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Objectives The aim was to determine the chemical composition of the essential oil of Kadsura longipedunculata and the biological activity of the oil and its major components. Methods The essential oil from stem bark of Kadsura longipedunculata was analysed by capillary gas chromatography (GLC/FID) and gas chromatography–mass spectrometry (GLC/MS). The ability of the oil to reduce diphenylpicrylhydrazine (DPPH•) was used to evaluate the antioxidant activity. Inhibition of both lipoxygenase and prostaglandin E2 was used to assess the anti-inflammatory activity. Antimicrobial activity was studied in vitro against a range of bacteria and fungi using diffusion and microdilution methods. Inhibition of trypanosome proliferation was assessed using resazurin as vital stain. The in-vitro cytotoxicity of the essential oil on six human cancer cell lines (HepG2, MIA PaCa-2, HeLa, HL-60, MDA-MB-231 and SW-480) was examined using the MTT assay. Key findings Fifty compounds, representing 97.63% of total oil, were identified. δ-Cadinene (21.79%), camphene (7.27%), borneol (6.05%), cubenol (5.12%) and δ-cadinol (5.11%) were found to be the major components of the oil. The oil exerted a good antimicrobial activity against all Gram-positive bacteria tested, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecalis. Streptococcus pyogenes and S. agalactiae were the most sensitive bacteria with a minimal inhibitory concentration (MIC) of 60 µg/ml oil. The essential oil showed a moderate fungicidal activity against yeasts, but it did not show any activity against Gram-negative bacteria. The essential oil showed a good trypanocidal activity in Trypanosoma b. brucei with an IC50 value of 50.52 ± 0.029 µg/ml. Radical scavenging activity had an IC50 value of 3.06 ± 0.79 mg/ml. 5-Lipoxygenase inhibition (IC50 = 38.58 µg/ml) and prostaglandin E2 production inhibition (28.82% at 25 µg/ml) accounted for anti-inflammatory activity of the oil. The oil exhibited some degree of cytotoxic activity against MIA PaCa-2, HepG-2 and SW-480 cell lines with IC50 values of 133.53, 136.96 and 136.62 µg/ml, respectively. The oil increased caspase 3/7 activity (an indicator of apoptosis) 2.5–4 fold in MIA Paca-2 cells. Camphene and borneol did not show antioxidant activity. However, both compounds exhibited some degree of antimicrobial, trypanocidal, anti-inflammatory and cytotoxic activity. Conclusions This investigation provided evidence for, and confirmed the efficacy of, K. longipedunculata, a traditionally used Chinese medicinal plant for the treatment of inflammation and infection.

Rose oil is the essential oil extracted from the petals of the damask rose. It is an ingredient of cosmetic as well as health care products and it is used in folk medicine and in aromatherapy. It is well known that essential oils are able to permeate the skin whereas the lipophilic properties of the compounds as well as the application site have an influence on their permeation behaviour. In this paper, we investigated the influence of the application site on the permeation of rose oil.We tested the permeation of rose oil and its major ingredients through human heat-separated epidermis of abdominal skin, breast skin, and skin from the upper arm.We found that no application site is suited best for all substances tested to permeate the skin. It depends on the structure of the essential oil ingredients which application site should be chosen for topical application, which is already known for pharmaceuticals. Furthermore, when investigating the permeation of essential oils, we found that not only the P(app) value but also the lag-time should be considered.The application site of substances to permeate the skin has a great influence on the permeation behaviour. As essential oils are volatile mixtures and their retention on the surface of the skin amounts only to a few hours, the lag-time should be considered in addition to the P(app)-value.

