The present study explored the physiological mechanism of the effects of different pH treatments on the growth, physiological characteristics, and stachydrine biosynthesis of Leonurus japonicus to provide references for the cultivation and quality control of L. japonicus. Under hydroponic conditions, different pH treatments(pH 5,6,7,8) were set up. The growth, physiology, and the content of stachydrine and total alkaloids of L. japonicus, as well as the content of key intermediate products in stachydrine biosynthesis pathway(i.e., pyruvic acid, α-ketoglutaric acid, glutamic acid, and ornithine) were monitored to explore the physiological mechanism of the effects of pH on the growth and active components of L. japonicus. The results showed that L. japonicus. could grow normally in the pH 5-8 solution. The pH treatment of neutral acidity was more conducive to the accumulation of photosynthetic pigments and the increase in soluble protein in leaves of L. japonicus. to promote its growth and yield. However, since stachydrine is a nitrogen-containing pyrrolidine alkaloid, its synthesis involves the two key rate-limiting steps of nitrogen addition: reductive ammoniation reaction and Schiff base formation reaction. High pH treatments promote the synthesis and accumulation of substrates and products of the above two reactions, indicating that the alkaline environment can promote the nitrogen addition reaction, thereby promoting the biosynthesis and accumulation of stachydrine.
Leonurus/chemistry* ; Hydroponics ; Alkaloids ; Nitrogen ; Hydrogen-Ion Concentration

This article introduced the theorem and method of hydroponics. Some examples of studies in agriculture and forestry were presented, the effects of elements, environmental stress and hormones on physiology of medicinal plants by using hydroponics were analyzed. It also introduced the feasibility and advantage of hydroponics in intermediate propagation and allelopathy of medicinal plant. And finally it made the conclusion that the way of hydroponics would be widely used in medicinal plant study.
Culture Media ; Hydroponics ; methods ; Plant Growth Regulators ; pharmacology ; Plants, Medicinal ; drug effects ; growth & development ; physiology

The physiological response and bioaccumulation of 2-year-old Panax notoginseng to cadmium stress was investigated under a hydroponic experiment with different cadmium concentrations (0, 2.5, 5, 10 μmol · L(-1)). Result showed that low concentration (2.5 μmol · L(-1)) of cadmium could stimulate the activities of SOD, POD, APX in P. notoginseng, while high concentration (10 μmol · L(-1)) treatment made activities of antioxidant enzyme descended obviously. But, no matter how high the concentration of cadmium was, the activities of CAT were inhibited. The Pn, Tr, Gs in P. notoginseng decreased gradually with the increase of cadmium concentration, however Ci showed a trend from rise to decline. The enrichment coefficients of different parts in P. notoginseng ranked in the order of hair root > root > rhizome > leaf > stem, and all enrichment coefficients decreased with the increase of concentration of cadmium treatments; while the cadmium content in different parts of P. notoginseng and the transport coefficients rose. To sum up, cadmium could affect antioxidant enzyme system and photosynthetic system of P. notoginseng; P. notoginseng had the ability of cadmium enrichment, so we should plant it in suitable place reduce for reducing the absorption of cadmium; and choose medicinal parts properly to lessen cadmium intake.
Cadmium ; pharmacokinetics ; toxicity ; Hydroponics ; Panax notoginseng ; drug effects ; growth & development ; metabolism ; Photosynthesis ; drug effects ; Superoxide Dismutase ; metabolism

OBJECTIVETo develop a hydroponic Nicotiana cultivation system for rapid and high-yield transient expression of recombinant proteins under laboratory conditions.

METHODSTo establish the hydroponic cultivation system, several parameters were examined to define the optimal conditions for the expression of recombinant proteins in plants. We used the green fluorescent protein (GFP) and the geminiviral plant transient expression vector as the model protein/expression vector. We examined the impact of Nicotiana species, the density and time of Agrobacterium infiltration, and the post-infiltration growth period on the accumulation of GFP. The expression levels of GFP in Nicotiana leaves were then examined by Western blotting and ELISA.

RESULTSOur data indicated that a hydroponic Nicotiana cultivation system with a light intensity of 9000 LX/layer, a light cycle of 16 h day/8 h night, a temperature regime of 28 degrees celsius; day/21 degrees celsius; night, and a relative humidity of 80% could support the optimal plant growth and protein expression. After agroinfiltration with pBYGFPDsRed.R/LBA4404, high levels of GFP expression were observed in both N. benthamiana and N. tobaccum (cv. Yuyan No.5) plants cultured with this hydroponic cultivation system. An optimal GFP expression was achieved in both Nicotiana species leaves 4 days after infiltration by Agrobacterium with an OD(600) of 0.8. At a given time point, the average biomass of N. tobaccum (cv. Yuyan No.5) was significantly higher than that of N. benthamiana. The leaves from 6-week-old N. benthamiana plants and 5-week-old N. tobaccum (cv. Yuyan No.5) plants could be the optimal material for agroinfiltration.

CONCLUSIONWe have established a hydroponic cultivation system that allows robust growth of N. benthamiana and N. tobaccum (cv. Yuyan No.5) plants and the optimal GFP expression in the artificial climate box.

Gene Expression Regulation, Plant ; Genetic Vectors ; Green Fluorescent Proteins ; biosynthesis ; genetics ; Hydroponics ; methods ; Plants, Genetically Modified ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; Tobacco ; genetics ; growth & development

OBJECTIVETo understand the genotype and the mutation of amino acid (aa) in the major hydrophilic region (MHR) of hepatitis B virus (HBV) among the hepatitis B cases under surveillance in Liaoning province.

METHODSThe serum samples were collected from hepatitis B cases under surveillance in Liaoning. The complete S gene of HBV were amplified and sequenced. The aa sequences were analyzed with bioinformatics software.

RESULTSA total of 81 sequences of S gene of HBV were ontained, including 7 sequences of genotype B (8.64%), 70 sequences of genotype C (86.42%) and 4 sequences of genotype D (4.94%). The mutation rate of aa of MHR of S gene was 4.87%. The mutation rate of T126I was highest (8.64%). The overall prevalence of mutant strain of MHR was 49.38% (40/81), and it was 42.86% for genotype B (3/7), 47.14% for genotype C (33/70) and 100% for genotype D (4/4). Statistical analysis revealed that there was no age, sex, genotypes and anti-HBc IgM (±) specific significant differences in aa mutant strains prevalence, while the difference between ALT abnormal group (ALT ≥ 43 IU/L) and ALT normal group (ALT<43 IU/L) was significant (P < 0.05).

CONCLUSIONAmong the hepatitis B cases under surveillance in Liaoning, HBV genotype C predominant, followed by genotype B and genotype D. The mutation of aa in MHR of HBV detected in this study was consistent with previous research results. It is necessary to strengthen the surveillance for HBV mutation to provide accurate information for the development of hepatitis B prevention and control measures.

Amino Acid Sequence ; China ; DNA, Viral ; Genotype ; Hepatitis B ; genetics ; Hepatitis B Surface Antigens ; Hepatitis B virus ; genetics ; Humans ; Hydroponics ; Mutation ; Prevalence