In medium containing theanine with glutaminase in vitro, glutamate gradually generated, showing that glutaminase reacted with theanine. Furthermore, the generation of glutamate increased by reaction of theanine and gamma-glutamyltranspeptidase (gamma-GTP), showed that gamma-GTP converted theanine to glutamate. It is expected that theanine metabolism occurred by hydrolysis and rearrangement reaction by gamma-GTP in the liver. Namely, it is suggested that the metabolism of theanine mediated by glutaminase and gamma-GTP and the increase of glutamate mediated GSH is important for theanine-induced action.
The aim of this study was to compare 50 mg caffeine, with and without 100 mg L-theanine, on cognition and mood in healthy volunteers. The effects of these treatments on word recognition, rapid visual information processing, critical flicker fusion threshold, attention switching and mood were compared to placebo in 27 participants. Performance was measured at baseline and again 60 min and 90 min after each treatment (separated by a 7-day washout). Caffeine improved subjective alertness at 60 min and accuracy on the attention-switching task at 90 min. The L-theanine and caffeine combination improved both speed and accuracy of performance of the attention-switching task at 60 min, and reduced susceptibility to distracting information in the memory task at both 60 min and 90 min. These results replicate previous evidence which suggests that L-theanine and caffeine in combination are beneficial for improving performance on cognitively demanding tasks.
A combination of green tea extract and l-theanine (LGNC-07) has been reported to have beneficial effects on cognition in animal studies. In this randomized, double-blind, placebo-controlled study, the effect of LGNC-07 on memory and attention in subjects with mild cognitive impairment (MCI) was investigated. Ninety-one MCI subjects whose Mini Mental State Examination-K (MMSE-K) scores were between 21 and 26 and who were in either stage 2 or 3 on the Global Deterioration Scale were enrolled in this study. The treatment group (13 men, 32 women; 57.58 +/- 9.45 years) took 1,680 mg of LGNC-07, and the placebo group (12 men, 34 women; 56.28 +/- 9.92 years) received an equivalent amount of maltodextrin and lactose for 16 weeks. Neuropsychological tests (Rey-Kim memory test and Stroop color-word test) and electroencephalography were conducted to evaluate the effect of LGNC-07 on memory and attention. Further analyses were stratified by baseline severity to evaluate treatment response on the degree of impairment (MMSE-K 21-23 and 24-26). LGNC-07 led to improvements in memory by marginally increasing delayed recognition in the Rey-Kim memory test (P=0 .0572). Stratified analyses showed that LGNC-07 improved memory and selective attention by significantly increasing the Rey-Kim memory quotient and word reading in the subjects with MMSE-K scores of 21-23 (LGNC-07, n=11; placebo, n=9). Electroencephalograms were recorded in 24 randomly selected subjects hourly for 3 hours in eye-open, eye-closed, and reading states after a single dose of LGNC-07 (LGNC-07, n=12; placebo, n=12). Brain theta waves, an indicator of cognitive alertness, were increased significantly in the temporal, frontal, parietal, and occipital areas after 3 hours in the eye-open and reading states. Therefore, this study suggests that LGNC-07 has potential as an intervention for cognitive improvement.
Recent neuropharmacological research has suggested that certain constituents of tea may have modulatory effects on brain state. The bulk of this research has focused on either L-theanine or caffeine ingested alone (mostly the latter) and has been limited to behavioral testing, subjective rating, or neurophysiological assessments during resting. Here, we investigated the effects of both L-theanine and caffeine, ingested separately or together, on behavioral and electrophysiological indices of tonic (background) and phasic (event-related) visuospatial attentional deployment. Subjects underwent 4 d of testing, ingesting either placebo, 100 mg of L-theanine, 50 mg of caffeine, or these treatments combined. The task involved cued shifts of attention to the left or right visual hemifield in anticipation of an imperative stimulus requiring discrimination. In addition to behavioral measures, we examined overall, tonic attentional focus as well as phasic, cue-dependent anticipatory attentional biasing, as indexed by scalp-recorded alpha-band (8-14 Hz) activity. We found an increase in hit rate and target discriminability (d') for the combined treatment relative to placebo, and an increase in d' but not hit rate for caffeine alone, whereas no effects were detected for L-theanine alone. Electrophysiological results did not show increased differential biasing in phasic alpha across hemifields but showed lower overall tonic alpha power in the combined treatment, similar to previous findings at a larger dosage of L-theanine alone. This may signify a more generalized tonic deployment of attentional resources to the visual modality and may underlie the facilitated behavioral performance on the combined ingestion of these 2 major constituents of tea.
