Development and Validation of an HPLC-DAD Method for Simultaneous Quantitation of Steppogenin and Flavonoids from the Stems of Morus alba

Morus alba L. is well-known for its medicinal and economic value, particularly in Asian countries. Among the isolated compounds from this plant, steppogenin is exhibited as a flavonoid with promising pharmacological properties. This study focused on isolating bioactive compounds, notably steppogenin, from the ethyl acetate extract of M. alba. Additionally, a high-performance liquid chromatography-diode array detector (HPLC-DAD) method for the simultaneous quantification of steppogenin and isolated compounds was developed and validated. The calibration curve showed excellent linearity, with a correlation coefficient (R 2 ) value greater than 0.9957. The limit of detection (LOD) ranged from 0.006 to 0.018 μg/mL, whereas the limit of quantification (LOQ) ranged from 0.020 to 0.061 μg/mL. In precision tests conducted intra-day and inter-day, the accuracy was between 97.32% and 106.39%, with relative standard deviations (RSD) less than 2.27% and 1.65%, respectively. The presence of steppogenin and other flavonoids was confirmed by the study, contributing to the understanding of the chemical composition of M. alba. This validated analytical method offers a reliable means of quantifying steppogenin and aiding future research into its therapeutic potential.

Cytotoxic Activities on Human Ovarian Cancer Cell Lines by Neolignans and Diarylnonanoids from the Seed of Myristica fragrans Houtt

Ovarian cancer is a primary global health concern, often diagnosed at advanced stages with limited treatment options and poor prognosis. Natural products have emerged as potential sources of safe and effective therapies. From the seeds of Myristica fragrans Houtt. (nutmeg), 24 compounds, including neolignans and diarylnonanoid derivatives, were isolated and structurally elucidated. The cytotoxic activities of these isolated metabolites against cisplatin-sensitive and resistant human ovarian cancer cell lines were evaluated. In particular, myrifragranone C (23) exhibited cytotoxicity against all test cancer cell lines A2780, TOV-112D, and SK-OV3 with IC50 values of 14.1, 16.9, and 33.4 μM, respectively. Furthermore, compound 23 induced the death of A2780 and SK-OV3 cancer cells via apoptosis. Western blotting revealed that compound 23 significantly increased the expression of cleaved caspase-3 and poly-ADP ribose polymerase and promoted apoptosis via the mitogenactivated protein kinase signaling pathway. Our findings may provide a preliminary understanding of the antiovarian cancer effect of the active compound myrifragranone C as a potential treatment using natural products.

Inhibition of α-Glucosidase by Abietane-Type Diterpenoids Isolated from Roots of Salvia miltiorrhiza

Salvia miltiorrhiza is a traditional medicinal plant used in Asian medicine for various therapeutic purposes. This plant contains numerous bioactive secondary metabolites, particularly abietane-type diterpenoids. In this study, 16 abietane-type diterpenoids were isolated from S. miltiorrhiza root extracts and structurally identified through advanced spectroscopic techniques. Among them, tanshinone IIA (6) and 15,16-dihydrotanshinone I (11) exhibited potent α-glucosidase inhibition, with IC 50 values of 48.38 ± 0.57 and 48.02 ± 0.47 µM, respectively. Enzyme kinetic studies revealed that these compounds served as non-competitive inhibitors of α-glucosidase. Our findings indicate that natural compounds from S. miltiorrhiza show promise as safe and effective α-glucosidase inhibitors, providing an alternative approach to diabetes treatment. This study contributes to the growing interest in utilizing natural sources for α-glucosidase inhibition and their potential application in healthcare and disease management.

Inhibitory Activity of PTP1B and α-Glucosidase by Compounds from Whole Plants of Houttuynia cordata Thunb

In this study, twenty known compounds were isolated from Houttuynia cordata Thunb., including four megastigmanes (1‒4), four phenolics (5, 6, 9, and 10), one tetrahydro-2-one derivative (12), four coumarins (7, 13, 14, and 16), six caffeic acid derivatives (8, 11, 15, 17, 18, and 19), and one triterpenoid (20). Their chemical structures were established using NMR spectra and comparison with literature. The anti-diabetic activity of the isolated compounds was assessed by investigating their inhibitory effects on protein tyrosine phosphatase 1B (PTP1B) and α-glucosidase. The results revealed that ginnalin A (10) and 3-(4′-hydroxyphenyl)-2-propenoic acid (4′′-carboxyl)-phenyl ester (13) exhibited significant inhibitory effects on both PTP1B and α-glucosidase with IC 50 values of 7.9 ‒ 37.6 and 13.9 ‒ 31.9 μM, respectively. In the kinetic study, these two compounds showed noncompetitive-type PTP1B and α-glucosidase inhibition, with K i values of 35.6 and 7.3 μM for PTP1B and 13.9 and 31.0 μM for α-glucosidase, respectively. These findings highlight the potential of the isolated compounds as candidates for the development of novel therapeutic agents for diabetes.

