Oleanane-type saponins from Lysimachia laxa Baudo and their anti-bacterial activities.

Seven new oleanane-type triterpene saponins, lysimaponins A-G, were isolated from aerial parts of Lysimachia laxa Baudo. Their chemical structures have been elucidated by analysis of spectroscopic and chemical methods. All compounds were evaluated for their anti-bacterial effects against Microcystis aeruginosa, Vibrio parahaemolyticus, V. harveyi, V. vulinificus, V. cholerae, and V. alginolyticus. All compounds showed potent anti-bacterial activities against the cyanobacteria M. aeruginosa with IC50 values ranging from 14.4 ± 1.2 to 35.3 ± 2.2 µg/mL. Compounds 1, 2, 4-7 inhibited V. parahaemolyticus with MIC values ranging from 64 to 256 µg/mL. The results suggested that saponins from L. laxa could be potential anti-cyanobacteria agents.

Chemical constituents from the heterotrophic marine microalgae Aurantiochytrium sp. SC145 and their antimicrobial activities.

One new indol, N-methoxymethyltryptophol (1), one new phenolic, (2 R)-2-(4-hydroxyphenyl)ethyl 2-hydroxy-3-phenylpropanoate (2) and fifteen known compounds (3-17) were isolated from the methanol extract of the fermentation of marine microalgae Aurantiochytrium sp. SC145. Their structures were elucidated by 1D-, 2D-NMR spectroscopic analysis, HR-ESI-MS, quantum chemical calculation methods and by comparing their NMR data with those reported in the literature. All compounds were evaluated for their antimicrobial activities against microorganisms. Compounds 2, 3 and 11 significantly exhibited antimicrobial activities on all tested Gram-(+), Gram-(-) bacteria and the yeast C. albicans with MIC values ranging from 32 to 256 µg/mL.

Acetylcholinesterase inhibition studies of alkaloid components from Crinum asiaticum var. sinicum: in vitro assessments by molecular docking and molecular dynamics simulations.

Alkaloids are among the most important and best-known secondary metabolites as sources of new drugs from medicinal plants and marine organisms. A phytochemical investigation of the whole plant of Crinum asiaticum var. sinicum resulted in the isolation of seven alkaloids (1-7), including one new dimeric compound, bis-(-)-8-demethylmaritidine (1). Their structures were elucidated using NMR and HR-ESI-MS. The absolute configuration of new compound 1 was established by circular dichroism spectroscopy. All isolated compounds were evaluated for their inhibitory effects on acetylcholinesterase (AChE) activity in vitro. Among them, compound 1 exhibited the most potent AChE inhibition. Moreover, molecular docking and molecular dynamics simulations were carried out for the most active compound to investigate their binding interactions and dynamics behavior of the AChE protein-ligand complex. Therefore, compound 1 may be a potential candidate for effectively treating Alzheimer's disease.

Chitosan membrane drafting silver-immobilized graphene oxide nanocomposite for banana preservation: Fabrication, physicochemical properties, bioactivities, and application.

In this study, silver-immobilized graphene oxide/chitosan (AGC/CTS) membranes were assembled by the solvent evaporation method, wherein Curcuma longa extract was used to synthesize silver-immobilized graphene oxide (AGC) nanocomposite. The characterization results showed that the AGC was successfully synthesized with AgNPs distributed quite evenly on GO sheets. The as-prepared AGC also exhibited high antibacterial activity and low cytotoxicity towards normal cell lines compared to human epithelial carcinoma cell lines. Besides, the fabrication of AGC/CTS membranes was additionally assessed with different AGC ratios and thicknesses. The results revealed the membrane containing 3 wt% of AGC with great hygroscopicity and elastic modulus of 27.03 ± 3.07 MPa. The samples also performed excellent bactericidal capability, along with good mechanical properties for banana preservation. Therewithal, the membrane-coated bananas were also elucidated to ripen at slower paces and less damage, with no appearance of patches of mold on the banana peel surface, eventually prolonging the shelf life of bananas up to 10 days as compared to the non-coated ones. The aforesaid results confirm the potential application of the AGC/CTS membrane as a safe and alternative fruit preservation agent in the food industry.

Atractylodes macrocephala Rhizomes Contain Anti-inflammatory Sesquiterpenes.

