Studies On The Chemical And Biological Activity Constituents Of Four Plants

This dissertation is composed of four chapters. The first chapter included the isolation andidentification of compounds from Aeschynanthus superbus, Aeschynanthus maculatus, and Rhyncho-techum ellipticum. The second chapter studied the antioxidant, α-glucosidase inhibitory and anti-bacteriasactivity of different extracts and compounds from A.superbus, A. maculatus, and R.ellipticum werereported. The third chapter summarized the progress of landscape application, chemical constituent,pharmaceutical activity and taxonomy of the Gesneriaceae family.The four chapter studied the volatilesfrom the flowers of Clerodendron trichotomum Thunb.Chapter1. The chemical constituents of Aeschynanthus superbus, Aeschynanthusmaculatus and Rhynchotechum ellipticum.1. The chemical constituents from the A. superbus were studied by column chromatography.Twelve compounds were isolated and identified as β-sitosterol (1), lupeol (2), carissol (3),3-hydroxy-20(29)-lupen-28-oic acid (4),3β-hydroxy-5,12-oleanadien-28-oic-acid (5), apigenin (6),5,7,4’-trihydroxy-6-methoxyflavone (7), ursolic acid (8), β-daucosterol (9),2,6,-dimethyl-4-methoxy-5-hydroxy benzoic acid(10), mixture of3,24-dihdroxy-12-oleanen-28-oic acid (11) and3,24-dihdroxy-12-ursen-28-oic acid (12).Compound1~12were isolated from this plant for the first time. Compound8~12were isolated fromAeschynanthus genus for the first time. Compound2~7,10~12were isolated from this family for the firsttime. 2. The chemical constituents from the A. maculatus were studied by column chromatography.Ten compounds were isolated and identified from the A. maculatus as lupeol (1), stigmasterol (2), ursolicacid (3), stigmast-5,22(E)-diene-3β-ol (4), β-daucosterol (5),3-hydroxy-12-taraxasten-28-oic-acid (6),oleanolic acid (7),3-hydroxy-12-ursen-28-oic acid,3-O-β-D-glucopyranoside (8),3-hydroxy-12-oleanen-28-oic acid,28-O-β-D-glucopyranoside (10) and3-hydroxy-12-oleanen-28-oic acid,3-O-β-D-glucop-yranoside (11). Compound1~11were isolated from this plant for the first time. Compound6~11wasisolated from Aeschynanthus genus for the first time. Compound6~11were isolated from this family forthe first time.3. The chemical constituents from the R. ellipticum were studied by column chromatography. Sixcompounds were isolated and identified as β-sitosterol (1), ursolic acid (2), stigmasterol (3),3-hydroxy-12-oleanane-3-O-β-D-glucopyranoside (4), β-daucosterol (5) and octadecanoic acid (6). Compound1~6were isolated from this plant for the first time. And also were isolated from the Rhynchotechum Jack forthe first time.Chapter2. The biological activity of Aeschynanthus superbus, Aeschynanthus maculatus,and Rhynchotechum ellipticum.1. The inhibitory effect against α-glucosidase of different extracts and compounds from A.superbus, A. maculatus and R. ellipticum were screened in a96-well plate. Petroleum ether extracts of thethree plants and EtOAC extracts of A. maculatus and R. ellipticum showed stronger inhibitory effectagainst a-glucosidase, and were much higher than that of acarbose (IC50=1103.01μg·mL-1). Compoundslupeol, carissol,5,7,4’-trihydroxy-6-methoxyflavone, ursolic acid, stigmast-5,22(E)-diene-3β-ol,3-hydroxy -12-taraxasten-28-oic-acid and oleanolic acid also exhibited stronger inhibitory activity.2. DPPH, ABTS, and FRAP assays were used to screen the antioxidant activity of differentextracts and compounds from A. superbus, A. maculatus, and R. ellipticum. EtOAC and the MeOH extractsfrom A. superbus and A. maculatus showed better antioxidant activity.3. Antibacterial activity against Staphylococcus aureus (SA), methicillin-resistant Staphylococcusaureus (MRSA) and β-lactamase positive Staphylococcus aureus (ESBLs-SA) of total methol extracts andcompounds from A. superbus, A. maculatus and R. ellipticum were assayed. Three total methol extractsexhibited antibacterial activity of SA. The compounds displayed no activity.Chapter3. The study progress of the GesneriaceaeThe study progress of systematic taxonomy, landscape application, chemical constituent andpharmaceutical of the Gesneriaceae were summarized.Chapter4. The volatiles in the Clerodendron trichotomum Thunb.The volatiles from the flowers of Clerodendron trichotomum Thunb. were analyzed byhead-space solid micro-extraction, coupled with GC-MS for the first time.27compounds were identifiedfrom the C. trichotomum and account for94.10%of the total volatiles. Hydrocarbons, aldehydes, alcoholsand acids were dominant in the flowers. The main compounds were2,6,10,14-tetramethyl-hexadecane(17.25%), hexadecanal (10.57%),1-octen-3-ol (6.78%), benzaldehyde (6.10%) and n-hexadecanoic acid(4.85%).