Introduction: Aqueous and ethanolic extracts of Cajanus cajan (Fabaceae) were examined in vitro for their antiviral activity against herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2). Materials and Methods: The antiviral activity was determined using a plaque reduction assay. The cytotoxic concentration (CC50) as well as the inhibitory concentration (IC50) of the extracts was determined from dose-response curves. Results: All extracts tested revealed a high antiviral activity against cell-free HSV-1 and HSV-2. The most active one was the Cajanus ethanol extract with IC50 values of 0.022 µg/ml for HSV-1 and 0.1 µg/ml for HSV-2. In order to identify the mode of antiviral action, the extracts were added to the host cells or viruses at different stages of infection. HSV-1 and HSV-2 were considerably inactivated when the viruses were pretreated with the extracts for 1 h prior to cell infection. At maximum non-cytotoxic concentrations of the extracts, plaque formation was significantly reduced by 95–99% for HSV-1 and HSV-2. In a time-dependent assay with cell-free HSV-1 over a period of 2 h, a clearly time-dependent effect was demonstrated whereby the Cajanus ethanol extract revealed a much higher activity than the Cajanus aqueous one. Conclusion: The results obtained indicate that the extracts affect HSV before cell adsorption, but have no effect on the intracellular virus replication. According to our findings, a thera-peutic application of Cajanus ethanolic extracts containing crEme or ointment as antiviral agent in recurrent HSV in-fection appears to be promising.

Plants of the genus Coreopsis contain rare phenylpropanoids of the 1′-hydroxyeugenol (Eu) type. To investigate the biological activities of these compounds, 1′-hydroxyeugenol isobutyrate (Eu1) and its derivatives were synthesized. The aim was to separate racemic Eul by high-performance liquid chromatography into its enantiomers on a preparative scale, in order subsequently to synthesize the equivalent esters. To control the stereoselectivity of esterification of Eul, analytical systems investigated for Eu1Eu5 can be utilized. The best results were obtained on microcrystalline cellulose triacetate (CTA), Pirkle Convent phenylglycine and Chiracel OK columns. Racemic Eu1 could be separated on a preparative scale on CTA.

Pseudoisoeugenols are phenylpropanoids with a rare 2,5-dioxy-substitution pattern at the phenyl ring. Their biosynthetic pathway up to anethole appears to be identical to that of ordinary phenylpropanoids. The biosynthetic step leading from anethole (1-propenyl-4-methoxy benzene) to pseudoisoeugenol (1-propenyl-2-hydroxy5-methoxy benzene) was examined using a tissue culture of Pimpinella anisum and presentation of 13C labelled precursors. It involves migration of the side chain during the introduction of the OH-2-group.

The effect of different essential oils as well as of isolated mono- and sesquiterpenes on the viability of bloodstream forms of Trypanosoma brucei, promastigotes of Leishmania major and human HL-60 cells was evaluated using the Almar Blue assay. Of the 12 essential oils and 8 terpenes investigated, only three essential oils, Melissa officinalis (balmmint) oil, Thymus vulgaris (thyme) oil, and Melaleuca alternifolia (tea tree) oil were about 50-fold and 80-fold more toxic to bloodstream forms of T. brucei than to HL-60 cells, respectively. Terpinen-4-ol, the main compound of the Australian tea tree oil, was even 1000-fold more toxic to trypanosomes than to the human cells. On the other hand, none of the essential oils and terpenes tested were more toxic to promastigotes of L. major than to HL-60 cells.

Hydroalcoholic extracts and pressed juice from Echinacea pallida were phytochemically characterised by HPLC-MS analyses. Ferulic and caffeic acid derivatives were identified as major constituents. All tested extracts and pressed juice from Echinacea pallida exhibited a low cytotoxic activity on monkey kidney cells in vitro. The inhibitory activity of Echinacea against herpes simplex virus types 1 and 2 (HSV-1, HSV-2) was analysed with plaque reduction assays. All hydroalcoholic extracts exhibited high levels of antiviral activity against both types of herpesvirus in a dose-dependent manner. Plaque formation was significantly reduced by more than 99 % or completely absent. Pressed juice from E. pallida revealed the highest antiviral activity against HSV-1 and HSV-2 when compared to hydroalcoholic Echinacea extracts and even highly diluted Echinacea pressed juice still inhibited viral infectivity. Hydroalcoholic extracts were quite active against herpetic infection when HSV-1 or HSV-2 were pretreated with the extracts. In contrast, Echinacea pressed juice revealed antiviral activity during all phases of the viral replication cycle. Additionally, Echinacea pressed juice demonstrated protection of cells against viral infection. In conclusion, hydroalcoholic E. pallida extracts interfere with free herpesvirus but pressed juice is able to interact with herpesvirus inside and outside the cell as well as to protect cells against viral infection, probably by interfering with virus attachment. Hydroalcoholic extracts and pressed juice from E. pallida demonstrated high selectivity indices, a necessary prerequisite for a potential topical treatment of herpetic infections. Different types of Echinacea preparations, such as commercial tinctures, tablets, and teas, are expected to offer different antiviral profiles.