Two new compounds, named eudesm-4(15),7-diene-3α,9ß,11-triol (1) and eudesm-4(15),7-diene-1ß,3α,9ß,11-tetraol (2) together with three known sesquiterpene lactones (1S,5R,7R,10R)-secoatractylolactone (3), (1S,5R,7R,10R)-secoatractylolactone-11-O-ß-D-glucopyranoside (4) atractylenolide III (5) were isolated from the rhizomes of Atractylodes macrocephala. Their structures were elucidated by using one-dimensional (1D) and 2D-NMR spectra and high resolution electrospray ionization (HR-ESI)-MS data. Compound 5 exhibited the most active anti-inflammatory activity with IC50 values of 27.5 µM in inhibiting of nitric oxide production. Compounds 1, 2, and 3 showed moderate effects while compound 4 was inactive.

Mussel - Inspired biosorbent combined with graphene oxide for removal of organic pollutants from aqueous solutions.

In this work, we develop a mussel-inspired biosorbent combined with graphene oxide for removal of organic dyes in water sources. The composite was prepared via self-polymerization of dopamine in weak alkaline solution containing graphene oxide at ambient condition. Morphological and structural studies revealed that polydopamine has gradually grown to cover the surface of graphene oxide flakes, partially reduced these flakes, and somehow form many grains (size around 20 nm) on the flakes instead of making very large aggregates as usual. The mass ratio between two components of the composite was also investigated to find the optimal one which provides enough surface area (20 m2.g-1) and maintain adhesive sites in order to ensure high-efficiency removal of organic molecules. The adsorption kinetics and isotherms of as-prepared adsorbent towards methylene blue were found to fit well with pseudo-first order kinetics model and Langmuir isotherm. The maximum adsorption capacity (qm) and Langmuir constant (kL) were estimated to be 270 mg.g-1 and 0.49 L. mg-1. The as-prepared bio-sorbent is very promising for remediation of water sources contaminated with cationic organic molecules and heavy metal ions.

Undescribed chalcone and stilbene constituents from Lysimachia baviensis and their anti-inflammatory effect.

The chemical composition and anti-inflammatory activity of the endemic Lysimachia baviensis were investigated for the first time in this study. A phytochemical fractionation of the methanol extract of L. baviensis resulted in the isolation of a new stilbene (bavienside A, 1) and two new chalcone glycosides (baviensides B and C, 2 and 3). Their structures were elucidated via the interpretation of NMR and HRESIMS spectroscopic data. Compounds 1-3 strongly inhibited the production of nitric oxide in LPS-induced RAW264.7 cells with the IC50 values of 6.23, 2.86 and 3.51 µM, respectively. The C-acetylstilbene and carbomethyl chalcone structures in compound 1 and 3 were found for the first time from natural source and could be important markers for chemotaxonomy of Lysimachia baviensis.

Pattern and perceived changes in quality of life of Vietnamese medical and nursing students during the COVID-19 pandemic.

BACKGROUND: The COVID-19 pandemic and governments' response lead to dramatical change in quality of life worldwide. However, the extent of this change in Vietnamese medical and nursing students has not been documented. OBJECTIVES: The study aims to describe the quality of life and changes in quality of life of medical and nursing students during the COVID-19 pandemic and examine the association of quality of life and changes in quality of life with fear of COVID-19 and other socio-economic and demographic factors. METHODS: The study was a cross-sectional study on all students of Hanoi Medical University from 3 majors: General Medicine, Preventive Medicine, Nursing (3672 invited students); from 7th to 29th of April 2020; using an online questionnaire that included demographic and academic information, the Vietnamese version of the SF-36 Quality of Life questionnaire and the Fear of COVID-19 Scale (FCV-19S). Linear and modified Poisson regression was used to examine the association between quality of life, changes in quality of life and other factors. RESULTS: The number of participants was 1583 (response rate 43%). Among 8 dimensions of the SF-36 (ranged 0-100), Vitality had the lowest score with a median score of 46. The median physical composite score (PCS) of the sample was 40.6 (IQR:20.8-53.2), 33.5% of the sample had an above-population average PCS score. The median mental composite score (MCS) of the sample was 20.3 (IQR:3.8-31.7), and 98.2% had an MCS score below average. 9.9% (95%CI:8.5%-11.4%) of the population reported a significant negative change in the quality of life. Fear of COVID-19 was not associated with significant changes in quality of life, nor MCS while having some association with PCS (Coef:-5.39;95%CI:-3to-7.8). Perceived reduction in quality of life was also associated with: being on clinical rotation COVID-19 (PR:1.5;95%CI:1.05-2.2), difficulties affording health services (PR:1.4;95%CI:1.02-1.95), obesity (PR:2.38;95%CI:1.08-5.25) and chronic disease (PR:1.92;95%CI:1.23-3), typical symptoms (PR:1.85; 95%CI:1.23-2.78) and atypical symptoms of COVID-19 (PR:2.32;95%CI:1.41-3.81). CONCLUSION: The majority of medical and nursing students had below average quality of life, with lower vitality and mental composite health score in the settings of COVID-19. Perceived decrease in quality of life was associated with clinical rotation, difficulties affording healthcare services and was not associated with Fear of COVID-19.

