The chemical profiles and cytotoxicity of gaharu bouya oil from Borneo's Gonystylus bancanus wood.

Gaharu bouya oil obtained from distillation of the woods from Gonystylus genus has attracted essential oil industry interest. However, the information about gaharu bouya essential oil profile is limited. The presence of Gonystylus species is also critically endangered on the IUCN Red List. Therefore, exploring the -omics profiles of Gonystylus bancanus, a native plant from Borneo Island, is important for Indonesia to conserve the population. This research investigated the metabolite profiling of G. bancanus oil, especially the volatile components of its essential oils. Distillations were performed in two technical ways: hydrodistillation on a laboratory scale and steam distillation on an industrial scale. According to LC-MS and GC-MS profiles, both essential oils displayed similar chemical compositions. This article also discusses the similarity of the chemical contents of gaharu bouya oil and agarwood oil from the gaharu superior type (Aquilaria) to support the value of the oil. This research also investigated the cytotoxicity of gaharu bouya oil against three cell lines: HeLa, MCF-7, and HT-29.

Antiplasmodial and anticancer activities of xanthones isolated from Garcinia bancana Miq.

This report describes the isolation and characterization of xanthones from Garcinia bancana Miq. and evaluates their antiplasmodial and anticancer activities. Macluraxanthone (1), isojacareubin (2), and gerontoxanthone C (3) were isolated from the stem bark of G. bancana Miq. for the first time. In silico molecular docking studies revealed the hydrogen bonding and steric interactions between xanthones (1-3) and PfLDH/VEGFR2. The in vitro antiplasmodial activity was assayed against the chloroquine-sensitive Plasmodium falciparum strain 3D7 by the lactate dehydrogenase (LDH) method. The anticancer evaluation was evaluated against the A549, MCF-7, HeLa, and B-16 cancer cell lines. Compounds (1) (IC50 8.45-16.71 µM) and (3) (IC50 9.69-14.86 µM) showed more potent anticancer activity than compound (2) (IC50 25.46-31.31 µM), as well for their antiplasmodial activity (4.28 µM, 5.52 µM, 11.45 µM). Our findings indicated the potential of G. bancana Miq. as a natural resource of antiplasmodial and anticancer compounds.

Antioxidant and α-glucosidase inhibitory activities of compound isolated from Stachytarpheta jamaicensis (L) Vahl. leaves.

Stachytarpheta jamaicensis is one of the folk medicines used for the treatment of diabetes in Ambon, Indonesia, but there are limited studies on the bioactivities of its constituents. This study aims to assess the antioxidant and antidiabetic activities of four extracts of S. jamaicensis leaves extracted using several solvents. Bioassay guided fractionation on each extract establishes for exploring S. jamaicensis leaves active compounds. The antioxidant was evaluated using the DPPH and ABTS methods, while the α-glucosidase inhibitory was carried out in vitro assay. The results showed that the methanol extract of S. jamaicensis leaves displays inhibition of DPPH, ABTS and α-glucosidase activity compared to other solvent extracts. Furthermore, 6ß-hydroxyipolamiide was successfully isolated from the methanol extract of S. jamicensis leaves which was reported to have α-glucosidase inhibitory activity with an IC50 of 539.17 µg/mL. Based on the results, S. jamaicensis could be recommended as an antioxidant and antidiabetic agent.

Metabolite profiling of Borneo's Gonystylus bancanus through comprehensive extraction from various polarity of solvents.