Phytochemical Investigation of Active Compounds from Celastrus orbiculatus Thunb. with α-Glucosidase Inhibitory Activity

Diabetes, characterized by elevated blood glucose levels, has a significant impact on cardiovascular, neural, and vascular systems. α-Glucosidase inhibitors have emerged as potential therapeutic agents for type 2 diabetes, as they slow carbohydrate digestion and reduce postprandial blood sugar levels. In this study, we investigated the phytochemical and pharmacological properties of Celastrus orbiculatusThunb., renowned for its diverse phytochemical constituents and potential medicinal applications. Through the application of chromatographic and spectroscopic techniques, we successfully isolated and structurally elucidated 16 compounds from the stems of C. orbiculatus. The in vitro α-glucosidase inhibitory activity of these compounds was evaluated. Notably, celaphanol A (1) and (+) lariciresinol (7) exhibited strong α-glucosidase inhibition, with IC 50 values of 8.06 ± 0.30 and 48.02 ± 0.47 µM, respectively. Enzyme kinetics analysis revealed that the most active compound 1 acted as a non-competitive inhibitor against α-glucosidase, with a K i> value of 7.77 ± 0.16 µM. These findings underscore C. orbiculatus as a valuable source for discovering and developing new α-glucosidase inhibitors. Furthermore, compound 1 shows promise as a candidate for natural herbal therapy targeting α-glucosidase inhibition. This suggests the potential for further investigation into its effectiveness through in silico or in vivo studies using a diabetes model.

Anti-inflammatory and Cytotoxic Activities of Phenolic Compoundsfrom Broussonetia kazinoki

The phytochemical investigation of Broussonetia kazinoki roots led to the isolation of ten compounds, including six flavonoids (1–6), two lignans (7 and 8), and two coumarins (9 and 10) by comparing their 1H and 13C NMR spectra with reference values. To the best of our knowledge, compounds 9 and 10 were isolated from this plant for the first time. Among the ten isolates, compounds 2, 4, and 6 exhibited inhibitory effects against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in macrophage RAW264.7 cells with IC50 values of 11.98, 10.16, and 24.06 μM, respectively. Furthermore, compounds 2, 4, and 6 reduced LPS-induced inducible nitric oxide synthase (iNOS) expression in a dose-dependent manner. Pre-incubation of cells with these compounds also significantly suppressed LPS-induced COX-2 protein expression. Compounds 2, 4, and 6 also showed cytotoxic activity against HL-60 cells with IC50 values ranging between 46.43 and 94.06 μM.

Anti-inflammatory and Cytotoxic Activities of Phenolic Compoundsfrom Broussonetia kazinoki

The phytochemical investigation of Broussonetia kazinoki roots led to the isolation of ten compounds, including six flavonoids (1–6), two lignans (7 and 8), and two coumarins (9 and 10) by comparing their 1H and 13C NMR spectra with reference values. To the best of our knowledge, compounds 9 and 10 were isolated from this plant for the first time. Among the ten isolates, compounds 2, 4, and 6 exhibited inhibitory effects against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in macrophage RAW264.7 cells with IC50 values of 11.98, 10.16, and 24.06 μM, respectively. Furthermore, compounds 2, 4, and 6 reduced LPS-induced inducible nitric oxide synthase (iNOS) expression in a dose-dependent manner. Pre-incubation of cells with these compounds also significantly suppressed LPS-induced COX-2 protein expression. Compounds 2, 4, and 6 also showed cytotoxic activity against HL-60 cells with IC50 values ranging between 46.43 and 94.06 μM.

Development and Validation of an HPLC-PDA Method for Quantitation of Ten Marker Compounds from Eclipta prostrata (L.) and Evaluation of Their Protein Tyrosine Phosphatase 1B, α-Glucosidase, and Acetylcholinesterase Inhibitory Activities

