Eurysterols A and B, cytotoxic and antifungal steroidal sulfates from a marine sponge of the genus Euryspongia

Two new steroidal sulfates, eurysterols A (1) and B (2), were isolated from an undescribed marine sponge of the genus Euryspongia collected in Palau. The structures of the new compounds were assigned by NMR spectroscopic data interpretation. Compounds 1 and 2 showed cytotoxicity against human colon carcinoma (HCT-116) cells with IC50 values of 2.9 and 14.3 microg/mL, respectively, and exhibited antifungal activity against amphotericin B-resistant and wild-type strains of Candida albicans with MIC values, in turn, of 15.6 and 62.5 microg/mL.     

Bioactivity studies on Cassia alata Linn. leaf extracts

The hexane, chloroform and ethyl acetate extracts of the leaves of Cussia alata Linn. were tested for their antimutagenic, antifungal, analgesic, antiinflammatory and hypoglycaemic activities. At a dosage of 5 mg/20 g mouse, the hexane extract was analgesic as it reduced the number of squirms induced by acetic acid by 59.5%. Both the hexane and EtOAc extracts exhibited antiinflammatory activity at a dosage of 5 mg/20 g mouse with a 65.5% and 68.2% decrease in carrageenan-induced inflammation, respectively. The chloroform extract was antimutagenic, at a dosage of 2 mg/20 g mouse, with a 65.8% inhibition in the mutagenicity of tetracycline. It was also the most active against Trichophyton mentagrophytes, at a concentration of 50 mg/mL but it had no activity against Candida albicans. The hexane and EtOAc extracts showed some activity against both organisms, with the EtOAc extract being more active against C. albicans. The EtOAc extract was hypoglycaemic. At a dosage of 5 mg/20 g mouse, it decreased the blood sugar level of mice by 58.3%. Pharmacological studies showed that all extracts caused an immediate decrease in motor activity, enophthalmus, hyperemia, micturition and diarrhoea. At a dosage of 150 mg/20 g mouse, the EtOAc extract caused paralysis, screen grip loss and enophthalmus accompanied by drooping and closure of the eyelids.     

Antifungal substances against pathogenic fungi, talaroconvolutins, from talaromyces convolutus

The dichloromethane extract of Talaromyces convolutus cultivated on barley exhibited antifungal activity against Candida albicans. In the course of a search for the active compounds, four new tetramic acid derivatives, talaroconvolutins A (1), B (2), C (3), and D (4), were isolated along with ZG-1494alpha (5), and mitorubrin derivatives. The structures of talaroconvolutins A-D (1-4) were established on the basis of spectroscopic and chemical investigations and chemical correlations. The antifungal activity of the talaroconvolutins against the pathogenic fungi Aspergillus fumigates, Aspergillus niger, C. albicans, and Cryptococcus neoformans was determined.     

Biologically active traditional medicinal herbs from Balochistan, Pakistan

The biological activities of the following four important medicinal plants of Balochistan, Pakistan were checked; Grewia erythraea Schwein f. (Tiliaceae), Hymenocrater sessilifolius Fisch. and C.A. Mey (Lamiaceae), Vincetoxicum stocksii Ali and Khatoon (Asclepiadaceae) and Zygophyllum fabago L. (Zygophyllaceae). The methanolic extracts were fractionated into hexane, ethyl acetate, chloroform, butanol and water. The antifungal and antibacterial activities of these plants were determined against 12 fungal and 12 bacterial strains by agar well diffusion and disk diffusion assays. The extract of Zygophyllum fabago was found to be highly effective against Candida albicans and Escherichia coli. The extract of Vincetoxicum stocksii was also found to be significantly active against Candida albicans, Bacillus subtilis and Bacillus cereus. Extracts of Hymenocrater sessilifolius and Grewia erythraea showed good activity only against Pseudomonas aeruginosa.     