Laparoscopic Surgery for Intestinal Obstruction Caused by an Internal Paracecal Hernia.

Paracecal hernia is rarely associated with ischemia and has seldom been reported in the few published studies in the review literature. We present a case of incarcerated paracecal hernia with intestinal obstruction that was effectively treated with laparoscopic intervention. A 64-year-old woman who had not previously undergone any intestinal surgery arrived complaining of abdominal pain and vomiting at our hospital. Abdominal computed tomography suggested intestinal obstruction. A laparoscopic emergency procedure demonstrated an incarcerated small bowel loop in the paracecal region. The confined small bowel was removed from the paracecal area. On the fourth postoperative day, the patient was discharged. This case is unusual because the patient presented with small bowel strangulation, leading to intestinal obstruction. Laparoscopic surgery is beneficial for diagnosing internal hernias and curing small-bowel obstructions caused by paracecal hernias.

Penicillium digitatum as a Model Fungus for Detecting Antifungal Activity of Botanicals: An Evaluation on Vietnamese Medicinal Plant Extracts.

Medicinal plants play important roles in traditional medicine, and numerous compounds among them have been recognized for their antimicrobial activity. However, little is known about the potential of Vietnamese medicinal plants for antifungal activity. In this study, we examined the antagonistic activity of twelve medicinal plant species collected in Northern Vietnam against Penicillium digitatum, Aspergillus flavus, Aspergillus fumigatus, and Candida albicans. The results showed that the antifungal activities of the crude extracts from Mahonia bealei, Ficus semicordata, and Gnetum montanum were clearly detected with the citrus postharvest pathogen P. digitatum. These extracts could fully inhibit the growth of P. digitatum on the agar medium, and on the infected citrus fruits at concentrations of 300-1000 µg/mL. Meanwhile, the other tested fungi were less sensitive to the antagonistic activity of the plant extracts. In particular, we found that the ethanolic extract of M. bealei displayed a broad-spectrum antifungal activity against all four pathogenic fungi. Analysis of this crude extract by enrichment coupled with high-performance liquid chromatography revealed that berberine and palmatine are major metabolites. Additional inspections indicated berberine as the key compound responsible for the antifungal activity of the M. bealei ethanolic extract. Our study provides a better understanding of the potential of Vietnamese medicinal plant resources for combating fungal pathogens. This work also highlights that the citrus pathogen P. digitatum can be employed as a model fungus for screening the antifungal activity of botanicals.

Steroid glycosides isolated from Paris polyphylla var. chinensis aerial parts and paris saponin II induces G1/S-phase MCF-7 cell cycle arrest.

In our previous research on Vietnamese medicinal plants, we found that the ethanolic extract of the aerial parts of Paris polyphylla var. chinensis exhibited cytotoxic effects in vitro in the MCF-7 human cancer cell line. Here, we used combined chromatographic separations to isolate six compounds including a new steroid glycoside, paripoloside A (3), and five known compounds, from the butanol extract of the aerial parts of P. polyphylla. We unambiguously elucidated their structures based on spectroscopic data (proton and carbon-13 nuclear magnetic resonance, heteronuclear single quantum coherence, heteronuclear multiple bond correlation, correlation spectroscopy, and high-resolution electrospray ionization mass spectroscopy data), and chemical reactions. Among the isolated compounds, paris saponin II (PSII) had the strongest cytotoxic effects against MCF-7 breast cancer cells. Interestingly, PSII significantly increased the expression of p53, p21, p27, and Bax protein levels and significantly suppressed the expression of cyclin D1 and retinoblastoma protein. These data suggest that PSII may induce G1/S phase cell cycle arrest and apoptosis pathway development in MCF-7 cells. Furthermore, the MCF-7 breast cancer cells mechanism of PSII was also investigated using molecular docking. Together, our results demonstrate that isolated compounds from P. polyphylla are promising candidates as breast cancer inhibitors.