Gonystylus bancanus wood or ramin wood has been generally known as a source of agarwood (gaharu) bouya, a kind of agarwood inferior type, or under the exported trading name of aetoxylon oil. The massive exploitation of ramin wood is causing this plant's extinction and putting it on Appendix II CITES and IUCN Red List of Threatened Species. To date, no scientific publication concerns the chemical exploration of G. bancanus wood and preserving this germplasm through its metabolite profiling. Therefore, research focused on chemical components profiling of G. bancanus is promised. This research is aimed to explore metabolomics and analyze the influence of solvent polarities on the partitioning of metabolites in G. bancanus wood. A range of solvents in different polarities was applied to provide comprehensive extraction of metabolites in G. bancanus wood. Moreover, a hydrodistillation was also carried out to extract the volatile compounds despite the non-volatile ones. LCMS and GCMS analyses were performed to identify volatile and non-volatile components in the extracts and essential oil. Multivariate data analysis was processed using Principal Component Analysis (PCA) and agglomerative hierarchical clustering. 142 metabolites were identified by LCMS analysis, while 89 metabolites were identified by GCMS analysis. Terpenoids, flavonoids, phenyl propanoids, and saccharides are some major compound classes available from LCMS data. Oxygenated sesquiterpenes, especially 10-epi-γ-eudesmol, and ß-eudesmol, are the major volatile components identified from GCMS analysis. PCA of LCMS analysis demonstrated that PC1 discriminated two clusters: essential oil, dichloromethane, and n-hexane extracts were in the positive quadrant, while methanol and ethyl acetate extracts were in the negative quadrant. Three-dimensional analysis of GCMS data revealed that n-hexane extract was in the superior quadrant, and its composition can be significantly distinguished from other extracts and essential oil. G. bancanus wood comprises valuable metabolites, i.e., terpenoids, which benefit the essential oil industry. Comprehensive extraction by performing solvents in different polarities on G. bancanus wood could allow exploration of fully extracted metabolites, supported by the exhibition of identified metabolites from LCMS and GCMS analysis.

Optimization of total phenolic content, total flavonoid content and anti-gout properties of polyherbal formulation.

OBJECTIVES: An increase in gout prevalence has drawn attention among society and this situation drives the exploration of more favourable treatment using traditional medicinal plants which are rich in phenolic and flavonoid to avoid the side effects of modern medication. However, there are only few studies regarding the optimization of phytochemicals and anti-gout properties of medicinal plants and their combinations. The objectives of this study were to determine the optimal formulation of Strobilanthes crispus, Orthosiphon stamineus Benth and Stevia rebaudiana with maximum total phenolic and flavonoid contents as well as minimum IC50 of in vitro xanthine oxidase inhibitory activity and to examine their correlations among the formulations. METHODS: Plant extracts from hot water infusion were tested for the total phenolic content, total flavonoid content and enzyme inhibition through Folin-ciocalteu assay, aluminium chloride method and xanthine oxidase inhibition assay, respectively. Simplex-centroid mixture design was applied in this study and 13 polyherbal formulations were generated by Design Expert Software. RESULTS: Linear, special cubic and quadratic models were selected to describe the interaction effect between polyherbal formulations and their responses. Low IC50 value (13.90 µg/mL) of xanthine oxidase activity was found in the binary combination of O. stamineus and S. rebaudiana and this probably related to its high phenolic and flavonoid contents as xanthine oxidase inhibition and phytochemicals were correlated. CONCLUSIONS: The suggested optimal formulation was comprised of 44.26 % O. stamineus and 55.74 % S. rebaudiana and it could be developed as an alternative treatment for gout.

A new biphenyl from the stem bark of Garcinia macrantha A.C.Sm.

In our continuation of exploring antidiabetic agents from Garcinia species, we found that the methanolic extract of G. macrantha A.C.Sm. exhibited considerable α-glucosidase inhibition of 58.20 ± 0.37% in sucrose substrate and 39.86 ± 2.07% in maltose substrate at 100 µg/mL. Phytochemical investigation on the extract revealed the presence of a new biphenyl, macrabiphenyl A, which was successfully elucidated by means of spectroscopic methods (HRESIMS and 1D and 2D NMR). The α-glucosidase inhibitory evaluation indicated that the new compound was weakly active against the enzyme.

Antidiabetic, cytotoxic and antioxidant activities of Rhodomyrtus tomentosa leaf extracts.

