Sin-Min Li

Prof. Dr. Sin-Min Li

School of Pharmacy, Kaohsiung Medical University, Kaohsiung City, Taiwan
orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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24 December 2024 in Antioxidants
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Journal Article
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CTChia-Hsuan Tsai
Chia-Hsuan Tsai
YLYa-Lun Liou
Ya-Lun Liou
Sin-Min LiSin-Min Li
Sin-Min Li
HLHsiang-Ruei Liao
Hsiang-Ruei Liao
Jih-Jung ChenJih-Jung Chen
Jih-Jung Chen
Rhamnus formosana is a creeping evergreen shrub endemic to Taiwan. In traditional medicine, Rhamnaceae plants are used as herbal remedies for conditions such as itching, difficulty urinating, and constipation. This study explores the inhibitory effects of various solvent extracts and bioactive components of R. formosana on α-glucosidase, tyrosinase, acetylcholinesterase (AChE), and antioxidant activity. The 100 °C water extract exhibited strong antioxidant activity in DPPH, ABTS, superoxide, and FRAP assays. The methanol extract demonstrated the highest α-glucosidase inhibitory effect, while the ethanol extract displayed potent AChE inhibition and the acetone extract showed the most potential tyrosinase inhibitory activity among the extracts. Five main biocomponents were isolated and evaluated for their bioactivities. Among them, kaempferol (1) and quercetin (2) exhibited notable antioxidant activity in DPPH and ABTS assays. Particularly, kaempferol (1) performed the best α-glucosidase inhibitory effect, physcion (5) showed the strongest AChE inhibition, and quercetin (2) demonstrated the most potential for tyrosinase inhibitory activity. Further molecular docking studies revealed that there may be stronger binding mechanisms between bioactive components and target enzymes (including α-glucosidase, acetylcholinesterase, and tyrosinase) than the positive control. These findings suggest that bioactive extracts and compounds from the stems of R. formosana may have potential as natural antioxidant, anti-α-glucosidase, anti-AChE, and anti-tyrosinase drug candidates or dietary supplements for the management of oxidative stress-related conditions, including hyperglycemia, pigmentation disorders, and neurodegenerative diseases.

13 May 2021 in Molecules
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CCCheng-Yen Chung
Cheng-Yen Chung
CTChing-Chun Tseng
Ching-Chun Tseng
Sin-Min LiSin-Min Li
Sin-Min Li
STShuo-En Tsai
Shuo-En Tsai
HLHui-Yi Lin
Hui-Yi Lin
FWFung Fuh Wong
Fung Fuh Wong
N-Aminophthalimides and phthalazine 1,4-diones were synthesized from isobenzofuran-1,3-dione, isoindoline-1,3-dione, furo [3,4-b] pyrazine-5,7-dione, or 1H-pyrrolo [3,4-c] pyridine-1,3-dione with monohydrate hydrazine to carry out the 5-exo or 6-endo nitrogen cyclization under the different reaction conditions. Based on the control experimental results, 6-endo thermodynamic hydrohydrazination and kinetical 5-exo cyclization reactions were individually selective formation. Subsequently, Vilsmeier amidination derivatization was successfully developed to probe the structural divergence between N-aminophthalimide 2 and phthalazine 1,4-dione 3. On the other hand, the best tautomerization of N-aminophthalimide to diazinone was also determined under acetic acid mediated solution.

