GABase and glutaminase inhibitory activities of herbal extracts and acylated flavonol monoglycosides isolated from the leaves of Laurus nobilis L.

This study was to compare GABase [a mixture of γ-aminobutyric acid (GABA) aminotransferase and succinic semialdehyde dehydrogenase] and glutaminase inhibitory activities of 20 herbal extracts and investigate the isolation, structural elucidation and those inhibitory activities of three acylated flavonol monoglycosides from the selected extract of Laurus nobilis L. (laurel). On the basis of the NMR spectroscopic data and the ESI MS spectra together with the comparison with the literature values, three compounds were identified as kaempferol-3-O-(4″-E-p-coumaroyl)-α-l-rhamnopyranoside (1), kaempferol-3-O-(3″,4″-di-E-p-coumaroyl)-α-l-rhamnopyranoside (2) and kaempferol-3-O-(2″,4″-di-E-p-coumaroyl)-α-l-rhamnopyranoside (3), respectively. The IC50 values of GABase inhibitory activity of 1-3 and p-hydroxybenzaldehyde (HBA) as control were 0.24 mM, 0.14 mM, 0.12 mM and 0.43 mM, respectively. Additionally, the IC50 values of glutaminase inhibitory activity of 1-3 and 6-diazo-5-oxo-l-norleucine (DON) as control were 0.34 mM, 0.13 mM, 0.14 mM and 0.33 mM, respectively. The results suggest that the extract from laurel shows the strongest biological activities among 20 herbal extracts and three acylated flavonol monoglycosides may serve as potential lead compounds for the prevention and treatment of neurodegenerative and lifestyle-related diseases by targeting GABase and glutaminase. This is the first report on GABase and glutaminase inhibitory activities of 1-3.

Glutaminase inhibitory activity of umbelliferone isolated from kabosu (Citrus sphaerocarpa Hort. ex Tanaka).

Kabosu (Citrus sphaerocarpa Hort. ex Tanaka) fruits have pleasant and fresh odors and have been used as raw materials for vinegar, seasonings, jams, marmalades and juices in Japan. The n-butanol extracts from kabosu fruits were prepared and a component in the extract was purified by column chromatography and HPLC to afford compounds 1-3. Three compounds, 5-(hydroxymethyl)-2-furaldehyde (1), umbelliferone (2) and oxypeucedanin hydrate (3), have been isolated from kabosu, and the structures of compounds 1-3 were elucidated by 1 D and 2 D NMR as well as EI-MS. Compound 2 exhibited potent glutaminase inhibitory activity with an IC50 value of 1.33 mM. This is the first report on glutaminase inhibitory activity of 2 and the isolation of three compounds 1-3 from kabosu fruits.

Comparative studies of the biological activities of selected herbal extracts and phenolic compounds isolated from Rosa gallica.

This study aimed to compare the biological activities of 35 herbal hydroethanolic extracts and select high potential extract, which showed antioxidative activity and inhibitory activities of α-glucosidase, lipase, and hyaluronidase, and to investigate the isolation, structural elucidation, and biological activities of five phenolic compounds from the selected extracts of Rosa gallica. On the basis of one-dimensional nuclear magnetic resonance together with the comparison with the literature values, the phenolic compounds were identified as methyl gallate (1), kaempferol-3-O-arabinofuranoside (2), multinoside A acetate (3), kaempferol (4), and quercetin (5), respectively. The results suggest that the extracts from R. gallica show the strongest biological activities in 35 herbal extracts and that 1, 4, and 5 among the five isolated compounds from rose extracts are effective in promoting antioxidative and enzymatic inhibitory activities.

Attenuation Effects of Alpha-Pinene Inhalation on Mice with Dizocilpine-Induced Psychiatric-Like Behaviour.

