Phytochemical profiling and allelopathic effect of garlic essential oil on barnyard grass (Echinochloa crusgalli L.).

In agriculture, barnyard grass (Echinochloa crusgalli L.) is one of the most harmful weeds in rice fields now. In order to identify active ingredients which had inhibiting effect on barnyard grass (Echinochloa crusgalli L.), we evaluated several possible natural plant essential oils. Essential oils from twelve plant species showed inhibitory activity against barnyard grass seedlings and root length. The garlic essential oil (GEO) had the most significant allelopathic effect (EC50 = 0.0126 g mL-1). Additionally, the enzyme activities of catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD) increased during the first 8 hours of treatment at a concentration of 0.1 g mL-1 and then declined. The activities of CAT, SOD and POD increased by 121%, 137% and 110% (0-8h, compared to control), and decreased (8-72h, compared to the maximum value) by 100%, 185% and 183%, respectively. The total chlorophyll content of barnyard grass seedlings decreased by 51% (0-72h) continuously with the same dosage treatment. Twenty constituents of GEO were identified by gas chromatography-mass spectrometry, and the herbicidal activity of two main components (diallyl sulfide and diallyl disulfide) was evaluated. Results showed that both components had herbicidal activity against barnyard grass. GEO had a strong inhibitory effect (~88.34% inhibition) on barnyard grass growth, but safety studies on rice showed it did not have much inhibitory effect on rice seed germination. Allelopathy of GEO provide ideas for the development of new plant-derived herbicides.

Rumen-protected glucose stimulates the secretion of reproductive hormones and the mTOR/AKT signaling pathway in the ovaries of early postpartum.

This study was conducted to determine the response of the reproductive hormones and the mTOR/AKT/PI3K pathway in the ovaries of postpartum dairy cows with dietary rumen-protected glucose (RPG). Twelve Holstein cows were randomly assigned to two groups (n = 6/group): the control group (CT) and the RPG group. Blood samples were collected on d 1, 7, and 14 after calving for the gonadal hormone assay. The expression of the gonadal hormones receptors and PI3K/mTOR/AKT pathways were detected using RT-PCR and Western blot. The RPG addition increased the plasma LH, E2, and P4 concentrations on d 14 after calving and upregulated the mRNA and protein expressions of the ERα, ERß, 17ß-HSD, FSHR, LHR, and CYP17A1 but downregulated StAR expression. Immunohistochemical analysis identified higher expressions of the FSHR and LHR in the ovaries of RPG-fed cows compared to CT cows. Furthermore, the protein expressions of p-AKT/AKT and p-mTOR/mTOR were significantly increased in the ovaries of RPG-fed cows compared to the CT group, but the addition of RPG did not alter the protein expression of p-PI3K/PI3K. In conclusion, the current results indicated that dietary RPG supplementation regulated gonadotropin secretion and stimulated expression of hormone receptors and the mTOR/AKT pathway in the ovaries of early postpartum dairy cows. RPG may be beneficial for the recovery of ovarian activity in post-calving dairy cows.

Physiological and transcriptomic analyses to reveal underlying phenolic acid action in consecutive monoculture problem of Polygonatum odoratum.

