•Animal study was performed to investigate the anti-influenza activity of G. lingzhi.•Both oral and intranasal administrations were applied in the animal study.•An in vitro Neuraminidase activity assay was also used to assess inhibition.•The total content of triterpenoids and carbohydrates in the extract were determined.The consumption of mushroom Ganoderma lingzhi (G. lingzhi) is believed to help people fight influenza. However, few scientific studies, particularly in animals, has addressed that. Here, a hot-water extract of G. lingzhi was orally or intranasally administered to mice infected with influenza A virus, following by a 21-day post-infection observation. An in vitro neuraminidase (NA) assay, with four subtypes of NA, was used to assess inhibition. The total content of triterpenoids and carbohydrates in the extract were determined with colorimetric assays. Results showed that intranasal administration of the extract reduced the severe weight loss in infected mice by 55.1%. Oral administration of the extract did not significantly interfere the virus infection. In addition, the extract strongly inhibited NA from influenza virus H1N1 and H5N1. These findings suggest that short-term oral consumption of hot-water extract of G. lingzhi has limited anti-influenza function, which also inform further research for its activity observed.

Tubulin polymerization is an important target for anticancer therapies. Even though the potential of Ganoderma triterpenoids against various cancer targets had been well documented, studies on their tubulin polymerization-stimulating activity are scarce. This study was conducted to evaluate the effect of Ganoderma triterpenoids on tubulin polymerization. A total of twenty-four compounds were investigated using an in vitro tubulin polymerization assay. Results showed that most of the studied triterpenoids exhibited microtuble-stabilizing activity to different degrees. Among the investigated compounds, ganoderic acid T-Q, ganoderiol F, ganoderic acid S, ganodermanontriol and ganoderic acid TR were found to have the highest activities. A structure–activity relationship (SAR) analysis was performed. Extensive investigation of the SAR suggests the favorable structural features for the tubulin polymerization-stimulating activity of lanostane triterpenes. These findings would be helpful for further studies on the potential mechanisms of the anticancer activity of Ganoderma triterpenoids and give some indications on the design of tubulin-targeting anticancer agents.

Recent studies identified Rho-kinase enzymes (ROCK-I and ROCK-II) as important targets that are involved in a variety of diseases. Synthetic Rho-kinase inhibitors have emerged as potential therapeutic agents to treat disorders such as hypertension, stroke, cancer, diabetes, glaucoma, etc. Our study is the first to screen the total ethanol extract of the medicinal mushroom Ganoderma lingzhi with thirty-five compounds for Rho-kinase inhibitory activity. Moreover, a molecular binding experiment was designed to investigate the binding affinity of the compounds at the active sites of Rho-kinase enzymes. The structure–activity relationship analysis was investigated. Our results suggest that the traditional uses of G. lingzhi might be in part due to the ROCK-I and ROCK-II inhibitory potential of this mushroom. Structure–activity relationship studies revealed some interesting features of the lanostane triterpenes that potentiate their Rho-kinase inhibition. These findings would be helpful for further studies on the design of Rho-kinase inhibitors from natural sources and open the door for contributions from other researchers for optimizing the development of natural Rho-kinase inhibitors.

•A green micellar liquid chromatographic method was adopted for assay of NICO and CLD.•The method was successfully extended to quantify both drugs in a coformulated gel.•The method was validated according to ICH Q2R1 Guidelines.A new green micellar liquid chromatographic method was developed and validated for the quantitative estimation of nicotinamide (NICO) and clindamycin phosphate (CLD) in bulk and pharmaceutical gel formulation. The analytes are well resolved in less than 6.0 minutes using micellar mobile phase consisting of 0.10M sodium dodecyl sulfate (SDS), 0.3% triethylamine, and 10% 2-propanol in 0.02M orthophosphoric acid at pH 3.0, running through an Eclipse XDB-C8 column (150 mm × 4.6 mm, 5 μm particle size) with flow rate 1.0 mL/min. The effluent was monitored with diode array detection at 210 nm. The retention times of NICO and CLD were 3.8 minutes and 5.6 minutes, respectively. The method was validated according to the International Conference on Harmonisation (ICH) guidelines in terms of linearity, limit of detection, limit of quantification, accuracy, precision, robustness, and specificity to prove its reliability. Linear correlation was achieved by plotting the peak area of each drug against its concentration. It was found to be rectilinear in the ranges of 1.0–40.0 μg/mL and 0.5–15.0 μg/mL with limits of detection of 0.06 μg/mL and 0.03 μg/mL and limits of quantification of 0.19 μg/mL and 0.09 μg/mL for NICO and CLD, respectively. The method was successfully implemented for the simultaneous determination of the analytes in their bulk powder and combined gel formulation with high % recoveries. The ease of sample treatment facilitates and greatly expedites the treatment with reduced cost and improved accuracy of the procedure.Download high-res image (228KB)Download full-size image