α-Pinene, an organic terpene compound found in coniferous trees, is used as a safe food additive and is contained in many essential oils. Moreover, some studies have shown that α-pinene suppresses neuronal activity. In this study, we investigated whether inhalation of α-pinene suppresses dizocilpine (MK-801-) induced schizophrenia-like behavioural abnormalities in mice. Mice inhaled α-pinene 1 h before the first MK-801 injection. Thirty minutes after MK-801 injection, the open field, spontaneous locomotor activity, elevated plus maze, Y-maze, tail suspension, hot plate, and grip strength tests were conducted as behavioural experiments. Inhalation of α-pinene suppressed the activity of mice in the spontaneous locomotor activity test and although it did not suppress the MK-801-induced increased locomotor activity in the open field test, it remarkably decreased the time that the mice remained in the central area. Inhalation of α-pinene suppressed the MK-801-induced increased total distance travelled in the Y-maze test, whereas it did not alter the MK-801-induced reduced threshold of antinociception in the hot plate test. In the tail suspension and grip strength tests, there was no effect on mouse behaviour by administration of MK-801 and inhalation of α-pinene. These results suggest that α-pinene acts to reduce MK-801-induced behavioural abnormalities resembling those seen in neuropsychiatric disorders. Therefore, both medicinal plants and essential oils containing α-pinene may have potential for therapeutic treatment of schizophrenia.

Anti-stress effects of the hydroalcoholic extract of Rosa gallica officinalis in mice.

Rosa gallica, a plant of the Rosa genus, has been used widely since the 13th century and is cultivated in many areas as a medicinal plant for the preparation of herbal medicines. However, details of the neuropsychological effects of R. gallica remain unclear; therefore we aimed to investigate the neuropsychological effects of a water-soluble extract of R. gallica in male C57BL/6N mice under normal conditions and under chronic stress. We administered a water-soluble extract of R. gallica to mice and performed a series of behavioral experiments to compare the treated animals with the untreated controls. No significant differences in activity level, anxiety-like behavior, depression-like behavior, body weight, and body temperature were observed between R. gallica-treated mice and control mice. However, in mice subjected to chronic stress, the observed decrease in activity was smaller in the R. gallica-treated mice than in the control mice. The oral administration of R. gallica did not affect the normal behavior of mice. However, when the mice were subjected to stress, R. gallica exerted an anti-stress effect. Therefore, R. gallica has potential as a medicinal plant for the purpose of stress prevention.

Anti-depressive-like effect of 2-phenylethanol inhalation in mice.

Rose oil has traditionally been used to treat psychiatric disorders, but the scientific basis of this treatment remains poorly understood. The main odor component of rose oil is 2-phenylethanol (2-PE), but the neuropsychological effects of 2-PE have not been investigated in detail. Thus, we aimed to investigate the effects of 2-PE on mouse behavior. We first investigated whether 2-PE is attractive or repulsive to mice. After 2-PE inhalation, the mice underwent a series of behavioral experiments, such as the elevated plus maze, open field, Y-maze, tail-suspension, and Porsolt forced-swim tests. Mice did not have a strong interest in 2-PE but were not repelled by it nor were fearful. In the open field test, mice that had inhaled 2-PE spent less time in the center area, while in the tail suspension test, their immobility time decreased. There was no change in cognitive function, activity level, muscle strength, or aggression in these mice. Our results suggest that 2-PE elicits neuropsychological effects that alter the behavior of mice and may also elicit anti-depressive effects. Inhalation of rose oil containing 2-PE may be effective against depression and stress-related diseases.

Caffeic Acid Derivatives from Bacopa monniera Plants as Inhibitors of Pancreatic Lipase Activity and their Structural Requirements.