29 March 2025 in Antioxidants
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PKPao-Jen Kuo
Pao-Jen Kuo
LCLi-Ting Chen
Li-Ting Chen
Sin-Min LiSin-Min Li
Sin-Min Li
ZCZih-Rong Chen
Zih-Rong Chen
Jih-Jung ChenJih-Jung Chen
Jih-Jung Chen
Leaves of Eriobotrya japonica have long been utilized in traditional Chinese medicine (TCM) for treating pulmonary inflammation and stomach disorders. This study extends their pharmacological applications by evaluating the antioxidant, anti-α-glucosidase, anti-acetylcholinesterase (AChE), and anti-inflammatory activities of solvent extracts and isolated bioactive components through an integrative approach combining extraction, bioassays, and molecular docking. Solvent extracts prepared with varying polarities exhibited distinct bioactivities, with the 100 °C water and methanol extracts displaying the strongest antioxidant potential. The ethyl acetate extract exhibited potent α-glucosidase inhibition, whereas the n-hexane extract demonstrated significant AChE inhibitory activity. Among the isolated compounds, epicatechin (5) (SC50 = 7.83 ± 0.34 μM) and rutin (6) (SC50 = 6.69 ± 0.25 μM) showed superior ABTS and superoxide scavenging activities, respectively, compared to the positive controls (BHT and cynaroside). Ursolic acid (2) exhibited stronger α-glucosidase inhibition (IC50 = 10.68 ± 0.76 μM) than acarbose (IC50 = 419.93 ± 29.15 μM), while tormentic acid (4) demonstrated superior AChE inhibition compared to chlorogenic acid. Ursolic acid (2) also displayed NO inhibition (IC50 = 20.18 ± 1.46 μM) comparable to quercetin (IC50 = 17.05 ± 1.63 μM), with Western blot analysis confirming its potent iNOS inhibitory activity. Molecular docking further supported these findings, revealing that ursolic acid (2) exhibited stronger binding affinity to α-glucosidase (−8.7 kcal/mol) than acarbose (−5.1 kcal/mol), tormentic acid (4) displayed higher binding energy to AChE (−8.8 kcal/mol) compared to chlorogenic acid (−7.8 kcal/mol), and ursolic acid (2) (−7.5 kcal/mol) showed a binding affinity to iNOS similar to that of quercetin (−7.7 kcal/mol). These results highlight the strong potential of E. japonica leaf extracts and bioactive compounds as natural antioxidants, enzyme inhibitors, and anti-inflammatory agents, supporting their development as dietary supplements or therapeutic candidates for managing oxidative stress, hyperglycemia, neurodegenerative diseases, and inflammatory disorders.

19 January 2026 in Antioxidants
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CYCheng-Shin Yang
Cheng-Shin Yang
Sin-Min LiSin-Min Li
Sin-Min Li
Jih-Jung ChenJih-Jung Chen
Jih-Jung Chen
Mangosteen (Garcinia mangostana L.) has long been used in traditional Southeast Asian medicine to treat inflammatory-related conditions. In this study, three new compounds, including garcimangone A (1), garcimangone B (2), and the S-form of garcimangone C (3), and 18 known compounds were isolated and investigated for their anti-inflammatory properties and effects on M1- and M2-associated markers. Among the isolated components, γ-mangostin (5), garcinone D (6), morusignin J (15), and fuscaxanthone C (16) showed the most potent NO-inhibitory effects in LPS-stimulated RAW264.7 cells. SAR study revealed that chromeno moiety at C-3,4, oxygen substituents at C-1,3,6,7, and isoprenyl groups at C-2,8 are key structural features that promoted anti-inflammatory activity. Cytokine analysis results indicated that morusignin J (15) and fuscaxanthone C (16) could modulate the production of pro-inflammatory cytokines, such as TNF-α and IL-6, while modulating the anti-inflammatory cytokine IL-10. Western blot results demonstrated that morusignin J (15) modulated the inflammatory response through NF-κB and MAPK signaling and increased the expression of M2-associated markers KLF4 and arginase-1 in LPS-induced RAW264.7 macrophages. Further molecular docking analysis confirmed the high binding affinity of morusignin J (15) with key iNOS residues, such as Gln257, Pro344, Glu371, and Hem901, and the in silico prediction supported its potent oral bioavailability and drug-likeness. These in vitro and in silico findings highlight that pericarps of G. mangostana possess potential as promising natural sources for functional extracts and bioactive constituents for the development of antioxidative and anti-inflammatory candidates, and warrant further in vivo investigation in the future.

