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The effects of geraniin, a tannin, isolated from Geranium thunbergii Sieb. et Zucc. on the morphology and function of macrophages were studied. Geraniin caused a marked retardation of the recovery from fully spread surface membrane and a highly reorganized cytoskeleton of macrophages, whereas endocytotic activity, phagocytosis and pinocytosis in the cells were significantly inhibited.
BACKGROUND: Rates of synonymous nucleotide substitutions are, in general, exceptionally low in plant mitochondrial genomes, several times lower than in chloroplast genomes, 10-20 times lower than in plant nuclear genomes, and 50-100 times lower than in many animal mitochondrial genomes. Several cases of moderate variation in mitochondrial substitution rates have been reported in plants, but these mostly involve correlated changes in chloroplast and/or nuclear substitution rates and are therefore thought to reflect whole-organism forces rather than ones impinging directly on the mitochondrial mutation rate. Only a single case of extensive, mitochondrial-specific rate changes has been described, in the angiosperm genus Plantago. RESULTS: We explored a second potential case of highly accelerated mitochondrial sequence evolution in plants. This case was first suggested by relatively poor hybridization of mitochondrial gene probes to DNA of Pelargonium hortorum (the common geranium). We found that all eight mitochondrial genes sequenced from P. hortorum are exceptionally divergent, whereas chloroplast and nuclear divergence is unexceptional in P. hortorum. Two mitochondrial genes were sequenced from a broad range of taxa of variable relatedness to P. hortorum, and absolute rates of mitochondrial synonymous substitutions were calculated on each branch of a phylogenetic tree of these taxa. We infer one major, approximately 10-fold increase in the mitochondrial synonymous substitution rate at the base of the Pelargonium family Geraniaceae, and a subsequent approximately 10-fold rate increase early in the evolution of Pelargonium. We also infer several moderate to major rate decreases following these initial rate increases, such that the mitochondrial substitution rate has returned to normally low levels in many members of the Geraniaceae. Finally, we find unusually little RNA editing of Geraniaceae mitochondrial genes, suggesting high levels of retroprocessing in their history. CONCLUSION: The existence of major, mitochondrial-specific changes in rates of synonymous substitutions in the Geraniaceae implies major and reversible underlying changes in the mitochondrial mutation rate in this family. Together with the recent report of a similar pattern of rate heterogeneity in Plantago, these findings indicate that the mitochondrial mutation rate is a more plastic character in plants than previously realized. Many molecular factors could be responsible for these dramatic changes in the mitochondrial mutation rate, including nuclear gene mutations affecting the fidelity and efficacy of mitochondrial DNA replication and/or repair and--consistent with the lack of RNA editing--exceptionally high levels of "mutagenic" retroprocessing. That the mitochondrial mutation rate has returned to normally low levels in many Geraniaceae raises the possibility that, akin to the ephemerality of mutator strains in bacteria, selection favors a low mutation rate in plant mitochondria.
BACKGROUND: To evaluate the antibacterial activity of 21 plant essential oils against six bacterial species. METHODS: The selected essential oils were screened against four gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus vulgaris) and two gram-positive bacteria Bacillus subtilis and Staphylococcus aureus at four different concentrations (1:1, 1:5, 1:10 and 1:20) using disc diffusion method. The MIC of the active essential oils were tested using two fold agar dilution method at concentrations ranging from 0.2 to 25.6 mg/ml. RESULTS: Out of 21 essential oils tested, 19 oils showed antibacterial activity against one or more strains. Cinnamon, clove, geranium, lemon, lime, orange and rosemary oils exhibited significant inhibitory effect. Cinnamon oil showed promising inhibitory activity even at low concentration, whereas aniseed, eucalyptus and camphor oils were least active against the tested bacteria. In general, B. subtilis was the most susceptible. On the other hand, K. pneumoniae exhibited low degree of sensitivity. CONCLUSION: Majority of the oils showed antibacterial activity against the tested strains. However Cinnamon, clove and lime oils were found to be inhibiting both gram-positive and gram-negative bacteria. Cinnamon oil can be a good source of antibacterial agents.
