Melastoma malabathricum (MM) is a well-known plant in Malaysian traditional medicine, locally known as senduduk. Its ethanol and aqueous extracts have been used in the present investigation to study the immunomodulatory role on human peripheral blood mononuclear cell (PBMC), and the DPPH, ABTS and FRAP free radical scavenging activities were also measured. Total flavonoids and total phenolic contents were assayed and the antibacterial effect was tested against four species of bacteria; two Gram-positive (Staphylococcus aureus and Streptococcus agalactiae) and two Gram-negative (Escherichia coli and Klebsilla pneumonia). The tests were carried out using the disc diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) methods. Moreover, the acute toxicity was evaluated in vivo on the ethanol extract of MM to establish its safety when administered orally. In our results, both extracts of MM showed abilities to scavenge DPPH and ABTS free radicals, IC(50) values: (11.599 ± 0.84, 10.573 ± 0.58 µmol/L) and (62.657 ± 0.78, 63.939 ± 0.48 µmol/L) for ethanol and aqueous extracts respectively. Indeed the ethanol extract evidenced high phenolic content (384.33 ± 0.005 mg/g), flavonoids contents (85.8 ± 0.009 mg/g) and ferric reducing antioxidant power (33,590 ± 0.038 mmol/g), with high activity against S. aureus and S. agalactiae (11 ± 0.3 and 12 ± 0.6 mm inhibition zones). Likewise, the percentage of peripheral blood mononuclear cells (PBMC) viability was increased in response to MM, IC(50) values (1.781 ± 1.2 and 6.545 ± 0.93 µg/mL) for ethanol and aqueous extracts, respectively. In addition, our results showed that the MM extract is safe even at a high dose of 5,000 mg/kg and has no oral toxicity. These findings suggest the excellent medicinal bioactivity of MM and explain the popularity of this plant in the folk medicine as a remedy for different illnesses.
In the Indian system of traditional medicine (Ayurveda) it is recommended to consume Ipomoea aquatica to mitigate disorders like jaundice. In this study, the protective effects of ethanol extract of I. aquatica against liver damage were evaluated in thioacetamide (TAA)-induced chronic hepatotoxicity in rats. There was no sign of toxicity in the acute toxicity study, in which Sprague-Dawley (SD) rats were orally fed with I. aquatica (250 and 500 mg/kg) for two months along with administration of TAA (i.p injection 200 mg/kg three times a week for two months). The results showed that the treatment of I. aquatica significantly lowered the TAA-induced serum levels of hepatic enzyme markers (ALP, ALT, AST, protein, albumin, bilirubin and prothrombin time). The hepatic content of activities and expressions SOD and CAT that were reduced by TAA were brought back to control levels by the plant extract supplement. Meanwhile, the rise in MDA level in the TAA receiving groups also were significantly reduced by I. aquatica treatment. Histopathology of hepatic tissues by H&E and Masson trichrome stains displayed that I. aquatica has reduced the incidence of liver lesions, including hepatic cells cloudy swelling, infiltration, hepatic necrosis, and fibrous connective tissue proliferation induced by TAA in rats. Therefore, the results of this study show that the protective effect of I. aquatica in TAA-induced liver damage might be contributed to its modulation on detoxification enzymes and its antioxidant and free radical scavenger effects. Moreover, it confirms a scientific basis for the traditional use of I. aquatica for the treatment of liver disorders.
A new indole alkaloid, naucline (1) together with four known alkaloids, angustine (2), angustidine (3), nauclefine (4) and naucletine (5), were isolated from the bark of Nauclea officinalis. The structures of all isolated compounds were elucidated with various spectroscopic methods such as 1D- and 2D- NMR, IR, UV and LCMS-IT-TOF. In addition to that of alkaloid 1, the complete 13C-NMR data of naucletine (5) were also reported. Naucline (1) showed a moderate vasorelaxant activity (90% relaxation at 1 × 10(-5) M) whereas, angustine (2), nauclefine (4), and naucletine (5) showed potent vasorelaxant activity (more than 90% relaxation at 1 × 10(-5) M) on an isolated rat aorta.
A phytochemical study of the bark of Alseodaphne perakensis has yielded three aporphine alkaloids: the new compound N-cyanomethylnorboldine (1), and the two known alkaloids N-methyllaurotetanine (2) and norboldine (3). The isolation was achieved by chromatographic techniques and the structural elucidation was performed via spectral methods, notably 1D- and 2D-NMR, UV, IR, and HRFABMS. The vasorelaxation activity of compound 1 has been studied.