The aerial parts of Eclipta prostrata is used as a traditional medicine and vegetable. In traditional folk medicine, it is used for treatment of hemorrhages, hepatic, disease, renal injuries, hair loss, tooth mobility, and viper bites. In this study, ten compounds (1 ‒ 10) were isolated from the aerial parts of E. prostrata. A reliable high performance liquid chromatography equipped with photometric diode array detector (HPLC-PDA) method was developed to simultaneously quantitate 10 marker compounds [chlorogenic acid (1), paratensein 7-O-β-ᴅ-glucoside (2), quercetin 7-O-β-ᴅ-glucoside (3), luteolin 7-O-β-ᴅ-glucoside (4), apigenin 7-O-β-ᴅ-glucoside (5), apigenin 4'-O-β-ᴅ-glucoside (6), apigenin (7), luteolin (8), wedelolactone (9), and paratensein (10)]. In addition, compounds 5 and 6 showed considerable inhibitory effects against protein-tyrosine phosphatase 1B (PTP1B) enzyme. Moreover, compounds 6 ‒ 8, and 10 exhibited potent α-glucosidase inhibitory effects with IC50 values of 24.5 ± 1.9, 33.0 ± 0.5, 45.5 ± 0.1, and 23.8 ± 1.0 µM, respectively. All compounds (1 ‒ 10) showed considerable acetylcholinesterase (AChE) inhibitory effects with IC 50 ranging from 30.1 to 75.2 µM.

Development and Validation of an HPLC-PDA Method for Quantitation of Ten Marker Compounds from Eclipta prostrata (L.) and Evaluation of Their Protein Tyrosine Phosphatase 1B, α-Glucosidase, and Acetylcholinesterase Inhibitory Activities

The aerial parts of Eclipta prostrata is used as a traditional medicine and vegetable. In traditional folk medicine, it is used for treatment of hemorrhages, hepatic, disease, renal injuries, hair loss, tooth mobility, and viper bites. In this study, ten compounds (1 ‒ 10) were isolated from the aerial parts of E. prostrata. A reliable high performance liquid chromatography equipped with photometric diode array detector (HPLC-PDA) method was developed to simultaneously quantitate 10 marker compounds [chlorogenic acid (1), paratensein 7-O-β-ᴅ-glucoside (2), quercetin 7-O-β-ᴅ-glucoside (3), luteolin 7-O-β-ᴅ-glucoside (4), apigenin 7-O-β-ᴅ-glucoside (5), apigenin 4'-O-β-ᴅ-glucoside (6), apigenin (7), luteolin (8), wedelolactone (9), and paratensein (10)]. In addition, compounds 5 and 6 showed considerable inhibitory effects against protein-tyrosine phosphatase 1B (PTP1B) enzyme. Moreover, compounds 6 ‒ 8, and 10 exhibited potent α-glucosidase inhibitory effects with IC50 values of 24.5 ± 1.9, 33.0 ± 0.5, 45.5 ± 0.1, and 23.8 ± 1.0 µM, respectively. All compounds (1 ‒ 10) showed considerable acetylcholinesterase (AChE) inhibitory effects with IC 50 ranging from 30.1 to 75.2 µM.

Terpenoids from Citrus unshiu Peels and Their Effects on NO Production

Two new compounds, 3-methyl-but-2-en-1-yl-1-O-β-xylopyranosyl-(1ʺ→2ʹ)-O-β-glucopyranoside (1) and 1-O-β-glucopyranosyl-6-hydroxy-2-methyl-hep-2-enoic acid (2), along with sixteen known terpenoids were isolated from the peels ofCitrus unshiu Markov. Their structures were elucidated based on extensive NMR analyses ( 1 H NMR, 13 C NMR, DEPT, COSY, HMQC, and HMBC) and high-resolution mass spectrometry. In addition, all isolates (1 - 18) were tested their effects on nitric oxide (NO) production in RAW264.7 cells. Limonin (15) showed to inhibit LPS-induced NO production in a concentration-dependent manner without cytotoxicity.

Chemical Constituents from the Aerial Parts of Artemisia capillaris Thunb. and Their Anti-allergic and Anti-inflammatory Effects

Artemisia capillaris Thunb. (Compositae) is a traditional medicinal plant with various pharmacological activities. To elucidate new anti-allergic and anti-inflammatory constituents, the aerial parts of A. capillaries were investigated to afford a new compound, (6E,8E)-6-methylundeca-6,8-diene-2,5,10-trione (17) together with 19 known compounds (1 - 16, 18 - 20). The structures of these compounds were determined by extensive spectroscopic analyses including 1D, 2D NMR, HREIMS, and optical rotation [α]D. The absolute configuration of compound 2 was determined to be S form for the first time. All isolates (1 - 20) were tested their inhibitory effects on interleukin 2 (IL-2) expression in T cells and NO production in lipopolysaccharide (LPS)-stimulated RAW246.7. Among them, compounds 10, 11, 19, and 20 reduced IL-2 expression in a dose-dependent manner. In addition, compound 10 also inhibited NO production with an IC50 value of 37.3 ± 0.4 μM.