BACKGROUND: The root rot of fragrant solomonseal (Polygonatum odoratum) has occurred frequently in the traditional P. odoratum cultivating areas in recent years, causing a heavy loss in yield and quality. The phenolic acids in soil, which are the exudates from the P. odoratum root, act as allelochemicals that contribute to the consecutive monoculture problem (CMP) of the medicinal plant. The aim of this study was to get a better understanding of P. odoratum CMP. RESULTS: The phenolic acid contents, the nutrient chemical contents, and the enzyme activities related to the soil nutrient metabolism in the first cropping (FC) soil and continuous cropping (CC) soil were determined, and the differentially expressed genes (DEGs) related to the regulation of the phenolic acids in roots were analyzed. The results showed that five low-molecule-weight phenolic acids were detected both in the CC soil and FC soil, but the phenolic acid contents in the CC soil were significantly higher than those in the FC soil except vanillic acid. The contents of the available nitrogen, available phosphorus, and available potassium in the CC soil were significantly decreased, and the activities of urease and sucrase in the CC soil were significantly decreased. The genomic analysis showed that the phenolic acid anabolism in P. odoratum in the CC soil was promoted. These results indicated that the phenolic acids were accumulated in the CC soil, the nutrient condition in the CC soil deteriorated, and the nitrogen metabolism and sugar catabolism of the CC soil were lowered. Meantime, the anabolism of phenolic acids was increased in the CC plant. CONCLUSIONS: The CC system promoted the phenolic acid anabolism in P. odoratum and made phenolic acids accumulate in the soil.

Extraction and Hypolipidemic Activity of Low Molecular Weight Polysaccharides Isolated from Rosa Laevigata Fruits.

Three novel low molecular weight polysaccharides (RLP-1a, RLP-2a, and RLP-3a) with 9004, 8761, and 7571 Da were first obtained by purifying the crude polysaccharides from the fruits of a traditional Chinese medicinal herb Rosae Laevigatae. The conditions for polysaccharides from the R. Laevigatae fruit (RLP) extraction were optimized by the response surface methodology, and the optimal conditions were as follows: extraction temperature, 93°C; extraction time, 2.8 h; water to raw material ratio, 22; extraction frequency, 3. Structural characterization showed that RLP-1a consisted of rhamnose, arabinose, xylose, glucose, and galactose with the ratio of 3.14 : 8.21 : 1 : 1.37 : 4.90, whereas RLP-2a was composed of rhamnose, mannose, glucose, and galactose with the ratio of 1.70 : 1 : 93.59 : 2.73, and RLP-3a was composed of rhamnose, arabinose, xylose, mannose, glucose, and galactose with the ratio of 6.04 : 26.51 : 2.05 : 1 : 3.17 : 31.77. The NMR analyses revealed that RLP-1a, RLP-2a, and RLP-3a contained 6, 4, and 6 types of glycosidic linkages, respectively. RLP-1a and RLP-3a exhibited distinct antioxidant abilities on the superoxide anions, 1,1-diphenyl-2-picrylhydrazyl (DPPH), and hydroxyl radicals in vitro. RLPs could decrease the serum lipid levels, elevate the serum high-density lipoprotein cholesterol levels, enhance the antioxidant enzymes levels, and upregulate of FADS2, ACOX3, and SCD-1 which involved in the lipid metabolic processes and oxidative stress in the high-fat diet-induced rats. These results suggested that RLPs ameliorated the high-fat diet- (HFD-) induced lipid metabolism disturbance in the rat liver through the peroxisome proliferator-activated receptor (PPAR) signaling pathway. Low molecular weight polysaccharides of RLP could be served as a novel potential functional food for improving hyperlipidemia and liver oxidative stress responses.

Integrated transcriptome and microRNA profiles analysis reveals molecular mechanisms underlying the consecutive monoculture problem of Polygonatum odoratum.

Polygonatum odoratum is a historically traditional Chinese medicine plant. However, the consecutive monoculture problem (CMP) widespread in other Chinese medicine limiting their cultivation on a large scale. In this study, the physiological data showed the adverse effect of CMP on the growth of P. odoratum under the consecutive cropping (CC) compared with the first cropping (FC). Then the high-throughput sequencing of miRNA and mRNA libraries of leaves and roots from FC and CC P. odoratum plants identified 671 differentially expressed genes (DEGs) and 184 differentially expressed miRNAs and revealed that the DEGs and target genes of the miRNAs were mainly involved in starch and sucrose metabolism, phenylpropanoid and brassinosteroid biosynthesis. The KEGG analysis revealed that the DEGs between CC and FC roots were enriched in the plant-pathogen interaction pathway. This study provided the expression regulation of genes related to CMP of P. odoratum but also suggested that CMP may result in the serious damage of pathogens to roots and cause the slow growth in the consecutive cropping plants.