The methanol extract of whole Bacopa monniera plants inhibited pancreatic lipase activity in vitro. From this extract we have reported the isolation of 11 triterpene glycosides and 5 phenylethanoid- and/or phenylpropanoid- glycosides. In this paper, we describe the effects of the methanol extract and/or its constituents on pancreatic lipase activity and the isolation of an active constituent, desrhamnosyl isoacteoside. In addition, the structural requirements for its inhibitory effects were examined. We also examined the effects on the elevation of plasma triglyceride (TG) levels in olive oil loaded mice. The major active constituents, desrhamnosyl isoacteoside and plantainoside B, reduced plasma TG levels in the mice. The inhibitory effects of B. monniera and its constituents on pancreatic lipase activity and plasma TG level are reported for the first time.

Interaction between aspterric acid and indole-3-acetic acid on reproductive growth in Arabidopsis thaliana.

Application of indole-3-acetic acid (IAA) with a pollen growth inhibitor, aspterric acid (AA), results in the recovery of normal pollen development. In contrast, application of gibberellin (GA3) with AA do not induce normal pollen growth. In addition, application of different concentrations of IAA with AA shortens the period of growth from bolting to first flowering as compared to that treated with AA alone. Furthermore, stem length and number of flower bud treated with IAA and AA were similar to those of control. These results suggest, that IAA may play an important role in reproductive growth of A. thaliana.

Penipratynolene, a novel nematicide from penicillium bilaiae Chalabuda.

New acetylenic nematicidal compound, penipratynolene (1), methy (2'R)-4-(2'-hydroxy-3'-butynoxy)benzoate, together with two known compounds, 6-methoxycarbonylpicolinic acid (2) and 2,6-pyridinedicarboxylic acid (3), were isolated from the culture filtrate of Penicillium bilaiae Chalabuda. The structures of 1-3 were established by spectroscopic methods. The absolute configuration of 1 was confirmed by using a modified version of Mosher's method. Compounds 1-3 showed nematicidal activity of 77%, 52%, and 98%, respectively, by a bioassay at 300 mg/l with the root-lesion nematode Pratylenchus penetrans.

Hydroxysulochrin, a tea pollen growth inhibitor from the fungus Aureobasidium sp.

A new plant growth regulator, hydroxysulochrin (1), together with sulochrin (2) was isolated from the culture filtrate of Aureobasidium sp. grown on a malt extract medium. The structures of 1 and 2 were established by spectroscopic methods. 1 and 2 inhibited tea pollen tube growth by 41% and 36% of the control value at a concentration of 100 mg/l, respectively. However, 1 and 2 showed no inhibitory effect on the growth of lettuce seedlings from 0.1 mg/l to 100 mg/l.

Aspterric acid and 6-hydroxymellein, inhibitors of pollen development in Arabidopsis thaliana, produced by Aspergillus terreus.

Aspterric Acid, 6-Hydroxymellein, Arabidopsis thaliana, Aspergillus terreus Aspterric acid (1) and 6-hydroxymellein (2), inhibitors of pollen development in Arabidopsis thaliana, have been isolated from the fungus Aspergillus terreus. 1 and 2 inhibited the pollen development at concentrations of 38 and 52 microM, respectively. The microscopic examination of pollen development suggested that the inhibition by the treatment with 1 caused at meiosis and the inhibition by the treatment with 2 caused at microspore stage. 1 and 2 could be useful agents for the molecular investigation of anther and pollen development in higher plants.

Myxostiolide, myxostiol, and clavatoic acid, plant growth regulators from the fungus Myxotrichum stipitatum.

New plant growth regulators, named myxostiolide (1), myxostiol (2), and clavatoic acid (3), have been isolated from Myxotrichum stipitatum, and their structures have been established by spectroscopic methods including 2D NMR. The biological activities of 1, 2, and 3 have been examined using tea pollen and lettuce seedling bioassay methods. With tea pollen, compound 1 inhibited the pollen tube growth to 14% of control at a concentration of 100 mg/L. With lettuce seedlings, compound 2 accelerated the root growth from 1 mg/L to 100 mg/L and compound 3 inhibited the root growth, to 52% of control, at a concentration of 100 mg/L.