Metabolomics Approach for Discrimination and Quality Control of Natural and Commercial Fallopia multiflora Products in Vietnam.

A precise HPLC-DAD-based quantification together with the metabolomics statistical method was developed to distinguish and control the quality of Fallopia multiflora, a popular medicinal material in Vietnam. Multivariate statistical methods such as hierarchical clustering analysis and principal component analysis were utilized to compare and discriminate six natural and twelve commercial samples. 2,3,4',5-Tetrahydroxystilbene 2-O-ß-D-glucopyranoside (THSG) (1), emodin (4), and the new compound 6-hydroxymusizin 8-O-α-D-apiofuranosyl-(1⟶6)-ß-D-glucopyranoside (5) could be considered as important markers for classification of F. multiflora. Furthermore, seven phenolics were quantified that the variation in the contents of selected metabolites revealed the differences in the quality of natural and commercial samples. Recovery of the compounds from the analytes was more than 98%, while the limits of detection (LOD) and the limits of quantitation (LOQ) ranged from 0.5 to 6.6 µg/ml and 1.5 to 19.8 µg/ml, respectively. The linearity, LOD, LOQ, precision, and accuracy satisfied the criteria FDA guidance on bioanalytical methods. Overall, this method is a promising tool for discrimination and quality assurance of F. multiflora products.

Quality of life among newly admitted patients to cancer hospital in Vietnam and associated factors.

A cross-sectional study was conducted among 262 newly admitted patients of a cancer hospital in Vietnam. The Vietnamese version EORTC-30 questionnaire 3.0 was used to interviews patients during the first week after their admission. Lower global quality of life and physical functioning scores were significantly associated with older age, lung and gastrointestinal cancers. Emotional functioning score was lower among female patients as compared to males. Financial difficulty was an important preditor for almost all functional scales. Management of early symptoms, providing early emotional supports and appropriate policies to reduce financial difficulty are important to improve cancer patients' quality of life.

Essential Oils of Lemongrass (Cymbopogon citratus Stapf) Induces Apoptosis and Cell Cycle Arrest in A549 Lung Cancer Cells.

Essential oils were extracted from the culm and leaf of Cymbopogon citratus collected from different regions of Vietnam and analyzed using GC/MS. The results showed that citral is the major component accounting for 61.20%-76.46% of the essential oils. The citral content was higher in the essential oil obtained from the leaf than in that from the culm of lemongrass in all regions. In particular, camphene, valerianol, and epi-α-muurolol can be used to differentiate essential oils originating from leaves versus culms. The cytotoxic effects of the essential oils on various lung cancer cell lines were evaluated in the present study. All essential oils exhibited cytotoxicity in the tested cells. The Ha Loc leaf essential oil (HLL) exhibited the most potent effects on A549 and H1975 cells, with IC50 values of 1.73 ± 0.37 and 4.01 ± 0.30 µg/mL, respectively. The Hy Cuong leaf essential oil (HCL) showed the strongest effect on H1299 cells, with an IC50 value of 2.45 ± 0.21 µg/mL. The Kim Duc culm (KDC) essential oil exerted the strongest cytotoxic effects against H1650 cells, with an IC50 value of 4.86 ± 0.29 µg/mL. The HLL induced apoptosis and cycle arrest in A549 cells according to flow cytometric analysis and fluorescent nuclear staining assays. The western blot analysis indicated that HLL induced the apoptotic effect by altering the regulating proteins of the apoptosis process such as caspase-3, Bcl-2, and Bax. The data strongly suggested that the intrinsic pathway may play an important role in the apoptotic effects of HLL.

Distribution and density of Lutraria rhynchaena Jonas, 1844 relate to sediment while reproduction shows multiple peaks per year in Cat Ba-Ha Long Bay, Vietnam.

Lutraria rhynchaena Jonas, 1844 is of great commercial interest, but its reserves have dramatically declined over recent decades. Therefore, there is an urgent need of scientific basis to propose effective fishery management measures and improve artificial aquaculture of the clam. In this study, we investigated the distribution and density of L. rhynchaena, sediment characteristics, and established the clam's reproductive cycle through monthly observations from August 2017 to July 2018. The study results showed that distribution and density of clams are related to sediment types, and the sediment type of medium sand is likely the best benthic substrate for the clams. The spawning of clams occurred throughout the year with three spawning peaks in January, April and September. For the sustainable management of the clam resource in Cat Ba-Ha Long Bay, the fishery authorities can issue a ban on harvest of the clam in spawning peak months in January, April and September.