12 January 2026 in Antioxidants
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SCShih-Jung Cheng
Shih-Jung Cheng
Yuen-Sing LeeYuen-Sing Lee
Yuen-Sing Lee
LCLin-Yang Cheng
Lin-Yang Cheng
Sin-Min LiSin-Min Li
Sin-Min Li
Jih-Jung ChenJih-Jung Chen
Jih-Jung Chen
Oxidative stress is a key driver of chronic inflammatory diseases. Anodendron affine is a native Formosan plant species in Taiwan that remains largely underexplored phytochemically and bioactivity. To reveal the bioactive constituents and assess its potential as a source of anti-inflammatory antioxidants, we performed bioactivity-guided fractionation and evaluated the inhibition of superoxide anion (O2•−) generation in formyl-L-methionyl-L-leucyl-L-phenylalanine-stimulated human neutrophils. Molecular docking simulations were employed to model interactions with Formyl peptide receptor 1 (FPR1) and the Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex, including neutrophil cytosol factor 1 (p47phox) and NADPH oxidase 2 (NOX2), to propose a theoretical mechanism of action. Phytochemical investigation led to the isolation of two new compounds, methyl 4,5-O-diferuloyl-3-methoxyquinate (1) and 16-pregnen-3,12,20-trione (2), together with four known compounds. Notably, 4-hydroxy-3-prenylbenzoic acid (5) exhibited potent inhibitory activity (IC50 = 17.65 ± 0.97 μM), surpassing the activity of the positive control, ibuprofen (IC50 = 27.85 ± 3.56 μM). Docking studies suggested that anodendrosin H (4) and 4-hydroxy-3-prenylbenzoic acid (5) exhibit high predicted binding affinity to p47phox and NOX2. Based on these results, compounds 1, 4, and 5 from A. affine were identified as potential lead candidates for the development of novel anti-inflammatory therapeutics.

29 July 2026 in Antioxidants
Verified
Journal Article
Open access
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Yuen-Sing LeeYuen-Sing Lee
Yuen-Sing Lee
Sin-Min LiSin-Min Li
Sin-Min Li
HCHui-Ju Chen
Hui-Ju Chen
Jih-Jung ChenJih-Jung Chen
Jih-Jung Chen
This study investigated the extracts and bioactive constituents of the aerial parts of Polygonum aviculare L., a well-known traditional medicine for inflammation and diuresis, through bioactivity-guided investigation and molecular docking analysis. Solvent extracts demonstrated significant antioxidant, anti-α-glucosidase, and anti-inflammatory activities, supporting their value for further pharmacological investigation. Among the isolated compounds, gallic acid (1), quercetin (3), myricetin (4), avicularin (6), and isorhamnetin (7) exhibited excellent antioxidant activity in the DPPH assay (SC50 ≤ 6.50 μM) and were stronger than the positive control BHT (SC50 = 36.99 μM). Kaempferol (9) (IC50 of 4.50 µM) demonstrated the highest α-glucosidase inhibition, surpassing that of the clinically used acarbose (IC50 = 519.7 µM). Additionally, gallic acid and quercetin demonstrated significantly stronger NO inhibition than apigenin, while kaempferol showed comparable activity (IC50 = 15.06 ± 1.50 μM vs. 16.08 ± 1.86 μM for apigenin). Molecular docking analyses supported favorable interactions between the active compounds and α-glucosidase and inducible nitric oxide synthase (iNOS). Kaempferol reduced the expression of iNOS and COX-2 in LPS-stimulated RAW 264.7 macrophages and was associated with increased KLF4 and Arg-1 expression and decreased phosphorylation of p38 MAPK and IκBα, suggesting a potential role in promoting an anti-inflammatory M2-like macrophage phenotype. Structure–activity relationship analysis indicated that flavonoid aglycones and specific hydroxylation patterns contribute to the observed biological activities. Collectively, these findings identify quercetin and kaempferol as highly active constituents of P. aviculare and support their potential for further pharmacological investigation.