Screening of Marine Algal Extracts for Anti-settlement Activities against Microalgae and Macroalgae

The ban on the use of TBT-based antifouling paints for boats under 25 m in length has lead to a search for new non-toxic antifoulants. One of the most promising alternative technologies to heavy metal based antifouling paint is the development of antifouling coatings whose active ingredients are naturally occurring compounds from marine organisms. This is based on the principle that marine organisms also face the problem of the presence of epibionts on their own surfaces. In this study, the antifouling activity of a series of aqueous, ethanolic and dichloromethane extracts from thirty algae from the North East Atlantic coast was investigated. The extracts were tested in laboratory assays against species representative of two major groups of fouling organisms, viz . macroalgae and microalgae. The activity of several extracts was comparable to that of heavy metals and biocides (such as TBTO and CuSO 4 ) currently used in antifouling paints and their lack of toxicity with respect to the larvae of oysters and sea urchins suggests a potential for novel active ingredients.     

Antifungal Properties of Crude Extracts of Five Egyptian Medicinal Plants Against Dermatophytes and Emerging Fungi

Antifungal properties of the crude extracts of five medicinal plants (Artemisia judaica, Ballota undulate, Cleome amblyocarpa, Peganum harmala, and Teucrium polium) were tested against dermatophytes and emerging fungi. Ethanol extract of Ballota undulate was the most effective against all tested fungi. Paecilomyces lilacinus, P. variotii, and Candida albicans were the most sensitive organisms. The minimum inhibitory concentration (MIC) of Ballota undulate ethanol extract against C. albicans, P. lilacinus, and P. variotii was 25 mg/ml. GC–MS analysis revealed that Ballota undulate ethanol extract contains 35 aliphatic and aromatic hydrocarbons, sesquiterpene hydrocarbon along with some other essential oils, which could be involved in antifungal activity. Light microscopy and scanning electron microscopy (SEM) have proved that Ballota undulate ethanol extract exhibits fungicidal effect on P. lilacinus through alterations in hyphal structures including budding of hyphal tip, anomalous structure, such as swelling, decrease in cytoplasmic content, with clear separation of cytoplasm from cell wall in hyphae. SEM clearly showed distorted mycelium, squashed and flattened conidiophores bearing damaged metullae. Eventually, the mycelia became papillated, flattened, and empty. Puncturing and squashing of hyphae as well as complete cell wall disruption were clear signs of complete death of hyphae.     

New Antifungal Agents and New Formulations Against Dermatophytes

A variety of oral and topical antifungal agents are available for the treatment of superficial fungal infections caused by dermatophytes. This review builds on the antifungal therapy update published in this journal for the first special issue on Dermatophytosis (Gupta and Cooper 2008;166:353–67). Since 2008, there have not been additions to the oral antifungal armamentarium, with terbinafine, itraconazole, and fluconazole still in widespread use, albeit for generally more severe or recalcitrant infections. Griseofulvin is used in the treatment of tinea capitis. Oral ketoconazole has fallen out of favor in many jurisdictions due to risks of hepatotoxicity. Topical antifungals, applied once or twice daily, are the primary treatment for tinea pedis, tinea corporis/tinea cruris, and mild cases of tinea unguium. Newer topical antifungal agents introduced include the azoles, efinaconazole, luliconazole, and sertaconazole, and the oxaborole, tavaborole. Research is focused on developing formulations of existing topical antifungals that utilize novel delivery systems in order to enhance treatment efficacy and compliance.     

Antifungal Activity of Essential Oils Against Candida Species Isolated from Clinical Samples

Mycopathologia - We evaluated the in vitro antifungal activity of essential oils obtained from the aromatic plants Laurus nobilis, Thymus vulgaris, Mentha piperita, Cymbopogon citratus and Lippia...     

