Evaluation of anti-acne activity of selected Sudanese medicinal plants

Acne vulgaris is the most common skin disease in the world, and the number of antibiotics resistant to acne-inducing bacterial strains has been increasing in the past years. Natural substances from plants are promising candidates to treat this disease. The methanol and 50 % (v/v) ethanol extracts of 29 plant species traditionally used in Sudan for treatment of a variety of diseases were tested in vitro for their potential anti-acne activity. The activities of these extracts were determined using an antibacterial assay against Propionibacterium acnes, a lipase inhibitory assay, and l,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity assay. The results showed that methanol and 50 % ethanol extracts of Terminalia laxiflora Engl & Diels wood exhibited good antibacterial activity (minimum inhibitory concentration 0.13 mg/ml). The 50 % ethanol extracts of Abrus precatorius L. seed, T. laxiflora Engl & Diels and methanol extract of Acacia nilotica (L.) pods showed lipase inhibitory activity more than 70 % at 500 μg/ml. The methanol extracts of A. nilotica (L.) pods showed the best DPPH radical scavenging activity (IC₅₀ 1.32 μg/ml). Total phenolic, flavonoid and total tannin contents of selected plant extracts shown anti-acne activities were investigated. Almost all selected extracts contained phenolic compound. The highest level of flavonoids (38.87 μg/mg) was detected in T. brownii bark, whereas the highest amount of tannin was detected in A. nilotica (L.) bark (88.01 %).     

Screening antiacne potency of Indonesian medicinal plants: antibacterial,lipase inhibition,and antioxidant activities

Indonesian medicinal plants were screened as potential sources of antiacne agents. The screening methods were performed using antibacterial assay against Propionibacterium acnes, lipase inhibitor assay, and antioxidant assay. The results showed that from 40 plant materials extracted with methanol and 50% ethanol in water, Caesalpinia sappan was the best extract based on the combined activities: antibacterial (minimum inhibitory concentration 0.13 mg/ml; minimum bactericidal concentration 0.25 mg/ml), lipase inhibitory [50% inhibitory concentration (IC₅₀) 120.0 μg/ml], and antioxidative (IC₅₀ 6.47 μg/ml). Another prospective extract is Intsia palembanica based on its lipase inhibitory activity (IC₅₀ 4.1 μg/ml) and antioxidant activity (IC₅₀ 3.87 μg/ml). Part of this report was presented at the 58th Annual Meeting of the Japan Wood Research Society, Tsukuba, March 2008     

Antioxidant flavonoids from Epimedium wushanense

Two new flavonoids, wushanicaritin (1) and wushankaempferol (2), along with 24 known flavonoids were isolated from the whole herb of Epimedium wushanense T.S. Ying (Berberidaceae). On the basis of NMR and ESI-MS spectroscopic analysis, structures of compounds 1 and 2 were elucidated as 8-γ-hydroxy-γ,γ-dimethylpropyl-3,5,7-trihydroxy-4′- methoxyflavone and kaempferol 3-O-α-l-[2,3-di-O-β-d-(6-E-p-coumaroyl) glucopyranosyl]-rhamnopyranosyl-7-O-α-l-rhamnopyranoside, respectively. DPPH radical scavenging activity tests indicated that 1 (IC₅₀ 35.3 μM) exhibited antioxidant activity comparable to Vitamin C (IC₅₀ 32.0 μM), while 2 (IC₅₀ 443.7 μM) showed weak activity.     

Sinoscrewtine,an alkaloid with novel skeleton from the roots of Sinomenium acutum

An alkaloid with novel skeleton, sinoscrewtine (1), has been isolated from the roots of Sinomenium acutum. Its structure was established by spectral analysis and X-ray crystallographic study, and its possible biosynthetic pathway was delivered. In vitro experiments, 1 showed weak injurious effects against H₂O₂/Aβ_25–35 induced oxidative injury in PC-12 cells and DPPH radical scavenging activity with IC₅₀ of 32.6 μM.     

