The characteristics of ginsenosides and oligosaccharides in mountain- and garden-cultivated ginseng.

BACKGROUND: The present study aimed to explore the chemical characteristics of mountainous forest cultivated ginseng (MFCG) and garden ginseng (GG) with respect to their ginsenosides and oligosaccharides. METHODS: A high-performance liquid chromatography with diode-array detection-evaporative light-scattering detection technique was adopted to investigate the ginseosides and oligosaccharides of GG and MFCG. RESULTS: The features of ginsenosides showed Rg1/Re in different parts of GG and MFCG: main root > lateral root > fibrous root, as well as Rg1/Re in the main root: MFCG > GG, indicating that the Rg1/Re is related to age of the ginseng. In most cases, Rg1/Re < 1 in entire GG and Rg1/Re > 1 in entire MFCG. In addition, the ratio of protopanaxadiol/protopanaxatriol in main root of GG is approximately 1 and, in the main roots of MFCG, the ratio is approximately 2 and, furthermore, Ro/Rb1 of MFCG is lower than that of GG. Analysis of oligosaccharides showed that GG mainly contained sucrose and MFCG mainly contained sucrose and maltose, and the ratio of sucrose to maltose was at least more than 4:1 in GG and less than 4:1 in MFCG in most cases, indicating the characteristics of oligosaccharides of MFCG are primarily affected by its growing environment. The results also showed that ginsenoside Re is most probably the biosynthetic precursor of ginsenoside Rg1 (i.e. Re was synthesized first and then transformed to Rg1 in vivo). CONCLUSION: The characteristics of Rg1/Re and higher maltose can be regarded as one of the characteristics of high quality MFCG, and these characteristics are related to a higher age and the cultivation environment of ginseng. The formation mechanism of these characteristics for GG and MFGG is also discussed. As far as we know, the present study is the first to determine the difference of Rg1/Re and oligosaccharides between MFCG and GG and this provides a reference for the quality control criterion of GG and MFCG. © 2020 Society of Chemical Industry.

Spaceborne limb hyperspectral imager for ozone profile detection.

A spaceborne limb hyperspectral imager for ozone detection is designed and developed. The hyperspectral imager can provide the limb hyperspectral radiances images with wide-band and large dynamic range. It is composed of an off-axis parabolic telescope and prism dispersive off-axis aspheric spectrometer, and large dynamic range detection can be realized by using a band-attenuation filter. The spectral range is from 280nm to 1000nm, the field of view is 2.4° (limb vertical direction) × 0.02° (horizontal direction), and the focal length is 69mm. The design results meet the requirements of image quality and have the characteristics of small volume and light weight, thereby making it especially suitable for the application of space remote sensing unlike existing methods that utilize complicated scanning mirror and multiple color separators. The limb hyperspectral imager is measured and calibrated on ground. It detected limb hyperspectral radiances on Tiangong-2 spacecraft of China.

A New Approach of Oil Spill Detection Using Time-Resolved LIF Combined with Parallel Factors Analysis for Laser Remote Sensing.

In hope of developing a method for oil spill detection in laser remote sensing, a series of refined and crude oil samples were investigated using time-resolved fluorescence in conjunction with parallel factors analysis (PARAFAC). The time resolved emission spectra of those investigated samples were taken by a laser remote sensing system on a laboratory basis with a detection distance of 5 m. Based on the intensity-normalized spectra, both refined and crude oil samples were well classified without overlapping, by the approach of PARAFAC with four parallel factors. Principle component analysis (PCA) has also been operated as a comparison. It turned out that PCA operated well in classification of broad oil type categories, but with severe overlapping among the crude oil samples from different oil wells. Apart from the high correct identification rate, PARAFAC has also real-time capabilities, which is an obvious advantage especially in field applications. The obtained results suggested that the approach of time-resolved fluorescence combined with PARAFAC would be potentially applicable in oil spill field detection and identification.

[Discrimination of Crude Oil Samples Using Laser-Induced Time-Resolved Fluorescence Spectroscopy].

The Laser-induced fluorescence spectra combined with pattern recognition method has been widely applied in discrimination of different spilled oil, such as diesel, gasoline, and crude oil. However, traditional three-dimension fluorescence analysis method, which is not adapted to requirement of field detection, is limited to laboratory investigatio ns. The development of oil identification method for field detection is significant to quick response and operation of oil spill. In this paper, a new method based on laser-induced time-resolved fluorescence combined with support vector machine (SVM) model was introduced to discriminate crude oil samples. In this method, time-resolved spectra data was descended into two dimensions with selecting appropriate range in time and wavelength domains respectively to form a SVM data base. It is found that the classification accurate rate increased with an appropriate selection. With a selected range from 54 to 74 ns in time domain, the classification accurate rate has been increased from 83.3% (without selection) to 88.1%. With a selected wavelength range of 387.00~608.87 nm, the classification accurate rate of suspect oil was improved from 84% (without selection) to 100%. Since the detection delay of fluorescence lidar fluctuates due to wave and platform swing, the identification method with optimizing in both time and wavelength domains could offer a better flexibility for field applications. It is hoped that the developed method could provide some useful reference with data reduction for classification of suspect crude oil in the future development.