Comparison of Antifungal Activities of Gentian Violet and Povidone-Iodine Against Clinical Isolates of Candida Species and Other Yeasts: A Framework to Establish Topical Disinfectant Activities

We evaluated antifungal activity as assessed by the contact time in topical use of gentian violet (GV) and povidone-iodine (PI) against Candida strains. A total of 102 yeast isolates were used in this study. A markedly lower minimal inhibitory concentration (MIC)₉₀ of GV than of PI was detected for all yeast isolates. No remarkable difference in the MICs was observed among the identical strains isolated from different clinical sites for both GV and PI. Although the minimal fungicidal activities (MFCs) of PI were identical for all tested time points, the fungicidal activity of GV decreased during the time course of incubation. These results indicate that, whereas GV is more effective than PI, the topical disinfectant efficacy of GV should be estimated using the MFC_5 min and not the MIC or the MFC_24 h for overall prevention of catheter-related bloodstream infections and oral infections.     

不同念珠藻的提取物对酪氨酸酶活性的抑制作用

研究了Nostoc sp.FACHB87、 Nostoc paludosum FACHB89等10株念珠藻的甲醇提取物对酪氨酸酶的抑制作用.结果表明,随着提取物浓度的升高,对酪氨酸酶的抑制作用也增强.其中Nostoc sp.FACHB892的甲醇提取物对酪氨酸酶抑制作用最强,在33.3 μg/mL的最高测试浓度下,抑制率可达到60.54%;Nostoc sp.FACHB95、 Nostoc sp.FACHB106、 N.punctiforme FACHB252、N.calcicola FACHB389和N.parmiloides FACHB392的甲醇提取物,在33.3 μg/mL的最高测试浓度下, 抑制率分别为41.55%、 37.58%、46.94%、52.12%和47.95%.Nostoc sp.FACHB892的甲醇提取物对酪氨酸酶的抑制作用表现为可逆抑制,抑制类型为非竞争型抑制.     

In Vitro Antifungal Activity of Micafungin and Caspofungin Against Dermatophytes Isolated from China

Aims

The aims of this study are to investigate the in vitro activities of micafungin and caspofungin that are two new echinocandin antifungal drugs against clinically isolated dermatophytes in China and to define MEC (minimal effective concentration) as the reading endpoints of this study in accordance with (Clinical and laboratory Standards Institute) CLSI M38-A2 reference.

Methods

Minimal effective concentrations (MECs) of micafungin and caspofungin for 82 dermatophyte strains were determined according to CLSI (formerly NCCLS) M38-A2 broth microdilution methods.

Results

(1) The MEC_90s of micafungin for Trichophyton violaceum and Trichophyton tonsurans were 0.25 μg/mL, and for Microsporum canis and Trichophyton verrucosum were 0.06 μg/mL. The MEC_90s for Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum gypseum and Epidermophyton floccosum were 0.03 μg/mL. (2) The MEC_90s of caspofungin for T. rubrum, T. violaceum and T. tonsurans were 1 μg/mL, and for T. mentagrophytes, M. canis, M. gypseum, E. floccosum and T. verrucosum were 0.5 μg/mL. (3) Compared with caspofungin, micafungin demonstrated lower MEC value to dermatophytes (P < 0.05).

Conclusions

Micafungin has stronger in vitro antifungal activity than caspofungin.     

山苍子油对白假丝酵母抗菌活性研究

研究山苍子油对白假丝酵母菌的抗菌活性,并阐明其可能的抗菌机制。通过水蒸馏法提取山苍子油,并利用气相色谱-质谱联用仪(GC/MS)分析其成分。通过琼脂平板稀释法测定山苍子油对白假丝酵母的最低抑菌浓度(MIC)和最低杀菌浓度(MFC),并研究山苍子油对白假丝酵母的抗菌动力学;同时利用扫描电子显微镜(SEM)和透射电子显微镜(TEM)观察山苍子油对白假丝酵母细胞超微结构的影响。结果表明,自提山苍子油主成分为柠檬烯(26.51%),柠檬醛(11.94%)和马鞭烯醇(11.84%)。山苍子油对白假丝酵母菌的MIC和MFC均为1.25μL/m L;其抗菌动力学研究表明浓度低于其MIC时,山苍子油仅延长白假丝酵母的生长适应期,并不能彻底杀死细胞;SEM结果表示,山苍子易破坏正在出芽的细胞;TEM显示出山苍子破坏细胞壁,细胞膜,使细胞裂解。山苍子油具有优良的抗白假丝酵母活性,且白假丝酵母在芽痕处对山苍子油比较敏感,高浓度的精油(5.0μL/m L)对细胞产生不可逆破坏;山苍子油杀菌的靶标可能是细胞壁和细胞外膜,使细胞内大分子外泄,细胞器变形,最终导致细胞死亡。     