Brazilin from Caesalpinia sappan wood as an antiacne agent

In screening experiments for antiacne activity, methanolic and 50% ethanolic extracts of Caesalpinia sappan wood showed the most potent activity out of 28 species of plants extracts. These extracts showed inhibition of Propionibacterium acnes growth, lipase inhibitory activity, and antioxidant activity. In order to isolate the active compound from C. sappan, separation of the extract components was performed by column chromatography and preparative high-performance liquid chromatography (HPLC). Brazilin, protosappanin A, and sappanone B were isolated from methanolic extracts. Brazilin showed better antibacterial activity [minimum inhibitory concentration (MIC) = minimum bactericidal concentration (MBC) = 0.50 mg/ml] than protosappanin A (MIC = MBC = 1.00 mg/ml) and sappanone B (MIC = MBC > 2.00 mg/ml). The 50% inhibitory concentration (IC₅₀) for lipase inhibition was lowest for brazilin (6 μM), which showed strong inhibition compared with protosappanin A (100 μM) and chloramphenicol (677 μM, positive control). The antioxidant activity of brazilin (IC₅₀ 8.8 μM) was not significantly different from protosappanin A (9.1 μM) and (+)-catechin (10.2 μM). The antioxidant activity of brazilin and protosappanin A were higher than sappanone B (IC₅₀ 14.5 μM). Brazilin is considered to have suffi ciently potent activity for use as an antiacne agent.     

12个楸树无性系叶片多酚含量与抗氧化活性

自由基具有强氧化性,机体衰老及多种疾病如肿瘤、炎症、神经退行性疾病、动脉粥样硬化等的诱发促进机制都与自由基有关[1]。自由基的减少,不仅要靠自身的清除系统,还需要外部抗氧化剂的协助。近年来,关于合成抗氧化剂的副作用受到人们更多的关注,因此,寻找安全、高效的植物源类抗氧化剂,已成为食品领域研究的热点。楸树(Catalpa bungei C.A.Mey.)为紫葳科(Bignoniaceae)梓属植物,落叶乔木,《本草纲目》记载楸树树皮、叶具有药     

Antioxidant secoiridoids from fringe tree (Chionanthus virginicus L.)

Recently, a number of studies on health benefits associated with natural compounds have been demonstrated. Phenolics in fruits, vegetables, herbs and spices possess potent antioxidant, anti-inflammatory, antimutagenic and anticarcinogenic activities. The fringe tree (Chionanthus virginicus) is used as a raw material by pharmaceutical industries for the preparation of homeopathy tinctures. The potential antioxidant activities of two secoiridoids from root bark of fringe tree (Chionanthus virginicus L.) were investigated to evaluate their potential value as the natural products for foods or cosmetic applications. In this study, antioxidant activities were measured by 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH·) scavenging, superoxide anion (O ₂ ^·? ) radical scavenging, total antioxidant activity, reducing activity, hydrogen peroxide (H₂O₂) scavenging and ferrous metal chelating activity assays. These secoiridoids, as antioxidants neutralized the activities of radicals and inhibited the peroxidation reactions of linoleic acid emulsion. Total antioxidant activity was measured according to ferric thiocyanate method. Butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and trolox, a water-soluble analog of tocopherol, were used as the reference antioxidant compounds. Ligustroside (3.70 × 10^?3 M) and oleuropein (3.80 × 10^?3 M) showed 71.9, 82.4, 80.7 and 90.4% inhibition on lipid peroxidation of linoleic acid emulsion, at the concentrations of 10 and 20 μg/mL. On the other hand, 20 μg/mL of standard antioxidant such as α-tocopherol (4.64 × 10^?3 M), trolox (7.98 × 10^?3 M), BHA (10.08 × 10^?3 M) and BHT (9.06 × 10^?3 M) exhibited 61.5, 29.8, 74.4 and 71.2% inhibition on peroxidation of linoleic acid emulsion, respectively. In addition, ligustroside and oleuropein had effective DPPH·, ABTS^·+ and superoxide anion radicals scavenging, hydrogen peroxide scavenging, total reducing power and metal chelating on ferrous ions activities. Also, those various antioxidant activities were compared to BHA and BHT, α-tocopherol and trolox that are references antioxidants.     

Four new fluorenone alkaloids and one new dihydroazafluoranthene alkaloid from Caulophyllum robustum Maxim

Four new fluorenone alkaloids, caulophylline A-D (1-4), and one new dihydroazafluoranthene alkaloid, caulophylline E (5) were isolated from the roots of Caulophyllum robustum Maxim. Their structures were elucidated by spectroscopic analysis. Among the isolated alkaloids, Caulophylline E showed good scavenging effects against DPPH radical with IC₅₀ of 39 μM.     