Essential oils are complex natural mixtures, their main constituents, e.g. terpenes and phenylpropanoids, being responsible for their biological properties. Essential oils from eucalyptus, tea tree and thyme and their major monoterpene compounds α‐terpinene, γ‐terpinene, α‐pinene, p‐cymene, terpinen‐4‐ol, α‐terpineol, thymol, citral and 1,8‐cineole were examined for their antiviral activity against herpes simplex virus type 1 (HSV‐1) in vitro. These essential oils were able to reduce viral infectivity by >96%, the monoterpenes inhibited HSV by about >80%. The mode of antiviral action has been determined, only moderate antiviral effects were revealed by essential oils and monoterpenes when these drugs were added to host cells prior to infection or after entry of HSV into cells. However, both essential oils and monoterpenes exhibited high anti‐HSV‐1 activity by direct inactivation of free virus particles. All tested drugs interacted in a dose‐dependent manner with herpesvirus particles thereby inactivating viral infection. Among the analysed compounds, monoterpene hydrocarbons were slightly superior to monoterpene alcohols in their antiviral activity, α‐pinene and α‐terpineol revealed the highest selectivity index. However, mixtures of different monoterpenes present in natural tea tree essential oil revealed a ten‐fold higher selectivity index and a lower toxicity than its isolated single monoterpenes. Copyright © 2009 John Wiley & Sons, Ltd.

Despite the clinical proven efficacy of fragrant sumac extracts for the treatment of urological diseases like overactive bladder and bacterial infection associated symptoms, little is found in literature about the mode of antiviral action and safety of this active pharmaceutical ingredient. For cytotoxicity assay and mechanistic investigation we used RC-37 cells (African green monkey kidney cells). The fragrant sumac extract demonstrated a very low cytotoxic activity in vitro with a CC50 (50% cytotoxic concentration) value of 2.7%. Using a plaque reduction assay, the extract showed a high level of anti-HSV-1 activity with an IC50 (50% inhibitory concentration) value of 0.0005%. In addition, at maximum noncytotoxic concentration (0.25%) plaque formation was significantly reduced by more than 99.9% when HSV-1 was pretreated with the fragrant sumac extract for 1h prior to cell infection. Surprisingly, when host cells were treated with the extract for 1h prior to virus infection, the infectivity of HSV-1 was reduced by 50%. These results suggest that the fragrant sumac extract reveals a dual mode of antiviral action. Some compounds of the fragrant sumac extract may interact not only with the viruses but also with the surface of host cells impairing the ability to adsorb to and penetrate into the host cells. These findings are consistent with the very few reports of minor undesirable side effects from clinical studies with fragrant sumac extract and support also its use for microbiological associated diseases of urinary tract.

For essential oils, several biological effects such as antibacterial, anti-inflammatory, expectorant, and blood-circulation-enhancing properties have been described. The method of application depends on the pathophysiology, the desired outcome, safety, and toxicity data. For treating respiratory symptoms and nervous disorders, inhalation may be the best means of application, whereas topical application is the best way for treating skin diseases. For dermal application, percutaneous absorption of essential oil and oil components is of great interest. Essential oils are complex mixtures of different volatile substances. So, the question is raised whether all components of a complex composed essential oil are equivalent with respect to their human skin permeation. By means of artificial mixtures of different essential oil ingredients, we investigated the cooperative effect of monoterpenes and phenylpropanoids on the permeation through heat-separated human skin epidermis in static Franz-Diffusion Cells. Limonene showed an enhancing effect on the permeation of citronellol and eugenol. Both alpha-pinene and myrcene increased the apparent permeability ( P(app)) value of phenylethanol. beta-Pinene had an enhancing effect on the permeation behaviour of methyleugenol but not of geraniol. The investigations clearly show that cooperative effects of single essential oil components may influence percutaneous essential oil absorption.