In the present study we investigated the effects of panduratin A, isolated from Boesenbergia rotunda, on proliferation and apoptosis in A549 human non-small cell lung cancer cells. Cell proliferation and induction of apoptosis was determined by the real-time cellular analyzer (RTCA), MTT assay and High Content Screening (HCS). The RTCA assay indicated that panduratin A exhibited cytotoxicity, with an IC₅₀ value of 4.4 µg/mL (10.8 µM). Panduratin A arrested cancer cells labeled with bromodeoxyuridine (BrdU) and phospho-Histone H3 in the mitotic phase. The cytotoxic effects of panduratin A were found to be accompanied by a dose-dependent induction of apoptosis, as assessed by DNA condensation, nuclear morphology and intensity, cell permeability, mitochondrial mass/ potential, F-actin and cytochrome c. In addition, treatment with an apoptosis-inducing concentration of panduratin A resulted in significant inhibition of Nuclear Factor-kappa Beta (NF-κB) translocation from cytoplasm to nuclei activated by tumor necrosis factor-alpha (TNF-α), as illustrated by the HCS assay. Our study provides evidence for cell growth inhibition and induction of apoptosis by panduratin A in the A549 cell line, suggesting its therapeutic potential as an NF-κB inhibitor.
Phytochemical investigation of Beilschmiedia alloiophylla has resulted in the isolation of one new alkaloid, 2-hydroxy-9-methoxyaporphine (1), and ten known natural products, laurotetanine (2), liriodenine (3), boldine (4), secoboldine (5), isoboldine (6), asimilobine (7), oreobeiline (8), 6-epioreobeiline (9), β-amyrone (10), and (S)-3-methoxynordomesticine (11). Chemical studies on the bark of B. kunstleri afforded compounds 2 and 4 along with one bisbenzylisoquinoline alkaloid, N-dimethylphyllocryptine (12). Structures of compounds 1-12 were elucidated on the basis of spectroscopic methods. All of these isolates were evaluated for their anti-acetylcholinesterase (AChE), anti-α-glucosidase, anti-leishmanial and anti-fungal activities. Compounds 1-12 exhibited strong to moderate bioactivities in aforementioned bioassays.
Generation of reactive oxygen species plays a pivotal role in the development of cardiovascular diseases. The present study describes the effects of the methanolic extract of Phoebe grandis (MPG) stem bark on reactive oxygen species-induced endothelial dysfunction in vitro. Endothelium-dependent (acetylcholine, ACh) and -independent relaxation (sodium nitroprusside, SNP) was investigated from isolated rat aorta of Sprague-Dawley (SD) in the presence of the β-NADH (enzymatic superoxide inducer) and MPG extract. Superoxide anion production in aortic vessels was measured by lucigen chemiluminesence. Thirty minutes incubation of the rat aorta in vitro with β-NADH increased superoxide radical production and significantly inhibited ACh-induced relaxations. Pretreatment with MPG (0.5, 5 and 50 μg/mL) restored the ACh-induced relaxations (R(max): 92.29% ± 2.93, 91.02% ± 4.54 and 88.31 ± 2.36, respectively) in the presence of β-NADH. MPG was ineffective in reversing the impaired ACh-induced relaxations caused by pyrogallol, a non-enzymatic superoxide generator. Superoxide dismutase (a superoxide scavenger), however, reversed the impaired ACh relaxations induced by both β-NADH and pyrogallol. MPG also markedly inhibited the β-NADH-induced generation of the superoxide radicals. Furthermore, MPG scavenging peroxyl radicals generated by tBuOOH (10⁻⁴ M).These results indicate that MPG may improve the endothelium dependent relaxations to ACh through its scavenging activity as well as by inhibiting the NADH/NADPH oxidase induced generation of superoxide anions.
The teaching profession is an occupation at high risk for stress. This research attempted to determine the prevalence of stress and the associated factors contributing to stress among teachers in Malaysia. A cross-sectional study was conducted on 580 secondary school teachers in Kota Bharu District. The instrument used to carry out the study was adopted and modified from the Depression, Anxiety and Stress Scale (DASS 21) and Job Content Questionnaire (JCQ). The questionnaire consisted of two parts: Part I consisting non-job factors (socio-demographic characteristics) and Part II consisting of psychosocial factors contributing to stress. Simple and multiple linear regression analysis were carried out. The prevalence of stress was reported as 34.0%. Seventeen point four percent of teachers experienced mild stress. Age, duration of work and psychological job demands were significantly associated with stress level. This study indicates job-related factors did not contribute much to stress among secondary school teachers. Non-job-related factors should be further studied to determine methods for stress reduction in teachers in Malaysia.