As part of our project on exploring Indonesian medicinal plants for antidiabetic and anticancer agents, this study was conducted to investigate the total phenolic and flavonoid contents, and antioxidant, cytotoxic and antidiabetic properties of R. tomentosa leaf extracts. The antioxidant activity was tested using DPPH, ABTS, and FRAP methods. In vitro cytotoxic assay was performed against MCF-7, HeLa, A549, and B16 cancer cell lines. The in vitro antidiabetic testing was determined using α-glucosidase and α-amylase inhibitory evaluation, while STZ-induced diabetic rats were used for in vivo study. The highest values of total phenolic (191.97 ± 0.19 mg GAE g-1) and flavonoid (29.11 ± 0.05 mg QE g-1) contents were recorded in methanolic extract. This extract also showed the highest DPPH and ABTS activities with IC50 values of 7.79 ± 0.03 and 4.03 ± 0.02 µg mL-1, respectively, as well as the highest FRAP activity with a value of 64.05 ± 0.54 µM Fe2+ g-1. The methanol extract had cytotoxicity against MCF-7, HeLa, A549, and B16 cancer cell lines with IC50 values of 123.49 ± 0.79, 28.28 ± 0.17, 168.88 ± 1.14, and 42.44 ± 0.18 µg mL-1, respectively. In vitro antidiabetic evaluation indicated that the MeOH extract inhibited α-glucosidase and α-amylase with IC50 values of 45.73 ± 1.06 and 41.31 ± 1.12 µg mL-1, respectively. A dose of 400 mg kg-1 body weight of the MeOH extract reduced rats' blood glucose rate and serum blood glucose by 48.51% and 17.73%, respectively after 15 days of treatment. Taken together, these findings suggested that the methanolic extract of R. tomentosa leaves can be used as a potential source of antioxidant, cytotoxic, and antidiabetic agents.

Biological Activity Evaluation and In Silico Studies of Polyprenylated Benzophenones from Garcinia celebica.

This study aimed to isolate polyprenylated benzophenones from the rootbark of Garcinia celebica and assess their activities in vitro and in silico. The antioxidant activity was evaluated by the DPPH, ABTS, and FRAP methods. The cytotoxicity was evaluated against HeLa, MCF-7, A549, and B16 cancer cell lines. The antiplasmodial activity was performed against the chloroquine-sensitive Plasmodium falciparum strain 3D7. Molecular docking was analyzed on alpha-estrogen receptor (3ERT) and P. falciparum lactate dehydrogenase enzyme (1CET). The prediction of ADMET for the compounds was also studied. For the first time, (-)-cycloxanthochymol, isoxanthochymol, and xanthochymol were isolated from the root bark of Garcinia celebica. The antioxidant and cytotoxicity evaluation showed that all benzophenones exhibited antioxidant activity compared to gallic acid and quercetin as positive controls and also exhibited strong activity against HeLa, MCF-7, A549, and B16 cell lines compared to cisplatin as the positive control. The antiplasmodial evaluation showed that isoxanthochymol exhibited activity against the chloroquine-sensitive P. falciparum strain 3D7. In addition, the in silico molecular docking study supported in vitro activities. The ADMET analysis also indicated the isolated benzophenones are potential oral drug candidates.

Chemistry of trisindolines: natural occurrence, synthesis and bioactivity.

Heterocyclic nitrogen compounds are privileged structures with many applications in the pharmaceutical and nutraceutical industries since they possess wide bioactivities. Trisindolines are heterocyclic nitrogen compounds consisting of an isatin core bearing two indole moieties. Trisindolines have been synthesized by reacting isatins with indoles using various routes and the yield greatly depends on the catalyst used, reaction conditions, and the substituents on both the isatin and indole moieties. Amongst the synthetic routes, acid-catalyzed condensation reaction between isatins and indoles are the most useful due to high yield, wide scope and short reaction times. Trisindolines are biologically active compounds and show anticancer, antimicrobial, antitubercular, antifungal, anticonvulsant, spermicidal, and antioxidant activities, among others. Trisindolines have not previously been reviewed. Therefore, this review aims to provide a comprehensive account of trisindolines including their natural occurrence, routes of synthesis, and biological activities. It aims to inspire the discovery of lead trisindoline drug candidates for further development.

Chemical constituents, usage and pharmacological activity of Cassia alata.

Cassia alata or locally known as Ketepeng Cina (Indonesia) and Gelenggang (Malaysia) has been used as a traditional medicine to treat various diseases, especially skin diseases. In addition, C. alata has been reported to have potential anti allergic, anti inflammatory, antioxidant, anticancer, antidiabetic, and antifungal. Metabolite compounds that have been isolated from C. alata include flavones, flavonols, flavonoids glycosides, alatinon, alanonal and ß-sitosterol-ß-D-glucoside. The compounds have been isolated mainly from the leaves. Further identification is needed to discover the secondary metabolites from other parts of the plant such as seed, flower and bark which are reported to have potent antibacterial and antifungal activity. Therefore, this article highlights the secondary metabolites and biological activity of this plant which has been shown to have pharmacological properties against selected diseases.