The abundant use of anti-infective agents resulted in the emergence of drug-resistant bacteria, fungi, and viruses. To overcome the increasing resistance of pathogenic microbes, a variety of medicinal plants have been screened worldwide for their antimicrobial properties. The aim is to find new, effective antimicrobial agents with novel modes of actions. Essential oils derived from aromatic medicinal plants have been reported to exhibit exceptionally good antimicrobial effects against bacteria, yeasts, filamentous fungi, and viruses. The progress of this expanding scientific field will be documented by the most important results published in the last decade.

Genital herpes caused by herpes simplex virus type 2 (HSV-2) is a chronic, persistent infection spreading efficiently and silently as sexually transmitted disease through the population. Antiviral agents currently applied for the treatment of herpesvirus infections include acyclovir and derivatives. Aqueous and ethanolic extracts of propolis were phytochemically analysed, different polyphenols, flavonoids and phenylcarboxylic acids were identified as major constituents. The aqueous propolis extract revealed a relatively high amount of phenylcarboxylic acids and low concentrations flavonoids when compared to the ethanolic special extract GH 2002. The cytotoxic and antiherpetic effect of propolis extracts against HSV-2 was analysed in cell culture, and revealed a moderate cytotoxicity on RC-37 cells. The 50% inhibitory concentration (IC(50)) of aqueous and ethanolic GH 2002 propolis extracts for HSV-2 plaque formation was determined at 0.0005% and 0.0004%, respectively. Both propolis extracts exhibited high levels of antiviral activity against HSV-2 in viral suspension tests, infectivity was significantly reduced by >99% and a direct concentration- and time-dependent antiherpetic activity could be demonstrated for both extracts. In order to determine the mode of virus suppression by propolis, the extracts were added at different times during the viral infection cycle. Addition of these drugs to uninfected cells prior to infection or to herpesvirus-infected cells during intracellular replication had no effect on virus multiplication. However both propolis extracts exhibited high anti-herpetic activity when viruses were pretreated with these drugs prior to infection. Selectivity indices were determined at 80 and 42.5 for the aqueous and ethanolic extract, respectively, thus propolis extracts might be suitable for topical therapy in recurrent herpetic infection.

Pancreatic cancer is one of the most aggressive human malignancies, with an extremely poor prognosis. The paucity of curative therapies has translated into an overall 5-year survival rate of less than 5%, underscoring a desperate need for new therapeutic options. Artesunate (ART), clinically used as anti-malarial agent, has recently revealed remarkable anti-tumor activity. However, the mechanisms underlying those activities in pancreatic cancer are not yet known. Here we evaluated the anti-tumor activity of Artesunate and the possible underlying mechanisms in pancreatic cancer. MiaPaCa-2 (poorly differentiated) and BxPC-3 (moderately differentiated) pancreatic cancer cell lines were treated with Artesunate and the effect was monitored by a tetrazolium-based assay (MTS) for evaluating cell viability and by flow cytometry and caspase 3/7 activation for apoptosis evaluation. In addition cDNA arrays were used to identify differentially expressed genes. The microarray data were then validated by RT-PCR and Western blotting. Moreover, pathways associated with these expression changes were identified using the Ingenuity Pathway Analysis. The expression analysis identified a common set of genes that were regulated by Artesunate in pancreatic cancer. Our results provide the first in vitro evidence for the therapeutic utility of Artesunate in pancreatic cancer. Moreover, we identified Artesunate as a novel topoisomerase IIalpha inhibitor that inhibits pancreatic cancer growth through modulation of multiple signaling pathways. The present analysis is a starting point for the generation of hypotheses on candidate genes and for a more detailed dissection of the functional role of individual genes for the activity of Artesunate in tumor cells.

Phellodendron amurense Rupr. bark extracts were examined for antioxidant activity, antimicrobial activity and antiviral activity on herpes simplex virus type 1 (HSV-1). Ethanol extract showed higher content of both total phenolic and flavonoid than aqueous extract. In DPPH (2, 2-diphenyl-1-picrylhydrazyl) assay, the concentration providing 50% inhibition (IC50) values were 6.73 ± 0.87 mg/ml and 4.26 ± 0.59 mg/ml for aqueous and ethanol extracts respectively. Ethanol extract had a much higher antimicrobial activity than aqueous extract. Furthermore, the antiviral activity of the ethanol extract on HSV-1 was also tested. The maximum noncytotoxic concentration was 44.12 μg/ml for RC-37 cells. Plaque formation was inhibited by 74±6% when HSV-1 was pretreated with the extract prior to adsorption, whereas pretreatment of the cells with the extract, added during adsorption or after the adsorption only exhibited above 10% antiviral effect. This study has to some extent validated the medicinal potential of P. amurense bark.