Antioxidant, anti-hyaluronidase and antifungal activities of Melaleuca leucadendron Linn. leaf oils

The present study examined the chemical composition, in vitro antioxidant, anti-hyaluronidase and antifungal activities of essential oils of Melaleuca leucadendron Linn. from Gundih-Central Java, Indonesia in different plant ages of 5, 10 and 15 years old. The Chemical composition of essential oils were analyzed by GC/MS. Twenty-six components were identified, of which 1,8-cineole (49.22–55.04 %), α-terpineol (8.79–10.70 %), d-limonene (5.58–6.39 %), and β-caryophyllene (5.03–7.64 %) were the main compounds in these oils. The antioxidant assay and anti-hyaluronidase assay showed that M. leucadendron leaf oils possess mild antioxidant activity with IC₅₀ between 7.21 and 9.23 mg/ml and anti-hyaluronidase activity with IC₅₀ between 1.94 and 3.03 mg/ml. The antifungal assay showed the effectiveness of these essential oils against Fomitopsis palustris (IC₅₀ 0.12–3.16 mg/ml), Trametes versicolor (IC₅₀ 0.01–0.06 mg/ml), Cladosporium cladosporioides (IC₅₀ 0.03–0.49 mg/ml), and Chaetomium globosum (IC₅₀ 0.06–0.15 mg/ml).     

Isolation of a novel catechin from Bergenia rhizomes that has pronounced lipase-inhibiting and antioxidative properties

An aqueous ethanol extract of Bergenia crassifolia rhizomes strongly inhibited human pancreatic lipase activity and increased scavenging of DPPH free radicals in vitro. Chromatographic separation of this extract led to isolation of the hydrolysable tannins (+)-catechin 3,5-di-O-gallate () and (+)-catechin 3-O-gallate (). This is the first report of the isolation of compound 1 from plant material. This compound strongly inhibited human pancreatic lipase (with an IC₅₀ value of 0.42 μg/ml) and exhibited a remarkable free radical-scavenging ability (with an SC₅₀ value of 1.04 μg/ml). The chemical structures of 1 and 2 were elucidated using MS, NMR and chemical approaches.     

Pistagremic acid,a glucosidase inhibitor from Pistacia integerrima

Pistacia integerrima Stewart in traditionally used as folk remedy for various pathological conditions including diabetes. In order to identify the bioactive compound responsible for its folk use in diabetes, a phytochemical and biological study was conducted. Pistagremic acid (PA) was isolated from the dried galls extract of P. integerrima. Strong α-glucosidase inhibitory potential of PA was predicted using its molecular docking simulations against yeast α-glucosidase as a therapeutic target. Significant experimental α-glucosidase inhibitory activity of PA confirmed the computational predictions. PA showed potent enzyme inhibitory activity both against yeast (IC₅₀: 89.12 ± 0.12 μM) and rat intestinal (IC₅₀: 62.47 ± 0.09 μM) α-glucosidases. Interestingly, acarbose was found to be more than 12 times more potent an inhibitor against mammalian (rat intestinal) enzyme (having IC₅₀ value 62.47 ± 0.09 μM), as compared to the microbial (yeast) enzyme (with IC₅₀ value 780.21 μM). Molecular binding mode was explored via molecular docking simulations, which revealed hydrogen bonding interactions between PA and important amino acid residues (Asp60, Arg69 and Asp 70 (3.11 Å)), surrounding the catalytic site of the α-glucosidase. These interactions could be mainly responsible for their role in potent inhibitory activity of PA. PA has a strong potential to be further investigated as a new lead compound for better management of diabetes.     

Cycloartane Triterpenes from Beesia calthaefolia (Maxim.)

Three new cycloartane triterpenoids (1–3) and two known compounds (4, 5) were isolated from the whole plant of Beesia calthaefolia. Their structures were elucidated by 1D and 2D NMR, HRESIMS and optical rotation spectral data. All isolates were investigated for their inhibitory effects on the classical pathway of the complement system. Among them, compound 4 showed stronger inhibitory activity (IC₅₀ 136.7 μM) than positive control (Rosmarinic acid, IC₅₀ 181.8 μM) while compounds 2 and 3 were moderately active with IC₅₀ value of 206 μM and 200.9 μM. Chemical compound studied in this article: Rosmarinic acid (PubChem CID: 5281792).     