The title compound, systematic name 9-isopropyl-idene-2,6-dimethyl-11-oxatricyclo-[6.2.1.0(1,5)]undec-6-en-8-ol, C(15)H(22)O(2), which crystallizes with two mol-ecules of similar conformation in the asymmetric unit, features three fused rings, two of which are five-membered and the third six-membered. Of the two five-membered rings, the one with an O atom has a distinct envelope shape (with the O atom representing the flap). The six-membered ring is also envelope-shaped as it shares a common O atom with the five-membered ring. In the crystal, the two independent mol-ecules are linked by a pair of O-H⋯O hydrogen bonds, generating a dimer.
Dunaliine A (1), a new amino diketone, has been isolated from the leaves of Desmos dunalii together with four known dihydrochalcones: 2',4-dihydroxy-4',6'-dimethoxy-3',5'-dimethyldihydrochalcone (2), 2',4-dihydroxy-4',6'-dimethoxydihydrochalcone (3), 2',4-dihydroxy-4',5',6'-trimethoxydihydrochalcone (4) and 2',4-dihydroxy-5'-methyl-4',6'-dimethoxydihydrochalcone (5). The structures of these compounds were established notably by spectral analysis (1D- and 2D- (1)H, (13)C NMR), UV, IR and HRMS.
The stem bark of Phoebe grandis afforded one new oxoproaporphine; (-)-grandine A (1), along with six known isoquinoline alkaloids: (-)-8,9-dihydrolinearisine (2), boldine, norboldine, lauformine, scortechiniine A and scortechiniine B. In addition to that of the new compound, complete 1H- and 13C-NMR data of the tetrahydroproaporphine (-)-8,9-dihydrolinearisine (2) is also reported. The alkaloids' structures were elucidated primarily by means of high field 1D- and 2D-NMR and HRMS spectral data.
A new bisindole alkaloid, bisnicalaterine A (1), consisting of two vobasine-type skeletons, and 3-epivobasinol (2) and 3-O-methylepivobasinol (3), with vobasine-type skeletons, were isolated from the leaves of Hunteria zeylanica, and their structures were elucidated on the basis of spectroscopic data and chemical correlation. Bisnicalaterine A showed moderate cytotoxicity against various human cancer cell lines.
The mol-ecule of accanthomine A, C(15)H(13)N(5), is approximately planar, with the indolyl fused-ring and the pyrimidyl ring being twisted by 31.7 (1)° The amino group of the five-membered ring is an intramolecular hydrogen-bond donor to a nitro-gen acceptor of the pyrimide ring. The amino group of the pyrimide ring is a hydrogen-bond donor to the N atoms of adjacent mol-ecules. These hydrogen-bonding inter-actions give rise to a layered network with a 4.8(2) topology.
The bark of Cryptocarya crassinervia provided two new phenantrene alkaloids, 2-hydroxyatherosperminine (1) and N-demethyl-2-methoxyatherosperminine (2).
The phytochemical study of the bark of Malaysian Phoebe scortechinii (Lauraceae) has resulted in the isolation and identification of two new proaporphine alkaloids; (+)-scortechiniine A (1) and (+)-scortechiniine B (2) together with two known proaporphines; (-)-hexahydromecambrine A (3), (-)-norhexahydromecambrine A (4), and one aporphine; norboldine (5). Structural elucidations of these alkaloids were performed using spectroscopic methods especially 1D and 2D (1)H and (13)C NMR.
The leaves of the Phoebe scortechinii (Gamb.) Kochummen Comb. Nov. (Lauraceae), afforded one new proaporphine-tryptamine dimer; (-)-phoebescortechiniine (1), along with two known ones; phoebegrandine A and phoebegrandine B. The proaporphine, tetrahydropronuciferine (2), was isolated for the first time as a natural product. The alkaloids were elucidated primarily by means of high field NMR and HRMS.
Five new cytotoxic limonoids, erythrocarpines A-E (1-5), were isolated from the bark of Chisocheton erythrocarpus Hiern. Chemical structures, stereochemistry, and conformation were fully elucidated and characterized by 2D NMR, MS, and computational methods.
The hydr-oxy groups in the title compound, C(16)H(14)O(4), are each hydrogen bonded to the adjacent meth-oxy O atom; one of the two hydr-oxy groups is additionally linked to the O atom of the meth-oxy group of another mol-ecule, forming a linear chain.
The alkaloidal extract of the leaves of Phoebe grandis (nees) merr. have provided two new minor alkaloids; phoebegrandine D (1), a proaporphine-tryptamine dimer, and phoebegrandine E (2), an indoloquinolizidine. This is the first report on the occurrence of an indoloquinolizidine in the Phoebe species. The crude extract also exhibited antiplasmodial activity (IC50<8 microg mL-1). The structures of the novel compounds were elucidated by spectroscopic methods, notably 2D NMR and HRMS.