Extracts of medicinal plants are increasingly of interest as novel drugs for antimicrobial and antiviral agents, since microorganisms might develop resistance to commonly used antimicrobial or antiviral agents.Ethanolic extracts from Lamiaceae plants prunella, peppermint, rosemary and thyme were phytochemically characterised. The inhibitory activity of four 20% ethanolic plant extracts and four 80% ethanolic extracts against herpes simplex virus (HSV) strains was tested in cell culture.Rosmarinic acid, a typical compound in Lamiaceae species, was identified in the extracts except for thyme 20% ethanolic extract. In addition, some other phenolic compounds such as apigenin- and luteolin-derivatives were identified in different amounts. All extracts exhibited high and concentration-dependent levels of antiviral activity against free acyclovir-sensitive and acyclovir-resistant HSV-1 strains with 50% inhibitory concentrations of 0.05-0.82 microg/ml. Mechanistically, exposure of free virions as well as host cells to prunella and peppermint 80% ethanolic extracts at maximum non-cytotoxic concentrations prior to infection reduced plaque formation drastically. Thus, both extracts revealed a dual mode of action similar to aqueous lemon balm extracts.Since infectivity of acyclovir-susceptible and acyclovir-resistant HSV strains was significantly reduced with Lamiaceae extracts, the results obtained indicate that ethanolic plant extracts affected herpesvirus prior to and during adsorption and in a different way than acyclovir. Based on its dual mode of action, e.g. antiviral effect against free virions and blocking virus attachment to host cells, prunella and peppermint 80% ethanolic extracts are promising antiviral agents in recurrent herpes labialis for topical therapeutic applications.

Background Aqueous extracts from leaves of well known species of the Lamiaceae family were examined for their potency to inhibit infection by human immunodeficiency virus type 1 (HIV-1). Results Extracts from lemon balm (Melissa officinalis L.), peppermint (Mentha × piperita L.), and sage (Salvia officinalis L.) exhibited a high and concentration-dependent activity against the infection of HIV-1 in T-cell lines, primary macrophages, and in ex vivo tonsil histocultures with 50% inhibitory concentrations as low as 0.004%. The aqueous Lamiaceae extracts did not or only at very high concentrations interfere with cell viability. Mechanistically, extract exposure of free virions potently and rapidly inhibited infection, while exposure of surface-bound virions or target cells alone had virtually no antiviral effect. In line with this observation, a virion-fusion assay demonstrated that HIV-1 entry was drastically impaired following treatment of particles with Lamiaceae extracts, and the magnitude of this effect at the early stage of infection correlated with the inhibitory potency on HIV-1 replication. Extracts were active against virions carrying diverse envelopes (X4 and R5 HIV-1, vesicular stomatitis virus, ecotropic murine leukemia virus), but not against a non-enveloped adenovirus. Following exposure to Lamiaceae extracts, the stability of virions as well as virion-associated levels of envelope glycoprotein and processed Gag protein were unaffected, while, surprisingly, sucrose-density equilibrium gradient analyses disclosed a marked increase of virion density. Conclusion Aqueous extracts from Lamiaceae can drastically and rapidly reduce the infectivity of HIV-1 virions at non-cytotoxic concentrations. An extract-induced enhancement of the virion's density prior to its surface engagement appears to be the most likely mode of action. By harbouring also a strong activity against herpes simplex virus type 2, these extracts may provide a basis for the development of novel virucidal topical microbicides.

