Flavonoids from lemon balm (Melissa officinalis L., Lamiaceae).
Six flavonoids have been isolated from the leaves of lemon balm (Melissa officinalis L., Lamiaceae). Their structures were determined on the basis of spectral data (UV, 1R, 1H NMR, 13C NMR and FAB MS) as luteolin, luteolin 7-O-beta-D-glucopyranoside, apigenin 7-O-beta-D-glucopyranoside, luteolin 7-O-beta-D-glucuronopyranoside, luteolin 3'-O-beta-D-glucuronopyranoside and luteolin 7-O-beta-D-glucopyranoside-3'-Obeta-D-glucuronopyranoside. The last three glycosides have been found in lemon balm for the first time and luteolin 7-O-beta-D-glucopyranoside-3'-O-beta-D-glucuronopyranoside is a new compound found in plants. (+info)
Melissa officinalis extract in the treatment of patients with mild to moderate Alzheimer's disease: a double blind, randomised, placebo controlled trial.
OBJECTIVE: To assess the efficacy and safety of Melissa officinalis extract using a fixed dose (60 drops/day) in patients with mild to moderate Alzheimer's disease. DESIGN: A four month, parallel group, placebo controlled trial undertaken in three centres in Tehran, Iran. METHODS: Patients with mild to moderate Alzheimer's disease aged between 65 and 80 years (n = 42; 18 women, 24 men) with a score of >or= 12 on the cognitive subscale of Alzheimer's disease assessment scale (ADAS-cog) and +info)
Modulation of mood and cognitive performance following acute administration of single doses of Melissa officinalis (Lemon balm) with human CNS nicotinic and muscarinic receptor-binding properties.
Melissa officinalis (Lemon balm) is a herbal medicine that has traditionally been attributed with memory-enhancing properties, but which is currently more widely used as a mild sedative and sleep aid. In a previous study it was demonstrated that a commercial Melissa extract led to dose-specific increases in calmness, and dose-dependent decrements in timed memory task performance. However, the extract utilized in that study did not exhibit in vitro cholinergic receptor-binding properties. The current study involved an initial screening of samples of M. officinalis for human acetylcholinesterase inhibition and cholinergic receptor-binding properties. The cognitive and mood effects of single doses of the most cholinergically active dried leaf were then assessed in a randomized, placebo-controlled, double-blind, balanced crossover study. Following the in vitro analysis, 20 healthy, young participants received single doses of 600, 1000, and 1600 mg of encapsulated dried leaf, or a matching placebo, at 7-day intervals. Cognitive performance and mood were assessed predose and at 1, 3, and 6 h postdose using the Cognitive Drug Research computerized assessment battery and Bond-Lader visual analog scales, respectively. In vitro analysis of the chosen extract established IC(50) concentrations of 0.18 and 3.47 mg ml(-1), respectively, for the displacement of [(3)H]-(N)-nicotine and [(3)H]-(N)-scopolamine from nicotinic and muscarinic receptors in the human cerebral cortex tissue. However, no cholinesterase inhibitory properties were detected. The most notable cognitive and mood effects were improved memory performance and increased 'calmness' at all postdose time points for the highest (1600 mg) dose. However, while the profile of results was overwhelmingly favorable for the highest dose, decrements in the speed of timed memory task performance and on a rapid visual information-processing task increased with decreasing dose. These results suggest that doses of Melissa officinalis at or above the maximum employed here can improve cognitive performance and mood and may therefore be a valuable adjunct in the treatment of Alzheimer's disease. The results also suggest that different preparations derived from the same plant species may exhibit different properties depending on the process used for the sample preparation. (+info)
Inhibitory effects of rosmarinic acid extracts on porcine pancreatic amylase in vitro.
Porcine pancreatic alpha-amylase (PPA) was allowed to react with herbal extracts containing rosmarinic acid (RA) and purified RA. The derivatized enzyme-phytochemical mixtures obtained were characterized for residual amylase activity. These in vitro experiments showed that the amylase activity was inhibited in the presence of these phytochemicals. The extent of amylase inhibition correlated with increased concentration of RA. RA-containing oregano extracts yielded higher than expected amylase inhibition than similar amount of purified RA, suggesting that other phenolic compounds or phenolic synergies may contribute to additional amylase inhibitory activity. The significance of food-grade, plant-based amylase inhibitors for modulation of diabetes mellitus and other oxidation-linked diseases is hypothesized and discussed. (+info)
Variability in the content and composition of essential oil from lemon balm (Melissa officinalis L.) cultivated in Poland.
