Effect of different fertilization treatments on growth,secondary metabolites,and seed yield and quality of Perilla frutescens / 中国中药杂志

Perilla frutescens,an annual plant in Labiatae family,is grown throughout China and can be used for medicine purposes and as food additives. The present field experiment was carried out to study the effects of different fertilizer treatments on the concentrations and accumulations of antioxidant components,including flavonoids and polyphenols,growth,seed yields and qualities of this plant.The main aim of this study is to provide farmers some advice for improving the yields and qualities of P. frutescens in theory and practice.Five treatments were set up,including a no fertilizer control(CK),chemical fertilizers(CF),organic fertilizers(M),organic fertilizers plus chemical fertilizers at the rates of 1 ∶1 and 1 ∶3 in terms of nitrogen(50 M,25 M). Plant growth parameters were recorded and total flavonoids and polyphenols were determined in three key growth stages of P. frutescens. At the fast growth period,samples of roots,leaves,and stems were collected for determining a total of flavonoids and polyphenols as well as DPPH removal rate of ethanol extracts. Seed yields and qualities were also recorded at harvest. The results showed fertilization enhanced growth and seed yields although no significant difference was observed in growth and seed yields in inorganic-organic fertilizer treatments. The total flavonoids,polyphenols,and DPPH removal rate of ethanol extracts followed the sequence leaves>stems>roots,indicating synthesis of these metabolites in the leaves. DPPH removal rate showed a positive linear correlation with total flavonoid and polyphenol concentrations. In addition,organic-inorganic fertilization significantly increased the numbers of both effective panicles and paniclegrains. Fertilizer treatments had no effect on seed qualities of P. frutescens,while 50 M achieved the highest yield,which increased by 14. 73% compared to CF alone. In general,50 M increased antioxidant components,biomass,and seed yield of P. frutescens,meriting advocate in cultivation.

Influence of continuous cropping on growth of Artemisia annua and bacterial communities in soil / 中国中药杂志

In this study, several types of Artemisia annua in soil, including the soil which had not been planted, or planted for one year, or continuously planted for three or five years were collected, in order to study the influences of continuous cropping on the growth of A. annua, content of artemisinin, available nutrient of soil, and bacterial community structure through adopting routine analysis and Illumina MiSeq high-throughput sequencing. The results showed that continuous cropping inhibited significantly the growth of A. annua and reduced leaf biomass, content and yield of artemisinin, with the maximum decreasing amplitude of 30.20%, 7.70% and 35.58% respectively. The content of soil organic matter, available nitrogen, available phosphorus and 16S rRNA sequence number were increased to different extents after continuous cropping of A. annua. According to the results of high-throughput sequencing, 634-812 types of common bacteria belonged to 21 categories were planted in different soil of A. annua with different planting years, which represented that the distribution distance of the point of bacterial community with different years among coordinate system of principal component was relative distant, and community structure had significant changes (P<0.05). As the planting years increased, the abundance of Actinobacteria, Chloroflexi, Gemmatimonadetes decreased in contrast to Proteobacteria, Acidobacteria and Verrucomicrobia. In the top 20 types of predominant bacteria,Nitrospira japonica and Nitrospira disappeared, among which, only Gemmatimonadaceae, Micromonosporaceae, Nitrosomonadaceae, Xanthobacteraceae, and unculture bacterium JG30-KF-AS9 were similar, indicating that the planting and continuous cropping of A. annua selectively inhibited the growth and reproduction of soil bacteria, and influenced the supply and transform of soil nutrient, leading to a poor growth and resulting in reduction of artemisinin content and yield. Therefore, it is necessary to advocate crop rotation in the process of planting A. annua.

Effect of fibrous root extract of Coptis chinensis on soil microbes and enzyme activities / 中国中药杂志

Coptis chinensis is widely used as Chinese medicine herbs and serious soil problems occur after continual cultivation of this medicinal plant. In the preset experiment, fibrous root extract of C. chinensis (REC) was added into soil to study the effect of REC on microbes and enzyme activity in soil. The results showed that both bacteria and actinomycetes decreased by about 2 times in contrast to fungi, which increased by about 3 folds. Phosphorus bacteria, potassium bacteria, azotobacter, ammonia bacteria, and nitrifying bacteria were also reduced significantly by REC, suggesting the inhibition of nitrogen biofixation and supply, mobilization of phosphorus and potassium, ad plant growth promotion as REC added into soil. There were multiple influences of REC on soil enzyme activities. Invertase activity was stimulated, while urease was inhibited and dehydrogenase unchanged by REC, indicating the interference of biochemical reactions in soil. In addition, type and total content of phosphorus lipid fatty acids (PLFAs) , the signature of microbes, decreased while the ratio of bacterium to fungus PLFAs increased as REC increased in soil, which suggested that fungi increased relatively with bacteria decreased thereby leading to easy occurrence of crop fungus diseases following cultivation of C. chinensis. The decrease in diversity and evenness indexes of microbial community in soil by REC indicated soil ecosystem deterioration and reduction of microbial groups and densities in soil. Therefore, allelopathic chemicals released from the roots of C. chinensis could change microbial community structure and resulted in serious soil problems by continual cropping of this medicinal plant.