Extracts and essential oils of medicinal plants are increasingly of interest as novel drugs of antimicrobial and antiviral agents, since herpes simplex virus (HSV) might develop resistance to commonly used antiviral agents. Melissa officinalis essential oil was phytochemically examined by GC-MS analysis, its main constituents were identified as monoterpenaldehydes citral a, citral b and citronellal. The antiviral effect of lemon balm oil, the essential oil of Melissa officinalis, on herpes simplex virus was examined. The inhibitory activity against herpes simplex virus type 1 (HSV-1)and herpes simplex virus type 2 (HSV-2) was tested in vitro on monkey kidney cells using a plaque reduction assay. The 50% inhibitory concentration (IC50) of balm oil for herpes simplex virus plaque formation was determined at high dilutions of 0.0004% and 0.00008% for HSV-1 and HSV-2, respectively. At noncytotoxic concentrations of the oil,plaque formation was significantly reduced by 98.8% for HSV-1 and 97.2% for HSV-2, higher concentrations of lemon balm oil abolished viral infectivity nearly completely. In order to determine the mode of antiviral action of this essential oil, time-on-addition assays were performed. Both herpesviruses were significantly inhibited by pretreatment with balm oil prior to infection of cells. These results indicate that Melissa oil affected the virus before adsorption, but not after penetration into the host cell, thus lemon balm oil is capable of exerting a direct antiviral effect on herpesviruses. Considering the lipophilic nature of lemon balm essential oil, which enables it to penetrate the skin, and a high selectivity index, Melissa officinalis oil might be suitable for topical treatment of herpetic infections.

Eine Reihe von pflanzlichen Arzneimitteln lassen sich bei den verschiedenen gastrointestinalen Beschwerden und Symptomen von tumorkranken Menschen (Halitosis, Ubelkeit, Erbrechen, dyspeptische Beschwerden, Reizdarmsymptome, Obstipation, Diarrhoe) sinnvoll einsetzen als palliative und supportive Behandlung. Die Basis fUr die Anwendung bilden einerseits therapeutische Empirie und andererseits wissenschaftlich erhobene Daten und klinische Studien, wobei derzeit nur ein kleinerer Teil mit Tumorpatienten durchgefUhrt wurde. Unter diesen Gesichtspunkten stehen vielfAltige Arzneidrogen, phytotherapeutische Zubereitungen und Kombinationen zur VerfUgung: Atherische Ole (z.B. Pfefferminze, Salbei, australischer Teebaum), Bitterstoff-Drogen (z.B. Wermut, Enzian, Artischocke, Iberis), Teezubereitungen und Tinkturen (z.B. Kamille, Brombeere, Frauenmantel, GAnsefinger, Tormentill, Uzara, Szygium, Heidelbeere, Schwarztee), Laxanzien (z.B. Rhabarber, Faulbaum, Senna, Aloe, Leinsamen, Flohsamen) und Fertigarzneimittel wie z.B. Padmed Laxan und Iberogast. Die vorhandenen Erfahrungen und die bisherigen klinischen Studien lassen die mOglichen Vorteile, die geringe HAufigkeit unerwUnschter Wirkungen, aber auch die EinschrAnkungen der phytotherapeutischen Therapien deutlich hervortreten. Insgesamt scheint es, dass das Potential der symptomorientierten Therapie mit pflanzlichen Arzneimitteln in der Behandlung gastrointestinaler Beschwerden bei Patienten mit Tumorerkrankungen unterschAtzt wird.

Tissue cultures of Pimpinella anisum and P. major were used to study the biosynthesis of pseudoisoeugenols. The putative precursors were labelled with 13C with one exception that was labelled with 14C. The incorporation of the label was controlled by 13CNMR and liquid scintil­ lation, respectively. The biosynthetic sequence found was L-phenylalanine, p-cinnamic acid, p-coumaric acid, p-hydroxycoum aric alcohol, p-methoxycoumaric alcohol and anethol. The incorporation rates ranged from 0.5% to 25%.

Unorganized callus and leaf/root-differentiating callus cultures of Pimpinella major have been established in liquid nutrient medium. Their capacity to accumulate rare phenylpropanoids such as epoxy-pseudoisoeugenol tiglate, epoxy-anol tiglate and anol tiglate was compared with that of seedlings and whole plants. The unorganized callus cultures were not able to accumulate any phenylpropanoids. In comparison, the leaf/root-differentiating callus culture promoted the accumulation of epoxy-pseudoisoeugenol tiglate (up to 90 mg/100 g fr.wt.) but not that of anol-derivatives. The accumulated amount of EPT in PMD-SH was comparable with that in plant seedlings.