Essential oil from a few different population of M. officinalis cultivated in Poland has been investigated. The percentage of essential oil ranged from 0.08 to 0.25 ml/100 g in the leaves and from 0.06 to 0.167 ml/100 g in the herb and was higher in the plant material from experimental patch than that from commercial cultivations. Comparative determinations of the essential oil in fresh and dried material showed slightly higher content of the oil in the fresh one. The analysis of the oil composition has been performed by GC and GC/MS. Great differences in the contents of citral, citronellal, linalool, nerol, geraniol beta-caryophyllene and beta-caryophyllene oxide among the populations has been found. Effect of the harvest time, drying and storage on the composition of lemon balm oil has also been studied. (+info)
The effect of the Melissa officinalis extract on immune response in mice.
The effect of an extract from Melissa officinalis on immune response in mice was analysed using the cytotoxicity test in three dilutions (undiluted extract and extract diluted 10 and 100 times) and hemagglutination and rosette tests with various routes of administration (oral and subcutaneous). The immunostimulating activity of the extract was compared with that of a synthetic compound--levamisole, which influence on the immune system is well known. The present results confirm the effect of water extracts from leaves of Melissa on the immune system, in both humoral and cellular response. (+info)
Flavonoids and phenolic acids of Nepeta cataria L. var. citriodora (Becker) Balb. (Lamiaceae).
Luteolin 7-O-glucuronide, luteolin 7-O-glucurono-(1-->6)-glucoside, apigenin 7-O-glucuronide as well as free aglycones luteolin and apigenin have been isolated from lemon catnip herb (Nepeta cataria L. var citriodora). Luteolin 7-O-glucurono-(1-->6)-glucoside is probably a new compound, for the first time described. Two minor constituents of flavonoid fraction have been identified as apigenin 7-O-glucoside and luteolin 7-O-glucoside by means of HPLC method. The percentage of total flavonoids determined by use of spectrophotometric method was in the range from 0.30 to 0.46% of dry mass. In phenolic acid fraction, caffeic, rosmarinic and p-coumaric acids have been identified. Total amount of phenolic acids determined by spectrophotometric method was in the range of 0.75% to 1.4 % and the content of rosmarinic acid quantified by HPLC method fluctuated in the wide range from 0.06% to 0.15% depending on the sample. The results of the investigations showed that the composition of flavonoid compounds and phenolic acids in lemon catnip are similar to those in lemon balm (Melissa officinalis L.). The amount of flavonoids are similar in both plants, and the percentage of rosmarinic acid is about ten times lower in lemon catnip than in lemon balm. The presence of luteolin, apigenin and their glycosides, caffeic acid as well as the previously described terpenoids (ursolic acid, citral, nerol. geraniol) suggests the possibility of the use of lemon catnip herb as a constituent of phytopharmaceutical preparations with mild sedative, antispasmodic, antioxidative and antiinflammatory action. (+info)
Comparison of rosmarinic acid content in commercial tinctures produced from fresh and dried lemon balm (Melissa officinalis).
PURPOSE: To measure the rosmarinic acid content of eight commercial tinctures derived from fresh (n= 5) and dried (n=3) Melissa officinalis herb. METHODS: Rosmarinic acid and the internal standard (esculin) were purchased from Aldrich Chemical Co. The column used was a Luna C18, 5 um (150 x 4.6 mm I.D., Phenomenex) maintained at ambient room temperature. The HPLC system consisted of a Shimadzu SCL-6B controller, Shimadzu LC-6A pumps, Shimadzu SPD-6A UV single wavelength spectrophotometric detector set to 320 nm and Shimadzu SIL-6B autosampler. Gradient elution of the samples and standard were performed using ammonium formate (0.02 M; pH 6.25 at 27 oC; eluent A) and methanol (eluent B). The gradient elution initial conditions were 2% of eluent B with linear gradient to 60% at 30 min, followed by linear gradient to 90% of eluent B at 31 min, this proportion being maintained for 4 min. The column was then returned to the initial condition at 36 min and maintained until the end of the run at 43 min. The flow rate was 1 mL/min. The assay was validated for sensitivity, accuracy and reproducibility. RESULTS: The content of rosmarinic acid in commercial tinctures was significantly higher in the tinctures made from dried plant material (2.96 - 22.18 mg/mL) compared to fresh plant tinctures (+info)