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J Reichling

Publications and source records attributed to J Reichling.

At least 37 records · Page 2Linked to original sources
PubMed2002

Comparative investigation of the antimicrobial activity of PADMA 28 and selected European herbal drugs.

OBJECTIVE: PADMA 28 is a multicompound preparation of 20 herbs, calcium sulphate, and camphor, derived from Tibetan medicine. It is usually used in the treatment of peripheral circulatory disorders, accompanied by the symptoms tingling, formication, heaviness and tenseness in arms and legs, numbness in hands and feet, and cramps in the calf. Recently, the question of whether appropriate preparations of PADMA 28 also exhibit antibacterial and antimycotic activity has often been raised. As there are as yet no experimental findings that answer this question, an in vitro study was carried out. In a parallel survey we investigated the antimicrobial properties of 5 herbal drugs which are commonly used in the traditional European folk medicine for the topical treatment of mild skin infections, wounds and eczematous skin lesions. METHODS: The minimum inhibitory concentrations (MIC) and the minimum bactericidal concentrations (MBC) of alcohol-based (tinctures) and aqueous (teas) herbal drug preparations were determined in vitro by a broth microdilution method for 5 Gram-positive and 5 Gram-negative bacteria, as well as the yeast Candida albicans. RESULTS: The aqueous and alcohol-based PADMA 28 preparations as well as the corresponding preparations of the European herbal drugs showed an antibacterial effect against Gram-positive bacteria in vitro. These bacteria revealed a somewhat higher sensitivity to the teas prepared from the European herbal drugs (MIC: 1.3-20.0 mg/ml) than to the aqueous preparations of PADMA 28 (MIC: 5.0-40.0 mg/ml). The better antibacterial activity of the European herbal drugs is probably based on their relatively high amount of tanning agents. On the other hand, all tested plant preparations inhibited not at all or only insufficiently the growth of the Gram-negative bacteria tested and that of Candida albicans. The ethanolic PADMA 28 tinctures showed an improved inhibitory effect on the Gram-positive bacteria (MIC: 0.38-1.51% tincture or 0.38-1.51 mg PADMA 28/ml) compared with the aqueous preparations; this effect is comparable to the ethanolic tinctures of the tested European herbal drugs (MIC: 0.4-1.6/3.2% tincture or 0.4-1.6/3.2 mg herbal drug/ml). CONCLUSION: All tested tea preparations and alcoholic tinctures of PADMA 28 as well as those of the selected European herbal drugs exhibited evident antibacterial effects against Gram-positive bacteria in vitro. On the other hand, except for Klebsiella pneumoniae, all Gram-negative bacteria tested and the yeast Candida albicans were insensitive against the different aqueous and alcohol-based plant extracts.

Anti-Bacterial Agents↗
PubMed2002

Aqueous ethanolic extract of St. John's wort (Hypericum perforatum L.) induces growth inhibition and apoptosis in human malignant cells in vitro.