Biological Activity of Chemical Constituents Isolated from Strain Chlamydomonas sp. KSF108 (Chlamydomonadaceae)

This study focused on investigation of the immunosuppressive inhibitory effect through determination of IL-2 production of nine compounds (1 − 9) isolated from Chlamydomonas sp. KSF108. Among them, compounds 1, 5, and 6 displayed moderately inhibitory effects on IL-2 production at a concentration of 100 μM. In addition, the related ones including cytotoxic, anti-inflammatory, and anti-oxidant activities were also elucidated. 6 further displayed cytotoxic activity against the MCF-7 cell line, with an IC50 value of 17.2 μM and 4, 6 − 7, and 9 possessed significant DPPH radical scavenging activity, with IC50 values ranging from 3.1 to 4.4 μM. To the best of our knowledge, this is the first report on the bioactivity of isolated chemical constituents from the genus Chlamydomonas. Compounds 1 and 5 investigated for the first time in the activity of immunosuppressivity and 6 may come to serve as the most important marker in broad-spectrum activities of the secondary metabolites identified from C. sp. KSF108.

Cytotoxic Lactones from the Pericarps of Litsea japonica

From the pericarps of Litsea japonica (Thunb.) Jussieu, eighteen butanolide derivatives (1 – 18) were evaluated for their cytotoxic activity against HeLa, HL-60, and MCF-7 cells. Compounds 1 – 9 with 2-alkylidene-3-hydroxy-4-methylbutanolides structure exhibited cytotoxic activities against cancer-cell lines. Among them, compound 8 (litsenolide D₂) exhibited the most potent cytotoxicity against the tested cell lines, including HeLa, HL-60, and MCF-7, with IC₅₀ values of 17.6 ± 1.3, 4.2 ± 0.2, and 12.8 ± 0.0 µM, respectively. Compound 8 induced apoptosis in a dose-dependent manner. Annexin V/Propidium Iodide (PI) double staining confirmed that 8 effectively induced apoptosis in MCF-7 cells. To the best of our knowledge, we have reported cytotoxic activity of butanolides from L. japonica against these cancer-cell lines for the first time.

Quantitation and Radical Scavenging Activity Evaluation of Iridoids and Phenylethanoids from the Roots of Phlomis umbrosa (Turcz.) using DPPH Free Radical and DPPH-HPLC Methods, and their Cytotoxicity

The roots of Phlomis umbrosa (Turcz.) (Phlomidis Radix) have been traditionally used to treat cold, reduce swelling and staunch bleeding. Four iridoids (1 – 3 and 5) and six phenylethanoid derivatives (4, and 6 – 10) were isolated from the roots of P. umbrosa. A simple, sensitive, and reliable analytical HPLC/PDA method was developed, validated, and applied to determine 10 marker compounds in Phlomidis Radix. Furthermore, the isolates were evaluated for cytotoxic and anti-oxidant activities as well as DPPH-HPLC method. Among them, compounds 4 and 6 – 9 displayed potent anti-oxidant capacities using DPPH assay with IC50 values of 27.7 ± 2.4, 10.2 ± 1.1, 18.0 ± 0.8, 19.1 ± 0.3, and 19.9 ± 0.6 µM, and compounds 6, 8, and 9 displayed significant cytotoxic activity against HL-60 with IC50 values of 35.4 ± 3.1, 18.6 ± 2.0, and 42.9 ± 3.0 µM, respectively.

Development of Analytical Method and Validation using HPLC/PDA for Discrimination between Artemisiae Argyi Folium and Artemisiae Iwayomogii Herba

In this study, we described the new developed method to simultaneously discriminate two herbal drugs of Artemisiae Argyi Folium and Artemisiae Iwayomogii Herba using eight marker compounds (1 – 8) on an HPLC-PDA system. The developed method was applied to quantify the major components of two herbal drugs. The pattern analysis successfully discriminated and evaluated different components between Artemisiae Argyi Folium and Artemisiae Iwayomogii Herba. Results were used for classification of different species from collected samples.