α-VINIFERIN as a potential antidiabetic and antiplasmodial extracted from Dipterocarpus littoralis.

Over the past few decades, complementary medicine therapy using medicinal plants have been developed in healthcare. Phytochemical studies about medicinal plants have been conducted to verify their potency as medicinal remedies in modern therapeutics. Dipterocarpus littoralis commonly known as Meranti Jawa in Indonesia is traditionally used to treat diseases such as diarrhea, diabetic and malaria. This study aimed to isolate bioactive compounds from D. littoralis using bioguided fractionation method. The bioactivity measured were antioxidant, antidiabetic, and antiplasmodial activity. Alpha-glucosidase and alpha-amylase assays were applied to estimate the in vitro antidiabetic activity of D. littoralis. The antioxidant activities were determined by using the free radical scavenging assays 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2-2″-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). Analysis of total flavonoid and phenolic contents were expressed as Quercetin Equivalent (QE) and Gallic Acid Equivalent (GAE), respectively. The in vitro antiplasmodial activity test of methanol extract of D. littoralis was also conducted against Plasmodium falciparum strain 3D7. Purification of the ethyl acetate fraction of the methanol extract of D. littoralis resulted in an oligostilbenes namely α-viniferin (1). The structure of the α-viniferin was characterized by comprehensive spectral analysis including IR, 1D and 2D NMR, and in comparison with the literature data. Compound 1 showed an alpha-glucosidase and alpha-amylase inhibitory activity with IC50 values of 256.17 and 212.79 µg/mL, respectively. The in vitro antiplasmodial activity test against Plasmodium falciparum strain 3D7 at a concentration of 100 µg/mL revealed a strong antiplasmodial inhibitory activity with IC50 value of 2.76 µg/mL. Our findings indicated that α-viniferin (1) which is isolated from D. littoralis extract could be regarded as potential antidiabetic and antiplasmodial resources in the future.

BCR-ABL Gene Transcript Types of Patients with Chronic Myelogenous Leukemia in Yogyakarta, Indonesia.

The aim of this study was analyzing the BCR-ABL transcript types of patients with chronic myeloid leukemia (CML) in Dr Sardjito General Hospital, Yogyakarta, Indonesia. This study is very relevant because the data concerning BCR-ABL gene transcript types is very limited in Indonesia. Furthermore, it is important for patient's management, particularly in defining the tyrosine kinase inhibitors (TKIs) therapy and monitoring after therapy. The introduction of TKIs has become a major advance in the management of patients with CML, especially in the chronic phase (CML-CP), in which most patients are diagnosed. METHODS: One hundred eighty five (185) of 370 recruited patients were included in this study (2010-2014). RNA samples were isolated from mononuclear cells of peripheral blood of the subjects taken at primary diagnosis. Detection of BCR-ABL gene transcript types was done using multiplex reverse transcriptase PCR (multiplex RT-PCR) and/or nested PCR following the cDNA synthesis. When the first PCR set failed to amplify the BCR-ABL gene, RT-conventional PCR and/or nested PCR would be applied. The proportion of each transcript type was calculated among the BCR-ABL positive CML patients. RESULTS: Approximately 99% (183/185) of CML patients are BCR-ABL positive, with the most common type is major b3a2 (136/183; 74.3%), followed by major b2a2 (41/183; 22.4%). Two samples (1.1%) showed co-expression of b3a2 and b2a2; 1 sample showed co-expression of b3a2 and fragment at 500bp; and 3 samples showed uncommon fragments. CONCLUSION: Ninety nine percent (99%) of CML patients in Yogyakarta, Indonesia are BCR-ABL positive, with 74.3% have b3a2 transcript, 22.4% have b2a2 trascript, 1.1% have co-expression of b3a2 and b2a2 transcript, and the rest (2.2%) have uncommon bands that still need to be confirmed.

Optimization of Extraction Conditions of Phytochemical Compounds and Anti-Gout Activity of Euphorbia hirta L. (Ara Tanah) Using Response Surface Methodology and Liquid Chromatography-Mass Spectrometry (LC-MS) Analysis.