The success of green tea as a cancer preventive is based on evidence that green tea contains tannins and antioxidants, does not show toxicity in humans and has long traditional use in Asia. In the light of this, herbal medicines are now also attracting attention as potential sources of cancer preventive agents. Using the inhibition of TNF-alpha release assay, we studied Acer nikoense (Megusurino-ki in Japanese), one of the herbal medicines. The inhibitory activity of TNF-alpha release was found in the leaf extract rather than the bark extract, and the main active constituents were identified as geraniin and corilagin, which are present in another Japanese traditional herb, Geranium thunbergii (Genno-shoko). The IC50 values of TNF-alpha release inhibition were 43 microM for geraniin and 76 microM for corilagin, whereas that for (-)-epigallocatechin gallate (EGCG) was 26 microM. Treatment with geraniin prior to application of okadaic acid, a tumor promoter on mouse skin initiated with 7,12-dimethylbenz(a)anthracene, reduced the percentage of tumor-bearing mice from 80.0 to 40.0% and the average numbers of tumor per mouse from 3.8 to 1.1 in week 20. Thus, geraniin has slightly weaker inhibitory activity than EGCG. Since geraniin and corilagin have been well investigated as representative tannins, we discuss here the new possibility of classical herbal medicine in the development of preventive agents for cancer and other life-style related diseases.
Mongolian plants were screened for their influence on alpha-amylase activity in mouse plasma. Methanolic extracts of Geranium pratense, Rhodiola rosea, Ribes pullchelum and Vaccinium uliginosum inhibited the enzyme activity in isolated mouse plasma by greater than 40% and the effect was concentration dependent. Vaccinium uliginosum also showed a depressive effect on elevation of postprandial blood glucose to some extent.
Treatment of peritoneal macrophages with geraniin, isolated from Geranium funbergii, markedly induced the phagocytosis of living yeasts. Marked increases in phagocytosis and acid phosphatase activity in macrophage lysates were observed 24 hr after the beginning of geraniin treatment. As observed by electron microscopy, macrophages that had been treated for 24 hr with geraniin had a markedly thickened surface layer which was positive to ruthenium red, compared to the control cells. In addition, geraniin treatment of macrophages appeared to induce remarkably large mitochondria, more coated pits and prominent lysosomal granules. In conclusion, the stimulation of phagocytosis and acid phosphatase activity of macrophages by geraniin treatment may involve alterations of the plasma membrane and cytoplasmic reorganization.
The present study was conducted to further explore plant-derived essential oils that possess an anticonflict effect using the Geller type conflict test in ICR mice. The benzodiazepine anxiolytic diazepam increased the response (lever pressing) rate during the alarm period (i.e., an anticonflict effect), but the 5-HT1A partial agonist buspirone did not. Oils of juniper, cypress, geranium and jasmine did not produce any effect in this test. Frankincense oil decreased the response rate during the safe period at 1600 mg/kg, but did not exhibit any effect on the response rate during the alarm period. In contrast, lavender oil increased the response rate during the alarm period in a dose-dependent manner in the same manner as diazepam. These results indicate that not only rose oil but also lavender oil possess an anticonflict effect in mice.
The aim of this study was to monitor the effect of sudden frost on the photosynthetic electron transport chain in the leaves of various plant species using the thermoluminescence (TL) technique. A short period of freezing caused a decrease in the afterglow (AG) band in young maize leaves, with a slight upshift in the maximum temperature. The B band induced by far-red (FR) illumination started to decrease at a significantly lower temperature. The flash-induced B band also showed a substantial decrease in intensity after short preliminary freezing. In contrast to other species, for which there was always a well-detectable TL signal even after relatively drastic freezing, there was no TL signal at all in geranium below a threshold temperature. The behavior of the FR-induced TL curve in cucumber plants was a mixture of that found in wheat or pea, on the one hand, and maize, on the other: the AG band gradually decreased with decreasing temperature and finally totally disappeared, as in maize. The FR-induced B band showed an upshift after freezing. These results suggest that AG is a normal component of TL bands induced not only by FR, but also by single turnover flash.