Aqueous and ethanolic extracts of Salvia officinalis (Lamiaceae) from two different locations (Garden and Swabian Mountains) were examined in vitro on RC-37 cells for their antiviral activity against herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) using a plaque reduction assay. The 50% inhibitory concentrations (IC50) of the extracts for HSV plaque formation were determined in dose-response studies. All extracts tested revealed a high virucidal activity against free HSV-1 and HSV-2. The experimental data exhibited a significant higher sensitivity of HSV against the extracts derived from Garden in comparison with those from Swabian Mountains. The most active one was the Garden 20% ethanol extract with IC50 values of 0.18 microg/ml for HSV-1 and 0.04 microg/ml for HSV-2. In order to identify the mode of antiviral action, the extracts were added to the host cells (RC-37) or viruses at different stages of infection. Independently of the location, both types of herpes viruses were considerably inactivated after treatment with the extracts prior to cell infection. Plaque formation was significantly reduced by >90% for HSV-1 and by >99% for HSV-2. Pretreatment of the host cells with both Garden and Swabian Mountains 20% and 40% ethanolic extracts prior to virus infection revealed a strong reduction of HSV-2 plaque formation by 94% and 70% (Garden) and 99% and 45% (Swabian Mountains), respectively. In time-activity studies with free HSV-1 over a period of 2h, a clearly time-dependent activity was demonstrated whereby the ethanolic extracts of both locations revealed a much higher activity than the aqueous ones. The 20% ethanolic extracts of both locations are of special interest and were effective when added to host cells and free virus. A topical application with a dual mode of action would be ideal against recurrent herpes infections.

Acyclovir-resistant clinical isolates of herpes simplex virus type 1 (HSV-1) were analyzed in vitro for their susceptibilities to essential oils of ginger, thyme, hyssop, and sandalwood. All essential oils exhibited high levels of virucidal activity against acyclovir-sensitive strain KOS and acyclovir-resistant HSV-1 clinical isolates and reduced plaque formation significantly.

Essential oils are widely used in pharmaceutical and cosmetic preparations e.g. as fragrance, active ingredient or penetration enhancer. However, reports on skin absorption are rare. Therefore, the aim of our study was to investigate the capability of terpinen-4-ol, the main compound of Australian tea tree oil (TTO), to permeate human skin. In static Franz diffusion cells permeation experiments with heat separated human epidermis were carried out using infinite dosing conditions and compared to liberation experiments. The flux values of three different semisolid preparations with 5% TTO showed the rank order semisolid O/W emulsion (0.067 microl/cm2 h) > white petrolatum (0.051 microl/cm2 h) > ambiphilic cream (0.022 microl/cm2 h). In comparison to the flux value obtained with the native TTO (0.26 microl/cm2 h), the flux values are remarkably reduced due to the lower amount of terpinen-4-ol. P(app) values for cream (2.74+/-0.06 x 10(-7) cm/s) and native TTO (1.62+/-0.12 x 10(-7) cm/s) are comparable whereas white petrolatum (6.36+/-0.21 x 10(-7) cm/s) and semisolid O/W emulsion (8.41+/-0.15 x 10(-7) cm/s) demonstrated higher values indicating a penetration enhancement. No relationship between permeation and liberation was found.

Herbal drugs are being increasingly used in medical practice, often without appropriate scrutiny of their safety and efficacy. The medicinal product Padma 28 is a fixed combination with Tibetan origin, used in Europe since the 1960s for the symptomatic treatment of circulatory disorders, including those of peripheral arterial occlusive disease (PAOD). We have conducted an analysis of all available data on this herbal drug from published literature as well as from original data we obtained from contacting the authors of published papers, reports and the manufacturer. A total of 19 trials have reported on 2084 patients to date, 444 of whom were in six controlled clinical studies on PAOD. A meta-analysis of five trials showed Padma 28 to increase walking distance by >100m in 18.2% of the patients with verum, versus 2.1% with placebo (P