Antifungal Activity of Schinifoline Against Candida Albicans in Caenorhabditis Elegans

Zanthoxylum schinifolium has been used as spices and traditional medicine in China for hundreds of years. A variety of active substances have been isolated from Zanthoxylum schinifolium using biological and chemical techniques. Among these substances, the effect of schinifoline has gradually attracted much attention. Candida albicans is one of the most common pathogens isolated from the gastrointestinal tract, vagina, and mouth in healthy individuals. In a healthy population, there are various mechanisms in host, such as the microbial flora, the epithelial barriers, and the innate immune system, that can control the presence of Candida albicans. However, when host immunity is compromised, an invasive fungal infection is more likely to occur. In this study, we explored the antifungal activity of schinifoline against Candida albicans in Caenorhabditis elegans. To determine the optimal concentration of schinifoline, we investigated the lifespan, defecation cycle and locomotion behavior of Caenorhabditis elegans after treatment with schinifoline. In addition, we examined colony formation in the intestine of Caenorhabditis elegans after Candida albicans infection. The results indicated that 100 and 200 mg/L of schinifoline could prolonged the lifespan, shorten the defecation cycle and increased the locomotion behavior of Caenorhabditis elegans, with 100 mg/L of schinifoline being the optimal concentration. Moreover, 100 mg/L of schinifoline increased the lifespan of Caenorhabditis elegans after infection and inhibited the colony formation of Candida albicans in Caenorhabditis elegans intestine. Therefore, we concluded that schinifoline exhibits anti-fungal effects and its potential use as natural drugs should be further explored in future studies.     

Antifungal Activity of Baicalein Against Candida krusei Does Not Involve Apoptosis

The present study was designed to evaluate the antifungal activity of baicalein against Candida krusei isolates. Using a broth microdilution assay, baicalein exhibited potent in vitro antifungal activity against C. krusei isolates with a minimum inhibitory concentration of 2.7 μg/ml. Flow cytometric study indicated that baicalein depolarized mitochondrial membrane potential in a concentration-dependent manner. However, mechanistic analyses showed that the intracellular reactive oxygen species (ROS) level was virtually unchanged, and massive DNA fragmentation was not observed in C. krusei isolates after baicalein treatment even at a concentration which was apoptotic in C. albicans. Taken together, we conclude that the antifungal activity of baicalein in C. krusei isolates occurs through perturbation in mitochondrial homeostasis without causing elevation of the intracellular ROS level and does not involve apoptosis.     

Antifungal Activity of Synthetic Scorpion Venom-Derived Peptide Analogues Against Candida albicans

International Journal of Peptide Research and Therapeutics - Fungal infections are becoming a serious problem due to their high morbidity and mortality combined with the rise in drug resistance and...     

九种蕨类植物多糖提取物抗动植物病原菌活性

从9种蕨类植物中提取多糖,以苯酚-硫酸比色法测定其含量,并采用纸片法进行抗动植物病原菌实验。结果表明,9种蕨类多糖含量差别较大,其多糖提取物表现出不同程度的抑制动植物病原菌活性。     

Volatile Chemical Composition,Antibacterial and Antifungal Activities of Extracts from Different Parts of Globba schomburgkii Hook.f.

Globba schomburgkii Hook.f. is an ornamental plant that has recently found increasing demand as cut flowers, hence generating a significant number of by‐products from different parts of the plant. To investigate the further applications of these by‐products, twelve crude extracts from rhizomes, stalks, leaves, and flowers were prepared by serial exhaustive extraction. The volatile composition of these extracts was analyzed by GC/MS; a total of 89 compounds were identified, most of which were sesquiterpenes as well as some labdane‐type diterpenes. The antimicrobial activities of these extracts were evaluated, revealing a correlation between the terpenoid content and antibacterial activities. Notably, the dichloromethane extracts of rhizomes and flowers, which contained the highest amount of terpenoids (e. g., α‐gurjunene, guaia‐9,11‐diene, γ‐bicyclohomofarnesal, β‐caryophyllene, and caryophyllene oxide), displayed the most prominent antibacterial activities. This work demonstrates the potential use of the crude extracts from G. schomburgkii as natural antibacterial ingredients for pharmaceutical and other applications.     