Antioxidative compounds from leaves of Tahongai (<Emphasis Type="Italic">Klienhovia hospita</Emphasis>)

In our effort to find antioxidant agent, we focused on Tahongai (Kleinhovia hospita) which have been used traditionally in Indonesia as medicinal herbal to cure liver disease. Based on the biologically guided fractionation using DPPH radical scavenging assay, eleutherol and kaempferol 3-O-β-d-glucoside was isolated from the leaves of K. hospita. Kaempferol 3-O-β-d-glucoside (1) and eleutherol (2) scavenged the radical with IC₅₀ of 71.4 and 491.8 μM, respectively. In addition, both of the compounds did not exhibit cytotoxicity on HepG2 cells.     

Antioxidant properties and structural analysis of phenolic glucosides from bark of <Emphasis Type="Italic">Populus ussuriensis</Emphasis> Kom.

The methanol (MeOH) extract of Populus ussuriensis Kom. bark was analyzed for antioxidant assessing by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging potential. Among fractions using several solvents, the ethyl acetate (EtOAc) soluble fraction, which showed strong antioxidant activity (IC₅₀ 2.02 ± 0.01 μg/ml), was further purified by Thin layer chromatography (TLC) guided Sephadex LH-20 column chromatography. Three known phenolic glucosides, picein (I), salicortin (II), grandidentatin (III), and that of a new, 2-hydroxycyclohexyl-4′-O-p-coumaroyl-β-d-glucopyranoside (isograndidentatin A), were isolated and their structures were elucidated on the basis of physiochemical and spectroscopic methods. This was the first report of the chemical composition of P. ussuriensis bark. Phenolic glucosides III and IV exhibited strong antioxidant activities, with IC₅₀ values 6.73 ± 0.01 and 6.69 ± 0.01 μM, respectively, comparable to the control (α-tocopherol, IC₅₀ 6.80 ± 0.01 μM). P. ussuriensis bark EtOAc-soluble fraction and compounds III and IV could be used as biopreservatives in food applications as well as for cosmetic and medicinal preparations, to alleviate oxidative stress.     

Japonicasins A and B,two new isoprenylated flavanones from Sophora japonica

Two new flavanones with a C₁₅ isoprenoid group, japonicasins A and B (1 and 2), were isolated from the leaves of Sophora japonica. This is the first report on the presence of the (2E,7E)-6-isopropyl-3,9-dimethyldeca-2,7,9-trien-1-yl group (C₁₅ isoprenoid group) in isoprenylated flavonoids. Their structures were determined by spectroscopic methods, including UV, IR, 1D and 2D NMR, HRESIMS, and CD experiments. In addition, the antioxidant activities of compounds 1 and 2 were determined through DPPH radical scavenging assays. They exhibited potential antioxidant activities, with IC₅₀ values of 35.1 ± 0.8 μM and 88.7 ± 1.1 μM for compounds 1 and 2, respectively.     

Chemical analysis of essential oils of Eupatorium adenophorum and their antimicrobial,antioxidant and phytotoxic properties

Essential oils from inflorescences and roots of Eupatorium adenophorum Spreng (Asteraceae) have been investigated for their antimicrobial, phytotoxic and antioxidant activities. Based on GC–MS, the oil from inflorescences is dominated by sesquiterpenes (55.9 %) with γ-cadinene (18.4 %), γ-muurolene (11.7 %), 3-acetoxyamorpha-4,7(11)-diene-8-one (7.4 %) and bornyl acetate (6.3 %) as the major constituents. The oil obtained from the roots contained both sesquiterpenes (34.3 %) and monoterpenes (32.5 %) in almost equal proportions with E,E-cosmene (19.9 %), γ-muurolene (10.1 %), isothymol (7.5 %), β-cadinene (7.0 %) and α-phellandren-8-ol (5.9 %) as the major constituents. Both oils exhibited significant antifungal activity against five phytopathogenic fungi. The inflorescence oil showed higher antibacterial activity against Klebsiella pneumoniae, while the root oil was more effective against Staphylococcus aureus. The oils strongly inhibited or delayed germination and seedling growth of the weed Phalaris minor in a dose-dependent manner. As evidenced by a DPPH assay, the essential oils also exhibited significant free radical scavenging activity.     