The virucidal effect of peppermint oil, the essential oil of Mentha piperita, against herpes simplex virus was examined. The inhibitory activity against herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2) was tested in vitro on RC-37 cells using a plaque reduction assay. The 50% inhibitory concentration (IC50) of peppermint oil for herpes simplex virus plaque formation was determined at 0.002% and 0.0008% for HSV-1 and HSV-2, respectively. Peppermint oil exhibited high levels of virucidal activity against HSV-1 and HSV-2 in viral suspension tests. At noncytotoxic concentrations of the oil, plaque formation was significantly reduced by 82% and 92% for HSV-1 and HSV-2, respectively. Higher concentrations of peppermint oil reduced viral titers of both herpesviruses by more than 90%. A clearly time-dependent activity could be demonstrated, after 3 h of incubation of herpes simplex virus with peppermint oil an antiviral activity of about 99% could be demonstrated. In order to determine the mode of antiviral action of the essential oil, peppermint oil was added at different times to the cells or viruses during infection. Both herpesviruses were significantly inhibited when herpes simplex virus was pretreated with the essential oil prior to adsorption. These results indicate that peppermint oil affected the virus before adsorption, but not after penetration into the host cell. Thus this essential oil is capable to exert a direct virucidal effect on HSV. Peppermint oil is also active against an acyclovir resistant strain of HSV-1 (HSV-1-ACV(res)), plaque formation was significantly reduced by 99%. Considering the lipophilic nature of the oil which enables it to penetrate the skin, peppermint oil might be suitable for topical therapeutic use as virucidal agent in recurrent herpes infection.

Objective: To determine the antimicrobial activity of a distillate of Hamamelis (Aqua Hamamelidis ), United States Pharmacopoeia (USP) 23, and urea formulated as a topical dermatological preparation that contains both active ingredients. Methods: Using the simple occlusion test and expanded flora test, we conducted in vivo studies in 15 healthy volunteers. We also performed in vitro studies using the agar diffusion test. Results: The occlusion test and expanded flora test demonstrated significant antimicrobial activity for a product containing the Hamamelis distillate (90%) and urea (5%) among other ingredients. The expanded flora test demonstrated significant antimicrobial activity for both Hamamelis distillate and urea. The simple occlusion test showed the same tendency, but results were not significant. The agar diffusion test showed inhibition of Staphylococcus aureus and Candida albicans , among other organisms. Comparison with earlier studies of chlorhexidine digluconate and fuchsine using the same method showed that the antimicrobial activities of Hamamelis distillate and urea were relatively weak. This finding is supported by the weak inhibitory activity observed in the agar diffusion test (using 100% of the finished dosage form). Conclusion: Formulations of Hamamelis distillate and urea are mainly used for their antiinflammatory, hydrating, and barrier-stabilizing effects in dermatitis maintenance therapy. As bacterial colonization has a central role in the pathogenesis of atopic dermatitis and intertrigo, the antimicrobial activity of such products is considered a welcome, added benefit.

The lipophilic yeast Malassezia pachydermatis is part of the normal skin flora of most warm-blooded organisms. In a number of surveys it could be demonstrated that this yeast species might be involved in different skin diseases like seborrhoeic dermatitis, especially in dogs and cats. In order to look for an alternative therapeutic agent to the commonly used antimycotic and antiseptic synthetic substances the in vitro activity of Australian tea tree oil, the essential oil of Melaleuca alternifolia, against several strains of Malassezia pachydermatis was examined. All tested strains showed remarkably high susceptibility to tea tree oil. With these results the excellent antibacterial activity of tea tree oil is extended to a new group of fungal pathogens colonizing mainly mammals' skin. During the last ten years there was an increasing popularity of tea tree oil containing human health care products. The presented data open up new horizons for this essential oil as a promising alternative agent for topical use in veterinary medicine as well.

A transformed root culture of Coreopsis tinctoria was used to study the biosynthesis of 1′-isobutyryloxyeugenol-4-isobutyrate. Putative precursors labelled with 13 C were fed and incorporation was determined by 13 C NMR spectroscopy. Feeding experiments proved that this compound originates from the l -phenylalanine carbon skeleton without rearrangement of the side-chain. A loss of the carboxyl group and reintroduction of an ‘extra’ carbon atom from l -methionine was excluded. The acyl moieties originate from l -valine.