Synthesis and antifungal activity of natural product-based 6-alkyl-2,3,4,5-tetrahydropyridines

Seven 6-alkyl-2,3,4,5-tetrahydropyridines (5a-5g) that mimic the natural piperideines that were recently identified in fire ant venom have been synthesized. Compounds 5c-5g with C-6 alkyl chain lengths from C14 to C18 showed varying degrees of antifungal activities, with 5e (6-hexadecyl-2,3,4,5-tetrahydropyridine) and 5f (6-heptadecyl-2,3,4,5-tetrahydropyridine) being the most active. Compound 5e exhibited minimum fungicidal concentrations of 3.8, 15.0, 7.5, and 7.5 μg/mL against Cryptococcus neoformans, Candida albicans, Candida glabrata, and Candida krusei, respectively. The antifungal activities of these compounds appear to be associated with the C-6 side chain length. This study represents the first effort to evaluate antifungal activities of synthetic analogues of the newly identified fire ant venom alkaloids.     

猫爪草提取物体外抗菌活性研究

目的:对猫爪草提取物进行了体外抗菌实验,测定其抑菌圈直径和最低抑菌浓度值(MIC),探讨其抗菌活性。方法:采用牛津杯法探讨猫爪草提取物对常见的4种细菌的抑制作用,同时采用微量二倍稀释法测定其对不同供试菌株的最低抑菌浓度(MIC)和最低杀菌浓度(MBC)。结果:猫爪草提取物对不同供试菌种均有一定的抑制作用,且随着浓度的升高,其抑菌活性有逐渐增强的趋势。对金黄色葡萄球菌、绿脓杆菌、大肠杆菌、痢疾杆菌的最低抑菌浓度分别为15.6、31.2、31.2、31.2μg/mL。结论:猫爪草提取物具有较强的抗菌活性,作为抗菌药具有一定的利用价值。     

Methanol adduct of puupehenone, a biologically active derivative from the marine sponge Hyrtios species.

A methanol adduct of puupehenone (1), 15alpha-methoxypuupehenol (2), an artifact resulting from the action of MeOH on puupehenone, was isolated during purification of the CH(2)Cl(2) extract of the New Caledonian marine sponge Hyrtios sp., as the major constituent. Its chemical structure was elucidated by 2D NMR experiments. Compound 2 displayed similar antimicrobial and antifungal activity as puupehenone and a lower cytotoxic activity toward KB cells with ED(50) values of 6 and 0.5 microg/mL, respectively. Compound 2 was slightly more active against three strains of Plasmodium falciparum than puupehenone.     

Isolation and structural elucidation of proline-containing cyclopentapeptides from an endolichenic Xylaria sp

Two new cyclic pentapeptides (1 and 2) and the known blazein (3), ganodesterone (4), ergosterin (5), cerevisterol (6), 24-methylcholesta-4,6,8(14),22-tetraen-3-one (7), 5,8-epidioxyergosta-6,22-dien-3-ol (8), 16-α-d-mannopyranosyloxyisopimar-7-en-19-oic acid (9), and 16-hydroxy isopimar-7-en-19-oic acid (10) have been isolated from the crude extract of an endolichenic Xylaria sp. The structures of 1 and 2 were elucidated primarily by NMR and MS methods. The absolute configurations of 1 and 2 were assigned using Marfey's method on their acid hydrolysate. Compounds 1-10 were evaluated for activity against fungi and for synergistic antifungal activity. Compound 1 showed synergistic antifungal activity against Candida albicans SC5314 with 0.004 μg/mL ketoconazole.     

Screening of solanum surrattense for antibacterial, antifungal, phytotoxic and haemagglutination

Objective

Plants produce a variety of useful bioactive materials that have been used to cure different ailments of human beings. With the same idea in mind, the crude methanolic extract and various fractions of Solanum surrattense were screened for antibacterial, antifungal, phytotoxic and heamagglutination activities.

Methods

Standardized assays were followed for the determination of antibacterial, antifungal phytotoxic and heamagglutination activity.