This review summarizes the literature on the association between two dietary components of tea, caffeine and L-theanine, and the psychological outcomes of consumption; it also identifies areas for future research. The studies reviewed suggest that caffeinated tea, when ingested at regular intervals, may maintain alertness, focused attention, and accuracy and may modulate the more acute effects of higher doses of caffeine. These findings concur with the neurochemical effects of L-theanine on the brain. L-theanine may interact with caffeine to enhance performance in terms of attention switching and the ability to ignore distraction; this is likely to be reflective of higher-level cognitive activity and may be sensitive to the detrimental effects of overstimulation. Further research should investigate the interactive effects of caffeine, L-theanine, and task complexity, utilize a range of ecologically valid psychological outcomes, and assess the neuroprotective effects of L-theanine using epidemiological or longer-term intervention studies among individuals at risk of neurodegenerative disease.
/SRP:/ Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Poisons A and B/
From animal studies, it appears that L-theanine is absorbed from the small intestine via a sodium-coupled active transport process and appears to cross the blood-brain barrier. It has been found in the rat studies that the D-enantiomer of theanine may decrease the absorption of L-theanine.
[EN] LEVORPHANOL PRODRUGS AND PROCESSES FOR MAKING AND USING THEM<br/>[FR] PROMÉDICAMENTS DE LEVORANOL ET LEURS PROCÉDÉS DE FABRICATION ET D'UTILISATION
申请人：KEMPHARM INC
公开号：WO2018191472A1
公开（公告）日：2018-10-18
The presently described technology provides compositions of one or more of oxoacids, polyethylene glycols, and vitamin compounds chemically conjugated to levorphanol ((-)-17-methylmorphinan-3-ol) to form novel prodrugs and compositions of levorphanol.
[EN] AMINO ACID DERIVATIVES AND THEIR USE AS FLAVOR MODIFIERS<br/>[FR] DÉRIVÉS D'ACIDES AMINÉS ET LEUR UTILISATION EN TANT QUE MODIFICATEURS DE GOÛT
申请人：FIRMENICH & CIE
公开号：WO2021209345A1
公开（公告）日：2021-10-21
The present invention provides derivatives of glutamine of formula (I) and derivatives of arginine of formula (II), and the use of such compounds as flavor modifiers. The invention further provides the use of such derivatives of glutamine and arginine to enhance the salty and umami taste of ingestible compositions as ingestible compositions that include such derivatives of glutamine and arginine and bulking agents.
γ-Glutamyl Transfer Reactions by Glutaminase from<i>Pseudomonas nitroreducens</i>IFO 12694 and Their Application for the Syntheses of Theanine and γ-Glutamylmethylamide
In a mixture containing γ-glutamyl donor (donor) and γ-glutamyl acceptor (acceptor), the glutaminase of Pseudomonas nitroreducens IFO 12694 simultaneously catalyzed a γ-glutamyl transfer reaction and hydrolysis of the donor. The variation of the activities responding to the concentration of glutathione and glycylglycine indicated that the enzyme might be classified in a group of glutaminases that shows hydrolysis prior to transfer reaction. On the other hand, the results with glutamine and ethylamine or methylamine indicated that the enzyme was active in the transfer reaction with suppressed hydrolysis of glutamine, and suggested the possibility of using the reaction for producing γ-glutamylethylamide (theanine) or γ-glutamylmethylamide (γ-GMA). In fact, in a mixture containing high concentrations of substrates (0.7 M glutamine, 1.5 M ethylamine or methylamine) and 0.5 unit/ml glutaminase (borate buffer pH 11), 270 mM (47 g/L) theanine or 250 mM (38 g/L) γ-GMA was formed in 7 h of incubation at 30°C.
γ-Glutamyltranspeptidase from Pseudomonas nitroreducens IFO12694 (PnGGT) exhibited higher hydrolytic activity than transfer activity, as compared with other γ-glutamyltranspeptidases (GGTs). PnGGT showed little activity towards most of l-amino acids and towards glycyl-glycine, which is often used as a standard γ-glutamyl accepter in GGT transfer reactions. The preferred substrates for PnGGT as a γ-glutamyl accepter were amines such as methylamine, ethylamine, and isopropylamine.
FLAVOR MODULATOR HAVING PYRIDINE DERIVATIVE OR SALT THEREOF AS ACTIVE INGREDIENT
申请人：T. HASEGAWA CO., LTD.
公开号：US20180072670A1
公开（公告）日：2018-03-15
2-(phenylalkyloxyalkyl)pyridine derivative or a 2-(phenylalkylthioalkyl)pyridine derivative imparts, when added to food and drink or cosmetics as an active ingredient, a flavor of natural impression thereto; and in particular, when added to food and drink, the compound imparts an umami imparting or enhancing, a saltiness enhancing a sweetness enhancing, and in particular, when added to a milk or dairy product, a food or drink product containing a milk or dairy product, or a dairy replacement product, the compound provides a milk richness enhancing.