Hericium erinaceus (H. erinaceus) improves the symptoms of menopause. In this study, using ovariectomized mice as a model of menopause, we investigated the anti-obesity effect of this mushroom in menopause. Mice fed diets containing H. erinaceus powder showed significant decreases in the amounts of fat tissue, plasma levels of total cholesterol, and leptin. To determine the mechanism, groups of mice were respectively fed a diet containing H. erinaceus powder, a diet containing ethanol extract of H. erinaceus, and a diet containing a residue of the extract. As a result, H. erinaceus powder was found to increase fecal lipid levels in excreted matter. Further in vitro investigation showed that ethanol extract inhibited the activity of lipase, and four lipase-inhibitory compounds were isolated from the extract: hericenone C, hericenone D, hericenone F, and hericenone G. In short, we suggest that H. erinaceus has an anti-obesity effect during menopause because it decreases the ability to absorb lipids.

The present study aims to reveal the antibacterial potential of the wild mushrooms of Nepal. Despite the recognition of the medicinal potential of the natural resources in this country, a systematic study on the bioactivities of the wild mushrooms is still lacking. Therefore, in an attempt to fill this gap, ethanol extracts of 90 Nepalese wild mushroom samples were tested for antibacterial activity against Staphylococcus aureus and Propionibacterium acnes. Staphylococcus aureus was comparatively more susceptible with Inonotus clemensiae exhibiting the least minimum bactericidal concentration (MBC) of 100 μg/mL. The major compound in I. clemensiae was identified to be hispidin using high resolution liquid chromatography–electron spray ionization mass spectrometry (LC–ESI-MS) and nuclear magnetic resonance (NMR) analyses. Furthermore, the minimum inhibitory concentration (MIC) and MBC values of hispidin were determined to be 25 and 100 µg/mL for S. aureus and P. acnes, respectively. These findings show that the Nepalese wild mushrooms have the potential to be a novel addition to the functional ingredients industry due to their strong antibacterial potential.

The degranulation of basophils stimulated by antigen is one of the allergic mechanisms of immediate hypersensitivity reactions. In a previous study, the β-hexosaminidase release of rat basophilic leukemia (RBL-2H3) cells stimulated by IgE cross-linking was specifically inhibited by ethanol extract of olive milled waste (OMW). OMW is a potential source of triterpenes, which show several biological activities. However, little is known about the effect of triterpenes in OMW on β-hexosaminidase release. Here we investigated anti-allergic triterpenes from the ethanol extract of OMW, and we discuss the structure–activity relationship. We subjected ethanol extract of OMW to activity-guided fractionation; this led to the isolation of five known triterpenes, i.e., maslinic acid (1), oleanolic acid (2), punicanolic acid (3), 2-O-acetylmaslinic acid (4), and epimaslinic acid (5) as well as one new triterpene, 11-oxo-maslinic acid (6). An anti-allergic assay revealed that 2-O-acetylmaslinic acid (4) and 11-oxo-maslinic acid (6) showed anti-allergic activity. Considering the structure–activity relationship of these triterpenes, it appears that the existence of a ketone group at C-11 or an acetyl group at C-2 would influence the anti-allergic activity.

A new, simple isocratic HPLC method was developed and validated for the simultaneous estimation of four vasoactive phytochemicals: ascorbic acid (ASC), rutin (RUT), hesperidin (HSP), and diosmin (DSM) in different pharmaceutical preparations. Separation of the four compounds was achieved in about 8 min on a phenomenex-C18 column (250 mm × 4.6 mm, 5 μm particle size) using a mobile phase consists of 50 mM phosphate buffer (pH 4.0):acetonitrile (75:25, v/v) eluted at 1.0 mL min−1 with diode array detection at 275 nm. Linear correlation was obeyed over the concentration ranges of 2.0–60.0, 1.0–20.0, 2.0–50.0, and 5.0–100.0 μg mL−1 for ASC, RUT, HSP, and DSM, respectively. The developed method is efficient, reproducible and appropriate as a versatile method for quality control of various combinations of these drugs in different pharmaceutical preparations with high values of %recoveries which agreed well with the labeled claim. The method is also a stability-indicating one for DSM in its pure state and single-component tablets. A comparison of the results obtained by the developed method with those of the comparison methods confirmed no significant differences between them with respect to accuracy and precision.

