Research progress on pesticide residues of Panax notoginseng / 中国中药杂志

Panax notoginseng is a perennial Chinese medicinal plant, which has serious continuous cropping obstacles and is prone to a variety of diseases and insect pests during the growth process. At present, the prevention and control of pests and diseases is mainly carried out through chemical pesticides, and the consequent pesticide residues of P. notoginseng have attracted much attention. This study reviewed the types and detection methods of pesticide residues in P. notoginseng from 1981 to 2021, and compared the limits of pesticide residues in P. notoginseng in China and abroad to provide a reference for rational application of pesticides in P. notoginseng and quality control of medicinal materials, thereby promoting the sustainable development of the P. notoginseng industry in China. Currently, there are only 40 published papers on pesticide residues of P. notoginseng, which is indicative of a serious problem of insufficient research. At present, hundreds of pesticide residues in P. notoginseng can be detected simultaneously by using chromatography-tandem mass spectrometry. The pesticides detected have gradually changed from early prohibited ones, such as dichlorodiphenyl trichloroethane(DDT), benzene hexachloride(BHC), and parathion, to low toxic ones(e.g., dimethomorph, procymidone, propicona-zole, and difenoconazole). The dietary risk from pesticide residues in P. notoginseng is low, which would not cause harm to consu-mers. This study concluded that in the future, the development of the quality standard for pesticide residues of P. notoginseng should be actively carried out. To increase the pesticides used in actual production in the quality standard based on the existing ones and to guide farmers to use pesticides scientifically will be the focus of future work.

Attenuation of anti-measles antibody in the healthy population aged 1-14 years old in an urban district， Shanghai / 上海预防医学

Objective:To determine the level of anti-measles antibody in healthy population aged 1-14 years old in Shanghai， and project the risk of measles incidence in adult population in the future， which may provide evidence for enhancing the measles immunization strategy. Methods:A cross-sectional study was conducted to collect the serum of healthy people aged 1-14 years old in an urban district hospital in Shanghai. Serum concentration of anti-measles IgG antibody was examined by enzyme-linked immunosorbent assay （ELISA） and dynamics of IgG antibody was compared. Results:The prevalence of anti-measles antibody in healthy people aged 1-14 years old was determined to be 95.29%， and the antibody protection rate was 61.86%. There was no significant difference in the distribution of antibody between men and women （P>0.05）. However， there was statistical difference in the distribution of antibody among different age groups （P<0.05）， in which the antibody showed a decreasing trend with age， especially after the age of 10 years. The lowest prevalence of anti-measles antibody and protection rate were observed in the population aged 13-14 years old， which were 87.41% and 22.96%， respectively. The GMT was 2.667 1 （equal to the concentration of anti-measles IgG antibody being 464.62 mIU/mL）. According to the fitting model Ŷ =3.217-0.04X（R2=0.943，P<0.05）， the antibody protection rate was projected to decrease to zero in the population aged 19-20 years old， whereas the anti-measles antibody was to zero in the population aged 29-30 years old . Conclusion:As there is almost no natural infection of measles，the anti-measles antibody after measles vaccine immunization showed a linearly decreasing trend with age after measles immunization．It is recommended that people aged 10-15 years should be administered intensive immunization for prevention of adults measles，which could be incorporated into current measles immunization strategies.

Effect of different water conditions on Panax notoginseng seeds after-ripening and germination physiology / 中国中药杂志

Effect of different water conditions on the physiological indexes (e.g.seed water content, vigor, antioxidase activities)of Panax notoginseng seeds were studied under process of after-ripening and germination.The results showed show that compared with 2.5% treatment, under the treatment of 5%, P.notoginseng seeds possessed stable seed water content, the seed vigor was exceed by 51%,variation of antioxidant enzyme (SOD, POD, CAT) activity and malondialdehyde (MDA) content were small, crude fat and total sugar content decreased significantly.With the increase of PEG 6000 concentration, the germination characteristic indexes obviously decreased, antioxidase activities increased firstly and decreased afterwards, content of MDA, soluble protein and total sugar increased obviously.There were significant positive correlation between germination characteristic indexes and osmotic substance content(r>0.900, P<0.01), and significant negative correlation with MDA (r>0.900, P<0.01).In conclusion, because the characteristic of dehydration intolerance of P.notoginseng seeds, 5% water content of sand burying stratification treatment was the best for after-ripening, 15% concentration of PEG 6000 treatment was the highest tolerance limit of germination process.