Allelopathic effect of artemisinin on green algae / 中国中药杂志

To study the growth effects of differing concentrations of artemisinin on green algae and to evaluate the ecological risk. The effects of artemisinin on the growth and the content change of chlorophyll, protein, oxygen, conductivity, SOD, CAT, MDA in Chlorella pyrenoidosa and Scenedesmus oblique were studied through 96 h toxicity tests. Artemisinin accelerated the growth of algae at a lower concentration ( <40 microg . L-1) with content increase of chlorophyll or protein and so on, and it inhibited the growth of algae at higher concentration ( >80 microg . L-1). The content of chlorophyll or protein in algae cells reduced with the increasing concentration of artemisinin, exhibiting the good concentration-effect relationship. SOD and CAT activity was stimulated at low concentrations ( <40 microg . L-1 ) and inhibited at high concentrations ( >80 microg . L- 1). However, MDA content increased significantly with the increase of concentration. According to the seven kinds of indicators changes, the time-response and dose-response suggested that the surfactant first hurt in Ch. pyrenoidosa was damaging membrane by changing membrane lipid molecules soluble. And primary mechanism on Chlorophyta cells might be related to the oxidation damage of lipid and other biological large molecules caused by artemisinin. The large-scale intensive planting of Artemisia annua may reduce the surrounding water productivity.

Effect of fertilization on phenolic components and antioxidant activities of Artemisia annua / 中国中药杂志

<p><b>OBJECTIVE</b>A pot experiment with variable fertilizer treatments was carried out to study the influence of fertilization on the concentration and accumulation of polyphenols, scopoletin, chrysosplenol-D and chrysosplenetin in roots, stems and leaves and their antioxidant activities. The main aims were to fertilize scientifically in cultivation of Artemisia annua and improve the quality of the harvest organs.</p><p><b>METHOD</b>These active components in leaves, stems and roots in the squaring stage were analyzed by HPLC and antioxidant activities of the extracts were evaluated by ultraviolet visible light colorimetric method.</p><p><b>RESULT</b>The result showed the highest concentration of polyphenols, scopoletin, chrysosplenol-D and chrysosplenetin was in leaves, followed by stems and the lowest in roots. The antioxidant activities of the leaf extracts correlated positively with the concentrations of polyphenols, scopoletin, chrysosplenol-D and chrysosplenetin. Furthermore, fertilization promoted significantly the growth of A. annua, the biomass was increased by 57.37% (chemical fertilizer), 91.63% (mixture of chemical fertilizer and manure) and 92.27% (manure), respectively, compared to the blank control (without fertilizer). Fertilization, particularly mixture fertilization of chemical fertilizer and manure, increased generally the concentration and accumulation of polyphenols, scopoletin, chrysosplenol-D and chrysosplenetin as well as DPPH x scavenging ratio.</p><p><b>CONCLUSION</b>Scopoletin, chrysosplenol-D and chrysosplenetin could be synthesized and stored mainly in leaves. The leaves might thus be the chief organ of A. annua for medical treatment. Finally, the mixture fertilization of chemical fertilizer and manure should be used to increase the yield and quality of A. annua.</p>

Allelopathic effects of extracts from fibrous roots of Coptis chinensis on two leguminous species / 中国中药杂志

An experiment was carried out to study the allelopathic effects of Coptis chinensis fibrous root extracts (CRE) on the germination and seedling growth of Vicia faba and Pisum sativum in order to alleviate the allelopathic effects and increase land productivity. The seeds of both garden pea (P. sativum) and broad been (V. faba) were germinated in CRE solution of various concentrations, the germination rate, seedling growth and related physiological indexes were measured. The result indicated that there were no significant effects of CRE in low concentrations on seed germination, including both the rate and index, and seed vitality and membrane permeability. With the increment of CRE concentrations, however, the high seed membrane permeability and germination inhibition were observed. For example, the germination rates were reduced by 23.4% (P. sativum) and 9.5% (V. faba), respectively, in CRE solution with 800 mg . L-1. Simultaneously, soluble sugars and the free amino acids in the seeds were lower than those in the control (without CRE) after soaking seeds in CRE solutions. In addition, the seedling growth and nitrate reductase activity were stimulated by CRE at low concentrations in contrast to high concentrations which behaved otherwise and inhibited the nutrient utilization in endosperm. Therefore, the large amount of allelochemicals released from the roots and remains of C. chinensis in soils could inhibit the seed germination and seedling growth of legumes, which may lead to decrease even fail crop yields after growing this medical plant.