⿢Two new triterpenes have been isolated from G. lingzhi with six known compounds.⿢The structures were determined on the basis of 1D and 2D NMR and HRESIMS.⿢Cytotoxicity against several cancer cell lines, was performed.Further chemical investigation of the metabolites in the fruiting bodies of Ganoderma lingzhi resulted in isolation of eight triterpenes; two of them are new triterpene acid ethyl esters. Their structures were established based on spectroscopic studies and comparison with the known related compounds. The anticancer potential of the isolates were tested with an in vitro cytotoxic assay against five human cancer cell lines (MCF-7, HeLa, HCT-116, Caco-2 and HepG2) and two normal human cell lines (TIG-1 and HF19). Results showed that the new compounds have a strong to moderate selective cytotoxic activity against MCF-7 while they showed moderate to weak activity against HeLa cell line. Potent cytotoxic activities of some of the known isolated compounds are reported for the first time.

The quantitative analysis of organosulfur compounds is important for the quality control of various garlic products along with studying their molecular functionality and nutraceutical properties. In this study, a liquid chromatography-tandem mass spectrometry-selected reaction monitoring (LC-MS/MS-SRM) method with electrospray ionization detection was developed and validated for the rapid, simultaneous quantification of four representative organosulfur compounds in garlic: alliin, S-allyl-L-cysteine, γ-glutamyl-S-allyl-L-cysteine, and allicin. Stable SRM transitions were achieved for these compounds under optimized conditions, and the linear range extended from 1 to 2000 ng/mL. The limits of detection and quantification ranged from 0.003 to 0.058 ng/mL and from 0.01 to 0.19 ng/mL, respectively. Excellent recovery and reproducibility at different spiking levels were achieved. The method was successfully applied to the simultaneous quantification of organosulfur compounds in fresh garlic samples. This highly selective and sensitive LC-MS/MS-SRM method is expected to be a useful tool for studying molecular functionality and the quality control of garlic products.

Mushrooms have garnered immense popularity for their nutritional as well as medicinal values. The therapeutic potential of mushrooms in Nepal, a country well known for its biodiversity and natural medicinal resources, remains largely unstudied. Therefore, this study attempts to unveil the antioxidative properties of Nepalese wild mushrooms. Sixty-two wild mushroom samples were collected from several forests in different parts of Nepal. Ethanol and water extracts of the dried samples were tested for their antioxidative activities using total phenolic content (TPC), oxygen radical absorbance capacity (ORAC) assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and reducing power (RP) assays. Ethanol extracts of samples belonging to the order Hymenochaetales showed significantly high activity in all the assays. Inonotus clemensiae had an exceptionally high TPC of 643.2 mg gallic acid equivalent (GAE)/g extract and also exhibited the lowest EC50 values in DPPH (0.081 mg/mL), ABTS (0.409 mg/mL), and EC0.5 value in reducing power (RP; 0.031 mg/mL) assays. High-performance liquid chromatography (HPLC) analysis of the top ten samples with the highest TPC was done to identify the phenolic compounds in the extracts, followed by liquid chromatography–mass spectrometry (LC–MS) analysis for some unknown compounds. These findings highlight the very strong antioxidative activity of Nepalese mushrooms, and paves the way for further research to explore their economic potential.

•Besides antioxidant activity, three other bioactivities were investigated.•The fruits as well as nine other parts of strawberry were comparatively studied.•The phytochemical profiles of each parts of strawberry were determined.•The strawberry fruits possess potential anti-obesity and skin-lightening effects.•The parts of crown, stolon leaf and flower showed extraordinary activities.The in vitro antioxidant, anti-obesity, anti-allergy and skin-lightening effects of extracts from strawberry fruits (ripe and unripe) and nine other plant parts of Amaou strawberry (Fragaria × ananassa var. Amaou) were comparatively investigated by using the antioxidant assay and inhibition assays of lipase, adipocyte differentiation, β-hexosaminidase release, melanogenesis and tyrosinase. Their total phenolic content and the main phenolic compounds were also determined. The ripe strawberry fruits were found to possess potential anti-obesity and skin-lightening effects. The ethanol extracts from unripe strawberry fruits and several other parts like the crown, stolon leaf and flower showed more strong activities in the bioactivity assays conducted. The phytochemical profile varied among extracts from various parts of the plant. Ellagic acid was found in every part of the strawberry plant except the root. Our study provides valuable evidence that strawberry fruit is a food with potential anti-obesity and skin-lightening functions. The findings also support that several inedible parts of the strawberry plant have great potential to be used as the ingredients of functional food products.