Extracts of Hypericum perforatum (St. John's wort) are widely and effectively used in the treatment of mild to moderate depression. In addition, hypericin, a component of Hypericum p. extracts, exhibits light-dependent phototoxic properties and can be used in phototherapy. We therefore investigated the cytotoxic activity of two total Hypericum p. extracts, namely from fresh and dried plants in the dark and after exposure to 7.5 J/cm2 white light illumination and compared it with the effect of hypericin on K562, U937, LN229 glioblastoma cell lines and normal human astrocytes. The chemical toxicity of non-illuminated Hypericum p. extracts in the cells tested is low as expressed by a LC50 between 1.9-4.1 mg/ml, which corresponds to 10.3-17.3 microM hypericin and 114.4-190.7 microM hyperforin after 48 h treatment. Hypericum p. extracts induced dose-dependent growth arrest of human malignant cells in the absence of illumination with GI50 values between 0.43-1.77 mg/ml (2.3-9.7 microM hypericin, 26.1-106.7 microM hyperforin) for the fresh plant extract and 0.59-3.03 mg/ml (2.5-12.8 microM hypericin, 24.2-124.7 microM hyperforin) for the dried extract. The growth inhibitory effect of fresh Hypericum p. extract was more pronounced in leukemia cell lines K562 and U937, the GI50 concentrations being about 7-fold lower than the corresponding LC50 for the cell lines K562 and U937, but almost the same as the LC50 for LN229 and NHA cells. GI50 (microgram/ml) for tumor cell lines K562 and U937 (432 and 799) established after 48 h differed significantly (p < 0.05) from those of LN229 and normal human astrocytes (1767 and 2900). The light-exposed extracts were more toxic, their LC50 and GI50 values were reduced to values corresponding to LC50 concentration of 3.7-7.4 microM and a GI50 of 1.3-3.5 microM for phototoxic hypericin. After exposure to light, there was a significant difference (p = 0.006) between the GI50 of glioblastoma LN229 cells (582 micrograms/ml) and normal human astrocytes (1050 micrograms/ml). Morphological examination by light microscopy and phosphaditylserine exposure on the outer plasma membrane investigated by Annexin V-binding with flow cytometry after 24 h confirmed that Hypericum p. extracts caused apoptosis of treated cells without exposure to light. Hypericum p. extracts derived from fresh herbs and from dried herbs which differ in their levels of phloroglucinols (hyperforin and adhyperforin) were compared. The hyperforin content of fresh St. John's wort extract exceeded that of dried plant extract by 47% and the GI50 values of fresh plant extract were 73%, 77% and 58% of those established for dried extract in the three malignant cell lines K562, U937 and LN229 in the dark (p < 0.05). Under white light (7.5 J/cm2), both extracts exerted comparable growth inhibitory and apoptosis inducing effects due to the phototoxicity of hypericin, the corresponding concentrations of which were in the range of 1.3-3.5 microM. The data reported in this study suggest that illumination is not essential for the growth inhibitory and apoptotic effects of Hypericum p. extracts, but light activation potentiates them. Furthermore, the constituent hyperforin is at least partly responsible for these effects in the dark.

Annexin A5↗
PubMed2001

A current review of the antimicrobial activity of Hypericum perforatum L.

A petrolether extract of the areal parts of Hypericum perforatum L. was reported to be active against gram-positive bacteria. Hyperforin, a phloroglucin derivative was shown to be the antimicrobial principle. Hyperforin exhibited an excellent effect against methicillin-resistant strains of Staphylococcus aureus with a MIC value of 1.0 microg/ml. A butanol fraction of St. John's Wort revealed anti-Helicobacter pylori activity with MIC values ranging between 15.6 and 31.2 microg/ml. Recently, hydrous solutions of Hypericum perforatum teas were found to be antimicrobially effective against gram-positive bacteria with special activity towards methicillin-restistant strains of Staphylococcus aureus (MIC values: 1.3 to 2.5 mg herb/ml).

Anti-Bacterial Agents↗
PubMed2001

[Dyspeptic pain and phytotherapy--a review of traditional and modern herbal drugs].

Gastrointestinal complaints rank among the most frequently reasons why people asking for medical advice. About 15-30% of the adult patients suffer from different various functional dyspeptic conditions. The therapy of functional gastrointestinal disorders is one of the domains of phytotherapeutic treatments. From ancient times on, bitter herbal drugs played a very important role in the therapy of patients with dyspeptic symptoms. The mechanisms of action of the bitters are not completely understood. But there are indications that they sensorially stimulate at even very small concentrations sensorially the secretion of the stomach as well as the digestive glands and strengthen the smooth musculature of the digestive tract (via the gustatory system, N. vagus and the enteric nervous system). Across the enteral nervous system the strengthened digestive tract seems to stimulate the CNS, leading to a general tonification. At higher dosages bitters probably directly affect the mucous membranes of the stomach and the bowel. Bitters often are combined with essential oils (some volatile oils as aromatic bitters, drug combinations of a volatile oil with a bitter). Essential oils act primarily as spasmolytics, carminatives and local anesthetics. In the last years several controlled studies were carried out with phytotherapeutic combinations (e.g. with Iberis amara, caraway oil, peppermint oil, curcuma extract, ginger extract) in which the herbal drugs proved to be superior compared to placebo and were as effective as prokinetics (studies according to evidence-based medicine). The traditional phytotherapeutic approach is based upon the illness- as well as the patient-related investigations referring to the effectiveness of bitter, acrid- and essential-oil drugs. Such a treatment is supported by a rich amount of various of kinds of individual empirical experience (experience-based phytotherapy). Important traditional medical systems like the Traditional Chinese Medicine, the Ayurvedic Medicine as well as the European 'Humoral Medicine' consider different aspects of the sick human being, like the constitution of the patient (holistic approach), and take qualities of herbal drugs, vegetarian food, and spices into account for therapeutic purposes.