Gout is a common disease affected most of the people due to the elevation of uric acid in the blood. Flavonoid and phenolic compounds are reported to exert the anti-gout activity of medicinal plants. Hence, this study aimed at optimizing the extraction conditions of phenolic and flavonoid compounds as well as the anti-gout (xanthine oxidase inhibitory activity) in vitro of Euphorbia hirta using response surface methodology (RSM). The plant part used was the whole plant excluding roots. The effects of three independent variables (extraction time, X 1; extraction temperature, X 2; and solid-to-liquid ratio, X 3) on three response variables (total flavonoid content, Y 1; total phenolic content, Y 2; and xanthine oxidase inhibitory activity, Y 3) were determined using central composite design (CCD) while phytochemical profiling of the extracts was determined by liquid chromatography-mass spectrometry (LC-MS). Quadratic models produced a satisfactory fitting of the experimental data with regard to total flavonoid content (r 2 = 0.9407, p < 0.0001), total phenolic content (r 2 = 0.9383, p < 0.0001), and xanthine oxidase inhibitory activity (r 2 = 0.9794, p < 0.0001). The best extraction conditions observed for total flavonoid content, total phenolic content, and xanthine oxidase inhibitory activity were at a temperature of 79.07°C for 17.42 min with solid-to-liquid ratio of 1 : 20 g/ml. The optimum values for total flavonoid, total phenolic, and xanthine oxidase inhibitory activity were 67.56 mg RE/g, 155.21 mg GAE/g, and 91.42%, respectively. The main phytochemical compounds in the optimized E. hirta extract are neochlorogenic acid, quercetin-3ß-D-glucoside, syringic acid, caffeic acid, ellagic acid, astragalin, afzelin, and quercetin. As conclusion, this study clearly demonstrated the best conditions to obtain higher xanthine oxidase inhibitory activity and phytochemical compounds which can be further used for the development of anti-gout agents.

A New Flavanone as a Potent Antioxidant Isolated from Chromolaena odorata L. Leaves.

Chromolaena odorata L. (Asteraceae) is one of the tropical plants which is widely used as traditional medicines for diabetes and soft tissue wounds treatment in some regions in East Indonesia. The present study was aimed at determining the bioactive compounds of C. odorata leaves. The methanol and ethyl acetate extracts of C. odorata leaves have the inhibitory activity against 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals as well as α-glucosidase rat intestine enzyme. A new flavanone was isolated from the methanol extract and elucidated as 5,3'-dihydroxy-7,6'-dimethoxyflavanone or, namely, odoratenin (1) together with two known compounds: isosakuranetin (2) and subscandenin (3). The antioxidant activity of odoratenin (1) exhibited very potent ABTS radical inhibitory activity with IC50 value of 23.74 µM which is lower than that of trolox (IC50 31.32 µM) as a positive control. The result showed that a new flavanone, odoratenin (1), should be potential as an antioxidant source.

Xanthones and biphenyls from the stems of Garcinia cylindrocarpa and their cytotoxicity.

Six new compounds including four new xanthones, cylindroxanthones D-G (1-4), and two new biphenyls, cylindrobiphenyls A and B (5 and 6), were isolated from the stems of Garcinia cylindrocarpa together with 28 known compounds (7-34). The structures of the new compounds were established on the basis of extensive 1D and 2D NMR and HRESIMS spectroscopic analysis. Their cytotoxicity was evaluated against five human cancer cell lines including KB, HeLa S-3, MCF-7, Hep G2, and HT-29. Compound 23 showed strong cytotoxicity against KB, HeLa S-3, MCF-7, and Hep G2 cells with IC50 values in the range of 2.20-6.00 µM. Furthermore, compound 25 selectively exhibited good cytotoxicity against MCF-7 cells with IC50 value of 8.77 µM, while 31 showed good cytotoxicity against HT-29 cells with IC50 value of 9.18 µM.

Thymoquinone: A novel strategy to combat cancer: A review.

The higher consumption of fruit, herbs, spices, and vegetables is well known and practical strategy to cure human cancers owing to their presence of bioactive compounds. Among these, Nigella sativa is a promising source of bioactive compounds including thymoquinone, monoterpenes, p-cymene and α-piene etc. Thymoquinone has been found effective to inhibit the different cancer stages such as proliferation, migration and invasion. It also acts as anticancer agent against different human cancers such as breast, pancreatic, prostate, blood, oral, bone, head and neck, cervical, liver and lung. It significantly mediated miR-34a up-regulation, enhanced the levels of miR-34a through p53, and down controlled Rac1 expression. Thymoquinone induces apoptosis, regulates the levels of pro- and anti- apoptotic genes. It also has been known to lower the phosphorylation of NF-κB and IKKα/ß and reduces the metastasis as well as also lowered the ERK1/2 and PI3K activities. Thymoquinone inhibits the metastasis through activation of JNK and p38. The present review article highlights the anticancer perspectives of thymoquinone in human by various pathways and use of this compound as diet based therapy has proven new pharmacological agent against several types of cancers.