Polyprenylated isoflavanone and isoflavonoids from Ormosia henryi and their cytotoxicity and anti-oxidation activity

A rare naturally-occurring polyprenylated isoflavanone, designated ormosinol (1), and a new isoflavonoid glycoside, named ormosinoside (2), along with 21 known compounds were isolated from the root bark of Ormosia henryi Prain. The structures of compounds 1 and 2 were determined as 5,7,2′,4′-tetrahydroxyl-6,8,5′-tri-(γ,γ-dimethylallyl)isoflavanone and isoprunetin-7-O-β-d-xylopyranosyl-(1 → 6)-β-d-glucopyranoside on the basis of a combination of 1D-, 2D-NMR and mass spectroscopic measurements. Compound 1 showed significant anti-oxidation activity against DPPH radicals (IC₅₀ 28.5 μM) and cancer cell line (A549, LAC, and HepG2) growth inhibitory activity with IC₅₀ ranging from 4.25 to 7.09 μM, while compound 2 found to be inactive to both testing systems.     

Ganoderic acid Df,a new triterpenoid with aldose reductase inhibitory activity from the fruiting body of Ganoderma lucidum

Ganoderic acid Df, a new lanostane-type triterpenoid, was isolated from the fruiting body of Ganoderma lucidum. Its structure was characterized as 7β, 11β-dihydroxy-3, 15, 23-trioxo-5α-lanosta-8-en-26-oic acid by 1D- and 2D-NMR spectra. This compound exhibited potent human aldose reductase inhibitory activity, with an IC₅₀ of 22.8 μM in vitro. A carboxyl group of this compound's side chain is essential for eliciting inhibitory activity because its methyl ester is much less active.     

Antiparasitic antioxidant phenylpropanoids and iridoid glycosides from Tecoma mollis

A radical scavenging guided phytochemical study on the stem bark of Tecoma mollis afforded seven active phenylpropanoid glycosides (1–7), including a new one (4), and one iridoid (8). The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Compounds (1–7) displayed promising antioxidant activity (DPPH assay) in relation to ascorbic acid (positive control). The antimicrobial activity for compounds (1–8) was evaluated against five bacterial and five fungal strains. The isolated compounds exhibited nonselective weak to moderate antimicrobial activity. The highest antileishmanial activity against Leishmania donovani was observed for compound (7) with an IC₅₀ value of 6.71 μg/ml, using pentamidine and amphotericin B as drug controls. Compound (5) exhibited moderate antimalarial activity (45% inhibition) against chloroquine sensitive (D6) clones of Plasmodium falciparum.     

New α-glucosidase inhibitors with p-terphenyl skeleton from the mushroom Hydnellum concrescens

The purpose of this study is to elucidate the bioactive components responsible for the the α-glucosidase inhibitory activity detected in the EtOAc extract of the mushroom Hydnellum concrescens. Two new p-terphenyl derivatives, concrescenins A (1) and B (2), in along with six known compounds thelephantins L (3), I (4), J (5), K (6), dihydroauran-tiacin dibenzoate (7), and curtisian A (8) were isolated from the fruiting bodies of H. concrescens. Their chemical structures were elucidated by NMR experiments. Compounds 1–4 and 6–8 showed the inhibitory activity against α-glucosidase with the IC₅₀ of 0.99, 3.11, 4.53, 18.77, 2.98, 5.16, and 8.34 μM, respectively. Kinetic analysis of α-glucosidase indicated that compounds 1 and 2 inhibited the activity of α-glucosidase in a noncompetitive fashion with a Ki value of 0.02 and 0.21 μM, respectively. In antioxidant evaluation, compounds 1 and 4 showed weak DPPH scavenging activity (EC₅₀ = 82.50 and 161.75 μM) and weak reducing ability (EC₅₀ = 193.57 and 152.94 μM). The current research supports the potential use of mushroom-derived p-terphenyl derivatives for the treatment of diabetes.