Drugs, Chinese Herbal↗
PubMed2001

Antiviral activity of Australian tea tree oil and eucalyptus oil against herpes simplex virus in cell culture.

The antiviral effect of Australian tea tree oil (TTO) and eucalyptus oil (EUO) against herpes simplex virus was examined. Cytotoxicity of TTO and EUO was evaluated in a standard neutral red dye uptake assay. Toxicity of TTO and EUO was moderate for RC-37 cells and approached 50% (TC50) at concentrations of 0.006% and 0.03%, respectively. Antiviral activity of TTO and EUO 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 TTO for herpes simplex virus plaque formation was 0.0009% and 0.0008% and the IC50 of EUO was determined at 0.009% and 0.008% for HSV-1 and HSV-2, respectively. Australian tea tree oil exhibited high levels of virucidal activity against HSV-1 and HSV-2 in viral suspension tests. At noncytotoxic concentrations of TTO plaque formation was reduced by 98.2% and 93.0% for HSV-1 and HSV-2, respectively. Noncytotoxic concentrations of EUO reduced virus titers by 57.9% for HSV-1 and 75.4% for HSV-2. Virus titers were reduced significantly with TTO, whereas EUO exhibited distinct but less antiviral activity. In order to determine the mode of antiviral action of both essential oils, either cells were pretreated before viral infection or viruses were incubated with TTO or EUO before infection, during adsorption or after penetration into the host cells. Plaque formation was clearly reduced, when herpes simplex virus was pretreated with the essential oils prior to adsorption. These results indicate that TTO and EUO affect the virus before or during adsorption, but not after penetration into the host cell. Thus TTO and EUO are capable to exert a direct antiviral effect on HSV. Although the active antiherpes components of Australian tea tree and eucalyptus oil are not yet known, their possible application as antiviral agents in recurrent herpes infection is promising.

Antiviral Agents↗
PubMed2001

[Herbal remedies in veterinary phytotherapy].

Phytotherapy is based on the use of herbal remedies (phytopharmaceuticals) for therapy and prophylactic measures of illness in humans and animals. Animal owners as well as veterinarians (surgeons) are more and more interested in veterinary phytotherapy. The following review explains fundamentals of veterinary phytotherapy as well as the production, application and possible side-effects of veterinary herbal remedies (veterinary phytopharmaceuticals).

Animal Diseases↗
PubMed2000

Treatment of corneal neovascularization with dietary isoflavonoids and flavonoids.

The purpose of this study was to investigate the use of dietary isoflavonoids and flavonoids for the treatment of ocular neovascularization. Corneal blood vessels were induced by intrastromal implantation of pellets containing bFGF. Isoflavonoids and flavonoids (Genistein, Fisetin and Luteolin) were dissolved in a microemulsion to increase bioavailability and applied topically in concentrations between 0.5 and 1 ng ml(-1). Corneal neovascularization was quantified under the microscope. In comparison to control eyes, all three substances significantly inhibited corneal neovascularization (P < or = 0.05). Fisetin had the strongest effect followed by Genistein and Luteolin. No significant topical side effects were observed. We concluded that the isoflavonoid Genistein and two structurally related flavonoids are potent inhibitors of corneal angiogenesis in vivo. The wide distribution of the flavonoids in the plant kingdom together with the presented results suggests that flavonoids may contribute to the preventive effect of a plant-based diet on neovascular disease of the eye.

Administration, Topical↗
PubMed2000

In vitro effect of essential oils and isolated mono- and sesquiterpenes on Leishmania major and Trypanosoma brucei.

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.

Animals↗
PubMed2000

Effect of Australian tea tree oil on the viability of the wall-less bacterium Mycoplasma pneumoniae.