Results

The results of the antibacterial showed that crude methanolic extract was significantly active against Staphylococcus aureus (86%) The n-hexane fraction showed good activity against Pseudomonas aerogenosa (66.6%) and Bacillus subtilus (66.6%). The crude methanolic extract and various fractions were inactive against all test fungi. The crude methanolic extract, n-hexane, CHCI₃ and aqueous fractions showed moderate phytotoxic activities of 46.67%, 40.00%, 33.34% and 33.34% respectively at 1000 μg/mL. The crude methanolic extract and various fractions S. surrattense were unable to agglutinate RBCs of the human blood indicating that this species lack phytolectins.

Conclusion

The test sample showed significant antibacterial activity, no antifungal and heamagglutination activity while moderate phytotoxic was observed against Lemna minor L.     

地锦草有效部位对真菌琥珀酸脱氢酶活性的影响

目的初步研究维吾尔药材地锦草有效部位体外抗真菌作用,研究地锦草有效部位对红色毛癣菌琥珀酸脱氢酶活性的影响,探讨其抗真菌作用机制。方法地锦草醇提物经大孔吸附树脂分离得6个洗脱部位,分别为部位一、部位二、部位三、部位四、部位五及部位六;采用微量液基稀释法测定各部位体外最低抑菌浓度（MIC）值,确定其最有效部位和敏感菌株;药物干预毛癣菌后分离菌体,按试剂盒要求处理样品,利用硫酸甲酯吩嗪（PMS）反应法,测定地锦草有效部位对红色毛癣菌琥珀酸脱氢酶活性的作用。结果地锦草各洗脱部位中,部位六的抗真菌活性最为显著,其对红色毛癣菌（T．rubrum）的平均MIC为149μg／mL,对石膏样毛癣菌（T．mentagrophytes）的平均MIC为149μg／mL,对其他皮肤癣菌平均MIC为192μg／mL,对4种念珠菌的平均MIC均为416μg／mL。不同浓度的地锦草有效部位均可降低红色毛癣菌琥珀酸脱氢酶活性（P〈0．01）。结论地锦草不同提取部位对试验菌株的生长均具有抑制作用,其中部位六尤为显著,对浅部致病真菌有较强的抑制作用,定为有效部位。地锦草有效部位抗真菌机制可能与抑制琥珀酸脱氢酶的活性有关。     

Antifungal activity of steroidal glycosides from Yucca gloriosa L

The antifungal activity of a crude steroidal glycoside extract from Yucca gloriosa flowers, named alexin, was investigated in vitro against a panel of human pathogenic fungi, yeasts as well as dermatophytes and filamentous species. The minimal inhibitory concentration (MIC) was determined by an agar dilution method. Alexin had a broad spectrum of antifungal activity, found to reside entirely in the spirostanoid fraction. The major tigogenyl glycosides, yuccaloeside B and yuccaloeside C, exhibited MICs between 0.39 and 6.25 microg[sol ]mL for all the tested yeast strains except for two (C. lusitaniae and C. kefyr). They were also active against several clinical Candida isolates known to be resistant to the usual antifungal agents. The MICs for the dermatophytes were between 0.78 and 12.5 microg[sol ]mL. The most sensitive filamentous species was A. fumigatus (MIC = 1.56 microg[sol ]mL). For most of the strains, the MICs of both glycosides were similar to those of the reference antifungal agent.     