Virulence Factors and Antifungal Susceptibility in Candida Species Isolated from Dermatomycosis Patients

Mycopathologia - Dermatomycoses caused by Candida spp. are increasingly common, however there are few reports in the literature regarding their epidemiology, pathogenesis and antifungal...     

菊芋叶片提取物抑菌活性与化学成分的研究

为了开发新型植物源杀菌剂和充分利用菊芋(Helianthus tuberosus L.)资源,本文尝试用石油醚、乙醚、乙酸乙酯和水等4种溶剂对菊芋叶片进行平行提取,采用生长速率法测定菊芋叶片提取物对水稻纹枯菌(Rhizoc-tonia solaniKühn)、小麦赤霉菌[Gibberella zeae(Schw.)Petch]、番茄早疫菌[Alternaria solani(Ellis et Martin)Jones et Grour]和番茄灰霉菌(Botrytis cinerea Pers.)生长量的抑制活性;并通过试管法和滤纸法对菊芋叶片内化学成分进行初步预试。抑菌实验结果表明:(1)菊芋叶片各溶剂提取物处理与对照处理相比差异显著;(2)菊芋叶片水提取物处理与各有机溶剂提取物处理差异也基本显著;(3)菊芋叶片各溶剂提取物同浓度处理对水稻纹枯菌、番茄早疫菌和番茄灰霉菌抑制效果较好;(4)菊芋叶片乙酸乙酯提取物抑菌效果最为显著,浓度为20mg/mL时对番茄早疫菌和番茄灰霉菌已达到完全抑制,对水稻纹枯菌抑制率也达到77.91%。初步化学预试结果说明,菊芋叶片中含有蛋白质、氨基酸、还原糖类、有机酸、酚类和鞣质、黄酮类、内酯类、强心甙以及油脂等化学成分。     

In Vitro Activities of New Triazole Antifungal Agents, Posaconazole and Voriconazole, Against Oral Candida Isolates from Patients Suffering from Denture Stomatitis

Denture stomatitis is often treated with antifungal agents but recurrences or new episodes are common, and certain episodes can be resistant. New triazoles, such as posaconazole and voriconazole, may represent useful alternatives for management. In vitro activities of amphotericin B, nystatin, miconazole, fluconazole, itraconazole, posaconazole and voriconazole against 150 oral Candida (101 C. albicans, 18 C. tropicalis, 12 C. glabrata, 11 C. guilliermondii, 4 C. parapsilosis, 2 Saccharomyces cerevisiae, 1 C. dubliniensis and 1 C. krusei) from 100 denture wearers were tested by the CLSI M27-A3 method. Resistant isolates were retested by Sensititre YeastOne and Etest. Most antifungal agents were very active. However, 4 C. glabrata (33.3%), 2 C. tropicalis (11.1%), 6 C. albicans (5.6%) and 1 C. krusei were resistant to itraconazole. Posaconazole was active against 143 yeast isolates (95.3%): 6 C. albicans (5.9%) and 1 C. tropicalis (5.6%) were resistant. Geometric mean MICs were 0.036 μg/ml for C. parapsilosis, 0.062 μg/ml for C. albicans, 0.085 μg/ml for C. tropicalis, 0.387 μg/ml for C. guilliermondii and 0.498 μg/ml for C. glabrata. Voriconazole was active against 148 isolates (98.7%) with geometric mean MICs ranging from 0.030 μg/ml for C. parapsilosis, 0.042 μg/ml for C. albicans, 0.048 μg/ml for C. tropicalis, 0.082 μg/ml for C. guilliermondii, to 0.137 μg/ml for C. glabrata. Only 2 C. albicans (2%) were resistant to voriconazole showing cross-resistance to other azoles. Posaconazole and voriconazole have excellent in vitro activities against all Candida isolates and could represent useful alternatives for recalcitrant or recurrent candidiasis.     