Semisynthetic reactions were conducted on oleanolic acid, a common plant-derived oleanane-type triterpene. Ten rationally designed derivatives of oleanolic acid were synthesized based on docking studies and tested for their topoisomerase I and IIα inhibitory activity. Semisynthetic reactions targeted C-3, C-12, C-13, and C-17. Nine of the synthesized compounds were identified as new compounds. The structures of these compounds were confirmed by spectroscopic methods (1D, 2D NMR and MS). Five oleanolic acid analogues (S2, S3, S5, S7 and S9) showed higher activity than camptothecin (CPT) in the topoisomerase I DNA relaxation assay. Four oleanolic acid analogues (S2, S3, S5 and S6) showed higher activity than etoposide in a topoisomerase II assay. The results indicated that the C12–C13 double bond of the oleanolic acid skeleton is important for the inhibitory activity against both types of topoisomerases, while insertion of a longer chain at either position 3 or 17 increases the activity against topoisomerases by various degrees. Some of the synthesized compounds act as dual inhibitors for both topoisomerase I and IIα.

The loquat, Eriobotrya japonica Lindl. (Rosaceae), is a small tree native to Japan and China that is widely cultivated for its succulent fruit. Its leaves are used as an ingredient of a tasty tea called “Biwa cha” in Japanese. The anti-osteoporosis effects of the leaves of loquat in vitro and in vivo have been investigated. After 15 days of feeding normal diet or diet supplemented with 5% loquat leaves, the body weight, viscera weights, and bone mineral density (BMD) of both groups of eight ovariectomized (OVX) mice were compared. The result showed that the loss of BMD in loquat-fed mice was significantly prevented in three parts of the body, especially in the trabecular bone of the head (P < 0.05), abdomen (P < 0.01), and lumbar (P < 0.05) compared to the control group. No hypertrophy in the uterus by the loquat leaves diet was observed. The effect of the extract (447.25 g) prepared from the dried leaves of loquat (2.36 kg) was further studied on RANKL-induced osteoclast differentiation and cell viability. The extract suppressed the differentiation of osteoclasts under 50, 125, 250, and 500 μg/mL. Through bioactivity-guided fractionation, ursolic acid (1) was isolated and inhibited osteoclast differentiation under 4 and 10 μg/mL. It was concluded that loquat leaves possess the potential to suppress ovariectomy-induced bone mineral density deterioration.

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.

•Tripeptides with a proline C-terminus were virtually screened for ACE inhibition.•16 peptides with drug-like properties, low in vitro IC50 values were identified.•14 peptides were first reported for the activity.•L- but not d-form amino acid is proven to be essential for inhibitory activity.Currently, peptides and peptidomimetics are the main focus in attempts to identify inhibitors of angiotensin-converting enzyme (ACE), the dipeptidyl carboxypeptidase that causes blood vessels to constrict and blood pressure to increase. This study was conducted to identify the most potent ACE-inhibitory tripeptides with a proline C-terminus, using a novel three-step (tautomerization-docking-ADME simulation) virtual screening process and in vitro assays. Sixteen candidates were identified, and their IC50 values ranged from 5.6 to 274.4 μM. ACE inhibition activity for 14 of the 16 tripeptides was reported for the first time. We also found that changing from the L-form to the D-form of the amino acid at the amino and carboxyl termini resulted in a decrease of inhibition, but a greater decrease was observed for C-terminal changes. With low IC50 values and high-predicted bioavailability, the peptides identified by our protocol are comparable in terms of ACE-inhibition to those derived from costly and time-consuming wet screening. Our in vitro and docking results showed that the configuration of the C-terminus is a critical parameter contributing to the inhibitory activity of tripeptides with proline at this position. These findings will contribute to the use of simulation tools for rational drug design, especially for ACE inhibitors.