Development and Validation of HPLC-PDA Method and Pattern Recognition Analyses Using Eight Marker Compounds for the Quality Control Between the Seeds of Cuscuta chinensis Lam. and Cuscuta japonica Choisy

Cuscuta chinensis Lam. and Cuscuta japonica Choisy are parasitic plants. C. chinensis seeds were traditionally used for treatment of kidney and liver deficiencies. C. japonica seeds were used as tonic medicine to improve liver function and strengthen kidneys, treatment of high blood pressure, chronic diarrhea, and sore eyes. Cuscutae Semen are seeds of only C. chinensis in Korean Herbal Pharmacopoeia (K.H.P.). The developed HPLC-PDA method easily, accurately, and sensitively quantified using eight marker compounds [hyperoside (1), astragalin, (2), quercetin (3), kaempferol (4), chlorogenic acid (5), 3,4-di-O-caffeoylquinic acid (6), 1,5-di-O-caffeoylquinic acid (7), and 4,5-di-O-caffeoylquinic acid (8)]. In addition, the method may be used to distinguish seeds between C. chinensis Lam. and C. japonica Choisy. Furthermore, the result from the current study was applied to clarify samples between steam processed and unprocessed samples of C. chinensis by pattern analysis.

Anti-inflammatory and Immunosuppressive Effects of Panax notoginseng

Here, we designed to examine the anti-inflammatory effects on RAW264.7 cells and the immunosuppressive effects by evaluating interleukin-2 (IL-2) production in Jurkat T cells using a MeOH extract of Panax notoginseng roots. The results showed that the MeOH extract inhibited the synthesis of nitric oxide (NO) in a dose-dependent manner (IC₅₀ value of 7.08 µg/mL) and displayed effects on T cell activation at a concentration of 400 µg/mL. In efforts to identify the potent compounds, bioactivity-guided fractionation of the MeOH extract and chemical investigation of its active CH₂Cl₂-, EtOAc-, and butanol-soluble fractions led to the successful isolation and identification of eleven compounds, including two polyacetylenes (1, 2), a steroid saponin (3), seven dammarane-type ginsenosides (4 – 10), and an oleanane-type ginsenoside (11). Among them, compound 11 was isolated from this plant for the first time. Compound 2 exhibited potent inhibitory effects on NO synthesis and an immunosuppressive effect with IC₅₀ values of 2.28 and 65.57 µM, respectively.

Antioxidant Compounds Isolated from the Roots of Phlomis umbrosa Turcz

Two triterpenoids, arjunolic acid (1), belleric acid (2), five phenylethanoids, martynoside (3), orobanchoside (4), 3,4-dihydroxyphenethylalcohol-6-O-caffeoyl-β-D-glucoside (5), leucosceptoside B (6), lunariifolioside (7), four phenolic acids, ferulic acid (8), syringic acid (9), vanillic acid (10), 4-hydroxybenzoic acid (11), and one lignan, (+)-syringaresinol-β-D-glucoside (12), were isolated from the roots of P. umbrosa. All isolated compounds were explored for their antioxidant potential in the DPPH and ABTS assays. In DPPH assay, compound 5 showed high antioxidant capacity. Compounds 3, 4, 6, and 7 displayed considerable antioxidant activities. In addition, compounds 5–7 exhibited potential antioxidant capacities in the ABTS assay.

Cytotoxic Triterpenoids from the Fruits of Ligustrum japonicum

Medicinal plants are potential sources of anticancer agents screening. A large number of phytochemicals, including triterpenoids, have been reported to have significant cytotoxic effects on cancer cells. From the fruits of Ligustrum japonicum Thunb., thirteen triterpenoids (1 – 13) were isolated and evaluated for their cytotoxic activity against Hela and HL-60 cells. As results, 8 (oleanolic acid) showed significant effects on Hela with IC50 values of 5.5 µM, and moderate effects on HL-60 cells with IC₅₀ values of 55.9 µM. Meanwhile, 10 (oleanderic acid) and 11 (3β-acetoxy-urs-12-en-28-oic acid) exhibited moderate inhibitory effects on Hela with IC₅₀ value of 55.0 and 68.8 µM, respectively. Moreover, 10 showed cytotoxic effect on HL-60 cell line with IC₅₀ value of 63.9 µM. To our knowledge, this is the first report that oleanderic acid was isolated from L. japonicum and investigated in cytotoxic effects on Hela and HL-60 cells.

Sesquiterpenoids from the heartwood of Juniperu s chinensis

A new sesquiterpenoid, 11-hydroxy-valenc-1(10),3(4)-dien-2-one (3), two chemically synthesized but first isolate from nature, 3-oxocedran-8β-ol (1) and valenc-1(10),3(4),11(12)-trien-2-one (2) along with four known compounds, sugiol (4), (+)-nootkatone (5), 11-hydroxy-valenc-1(10)-en-2-one (6), and clovandiol (7), were isolated from the heartwood of Juniperus chinensis. All chemical structures were elucidated using extensive spectroscopic analysis including 1D and 2D NMR spectroscopy. Valenc-1(10),3(4),11(12)-trien-2-one (2) exhibited significant inhibitory activity against butyrylcholinesterase with an IC₅₀ value of 68.45 µM.