200 University of Wolverhampton undergraduates rank-ordered samples of aromatic oils commonly used in complementary medicine in terms of their concentration in the air above an oil-soaked cotton ball. Each participant was assigned the task of discriminating between 5 microl, 10 microl, and 20 microl of oil absorbed onto cotton balls. 25 participants assessed each oil, and 8 oils were used. Cardamom, Rosemary, and Ylang Ylang were highly discriminable; however, discrimination of different concentrations of Chamomile, Cyprus, Geranium, Jasmine, and Lavender did not significantly differ from chance. These data provide useful indices for choosing aromatic oils for research purposes.
The mosquito repellent efficacy of New Mountain Sandalwood Mosquito Sticks (containing 0.5% w/w essential oils) and New Mountain Sandalwood Botanical Repellent (containing soybean and geranium oils) was assessed. Tests were conducted in the field with 4 volunteers in a wooded area near Cairns, North Queensland, Australia. Predominant biting species were Verrallina funerea and Ve. lineata. A pair of burning Mosquito Sticks immediately upwind of the subject (acting as an area repellent) provided a 73.1% mean reduction in mosquito landing and probing over the 3-h test period. The Botanical Repellent and a DEET-based control were both 100% effective in preventing mosquito probing for 3 h. These data are consistent with other studies of area repellents in that such products provide significant protection from mosquito bites, albeit inferior to the protection provided by topically applied repellents.
A staining solution containing alcian blue 8GX, Bismarck brown Y and safranin O was prepared with 0.1 M sodium acetate buffer, pH 5.0. Paraffin was extracted with MicroClear solvent from 10 microm tissue sections mounted on slides. Paraffin solvent was removed by rinsing with isopropanol, and tissues were air dried. Slides with bare dry tissue sections were immersed in the triple stain and structures could be distinguished within 30 min as follows: nonlignified cell walls, blue; lignified cell walls, nuclei and chloroplasts, red; and cuticle, brown or yellow-brown. Excess staining solution was removed by rinsing with tap water, and the tissues were air dried again. Coverslips were affixed with resin over the stained dry tissues. This novel procedure was tested with immature tomato fruit, mature apple fruit, and various leaf and stem specimens of dogwood, laurel, pawpaw, poinsettia and zonal geranium.
The paper presents a study of the associated effect of acyclovir and a plant extract from Calendula officinalis, Actium lappa and Geranium robertianum. We studied a number of 52 patients suffering of herpetic keratitis. Better results in resolving complains and faster healing of ulceration were obtained using the associated treatment then the usual acyclovir treatment only.
Methanolic-aqueous extracts of 70 plants were investigated for their ability to inhibit HIV-1 reverse transcriptase activity in vitro. Two thirds of the extracts screened showed more than 50% inhibition. Two extracts inhibited the enzyme completely while four exhibited more than 90% inhibition. Tannins as nonspecific HIV-1 RT inhibitors were detected and removed from the extracts. The IC50 values of the most potent extracts after the removal of tannins for the HIV-1 RT inhibition are as follows: Sambucus racemosa 0.017 mg/ml and Geranium phaeum 0.067 mg/ml. Daunomycine was chosen as a standard substance in the non-radioactive immuno assay used for screening. As a result from the future isolation and characterization of these compounds, new leading structures are expectable.
CONTEXT: Interest in the use of alternative therapies to reduce anxiety in patients undergoing medical interventions is increasing. We sought to assess the effectiveness of aromatherapy involving essential oils in reducing preoperative anxiety in women undergoing abortions. SETTING: An urban, free-standing abortion clinic in Vancouver, BC. PATIENTS: 66 women waiting for surgical abortions. DESIGN: A double blind, randomized trial. INTERVENTION: Ten minutes spent sniffing a numbered container with either a mixture of the essential oils vetivert, bergamot, and geranium (treatment arm) or a hair conditioner (placebo). OUTCOME MEASURES: Anxiety was measured before and after the intervention by using a verbal anxiety scale from 0 to 10. RESULTS: The anxiety score was reduced by 1.0 point (5.0 to 4.0) in the aromatherapy group and by 1.1 points (6.1 to 5.0) in the placebo group (P = 0.71). The 95% CI on the 0.1 greater decrease in anxiety for the placebo group extends from 0.55 less (favors aromatherapy) to 0.75 greater (favors placebo). CONCLUSION: Aromatherapy involving essential oils is no more effective than having patients sniff other pleasant odors in reducing preprocedure anxiety.