Detection of mutants of the "a" determinant region of hepatitis B surface antigen S gene among Wuhan childhood patients / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate whether the presence of HBV mutant in vaccinees simply reflects the prevalence of HBV mutant in a specific geographic area or is indeed due to the immune pressure induced by vaccination.</p><p><b>METHODS</b>HBV S genes were amplified by using polymerase chain reaction (PCR) and DNA sequence analysis of the "a" determinant was performed on sera from 30 childhood patients with immunoprophylaxis and 30 patients without vaccinations.</p><p><b>RESULTS</b>Mutations of the "a" determinant were detected in 8 of the 60 patients. They were all of the adw subtype. The prevalence of amino acid substitutions as detected by direct sequencing was higher in those fully-vaccinated than of those not vaccinated. In all 8 vaccinated and also with detectable mutants, the mean age was older than the other vaccinated children.</p><p><b>CONCLUSION</b>The prevalence of mutants is related to HBV subtypes and genotypes. Universal vaccination has accelerated an accumulation of HBsAg "a" determinant mutants with amino acid changes critical for immune escape in vaccinated children who became carriers. This suggests that new vaccination strategies should be considered.</p>

Detection of SEN virus (subtype D/H) infection in Shenzhen / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the prevalence of newly identified single-chain DNA virus (SENV) infection in Shenzhen.</p><p><b>METHODS</b>Nested polymerase chain reaction (nPCR) was established using primers from ORF1 region of SENV genome. Six hundred and one sera samples from different populations were detected for SENV DNA (D and H subtype) by nPCR. Products of PCR were cloned into T-vector and sequenced.</p><p><b>RESULTS</b>The positive rates of SENV DNA in different populations were as followed: 27.8% in patients with hepatitis B, 22.2% in patients with hepatitis C, 26.9% in hemodialysis patients and 39.3% in IDUs. Among blood donors, the positive rates of SENV DNA were 28.1% in unqualified blood donors, 31.3% in blood donors with an elevated ALT levels and 15.1% in qualified blood donors. The infection rates of SENV in unqualified blood donors and blood donors with an elevated ALT levels were obviously higher than in qualified blood donors (chi(2) = 8.29, P < 0.01 and chi(2) = 6.03, P < 0.01). There was a 6.8% difference of nucleotide between SENV-D standard subtype and 6 isolates with 13.5% difference of nucleotide between SENV-H standard subtype and 4 isolates from Shenzhen.</p><p><b>CONCLUSION</b>Results suggested that SENV infection was common in high-risk groups in Shenzhen.</p>

The probability of microbiological contamination during the collection and processing of umbilical cord blood / 中国实验血液学杂志

To study the pathogens incidences in cord blood and the efficiency of different detective methods, 60 samples were drawn and reserved from collected and processed cord blood, respectively. The BACTEC 9050 system, improved Martin/thioglycollate broth (22 degrees C) and thioglycollate broth (35 degrees C) were employed to detected bacteria (including fungus) at the same time. Two hundred and six cord blood serum samples were used to detect the HBV DNA and HCV RNA by molecular biology technique, HBsAg, Anti-HBC, Anti-HCV, Anti-HCMV-IgM, HTLV-1, HTLV-2, HIV-1 and HIV-2 by ELISA and RBC agglutination test were used to detect the TPHA. Results showed that using BACTEC 9050 system, the incidence of bacteria and fungus was 3.33% and 0% respectively in collected cord blood; in processed cord blood, the rates increased to 6.67% and 1.67%, respectively. The sensitivity of BACTEC 9050 was higher than that of Martin/thioglycollate broth (22 degrees C/35 degrees C) culture. In 206 serum samples, the positive rate of HBV DNA was 5.8%, HCV RNA was 2.4%, HBsAg was 2.4%, HCMV-IgM was 1.89%, HCV was 2.4% and Anti-HBC was 29.4%. In those samples that Anti-HBC was positive, the positive rate of HBV DNA was 6.7%. It was concluded that the incidences of microbiological contamination in cord blood were high. The routine culture system would lead to false negative results of obligate anaerobes. It was necessary to replace the current culture system with improved system, such as BACTEC 9050 system. The molecular biology technique would make up for the default of ELISA.