Ethanol extract of Polyscias fruticosa leaves suppresses RANKL-mediated osteoclastogenesis in vitro and LPS-induced bone loss in vivo.

BACKGROUND: Many bone-related diseases such as osteoporosis and rheumatoid arthritis are commonly associated with the excessive activity of osteoclasts. Polyscias fruticosa has been used as traditional medicine for the treatment of ischemia and inflammation and also eaten as a salad. However, its effect on the bone related diseases has not been investigated yet. PURPOSE: This study aimed to investigate the effect of ethanol extract of P. fruticosa on RANKL-induced osteoclastogenesis in vitro and LPS-induced bone loss in mouse, and evaluate anti-osteoclastogenic activities of its major constituents. METHODS: BMMs or RAW264.7 cells were treated with ethanol extract from P. fruticose leaves (EEPL), followed by an evaluation of cell viability, RANKL-induced osteoclast differentiation, actin-ring formation, and resorption pits activity. Effects of EEPL on RANKL-induced phosphorylation of MAPKs were evaluated by Western blotting. The expression levels of NFATc1 and c-Fos were evaluated by Western blotting or immunofluorescence assay. The expression levels of osteoclast-specific marker genes were evaluated by Western blotting and reverse transcription-qPCR analysis. A LPS-induced murine bone loss model was used to evaluate the protective effect of EEPL on inflammation-induced bone loss. HPLC analysis was performed to identify the major constituents of EEPL. RESULTS: EEPL significantly inhibited RANKL-induced osteoclast differentiation by decreasing the number of osteoclasts, osteoclast actin-ring formation, and bone resorption. EEPL suppressed RANKL-induced phosphorylation of p38 and JNK MAPKs, as well as the expression of c-Fos and NFATc1. EEPL decreased the expression levels of osteoclast marker genes, including MMP-9, TRAP and CtsK. Mice treated with EEPL significantly protected the mice from LPS-induced osteoclast formation and bone destruction as indicated by micro-CT and histological analysis of femurs. We also identified 3-O-[ß-d-glucopyranosyl-(1→4)-ß-d-glucuronopyranosyl] oleanolic acid 28-O-ß-d-glucopyranosyl ester (1) and quercitrin (3) as the active constituents in EEPL for inhibiting RANKL-induced osteoclast differentiation. CONCLUSION: The results showed that EEPL exerted anti-osteoclastogenic activity in vitro and in vivo by inhibiting RANKL-induced osteoclast differentiation and function, and suggested that EEPL could have beneficial applications for preventing or inhibiting osteoclast-mediated bone diseases.

Wedtrilosides A and B, two new diterpenoid glycosides from the leaves of Wedelia trilobata (L.) Hitchc. with α-amylase and α-glucosidase inhibitory activities.

In the ongoing research to find new diabetes constituents from the genus Wedelia, the chemical constituent of Wedelia trilobata leaves, a Vietnamese medicinal plant species used to treat type 2 diabetes mellitus, was selected for detailed investigation. From a methanolic extract, two new ent-kaurane diterpenoids, wedtrilosides A and B (1 and 2), along with five known metabolites (3-7), were isolated from W. trilobata. The chemical structures of (1-7) were assigned via spectroscopic techniques (IR, 1D, 2D NMR and HR-QTOF-MS data) and chemical methods. The isolates were evaluated for α-amylase and α-glucosidase inhibitory activities compared to the clinical drug acarbose. Among them, compounds 4, 6, and 7 showed the most potent against α-glucosidase enzyme with IC50 values of 27.54 ±â€¯1.12, 173.78 ±â€¯2.37, and 190.40 ±â€¯2.01 µg/mL. While moderate inhibitory effect against α-amylase was observed with compounds 6 and 7 (with IC50 = 181.97 ±â€¯2.62 and 52.08 ±â€¯0.56 µg/mL, respectively). The results suggested that the antidiabetic properties from the leaves of W. trilobata are not simply a result of each isolated compound, but are due to other factors such as the accessibility of polyphenolic groups to α-amylase and α-glucosidase activities.

Ganomycin I from Ganoderma lucidum attenuates RANKL-mediated osteoclastogenesis by inhibiting MAPKs and NFATc1.