In vitro assays using a variety of essential oils revealed a particularly high antibacterial effect of Australian tea tree oil (TTO) on a great number of gram-negative and gram-positive bacteria of unrelated phylogenetic origin. In the present study, the susceptibility of cell wall-less bacteria such as the human pathogenic bacterium Mycoplasma pneumoniae to Australian tea tree oil was examined. The minimum inhibitory concentration (MIC) was determined to be 0.006% (v/v) TTO for the wild type and to 0.003% (v/v) TTO for mutants of M. pneumoniae which lost the ability to adhere to host cells (cytadherence-negative). The MIC and the MBC (minimum bactericidal concentration) for M. pneumoniae are 100 times lower than those for all other eubacteria tested. Electron microscopy with negatively stained cells as well as with ultrathin sections revealed a tendency to ovoid or round cells after oil treatment whereas the untreated cells of the wild type exhibit a flask-shaped morphology with a tip-like structure at one pole of the cell. The integrity of the mycoplasmal membrane seems not to be affected by TTO since no leakage of the Mycoplasma cell was observed after oil treatment. In the HET-CAM test TTO did not show any visible signs of irritation in concentrations less than 25%. Although the active component in TTO that has anti-mycoplasmal activity is not known, it seems very promising to use TTO tentatively for mouth washing and inhalation in case of Mycoplasma-pneumoniae-infection.

Animals↗
PubMed1999

Degradation products of monoterpenes are the sensitizing agents in tea tree oil.

BACKGROUND: Patients using tea tree oil (TTO) topically may become sensitized to this natural remedy. More than 30 cases have been documented in the literature since 1991. OBJECTIVE: Freshly distilled, as well as oxidized TTO, some fractions, and single constituents were used for experimental sensitization in guinea pigs. TTO was stored on a window sill to study the influence of light, oxygen, and warmth. The oxidized oil and different fractions were devoted to experimental sensitization in guinea pigs to determine their sensitizing potency. Fifteen constituents were patch tested in TTO-sensitive patients to find how many may play a role as contact allergens. METHODS: Guinea pigs were sensitized by a modified FCA-method (Freund's complete adjuvant) with freshly distilled TTO, oxidized TTO, the monoterpene and sesquiterpene fraction, and 1, 8-cineole. TTO-sensitive patients were tested with 15 typical constituents and degradation products. Gas chromatographic analysis was used to detect degradation products of the deteriorated TTO. RESULTS: Fresh TTO was revealed to be a very weak sensitizing material whereas oxidized TTO was 3 times stronger. The monoterpene fraction showed to be a stronger sensitizer than the sesquiterpene fraction. All 11 patients reacted mostly with a ++-plus or even a -plus reaction to alpha-terpinene, terpinolene and ascaridol. alpha-Phellandrene became positive in four patients, myrcene in only two. Gas chromatographic analyses showed that the formation of peroxides increased within 4 days from less than 50 to more than 500 ppm. Peroxides, epoxides and endoperoxides were formed. Deterioration products of alpha-terpinene were found to be mainly p-cymene, ascaridol, isoascaridol, a ketoperoxide, and colorless crystals that likely were 1,2,4-trihydroxy menthane. The p-cymene content increased dramatically from 2% to 11.5%. alpha- and gamma-terpinene, as well as terpinolene, were reduced to one half of their former concentration. Ascaridol and isoascaridol have never before been found in TTO. CONCLUSION: Tea tree oil kept in open and closed bottles or other containers undergoes photooxidation within a few days to several months, leading to the creation of degradation products that are moderate to strong sensitizers. Peroxides, epoxides and endoperoxides, like ascaridol and 1,2,4-trihydroxy menthane, are formed. These must be considered responsible for the development of allergic contact dermatitis seen in individuals treating themselves with the oil. A test series with 15 characteristic constituents is recommended for patch testing.

Adult↗
PubMed1999

In vivo significance of ICAM-1--dependent leukocyte adhesion in early corneal angiogenesis.

PURPOSE: Numerous investigations have stressed the significance of leukocytes in early angiogenesis. Leukocytes invade the cornea, and the location of their extravasation corresponds to the site of vessel ingrowth. The interactions between leukocytes and vascular endothelium are mediated by various proteins, including adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1). In this study, the role of ICAM-1 during early corneal angiogenesis was evaluated in vivo. METHODS: Corneal neovascularization was induced in New Zealand White rabbits by use of intrastromal pellets containing 750 ng vascular endothelial growth factor (VEGF). The fluorescent dye rhodamine 6G was used to stain leukocytes in vivo. Leukocyte adhesion and vessel growth were quantified in vivo by high-resolution fluorescence angiography. To inhibit ICAM-1 interactions a microemulsion containing anti-ICAM-1 antibody was applied topically. RESULTS: Limbal vessels showed increased leukocyte adhesion 24 hours after pellet implantation: The number of rolling and sticking leukocytes was significantly increased compared with the number in control animals (P < 0.01). Treatment with anti-ICAM-1 antibody resulted in reduced leukocyte sticking and increased leukocyte rolling. The area covered by new blood vessels was significantly diminished in eyes treated with anti-ICAM-1 (P < 0.05). CONCLUSIONS: The results support the hypothesis that ICAM-1-mediated leukocyte adhesion is a key event in early angiogenesis. This model may serve for investigation of the significance of adhesion molecules by in vivo observation and quantification.