A series of lanostane-type triterpenoids, identified as ganoderma alcohols and ganoderma acids, were isolated from the fruiting body of Ganoderma lingzhi. Some of these compounds were confirmed as active inhibitors of the in vitro human recombinant aldose reductase. This paper aims to explain the structural requirement for α-glucosidase inhibition. Our structure–activity studies of ganoderma alcohols showed that the OH substituent at C-3 and the double-bond moiety at C-24 and C-25 are necessary to increase α-glucosidase inhibitory activity. The structure–activity relationships of ganoderma acids revealed that the OH substituent at C-11 is an important feature and that the carboxylic group in the side chain is essential for the recognition of α-glucosidase inhibitory activity. Moreover, the double-bond moiety at C-20 and C-22 in the side chain and the OH substituent at C-3 of ganoderma acids improve α-glucosidase inhibitory activity.These results provide an approach with which to consider the structural requirements of lanostane-type triterpenoids from G. lingzhi. An understanding of these requirements is considered necessary in order to improve a new type of α-glucosidase inhibitor.

Bamboo is intricately associated with human activity, and its usefulness is well known. For example, its roots and leaves have been used as medicinal products. Also, studies on the medicinal properties of bamboo leaves have shown antioxidant, anticancer, and antibiotic properties. In this study, we determined that the dichloromethane soluble of the methanol extract from the bamboo shoot skin (Phyllostachys pubescens) inhibited the growth of Staphylococcus aureus. The active constituents were isolated and identified as stigmasterol and dihydrobrassicasterol by NMR and mass spectrometry. These compounds inhibited the growth of S. aureus and Escherichia coli. Also, from the standpoint of structure–activity relationships, the activities of these phytosterols depend on their side chain structures. These findings indicate that the extracts of bamboo shoot skins as well as its active compounds in the skins are potentially useful as antibacterial materials.

For quantitative determination of 5 triterpenoid constituents, including one ganoderma alcohol (ganodermatriol) and four ganoderma acids (ganoderic acid TR, DM, A, and D), in the products of Ganoderma lucidum, an analytical system was developed using high-performance liquid chromatography. The mobile phase was a linear gradient of 2% AcOH/H2O–CH3CN, and the elution profile was monitored at 243 and 252 nm for ganoderma alcohols and acids, respectively. This system was applied to a quantitative determination of the constituents in the different stage of G. lucidum (BMC9049 strain). The analytical results indicated that the quantity and composition of these triterpenoids differed appreciably among various stages. The stage that showed the highest concentration of ganoderic acid DM and TR also showed the strongest 5α-reductase inhibitory activity. This stage (stage 5 of 6) is thus the prime stage for harvesting this strain. Further, the contents of 5α-reductase inhibitors such as ganoderic acid TR and DM in G. lucidum extracts could be a very useful indicator to assess their 5α-reductase inhibitory activity and verify their potency.Highlights► We develop the HPLC method for evaluating the 5α-reductase inhibitory potency of Ganoderma lucidum. ► Stage 5 is the prime stage for harvesting G. lucidum. ► The contents of ganoderic acid TR and DM in G. lucidum extracts could be a very useful indicator.

The golden oyster mushroom Pleurotus citrinopileatus is a popular edible mushroom with multifunctional biological activities, but there are a limited number of previous studies on its chemical composition. This is the first report of the isolation of glucosylceramide with antimicrobial activity from the fruiting body of this mushroom. This compound was identified as 1-O-β-d-glucopyranosyl-(2S,3R,4E,8E)-2-[(2R)-2-hydroxyhexadecanoylamino]-9-methyl-4,8-octadecadiene-1,3-diol. The IC50 value of this compound for the growth of Escherichia coli and Staphylococcus aureus was 275.1 μM (200 μg/ml) and 323.2 μM (235 μg/ml), respectively.

In an effort to find a new whitening agent, we have found that the methanol extract of the dried skin of Allium cepa showed inhibition of melanin formation. Bioassay-guided fractionation led to the isolation of quercetin (1) and quercetin 4’-O-β-glucoside (3) from A. cepa as the inhibitors of melanin formation in B16 melanoma cells with IC50 values of 26.5 and 131 μM, respectively. In addition, we evaluated the effect of some quercetin derivatives, such as isoquercitrin (2), quercetin 3,4’-O-diglucoside (4), rutin (5) and hyperin (6) on B16 melanoma cells. These quercetin derivatives did not show any inhibition of melanin formation. Furthermore, the ORAC values of compounds 1–6 were 7.64, 8.65, 4.82, 4.32, 8.17 and 9.34 μmol trolox equivalents/μmol, respectively. Dried skin of red onion showed inhibitory activity against melanin formation in B16 melanoma cells, as well as antioxidant properties.