BACKGROUND: Many bone-related diseases such as osteoporosis and rheumatoid arthritis are commonly associated with excessive activity of the osteoclast. Ganomycin I (GMI), a meroterpenoid isolated from Vietnamese mushroom Ganoderma lucidum, possesses a variety of beneficial effects on human health. However, its impact and underlying mechanism on osteoclastogenesis remain unclear. In the present study, we investigated the effect of GMI on RANKL-induced osteoclast formation in mouse BMMs and RAW264.7 cells. METHODS: BMMs or RAW264.7 cells were treated with GMI followed by an evaluation of cell viability, RANKL-induced osteoclast differentiation, actin-ring formation, and resorption pits activity. Effects of GMI on RANKL-induced phosphorylation of MAPKs as well as the expression levels of NFATc1 and c-Fos were evaluated by Western blot analysis. Expression levels of osteoclast marker genes were evaluated by Western blot analysis and reverse transcription-qPCR. RESULTS: GMI significantly inhibited RANKL-induced osteoclast differentiation by decreasing the number of osteoclasts, osteoclast actin-ring formation, and bone resorption in a dose-dependent manner without affecting cell viability. At molecular level, GMI inhibited the RANKL-induced phosphorylation of ERK, JNK, and p38 MAPKs, as well as the expression levels of c-Fos and NFATc1, which are known to be crucial transcription factors for osteoclast formation. In addition, GMI decreased expression levels of osteoclastogenesis specific marker genes including c-Src, CtsK, TRAP, MMP-9, OSCAR, and DC-STAMP in RANKL-stimulated BMMs. CONCLUSION: Our findings suggest that GMI can attenuate osteoclast formation by suppressing RANKL-mediated MAPKs and NFATc1 signaling pathways and the anti-osteoclastogenic activity of GMI may extend our understanding of molecular mechanisms underlying biological activities and pharmacological use of G. lucidum as a traditional anti-osteoporotic medicine.

Hypoglycemic property of triterpenoid saponin PFS isolated from Polyscias fruticosa leaves.

This paper evaluated the inhibitory effect of 3-O-[ß-d-glucopyranosyl-(1→4)-ß-d-glucuronopyranosyl] oleanolic acid 28-O-ß-d-glucopyranosyl ester (PFS), a major saponin isolated from Polyscias fruticosa leaves, on α-amylase and α-glucosidase, and its potential for reducing the postprandial blood glucose level in mice. In enzyme inhibition assays, PFS strongly inhibited porcine pancreas α-amylase and yeast α-glucosidase. Using the Lineweaver-Burk equation, we found that PFS inhibited porcine pancreas α-amylase in a mixed noncompetitive mode, and yeast α-glucosidase via noncompetitive inhibition. In the sucrose tolerance test, PFS at 100 mg/kg body weight significantly decreased the postprandial blood glucose level in mice fed a high-sucrose diet. These findings suggest that P. fruticosa leaves and their major saponin PFS can be used to prevent and treat diabetes and its complications.

α-Amylase and α-Glucosidase Inhibitory Activities of Chemical Constituents from Wedelia chinensis (Osbeck.) Merr. Leaves.

As part of an ongoing search for new natural products from medicinal plants to treat type 2 diabetes, two new compounds, a megastigmane sesquiterpenoid sulfonic acid (1) and a new cyclohexylethanoid derivative (2), and seven related known compounds (3-9) were isolated from the leaves of Wedelia chinensis (Osbeck.) Merr. The structures of the compounds were conducted via interpretation of their spectroscopic data (1D and 2D NMR, IR, and MS), and the absolute configurations of compound 1 were determined by the modified Mosher's method. The MeOH extract of W. chinensis was found to inhibit α-amylase and α-glucosidase inhibitory activities as well as by the compounds isolated from this extract. Furthermore, compound 7 showed the strongest effect with IC50 values of 112.8 ± 15.1 µg/mL (against α-amylase) and 785.9 ± 12.7 µg/mL (against α-glucosidase). Compounds 1, 8, and 9 showed moderate α-amylase and α-glucosidase inhibitory effects. Other compounds showed weak or did not show any effect on both enzymes. The results suggested that the antidiabetic properties from the leaves of W. chinensis are not simply a result of each isolated compound but are due to other components such as the accessibility of polyphenolic groups to α-amylase and α-glucosidase activities.