Purification and characterization of a soluble glycoprotein from garlic (Allium sativum) and its in vitro bioactivity.

A soluble glycoprotein was purified to homogeneity from ripe garlic (Allium sativum) bulbs using ammonium sulfate precipitation, Sephadex G-100 gel filtration, and diethylaminoethyl-52 cellulose anion-exchange chromatography. A native mass of 55.7 kDa estimated on gel permeation chromatography and a molecular weight of 13.2 kDa observed on sodium dodecyl sulfate-polyacrylamide gel electrophoresis supported that the glycoprotein is a homotetramer. ß-Elimination reaction result suggested that the glycoprotein is an N-linked type. Fourier-transform infrared spectroscopy proved that it contains sugar. Gas chromatography-mass spectrometer analysis showed that its sugar component was galactose. The glycoprotein has 1,1-diphenyl-2-picrylhydrazil free radical scavenging activity and the peroxidation inhibition ability to polyunsaturated fatty acid. These results indicated that the glycoprotein has potential for food additives, functional foods, and even biotechnological and medical applications.

Optimization of alkaline extraction and bioactivities of polysaccharides from rhizome of Polygonatum odoratum.

The present study is to explore the optimal extraction parameters, antioxidant activity, and antimicrobial activity of alkaline soluble polysaccharides from rhizome of Polygonatum odoratum. The optimal extraction parameters were determined as the following: NaOH concentration (A) 0.3 M, temperature (B) 80 °C, ratio of NaOH to solid (C) 10-fold, and extraction time (D) 4 h, in which ratio of NaOH to solid was a key factor. The order of the factors was ratio of NaOH to solid (fold, C) > extraction temperature (°C, B) > NaOH concentration (M, A) > extraction time (h, D). The monosaccharide compositions of polysaccharides from P. odoratum were rhamnose, mannose, xylose, and arabinose with the molecular ratio of 31.78, 31.89, 11.11, and 1.00, respectively. The reducing power, the 1, 1-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging rate, the hydroxyl radicals scavenging rate, and the inhibition rate to polyunsaturated fatty acid (PUFA) peroxidation of the alkaline soluble polysaccharides from P. odoratum at 1 mg/mL were 9.81%, 52.84%, 19.22%, and 19.42% of ascorbic acid at the same concentration, respectively. They also showed antimicrobial activity against pathogenic bacteria Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis, and Escherichia coli.

Guanine analogues enhance antisense oligonucleotide-induced exon skipping in dystrophin gene in vitro and in vivo.

Exon skipping has demonstrated great potential for treating Duchenne muscular dystrophy (DMD) and other diseases. We have developed a drug-screening system using C2C12 myoblasts expressing a reporter green fluorescent phosphate (GFP), with its reading frame disrupted by the insertion of a targeted dystrophin exon. A library of 2,000 compounds (Spectrum collection; Microsource Discovery System) was screened to identify drugs capable of skipping targeted dystrophin exons or enhancing the exon-skipping effect by specific antisense oligomers. The 6-thioguanine (6TG) was effective for inducing skipping of both human dystrophin exon 50 (hDysE50) and mouse dystrophin exon 23 (mDysE23) in the cell culture systems and increased exon skipping efficiency (more than threefolds) when used in combination with phosphorodiamidate morpholino oligomers (PMO) in both myoblasts and myotubes. Guanine and its analogues were unable to induce detectable skipping of exon 23 when used alone but enhanced PMO-induced exon skipping significantly (approximately two times) in the muscles of dystrophic mdx mouse in vivo. Our results demonstrate that small-molecule compounds could enhance specific exon skipping synergistically with antisense oligomers for experimental therapy to human diseases.