Antifungal Activity of Geldanamycin Alone or in Combination with Fluconazole Against Candida species

A standardized broth microdilution method was used to test the antifungal activity of geldanamycin (GA), an inhibitor of heat shock protein 90 (Hsp90), alone or in combination with the antifungal agent fluconazole (FLC) against 32 clinical isolates of Candida spp. In addition, a disk diffusion test was also used to evaluate the antifungal effect of these two drugs against Candida spp. by measuring the inhibition zone diameters. We found that the range of minimal inhibitory concentrations (MICs) for GA alone against Candida spp. was 3.2–12.8 mg/L and the geometric mean of MICs was 6.54 mg/L. In addition, the combination of GA with FLC showed synergistic effects in vitro against 2 FLC-susceptible and 6 FLC-resistant isolates of C. albicans. As for the other isolates, indifference but no antagonism was observed. In the disk diffusion assay, the diameter of inhibition zones for FLC combined with GA against FLC-resistant C. albicans isolates was 30 mm, while no inhibition was observed with FLC alone. These results demonstrate that GA possesses antifungal activity against Candida spp., and the combination of GA with FLC shows in vitro synergistic activity against some C. albicans isolates, especially those resistant to FLC.     

炭团菌提取物对樟子松枯梢病菌的抑菌活性及稳定性

摘要 【目的】获得炭团菌液体培养菌液中高效抑制樟子松枯梢病菌的活性物质。【方法】炭团菌液体培养菌液中活性物质的提取采用水提和酯提2种方式。水提方式采用直接提取法和超声波提取法2种方法,酯提方式选择正丁醇、乙酸乙酯、乙醇3种萃取剂。各提取物对病原菌的抑菌活性研究选用菌丝生长抑制率和孢子萌发抑制率2个指标,对病原菌菌丝生长的抑制测定采用生长速率法,对病原菌孢子萌发的抑制试验采用悬滴法。炭团菌液体培养菌液乙酸乙酯提取物稳定性的研究选用紫外线、温度、pH值、氧化剂与还原剂以及贮存时间5个因子。乙酸乙酯提取物中抑菌活性成分的分离采用柱层析、纯化采用薄层层析、结构鉴定采用紫外光谱（UV）、红外光谱（IR）、气质联用（GC-MS）和核磁共振（NMR）等分析测试技术。【结果】炭团菌液体培养菌液5种提取物对樟子松枯梢病菌均有一定的抑菌活性,其中乙酸乙酯提取物对病原菌菌丝生长的抑制率最高,达到73.20%;乙酸乙酯提取物、超声波提取物、正丁醇提取物对病原菌孢子萌发抑制率均超过90%。乙酸乙酯提取物对自然环境下的紫外线、温度具有很高的稳定性,并且具有一定的抗氧化还原能力和良好的耐热性,长期贮存不影响其抑菌活性。乙酸乙酯提取物中有3个组分,组分I的抑菌率最高（72.94%）。组分I含3种化合物,其中得率最高（57.952%）的为对甲氧基肉桂酸甲酯,化学式为C11H12O3。其他两种化合物为邻苯二甲酸二丁酯和邻苯二甲酸二异丁酯。本研究首次发现上述3种化合物的天然存在。【结论】炭团菌液体培养菌液乙酸乙酯提取物对樟子松枯梢病菌具有较高的抑菌活性,在自然环境下具有很高的稳定性,具有很高的开发价值和应用前景,其主要抑菌活性成分为对甲氧基肉桂酸甲酯。对甲氧基肉桂酸甲酯作为医药中间体主要用于化妆品中,作紫外防护吸收剂;邻苯二甲酸二丁酯和邻苯二甲酸二异丁酯均是聚氯乙烯最常用的增塑剂。上述3种化合物天然存在的发现,对于医药工业和化学工业具有极为重要的意义。     

大型海藻的组织培养及其应用

文章对大型海藻组织培养中愈伤组织和原生质体的获得、除菌效果以及植物生长调节物质的选用的研究进展进行了概述,并对其应用和研究前景作了分析和展望。