OBJECTIVE: To assess the repellency effect of three local plants; fever tea (Lippia javanica), rose geranium (Pelargonium reniforme) and lemon grass (Cymbopogon excavatus) against laboratory reared Anopheles arabiensis mosquitoes. DESIGN: A laboratory experimental study. SETTING: Mpumalanga Province, South Africa. SUBJECTS: Three adult male volunteers. MAIN OUTCOME MEASURES: Affordable alternatives to synthetic repellents against biting of Anopheles arabiensis mosquitoes. RESULTS: All three alcohol plant extracts provided significantly more protection (p = 0.012) than alcohol control. The alcohol plant extract of L. javanica provided 76.7% protection against An. arabiensis after a four hour period, and C. excavatus and P. reniforme provided 66.7% and 63.3% protection for three hours, respectively. At five hours post application only L. javanica alcohol extract provided appreciable protection (59.3%) against An. arabiensis. CONCLUSION: The results of this study indicate that L. javanica, P. reniforme and C. excavatus protect against An. arabiensis mosquito bites with the repellent effect of L. javanica lasting significantly longer than that of the other two plants.
A comparison of 5 commercial mosquito repellents was made on adult male and female volunteers in laboratory trials. The products tested in forms of cream or lotion included 4 natural oil formulations (containing citronella, clover, eucalyptus, geranium, lavender, peppermint, sandalwood, thyme, etc.) and 1 synthetic chemical repellent containing 10% KBR 3023). Natural oil products showed essentially poor or no repellency against Ae, aegypti: the protection times were less than or equal to 1 hour. Only the synthetic repellent based on KBR 3023 provided satisfactory defence to human volunteers.
Geranyl acetate (3,7-dimethyl-2,6-octadiene-1-ol acetate) is a colorless liquid prepared by fractional distillation of selected essential oils or by acetylation of geraniol. It is a natural constituent of more than 60 essential oils, including Ceylon citronella, palmarosa, lemon grass, petit grain, neroli bigarade, geranium, coriander, carrot, and sassafras. Geranyl acetate is used primarily as a component of perfumes for creams and soaps and as a flavoring ingredient. On the U.S. Food and Drug Administration's list of substances "generally recognized as safe," the Food Chemicals Codex (1972) specifies that geranyl acetate must contain at least 90% total esters. Carcinogenesis studies of food-grade geranyl acetate (containing approximately 29% citronellyl acetate) were conducted by administering the test chemical in corn oil by gavage to groups of 50 male and 50 female F344/N rats at doses of 1,000 or 2,000 mg/kg body weight and to groups of 50 male and 50 female B6C3F1 mice at doses of 500 or 1,000 mg/kg. Doses were administered five times per week for 103 weeks. Groups of 50 rats and 50 mice of each sex received corn oil by gavage on the same dosing schedule and served as vehicle controls. The cumulative toxicity of geranyl acetate in the 2-year study was indicated by the significantly shorter survival of high dose male rats (control, 34/50; low dose, 29/50; high dose, 18/50) and of high dose male mice (control, 31/50; low dose, 32/50; high dose, 0/50) and of dosed female mice (38/50; 15/50; 0/50) when compared with controls. Throughout most of the 2-year study, mean body weights of high dose rats and mice of each sex were lower than those of the controls. The occurrence of retinopathy or cataracts in the high dose male rats and low dose female rats as compared with the controls does not appear to be related to the administration of geranyl acetate but rather the proximity of the rats to fluorescent light. The incidence of retinopathy or cataracts (combined) was: males: control, 0/50, 0%; low dose, 1/50, 2%; high dose, 11/50, 22%; females: control, 1/50, 2%; low dose, 13/50, 26%; high dose, 2/50, 4%. Kidney tubular cell adenomas, an uncommon tumor type, were found in 2/50 (4%) low dose male rats. The historical