A series of lanostane-type triterpenoids, known as ganoderma acids were isolated from the fruiting body of Ganoderma lucidum. Some of these compounds were identified as active inhibitors of the in vitro human recombinant aldose reductase. To clarify the structural requirement for inhibition, some structure–activity relationships were determined. Our structure–activity studies of ganoderma acids revealed that the OH substituent at C-11 is an important feature and the carboxylic group in the side chain is essential for the recognition of aldose reductase inhibitory activity. Moreover, double bond moiety at C-20 and C-22 in the side chain contributes to improving aldose reductase inhibitory activity. In the case of ganoderic acid C2, all of OH substituent at C-3, C-7 and C-15 is important for potent aldose reductase inhibition. These results provide an approach to understanding the structural requirements of ganoderma acids from G. lucidum for aldose reductase inhibitor. This understanding is necessary to design a new-type of aldose reductase inhibitor.

This study examined the antibacterial activity of moso bamboo shoot skin (Phyllostachys pubescens). Bamboo shoot skin itself and its dichloromethane extract had antibacterial activity against Staphylococcus aureus. Results suggest the possibility of effective utilization of antibacterial materials from bamboo shoot skins that are mainly discarded at present.

Pleurotus citrinopileatus Singer has recently become a popular delicacy in East Asian countries. We prepared a methanol extract, soluble fractions from the methanol extract, and a hot water extract of the fruiting bodies of P. citrinopileatus. The biological activities such as melanin biosynthesis inhibition, tyrosinase inhibition, antioxidant activities [1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, oxygen radical absorbance capacity (ORAC), and superoxide dismutase (SOD)-like activity], antibacterial activities, and antihyaluronidase activities of these extracts were evaluated. We found that the n-hexanesoluble, diethyl ether-soluble, and ethyl acetate-soluble fractions exhibited melanin biosynthesis inhibition in B16 melanoma cells, as well as antioxidant (ORAC) and antibacterial activities. However, the n-butanol-soluble and water-soluble fractions and the methanol and hot water extracts exhibited antioxidant (DPPH radical scavenging, SOD-like activity) and antihyaluronidase activities. These results indicate that the fruiting bodies of P. citrinopileatus have the potential to be used as an ingredient in skin cosmetics.

In the course of searching for new materials to use as whitening agents, we screened 19 methanol extracts prepared from 14 medicinal plants from Central Kalimantan province, Indonesia. The screening methods used were the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assay, a tyrosinase inhibition assay, and a melanin formation inhibition assay using B16 melanoma cells. The extracts of Willughbeia coriacea (bark part of aerial root), Phyllanthus urinaria (root), Eleutherine palmifolia (bulb), Eusideroxylon zwageri (seed), Dendrophthoe petandra (aerial root), Passiflora foetida (stem), and Vitex pinnata (root) showed DPPH radical-scavenging activity of more than 70% at 100 µg/ml. The extracts of W. coriacea (bark part of aerial root), P. urinaria (root), and D. petandra (aerial root) showed tyrosinase inhibitory activity of more than 40% using l-tyrosine as a substrate at 500 µg/ml. The extracts of W. coriacea (bark part of aerial root) and D. petandra (aerial root) showed tyrosinase inhibitory activity of more than 40% using l-DOPA as a substrate at 500 µg/ml. The extracts of W. coriacea (bark part of aerial root, 200 µg/ml), Glochidion philippcum (aerial root, 200 and 300 µg/ml), E. palmifolia (bulb, 50 µg/ml), E. zwageri (seed, 100 µg/ml), D. petandra (aerial root, 200 µg/ml), Lansium domesticum (bark, 25 µg/ml), P. foetida (stem, fruit, 300 µg/ml), and Solanum torvum (root, 300 µg/ml) strongly inhibited the melanin production of B16 melanoma cells without significant cytotoxicity. These findings indicate that some medicinal plants from Central Kalimantan are potential ingredients for skin-whitening cosmetics if their safety can be confirmed.

A geranylated chalcone was isolated from leaves of Artocarpus incisus and it showed potent 5α-reductase inhibitory activity.