[Characterization of Time-Resolved Laser-Induced Fluorescence from Crude Oil Samples].

To evaluate the feasibility of laser induced time-resolved fluorescence technique for in-situ detection of underwater suspended oil spill, extensive investigations have been carried out with different densities of crude oil samples from six different wells of Shengli Oilfield in this work. It was found that the fluorescence emission durations of these crude oil samples were almost the same, the Gate Pulse Delay of DDG (Digital Delay Generator) in the ICCD started at 52ns and ended at 82ns with a width (FWHM) of 10 ns. It appears that the peak location and lifetime of fluorescence for different crude oil samples varied with their densities, and those with similar densities shared a similar lifespan with the closer peak locations of fluorescence. It is also observed that the peak of fluorescence remained the same location before reaching the maximum intensity, subsequently shift to longer wavelength as fluorescence attenuated from maximum intensity with a red shift among 17-30 nm varied with samples. This demonstrated that the decay rate of fluorescent components in the crude oils was different, and energy transfer between these components might exist. It is hoped that those obtained results and characteristics could be the useful information for identification of suspended spilled-oil underwater.

[Identification of spill oil species based on low concentration synchronous fluorescence spectra and RBF neural network].

In this paper, a new method was developed to differentiate the spill oil samples. The synchronous fluorescence spectra in the lower nonlinear concentration range of 10(-2) - 10(-1) g x L(-1) were collected to get training data base. Radial basis function artificial neural network (RBF-ANN) was used to identify the samples sets, along with principal component analysis (PCA) as the feature extraction method. The recognition rate of the closely-related oil source samples is 92%. All the results demonstrated that the proposed method could identify the crude oil samples effectively by just one synchronous spectrum of the spill oil sample. The method was supposed to be very suitable to the real-time spill oil identification, and can also be easily applied to the oil logging and the analysis of other multi-PAHs or multi-fluorescent mixtures.

[Fingerprint discrimination technique of spill oil based on concentration auxiliary parameter fluorescence spectra].

In the present paper, concentration as an auxiliary parameter was introduced to the synchronous fluorescence to form concentration synchronous fluorescence matrix of the oil spill samples within the concentration range of 10(-1)-10 g x L(-1). Principal component analysis was used to classify the oil spill samples of 0# diesel, 93# gasoline and 5 crude oil simples from the Shengli oilfield. Experiments show that the introducing of concentration can reflect more composition information of the PAHs. This newly method has a better discrimination than the routine method of the synchronous fluorescence spectra obtained from spill oil samples in linear concentration range. It indicates that the spill oil samples of different type and source can be discriminated precisely, even from the same oilfield. The influence of the errors caused in the samples extraction procedure can be eliminated. All the results suggest that the technique may become a more convenient, rapid and accurate means in spill oil identification.

Comparative Analysis of Ginsenosides and Oligosaccharides in White Ginseng (WG), red Ginseng (RG) and Black Ginseng (BG).

Ginsenosides and oligosaccharides were comparatively analyzed in WG, RG and BG. The HPLC fingerprints of ginsenosides and oligosaccharides were established to unravel the characteristics of ginsenosides and oligosaccharides. The primary ginsenosides (Rg1, Rb1, Re, Rc, Rb2 and Rd, etc.) in WG were higher than those in RG and BG, but the variety of ginsenosides in RG is highest and the non-polar rare saponins are higher than RG. Five kinds of saccharides encompassed fructose, glucose, sucrose, maltose and nystose, respectively, were determined in WG, RG and BG, disclosing that, the sucrose in WG is 1.4 times of that in RG and 119.6 times of that in BG; but the maltose in RG is 25.9 times of that in WG and 3.4 times of that in BG; the fructose in BG is 44 times that in WG and 18.3 times that in RG. The chemical reactions in the processing of ginseng were elucidated. It is for the first time that the ginsenosides and oligosaccharides were compared simultaneously in WG, RG and BG.

Species identification and concentration quantification of crude oil samples in petroleum exploration using the concentration-synchronous-matrix-fluorescence spectroscopy.

In this paper, the author has developed and described a novel method for species identification and concentration quantification of crude oil sample in petroleum exploration using the concentration auxiliary parameter synchronous fluorescence technique. By introducing concentration value as a parameter, a new concentration-synchronous-matrix-fluorescence (CSMF) spectrum has been formed with a series of synchronous fluorescence spectra (SFS) at different levels of concentration. It is observed that the SFS varied with concentration level and the profiles of CSMF changed from species to species. Therefore, they can be used for species identification and concentration quantification. The CSMF of 31 crude oil samples from 20 different bore fields has been obtained to establish the database. With surface fitting, CSMF has been successfully used to discriminate the different crude oil samples from different bore fields precisely. It is also used for the quantitative analysis of concentration. Within the interesting concentration range of 10(-4)g/L to 10 g/L, the curve fitting has been used to achieve good analytical results with the relative deviation below 3%. To evaluate the practicality and efficiency of this method in field, double-blind experiments have been carried out and the relative deviation was found to be 3 times lower than by traditional fluorescence approaches. The obtained results suggest that the newly developed method may become a more specifically applicable means in petroleum exploration.