incidence of male corn oil gavage control F344/N rats with kidney tumors is 1/250 (0.4%) at this laboratory and 4/998 (0.4%) in the program. Squamous cell papillomas in the skin were increased marginally in low dose male rats (control, 0/50; low dose, 4/50, 8%; high dose, 1/50, 2%). In addition, one low dose male rat had a squamous cell carcinoma of the skin. The incidence of low dose male rats with either squamous cell papillomas or carcinomas was greater (P<0.05) in comparison with the controls. The historical incidence of squamous cell papillomas or carcinomas (combined) in gavage control male F344/N rats is 3.6% (9/250) at this laboratory and 2.5% (25/999) throughout the program. The incidence of all epidermal tumors was not significantly elevated in dosed male rats relative to controls (control, 3/50, 6%; low dose, 6/50, 12%; high dose, 1/50, 2%). All high dose (1,000 mg/kg) male and female mice were dead by week 91 as a result of accidentally being administered 2,800 mg/kg for 3 days during week 91; survival of low dose and control male mice was comparable. Survival of high dose male and dosed female mice may have been inadequate for the detection of late-appearing tumors. No evidence of any carcinogenic effect was found in either low or high dose mice of either sex. An infection of the genital tract was probably responsible for the deaths of 14/22 control and 8/32 low dose female mice before the end of the study. Cytoplasmic vacuolization was increased in the liver and in the kidney of male and female mice and was considered to be compound related (liver-- male: control, 1/50, 2%; low dose, 7/50, 14%; high dose, 47/50, 94%; female: 1/50, 2%; 27/50, 54%; 46/50, 92%; kidney or kidney tubule--male: 0/50; 0/50; 41/50, 82%; female: 0/50; 24/49, 49%; 37/50, 74%). Under the conditions of these studies, geranyl 4%; 46/50, 92%; kidney or kidney tubule--male: 0/50; 0/50; 41/50, 82%; female: 0/50; 24/49, 49%; 37/50, 74%). Under the conditions of these studies, geranyl acetate was not carcinogenic for F344/N rats or B6C3F1 mice of either sex; however, the reduced survival observed in high dose male rats, high dose male mice, and high and low dose female mice lowered the sensitivity of these studies for detecting neoplastic responses in these groups. In male rats the marginal increases of squamous cell papillomas of the skin and tubular cell adenomas of the kidney may have been related to administration of geranyl acetate. Levels of Evidence of Carcinogenicity: Male Rats: Negative Female Rats: Negative Male Mice: Negative Female Mice: Negative
This work presents the results of the test performed on rats to evaluate the carcinogenic effect of 4 synthetic amphiboles compared to that of the natural amphibole--crocidolite. The dose of the magnesium amphibole (Na2Mg6Si8(OH)2) administered to the animals contained 240 x 10(6) respirable fibres; the corresponding value for the nickel amphibole (Na2Ni6Si8O22(OH)2) was 339 x 10(6), for the cobalt amphibole (Na2Co6Si8O22(OH)2)--1000 x 16(6) for the geranium amphibole (Na2Mg6Ge8(OH)2)--250 x 10(6), and of the natural crocidolite amphibole (Na2Fe2Fe3Si8O22(OH)2) x 380 x 10(6) respirable fibres. The control animals (rats) received physiological NaCl solution. The number of peritoneal mesotheliomas following single intraperitoneal administration of 20 mg of the dust was adapted to be the measure of the carcinogenic activity of the dust. 3 synthetic (magnesium, cobalt and nickel) amphiboles and crocidolite caused development of malignant peritoneal mesothelioma in 11.1% to 71% rats. The results show that there is a relationship between the chemical composition of the synthetic amphiboles and their carcinogenic effect. Out of 4 investigated synthetic amphiboles, the magnesium amphibole, which contained magnesium and silicon, displayed most severe carcinogenic effect. The synthetic amphiboles containing either silicon and cobalt or silicon and nickel displayed 8.3 and 6.2 times weaker ability to induce peritoneal mesothelioma.