•32 triterpenoids were assayed for ACE inhibition effects.•In vitro IC50 values ranged from 0.194 to 0.941 mM.•Structure–activity relationship was shown for the first time.•Inhibition activities were determined as uncompetitive and non-competitive.Many triterpenoids have shown ability to inhibit hydrolyzing activity of angiotensin-converting enzyme; however, there has been no report about the structure–activity relationship and inhibition patterns of these compounds. In this study, 32 lanostane-type triterpenoids derived from Ganoderma lingzhi were assayed to determine the structural features involved in the observed inhibition effects. In silico and in vitro experiments were also used to determine the kinetics of the reaction. Fifteen compounds showed measurable in vitro IC50 values ranging from 0.194 to 0.941 mM. It was shown that carboxyl groups play an important role in inhibiting the enzyme; further, a hydroxyl group or carbonyl group at either C7 or C15 increases the inhibition rate, and a double bond at C24,25 decreases the activity. Based on the docking data we speculated that triterpenoids could not fit into the active site of the enzyme; therefore, the inhibition mode could not be competitive. Dixon plotting showed that the inhibition patterns should be uncompetitive and non-competitive instead.Download full-size image

In searching for a new material made from natural resources that could be used as a whitening agent, we focused on the plants used for skin treatment by the native people of East Kalimantan. The methanol extract of the leaves of Eupatorium triplinerve Vahl showed antimelanogenesis activity in a melanin biosynthesis assay. By activity-guided fractionation, 7-methoxycoumarin (1) was isolated as an active compound. The IC50 of 1 on mushroom tyrosinase was 2360 μM (L-tyrosine was used as the substrate) and above 2840 μM (L-DOPA was used as the substrate), respectively. Regarding melanin formation inhibition in B16 melanoma cells, the IC50 of 1 was 1780 μM with 83% cell viability at IC50. Based on these results, we validated that the leaf extract is in line with the traditional use of the Dayak tribe in East Kalimantan.

α-Glucosidase inhibitor has considerable potential as a diabetes mellitus type 2 drug because it prevents the digestion of carbohydrates. The search for the constituents reducing α-glucosidase activity led to the finding of active compounds in the fruiting body of Ganoderma lucidum. The CHCl3 extract of the fruiting body of G. lucidum was found to show inhibitory activity on α-glucosidase in vitro. The neutral fraction, with an IC50 of 88.7 μg/ml, had stronger inhibition than a positive control, acarbose, with an IC50 of 336.7 μg/ml (521.5 μM). The neutral fraction was subjected to silica gel column chromatography and repeated p-HPLC to provide an active compound, (3β,24E)-lanosta-7,9(11),24-trien-3,26-diol (ganoderol B). It was found to have high α-glucosidase inhibition, with an IC50 of 48.5 μg/ml (119.8 μM).

Our previous results elucidated that the leaves of Eriobotrya japonica possessed the potential to suppress ovariectomy-induced bone mineral density deterioration, and ursolic acid, the major bioactive component in these leaves, suppressed the osteoclast differentiation. The aim of this study was to discover more candidates for development of novel antiosteoclastogenesis agents from the leaves of E. japonica. Phytochemical analysis following a cell-based osteoclastic tartrate-resistant acid phosphatase (TRAP) activity assay revealed 11 more compounds with a potent antiosteoclastogenesis effect. The potency of ursane-type triterpenoids from the leaves of E. japonica prompted us to investigate the structure–activity relationships underlying their antiosteoclastogenesis. The results revealed that both the hydroxyl group at C-3 and the carboxylic group at C-17 played indispensable roles in the antiosteoclastogenesis activity of ursane-type triterpenoids. The configuration at C-3 (a beta-form of the hydroxyl group) was found to be important for this activity. While introducing a hydroxyl group at C-19 increased the inhibitory activity of ursane-type triterpenoids carrying an alpha-form hydroxyl group at C-3. The bioactivity analyses of ursolic acid and oleanolic acid demonstrated that the antiosteoclastogenesis effect of ursolic acid may be related to different positions of the C-29 and C-30 methyl groups on the E-ring, since oleanolic acid showed limited activity. The addition of a hydroxyl group at C-2 would dramatically improve the inhibition of oleanane-type triterpenoids. Collectively, these findings could provide important clues for the improvement of multi-targeted antiosteoclastogenesis agents from the leaves of E. japonica.Download high-res image (167KB)Download full-size image