Physiological response and bioaccumulation of Panax notoginseng to cadmium under hydroponic / 中国中药杂志

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.

Effect of Panax notoginseng seedlings physiological response under simulated drought stress by polyethylene glycol (PEG 6000) / 中国中药杂志

The physiological effects of Panax notoginseng seedlings under simulated drought stress by PEG 6000 on antioxidant enzymes, osmotic substances and root activities were studied. The results showed that the activity of POD and APX in roots and leaves kept rising with increasing processing concentration and time. However, on the one hand, at the same processing time, SOD in roots and leaves firstly increased and then decreased with the increase of processing concentration. On the other hand, at the same processing concentration, SOD kept rising with the extension of processing time. In addition, the activity of CAT in roots and leaves tended to increase with the increasing concentration at the same processing time, while it increased at first and then decreased with the extension of time at the same concentration. The activity of SOD and APX in stem did not change obviously, whereas CAT activity in stem increased with the increasing processing time and concentration. With the increase of processing concentration and the extension of processing time, the MDA, soluble protein, proline content and root activity in leaves and roots apparently rose. Moreover, fluorescence signal of H2O2 and NO in root tip enhanced as the processing concentration increased after treated for 1 d. In summary, P. notoginseng seedlings could deal with drought stress by means of adjusting the system of antioxidant enzyme, permeating stress substances and impeded stress signal substances. Thus, when the concentration of PEG 6000 was more than 5%, it would have harm on P. notoginseng seedlings.

Effects of stereoscopic cultivation on soil microorganism, enzyme activity and the agronomic characters of Panax notoginseng / 中国中药杂志

Compartments of soil microorganism and enzymes between stereoscopic cultivation (three storeys) and field cultivation (CK) of Panax notoginseng were carried out, and the effects on P. notoginseng agronomic characters were also studied. Results show that concentration of soil microorganism of stereoscopic cultivation was lower than field cultivation; the activity of soil urea enzyme, saccharase and neutral phosphatase increased from lower storey to upper storey; the activity of soil urea enzyme and saccharase of lower and upper storeys were significantly lower than CK; agronomic characters of stereoscopic cultivated P. notoginsengin were inferior to field cultivation, the middle storey with the best agronomic characters among the three storeys. The correlation analysis showed that fungi, actinomycetes and neutral phosphatase were significantly correlated with P. notoginseng agronomic characters; concentration of soil fungi and bacteria were significantly correlated with the soil relative water content; actinomycete and neutral phosphatase were significantly correlated with soil pH and relative water content, respectively; the activities of soil urea enzyme and saccharase were significantly correlated with the soil daily maximum temperature difference. Inconclusion, The current research shows that the imbalance of soil microorganism and the acutely changing of soil enzyme activity were the main reasons that caused the agronomic characters of stereoscopic cultivated P. notoginseng were worse than field cultivation. Thus improves the concentration of soil microorganism and enzyme activity near to field soil by improving the structure of stereoscopic cultivation is very important. And it was the direction which we are endeavoring that built better soil ecological environment for P. notoginseng of stereoscopic cultivation.