In vitro antifungal activity of extract and plumbagin from the stem bark of Diospyros crassiflora Hiern (Ebenaceae)

In this study the methanol/dichloromethane (1:1) extract and plumbagin isolated from extract of stem barks of Diospyros crassiflora were tested for their antifungal activity against 12 strains of yeast pathogens and filamentous fungi: Candida albicans, Candida glabrata, Candida krusei, Candida tropicalis, Cryptococcus neoformans, Aspergillus niger, Aspergillus flavus, Alternaria sp., Cladosporium sp., Geotrichum candidum, Fusarium sp. and Penicillium sp. The growth of all fungi strains tested was inhibited by the extract and plumbagin. The diameter of inhibition zones varied from 12 to 18 mm and from 21 to 35 mm for the extract and plumbagin, respectively. The MIC values ranged from 12.5 to 25 mg/mL for the extract and 0.78-3.12 microg/mL for plumbagin. It is therefore suggested that extracts from the stem bark of Diospyros crassiflora could be used traditionally in the treatment of fungal infections. Compared with ketoconazole used as a standard antifungal, plumbagin could be considered as a promising antifungal agent.     

四味蒙药体外抗真菌实验研究及超微结构观察

目的观察四味蒙药水提及醇提物对红色毛癣菌、须癣毛癣菌、犬小孢子菌、白色念珠菌和糠秕马拉色菌的体外抗真菌作用,并观察大花葵水提物对白色念珠菌和糠秕马拉色菌超微结构的改变。方法采用试管内药基法测定四味蒙药水、醇提物的最小抑菌浓度(MIC),扫描电镜下观察大花葵水提物作用后白色念珠菌和糠秕马拉色菌超微结构的变化。结果四种蒙药的水、醇提物分别在不同浓度时对受试菌种有较强的抑制作用,且大花葵水、醇提物对红色毛癣菌、须癣毛癣菌、犬小孢子菌的MIC为8.3 g/L。大花葵水提物对白色念珠菌和糠秕马拉色菌的MIC分别为50 g/L、12.5 g/L。经蒙药作用后,在扫描电镜下观察白色念珠菌和糠秕马拉色菌表面出现皱缩、剥脱、裂纹等改变。结论 MIC和超微结构改变提示四味蒙药能有效抑制真菌,为其抗真菌作用机制的研究提供了线索。     

Acetylenic acids inhibiting azole-resistant Candida albicans from Pentagonia gigantifolia

Antifungal bioassay-guided isolation of the ethanol extract of the roots of Pentagonia gigantifolia yielded 6-octadecynoic acid (1) and the new 6-nonadecynoic acid (2). Compounds 1 and 2 inhibited the growth of fluconazole-susceptible and -resistant Candida albicans strains. Their antifungal potencies were comparable to those of amphotericin B and fluconazole. Of particular significance is the low cytotoxicity and specific activity of 1 and 2 against C. albicans.     

The antimicrobial activity of roots of Jatropha podagrica (Hook)

Hexane, chloroform and methanol extracts of the rootwood and rootbarks of Jatropha podagrica were studied for their antimicrobial activity against 18 organisms. All the extracts exhibited some broad spectrum antibacterial activity, at a concentration of 20 mg/mL. The hexane extracts were generally more active than the chloroform and methanol extracts. The hexane extract of the yellow rootbark was the most active of all the extracts and its activity was comparable to that of gentamycin but better with regard to the control of S. aureus and B. cereus. Three of the extracts, hexane extract of the yellow rootbark and hexane and methanol extracts of the rootwood showed moderate antifungal activity against the yeast fungus, Candida albicans.     

羽苔素E体外抗真菌活性及逆转氟康唑耐药的初步研究

 目的评价白色念珠菌对羽苔素E的体外敏感性,并观察羽苔素E和氟康唑合用对白念敏感株和耐药株的联合抗真菌作用。方法采用微量稀释法,测定15株白念敏感株和4株白念耐药株对羽苔素E的敏感性,以最低抑菌浓度(MIC)表示。同时观察羽苔素E与氟康唑合用对白念敏感株和耐药株的联合抗真菌作用。结果羽苔素E对敏感株的MIC值为16 mg·L^-1,对耐药株的MIC值与敏感株基本一致。羽苔素E与氟康唑合用,对敏感株和耐药株分别表现出相加和协同的抗真菌活性,并明显减少氟康唑的用量。结论羽苔素E具有中等的抗真菌活性,与氟康唑合用对耐药菌株表现出协同的抗真菌作用,提示羽苔素E有较好的抗真菌作用并有逆转氟康唑耐药的潜力。     

