in P. notoginseng through exogenous application of signaling molecule will supply theoretical support for the exogenous regulation of disease resistance in P. notoginseng. In this study, the exogenous application of methyl jasmonate (MeJA) increased P. notoginseng’s resistance to F. solani. Furthermore, the P. notoginseng transcriptome during F. solani infection was investigated through next-generation sequencing to uncover the resistance mechanism of P. notogingseng induced by MeJA. The de novo assembly of transcriptome sequences produced 80,551 unigenes, and 36,771 of these unigenes were annotated by at least one database. A differentially expressed gene analysis revealed that a large number of genes related to terpenoid backbone biosynthesis, phenylalanine metabolism, and plant–pathogen interactions were predominantly up-regulated by MeJA. Moreover, jasmonic acid (JA) biosynthesis-related genes and the JA signaling pathway genes, such as linoleate 13S-lipoxygenase, allene oxide cyclase, allene oxide synthase, TIFY, defensin, and pathogenesis-related proteins, showed increased transcriptional levels after inoculation with F. solani. Notably, according to the gene expression analysis, JA and ethylene signaling pathways may act synergistically to positively regulate the defense responses of P. notoginseng to F. solani. JA signaling appears to play a vital role in P. notoginseng responses to F. solani infection, which will be helpful in improving the disease resistance of P. notoginseng cultivars as well as in developing an environmentally friendly biological control method for root rot disease.

Jasmonic acid (JA) is thought to be involved in plant responses to cadmium (Cd) stress, but the underlying molecular mechanisms are poorly understood. Here, we show that Cd treatment rapidly induces the expression of genes promoting endogenous JA synthesis, and subsequently increases the JA concentration in Arabidopsis roots. Furthermore, exogenous methyl jasmonate (MeJA) alleviates Cd-generated chlorosis of new leaves by decreasing the Cd concentration in root cell sap and shoot, and decreasing the expression of the AtIRT1, AtHMA2 and AtHMA4 genes promoting Cd uptake and long-distance translocation, respectively. In contrast, mutation of a key JA synthesis gene, AtAOS, greatly enhances the expression of AtIRT1, AtHMA2 and AtHMA4, increases Cd concentration in both roots and shoots, and confers increased sensitivity to Cd. Exogenous MeJA recovers the enhanced Cd-sensitivity of the ataos mutant, but not of atcoi1, a JA receptor mutant. In addition, exogenous MeJA reduces NO levels in Cd-stressed Arabidopsis root tips. Taken together, our results suggest that Cd-induced JA acts via the JA signaling pathway and its effects on NO levels to positively restrict Cd accumulation and alleviates Cd toxicity in Arabidopsis via suppression of the expression of genes promoting Cd uptake and long-distance translocation.

Several fermentations with consecutively feeding of acetate/butyrate were conducted in a 7 L fermentor and the results indicated that exogenous acetate/butyrate enhanced solvents productivities by 47.1% and 39.2% respectively, and changed butyrate/acetate ratios greatly. Then extracellular butyrate/acetate ratios were utilized for calculation of acids rates and the results revealed that acetate and butyrate formation pathways were almost blocked by corresponding acids feeding. In addition, models for acetate/butyrate feeding fermentations were constructed by graph theory based on calculation results and relevant reports. Solvents concentrations and butanol/acetone ratios of these fermentations were also calculated and the results of models calculation matched fermentation data accurately which demonstrated that models were constructed in a reasonable way.

We previously found that a methanolic extract of the stems of Sambucus sieboldiana inhibited bone resorption in organ culture. In this study, we further fractionated the methanol extract guided by the activity towards bone resorption stimulated by parathyroid hormone (PTH) in vitro. The ethyl acetate fraction (EtOAc Fr.) of the methanolic extract inhibited PTH-stimulated bone resorption of neonatal mouse bones, and the inhibitory activity was more potent than those of other fractions. Oral administration of the EtOAc Fr. (50 and 100 mg/kg/d) to ovariectomized (OVX) rat prevented the decrease in bone mineral density (BMD) of the lumbar (L2-4) vertebra, indicating that the EtOAc Fr. is effective in vivo. Furthermore, the EtOAc Fr. (50, 100 and 150 mg/kg/d) decreased the serum calcium level elevated in low calcium dietary rats. The phenolic constituents of the EtOAc fraction were examined for their inhibitory effect on bone resorption stimulated by PTH in neonatal mouse bone. Among them, vanillic acid, vanillin and coniferyl alcohol showed significant inhibitory effects on bone resorption. Of the compounds examined, vanillic acid was found to have a significant inhibitory effect on the decrease of BMD in OVX mice. Therefore, the EtOAc Fr. of S. sieboldiana showed a suppressive effect on bone resorption in vitro and in vivo. In addition, the inhibitory effects of the EtOAc Fr. on bone resorption may be at least partly due to the inhibitory action of vanillic acid.