Light and temperature and their effects on photosynthesis characteristics of stereoscopic cultivation in Panax notoginseng / 中国中药杂志

Light intensity, gas temperature, soil temperature and gas exchange parameters were determined of three years old Panax notoginseng planted on different layers seedbed and different location (left, middle, right) of the same layer in greenhouse. Result show that diurnal variation of light intensity, gas temperature and soil temperature showed that upper layer > middle layer > lower layer; different locations of the same layer showed that light intensity of upper layer was not different among different locations; light intensity of middle and lower layer in right and left were the same, and significantly higher than those in the middle position; the gas temperature of each layer all with less different of each location; soil temperature of 12 cm depth is the lowest, and was gradually increased to the upper and lower surface; net photosynthetic efficiency of P. notoginseng showed that upper layer > middle layer > lower layer; there were significant correlation between soil temperature, stomatal conductance, intercellular CO2 concentration and photosynthetic rate were correlated with light intensity significantly; transpiration rates had notable correlation with light intensity and gas temperature. All above indicated that net photosynthesis rate of P. notoginseng was affected by light intensity directly, gas temperature and soil temperature indirectly. Inconclusion, stereoscopic cultivation of P. notoginseng was practicable in present study. The planting quality of P. notoginseng under stereoscopic cultivation could be improved by ameliorate the structure of seedbed to enhance the light intensity of middle and lower layer. Increase the thickness of the seedbed to decrease the temperature difference of soil. Further the management of ventilation facilities of greenhouse to control the gas temperature.

Research on output and quality of Panax notoginseng and annual change characteristics of N, P and K nutrients of planting soil under stereo-cultivation / 中国中药杂志

The output and agronomic characters of 3-year-old Panax notoginseng cultured under stereo structure (upper, middle and down layers) were investigated, and the annual change of N, P and K of its planting soil were also studied. Results showed that, compared with field cultured Panax notoginseng, growth vigour and output of stereo-cultivation were significantly lower. But the total production of the 3 layers was 1.6 times of field. The growth vigor and production of P. notoginseng was in the order of upper layer > middle layer > down layer. The content of ginsenoside in rhizome, root tuber and hair root of P. notoginseng was in the order of upper layer > field > middle layer > down layer. Organic matter content and pH of stereo-cultivation soil decreased with the prolonging of planting time, which with the same trend of yield. Organic matter content of stereo-cultivation soil was significantly higher than field, but the pH was significantly lower. Contents of total and available N, P and K in stereo-cultivation soil and field decreased with the prolonging of planting time. The content of N and P were in the order of upper layer > middle layer > yield > down layer, the content of K was in the order of upper layer > middle layer > down layer > yield. Compared with field, the proportion of N and P in the organ of underground (rhizome, root tuber and hair root) of upper layer were increased, while decreased in middle and down layers. Proportion of K in underground decreased significantly of the 3 layers. In conclusion, the agronomic characters and production of stereo-cultivation were significantly lower than that of yield. But the total production of the 3 layers were significantly higher than field of unit area. And the aim of improving land utilization efficiency was achieved. Nutritions in the soil of stereo-cultivation were enough to support the development of P. notoginseng, which was not the cause of weak growth and low production. The absorbing ability of P. notoginseng to N, P and K nutrients was decreased by stereo-cultivation mode. So, improve the growth vigour of P. notoginseng from the perspective of adjusting the stereo-cultivation mode so as to improve the nutrient absorption capacity is the future direction.

Content determination of dencichine in Panax Notoginseng by a reversed phase ion-pair chromatography / 中国中药杂志

To build a reversed phase ion-pair chromatography to determination content of Dencichine from Panax notoginseng. Using Tetrabutyl ammonium hydroxide ions by the combination of reagent and HPLC method without derivatization to test the content of dencichine directly. The optimum conditions of supersonic extraction were solid-to-liquid ratio 1: 20, Continuous ultrasonic extraction: twice, each time 15 minutes; 3,500 r · min⁻¹, then centrifuging 15 minutes. Dencichine in different age, place, part and the different Processing mode were examined. The method is simple with sound separation degree and stability, which can facilitate the determination of dencichine content directly and provide the basis in quality standard of raw material.