Anticandidal Activity of Extracts and a Novel Compound,Amnomopin, Isolated From Petriella setifera

A novel triterpenoidal compound named ‘amnomopin’ (3β‐diglucoside‐5,12‐28‐oic acid), which is named IUPAC as 3‐O ‐(2′ ? 1″diglucoside)1,2,3,4,4a,5,6,6a,6b,7,9,10,11,12,12a,12b,13,14b‐octadecahydro‐10‐hydroxy‐2,2,6a,6b,9,9,12a‐heptamethylpicene‐4a‐carboxylic acid, was isolated from the extract Petriella setifera . The total alcoholic extract of P. setifera showed a great activity against clinically isolated Candida species, including Candida albicans , Candida dubliniensis , Candida famata , Candida glabrata , Candida inconspicua , Candida kefyr , Candida krusei , Candida norvegensis , Candida parapsilosis and Candida tropicalis . Also, the new compound amnomopin was active against all the investigated Candida species. The highest anticandidal activity of P. setifera extract was obtained against C. kefyr (22.6 ± 1.5 mm), C. albicans and C. norvegensis (21.3 ± 0.63 mm) and C. krusei (20.6 ± 1.5 mm). Moreover, the minimum inhibitory concentrations of both the total extract and the isolated compound were low. The minimum inhibitory concentration of the compound isolated from P. setifera was 0.49 μg/mL against C. kefyr , 0.98 μg/mL against C. albicans and C. norvegensis and 1.95 μg/mL against C. krusei. The oral dosing of the extract and the isolated compound did not show any significant effect on the activity of alanine aminotransferase, aspirate aminotransferase and the levels of blood urea and serum creatinine. Copyright © 2017 John Wiley & Sons, Ltd.     

Norlignans, acylphloroglucinols, and a dimeric xanthone from Hypericum chinense

Two new norlignans, hyperiones A (1) and B (2), three new acylphloroglucinols, aspidinol C (3) and hyperaspidinols A (5) and B (6), the known compound aspidinol D (4), and the symmetrical dimeric xanthone hyperidixanthone (7) were isolated from Hypericum chinense. Their structures were established by spectroscopic analysis. In an antibacterial assay using a panel of multidrug-resistant (MDR) strains, compounds 3 and 4 exhibited promising activity against the NorA efflux protein overexpressing MDR Staphylococcus aureus strain SA-1199B with a minimum inhibitory concentration (MIC) of 2 μg/mL (8.4 μM) and 4 μg/mL (16.8 μM), respectively. The positive control antibiotic norfloxacin showed activity at MIC 32 μg/mL (100 μM).     

Antimalarial activity of extract and norbergenin derivatives from the stem bark of Diospyros sanza-minika A. Chevalier (Ebenaceae)

The methanol extract from the stem bark of Diospyros sanza-minika as well as five norbergenin derivatives isolated from this crude extract were evaluated for their in vitro activity against Plasmodium falciparum K1 and cytotoxicity on MRC-5 cells. 4-O-(3'-methylgalloyl)norbergenin was found to be the most potent compound (IC(50) 0.6 μg/mL; CC(50) 24.7 μg/mL), followed by 4-O-galloylnorbergenin (IC(50) 3.9 μg/mL; CC(50) > 64 μg/mL) and 11-O-p-hydroxy-benzoyl-norbergenin (IC(50) 4.9 μg/mL; CC(50) > 64 μg/mL). Norbergenin and 4-O-syringoylnorbergenin were inactive (IC(50) > 32 μg/mL; CC(50) > 64 μg/mL). The antimalarial activity of the pure constituents and of the methanol extract from the stem bark of Diospyros sanza-minika is reported for the first time. The results provide interesting baseline information for the potential use of the crude extract well as some of the isolated compounds in the search for novel antimalarial compounds.