New Genetic Variation in BCR gene of Major B3a2 Breakpoint BCR-ABL Fusion Gene in Patients with Chronic Myelogenous Leukemia in Yogyakarta, Indonesia

Background: Polymorphic bases in several exons of the BCR gene have been found in several studies of the BCR-ABL fusion gene . Most of the polymorphisms do not have any implications for the primary structure of the BCR-ABL protein. Nucleotide changes are often located in the area close to the fusion region, and therefore may influence primer annealing. Our previous work failed to amplify 15 of 200 samples from BCR-ABL positive chronic myelogenous leukemia (CML) patients using multiplex PCR, the standard method to detect BCR-ABL transcripts used in our institution. The failure was considered due to problems in primer annealing caused by sequence variations. Sequence analysis of BCR-ABL fusion gene breakpoint types in CML patients has never been hitherto performed in Indonesia. Therefore, the aim of this study was to perform sequence analysis of several samples that did not show amplification using the standard method. Methods: Fifteen samples were qualitatively amplified by two-step PCR using inner primers in the 2nd PCR to determine the breakpoint type of the BCR-ABL fusion gene. The 2nd PCR products were used as templates to perform sequence analysis, and the results were compared to those in genbank. Result: Seven and 5 of 15 samples were confirmed as major b3a2 and major b2a2, respectively. One sample featured a combination of b3a2 and b2a2, and 2 samples a combination of b3a2 and b2a2 with an additional fragment at 500bp. Sequence analysis showed 3 sequence variations in the major b3a2 breakpoint. One had been reported earlier (c.3296T>C) but the others (c.3245C>T and c.3359T>C) were novel. Fragments at 500bp were confirmed as b3a2 and similar sequence b3a2 in genbank. Conclusion: This study found two new genetic variations in the BCR gene in BCR-ABL fusion cases.

Cylindroxanthones A-C, three new xanthones and their cytotoxicity from the stem bark of Garcinia cylindrocarpa.

Three new xanthones, cylindroxanthones A-C (1-3), were isolated from the stem bark of Garcinia cylindrocarpa. The structures were established on the basis of spectroscopic analysis. The molecular structure of 1 was unequivocally confirmed by single-crystal X-ray diffraction analysis. These three xanthones were evaluated regarding their cytotoxicity against KB, HeLa S-3, HT-29, MCF-7, and Hep G2 cancer cell lines. Compound 1 exhibited good cytotoxicity against KB cell with IC50 value of 2.36 µM.

The inhibitory activity of aldose reductase in vitro by constituents of Garcinia mangostana Linn.

We investigated aldose reductase inhibition of Garcinia mangostana Linn. from Indonesia. Dichloromethane extract of the root bark of this tree was found to demonstrate an IC50 value of 11.98 µg/ml for human aldose reductase in vitro. From the dichloromethane fraction, prenylated xanthones were isolated as potent human aldose reductase inhibitors. We discovered 3-isomangostin to be most potent against aldose reductase, with an IC50 of 3.48 µM.

20(S)-Ginsenoside Rh2 as aldose reductase inhibitor from Panax ginseng.

The root of Panax ginseng C. A. Meyer (Araliaceae) is a well-known herbal medicine in East Asia. The major bioactive metabolites in this root are commonly identified as ginsenosides. A series of ginsenosides were determined for in vitro human recombinant aldose reductase. This Letter aims to clarify the structural requirement for aldose reductase inhibition. We discovered that only ginsenoside 20(S)-Rh2 showed potent against aldose reductase, with an IC50 of 147.3 µM. These results implied that the stereochemistry of the hydroxyl group at C-20 may play an important role in aldose reductase inhibition. An understanding of these requirements is considered necessary in order to develop a new type of aldose reductase inhibitor. Furthermore, P. ginseng might be an important herbal medicine in preventing diabetic complications.