Preliminary identification of C‐terminus of trichosanthin by chemical and enzymic methods, such as hydrazinolysis, thiohydantoin reaction and carboxypeptidase hydrolysis, showed that there may be the possible presence of more than one terminus, i.e., Met and Ala but complicated by side reactions. A computer‐assisted carboxypeptidase method was first introduced by the authors to determine the C‐terminal sequence of trichosanthin, and showed that trichosanthin is heterogeneous at its C‐terminus and has two C‐terminal sequences determined as ‐Arg‐Asn‐Asn‐Met‐OH and ‐Arg‐Asn‐Asn‐Met‐Ala‐OH respectively. These results have been later unambiguously confirmed by the results from other experiments through the identification of the free alanine always present in the CNBr degradation products of trichosanthin, and the actual separation of two fragments from the finger prints as well as from the HPLC fractions of the trypsin digest of this protein. All shows that their amino acid sequences, determined by manual DABITC/PITC technique, agree well with those of the two C‐terminal sequences determined by the computer‐carboxy peptidase method.

The study on monitoring the water body range of Baiyangdian and the change of wetland information by means of remote sensing is of great significance to ensure the ecological security of Xiong’an New Area. This paper was conducted using the GF-2 remote sensing data on March and October 2018. The study was to provide an extraction model basing on NDVI-NDWI method, which compare with traditional supervised classification method. The selected sample points by using visual interpretation verified the extracted wetland information. The results show that the classification and extraction of Baiyangdian wetland information are carried out by using the model and supervised classification method respectively, and the wetland area (in which) is obtained in March. The precision of the sample points and the extracted wetland information are all above 90%, and the NDVI-NDWI method is constructed based on the NDVI-NDWI method. The extraction model is more accurate. Since the bare waters in March were 102.31 km2, 28.27 km2 more than in October; the area of aquatic plants extracted in October increased significantly from 122.57 km2 in March to 154.5 km2. It can be seen that the information of Baiyangdian wetland changes with the growth of aquatic plants. The model established by the institute can accurately extract the information of Baiyangdian wetland and provide a scientific reference for the planning and management of Xiong’an New District.