Animals↗
PubMed1999

Comparative study on the in vitro antibacterial activity of Australian tea tree oil, cajuput oil, niaouli oil, manuka oil, kanuka oil, and eucalyptus oil.

To compare the antibacterial activity of the Australian tea tree oil (TTO) with various other medicinally and commercially important essential myrtaceous oils (cajuput oil, niaouli oil, kanuka oil, manuka oil, and eucalyptus oil) the essential oils were first analysed by GC-MS and then tested against various bacteria using a broth microdilution method. The highest activity was obtained by TTO, with MIC values of 0.25% for Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Salmonella choleraesuis, Shigella flexneri, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, S. saprophyticus, and S. xylosus. It is noteworthy that manuka oil exhibited a higher activity than TTO against gram-positive bacteria, with MIC values of 0.12%. Both TTO and manuka oil also demonstrated a very good antimicrobial efficacy against various antibiotic-resistant Staphylococcus species. Pseudomonas aeruginosa was resistant to all essential oils tested, even at the highest concentration of 4%.

Anti-Bacterial Agents↗
PubMed1995

Biosynthesis of pseudoisoeugenols in tissue cultures of Pimpinella anisum. Phenylalanine ammonia lyase and cinnamic acid 4-hydroxylase activities.

The genus Pimpinella contains pseudoisoeugenols, phenylpropanoids with a rare 2,5-dioxy substitution pattern on the phenyl ring. To study the biosynthesis of these compounds, we set up a leaf-differentiating tissue culture of Pimpinella anisum. These cultures mainly produce epoxy-pseudoisoeugenol-(2-methylbutyrate). To corroborate the biosynthetic pathway of epoxy-pseudoisoeugenol-(2-methylbutyrate) as proposed on the basis of investigations with 13C/14C-labelled precursors, the key steps of the pathway were investigated at an enzyme level. Experiments with cell-free homogenates clearly revealed that L-phenylalanine is converted to (E)-cinnamic acid by phenylalanine ammonia lyase and that (E)-cinnamic acid is converted to p-coumaric acid by cinnamic acid 4-hydroxylase. L-2-aminooxy-3-phenylpropionic acid, an analogue of L-phenylalanine, inhibited the incorporation of L-[3'-13C]phenylalanine into epoxy-pseudoisoeugenol-(2-methylbutyrate). Up to 2% of the precursor DL-[3'-13C]phenyllactate was incorporated into epoxy-pseudoisoeugenol-(2-methylbutyrate). Inhibition experiments with oxalacetic acid clearly showed that cinnamic acid is not formed by dehydration of phenyllactic acid in this leaf-differentiating tissue culture of P. anisum.

Cell-Free System↗
PubMed1994

1'-Hydroxyeugenol- and coniferyl alcohol derivatives as effective inhibitors of 5-lipoxygenase and Cu(2+)-mediated low density lipoprotein oxidation. Evidence for a dual mechanism.

1'-Hydroxyeugenol- and epoxy-Z-coniferyl alcohol esters from Coreopsis species as well as synthetic derivatives of these natural compounds were examined as lipoxygenase inhibitors and as LDL (low density lipoprotein)-stabilizing agents. Most of the compounds displayed inhibitory activity on the formation of leukotrienes (LTB4 and LTC4) in a cellular (RBL-1 cells) assay as well as in a cell-free 5-lipoxygenase assay at concentrations of 4-24 mumol/l. No effect of selected compounds was observed on mammalian lipoxygenases with other specificity (12- and 15-lipoxygenase). The more lipophilic derivatives also effectively reduced Cu(2+)-mediated oxidation of LDL. The findings are discussed on the base of structure-activity relationships.

Animals↗