In this study, we attempted to increase butanol/acetone ratio and total solvent productivity in ABE fermentations with corn- and cassava-based media, by consecutively feeding a small amount of butyrate/acetate during solventogenic phase to weaken the metabolic strengths in butyrate/acetate closed-loops. Consecutively feeding a small amount of butyrate (a total of 3.0 g/L-broth) is most effective in improving performance of corn-based ABE fermentations, as it simultaneously increased average butanol/acetone ratio by 23 % (1.92–2.36) and total solvent productivity by 16 % (0.355–0.410 g/L/h) as compared with those of control. However, the butyrate feeding strategy could not improve butanol/acetone ratio and total solvent productivity in cassava-based ABE fermentations, where the metabolic strength of butyrate closed-loop had already been very low.

Taking the flue-cured tobacco variety of "Longjiang 911" from Heilongjiang Province of Northeast China as test material, a pot experiment was conducted to study the effects of foliar spraying different concentration methyl jasmonate (MeJA) on the seedlings leaf chlorophyll content and chlorophyll fluorescence characteristics during the transplantation stage under drought and re-watering. Under drought condition, the leaf chlorophyll content, maximum fluorescence (F(m)), potential activities of PSII (F(v)/F(o)), maximum photochemical efficiency (F(v)/F(m)), actual photochemical efficiency (psi(PSII)), apparent electron transport rate (ETR), and photochemical quenching (q(P)) decreased, but the minimal fluorescence (F(o)) and non-photochemical quenching (q(N)) increased. Foliar spraying 0.2 and 0.5 mmol x L(-1) of MeJA had obvious positive effects in mitigating the decrease of F(v)/F(m), F(v)/F(o), phi(PSII), ETR, and q(P) and the increase of q(N) under drought stress, while spraying 1.0 mmol x L(-1) of MeJA had lesser effects. After re-watering, all the leaf chlorophyll fluorescence indices had obvious recovery, and spraying MeJA made the indices more close to the original levels before drought. It was suggested that foliar spraying MeJA could alleviate the degradation of chlorophyll and play definite role in protecting the PSII under drought stress, decrease the damage of drought stress on the seedlings, promote the rapid MeJA recovery of chlorophyll fluorescence parameters after re-watering, and thus, ensure the regrowth of flue-cured tobacco seedlings.

An asymmetric direct aldol reaction of acetoacetals is described. Under the catalysis of a simple chiral primary amine, the direct aldol reactions of acetoacetals occur exclusively on the gamma-position to give vinylogous-type aldol products with high diastereo- and enantioselectivity.

To observe the effects of different introcular irrigating solutions on the viability of retinal neuron cells, their antioxidant ability, and to find the ideal introcular irrigating solution.Retinal neuron cells from Sprague Dawley rats (postnatal 1 - 3 days) were cultured in the 4 different introcular irrigating solutions which were BSS plus, BSS plus + drugs (tobramycin1.6 ten thousand unit/L, desamethasone 16 mg/L and adnephrin 1 mg/L), new irrigating solution and lactated Ringer's solution + drugs. Cell viability was determinated by MTT [3,(4,5-Dimethylthiazol-2-yl)2,5-diphenyl-tetrazolium bromide] assay, LDH release was tested by LDH assay and apoptotic cell death was evaluated by the TUNEL (TdT-mediated dUTP nick-end labeling) assay after retinal neuron cells were cultured in the different introcular irrigating solutions for 4, 12, 24, 48 hours. MDA (malondialdehyde) production was tested after the cells exposed to 30 micro mol/L H(2)O(2) for 4 hours. All data was analyzed in Dunnett's ANOVA way.The cell viability was decreased and the rate of LDH released and cell apoptosis was increased. These effects were shown to be time-dependent for the same solution. At the same time point, the effects on cellular survive was variable in deferent introcular irrigating solutions, BSS plus is the lowest, BSS plus + drugs and modified irrigating solution are midst, and lactated Ringer's solution + drugs is the highest. The result of MDA assay showed that both BSS plus and modified irrigating solution can inhibit the oxidative damage induced by H(2)O(2).Modified introcular irrigating solution may be an better introcular irrigating solution according to its little effect on cell viability, its antioxidant function and lower cost.