Flavonoids and triterpenes from the leaves of artocarpus fulvicortex

Five flavonoids, 5-hydroxy-(6:7,3:4)-di(2,2- dimethylpyrano)flavone 1, carpachromene 2, cycloartocarpesin 3, norartocarpetin 4 and 2′-hydroxy-4,4′,6′- trimethoxychalcone 5, along with three triterpenes, friedelin 6, lupeol 7 and β-sitosterol 8 were isolated for the first time from the leaves of Artocarpus fulvicortex F.M. Jarrett. The structures of these compounds were established by analysis of their spectroscopic (1D and 2D NMR) and spectrometric (MS) data, as well as by comparison of these with those reported in the literature

Phytochemistry and antioxidant activity of garcinia prainiana

Phytochemical investigation of the leaves and stem bark of G. prainiana was carried out. The leaves and stem barks of G. prainiana collected from Kuantan, Pahang were extracted by soxhletextractorwith hexane, dichloromethane and methanol to get the crude exkacts. The crude extracts were purified by column chromatography io yield pure compounds which were characterized spectroscopically using lR, NMR (1D and 2D), UV and MS. Fractionation and purification of the hexane extract of leaves yielded triterpenes, squalene and friedelin. The methanol extract of leaves and stem barks afforded bioflavonoid characterized as morelloflavone and O-methyl fukugetin. Total phenolic content studies were carried out on the crude extracts by using Folin-Ciocalteau reagent. The methanol extract of leaves and stem barks showed the highest total phenolic content expressed as gallic acid and (t)-catechin equivalents. These extracts also showed the highest value of ascorbic acid and butylated hydroxytoluene (BHT) equivalents on forming the phosphomolybdenum complex in the total antioxidant assay. The antioxidant assay on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical showed that the methanolextract of stem barks had the highest free radical scavenging activity with lCso value 74.5trr9/ml while the isolated compound, morelloflavone revealed a strong free radical scavenging activity with lCsovalue 15.7p9/m

Tyrosinase inhibition, anti-acetylcholinesterase, and antimicrobial activities of the phytochemicals from Gynotroches axillaris Blum

The leaves of Gynotroches axillaris were chemically and biologically studied. Sequential extraction of the leaves using petroleum ether, chloroform, and methanol afforded three extracts. Purification of pet. ether extract yielded, squalene and β-amyrin palmitate as the major compounds, together with palmitic acid and myristic acid as the minor components. The methanol extract yielded two flavonoids, quercitrin and epicatechin. The isolated compounds were characterized by MS, IR and NMR (1D and 2D). Anti-acetyl cholinesterase screening using TLC bio-autography assay showed that palmitic acid and myristic acid were the strongest inhibition with detection limit 1.14 and 1.28 µg/ 5 µL respectively. Antibacterial against Gram-positive and negative and antifungal activities exhibited that β-amyrin palmitate was the strongest (450-225 μg/mL) against all the tested microbes. The tyrosinase inhibition assay of extracts and the pure compounds were screened against tyrosinase enzyme. The inhibition percentage (I%) of methanol extract against tyrosinase enzyme was stronger than the other extracts with value 68.4%. Quercitrin (59%) was found to be the highest in the tyrosinase inhibition activity amongst the pure compounds. To the best of our knowledge, this is first report on the phytochemicals, tyrosinase inhibition, anti-acetycholinesterase and antimicrobial activities of the leaves of G. axillaris

Chemical Compositions and Tyrosinase Activity of the Essential Oils of Alpinia aquatica

The essential oils obtained from the fresh rhizome, leaf, and pseudostem of Alpinia aquatica Roscoe. were hydrodistillated and analyzed using capillary gas chromatography (GC) and gas chromatography-mass spectroscopy (GC-MS). β-Pinene (11.7%), α-humulene (8.9%), aromadendrene (8.7%), and sabinene (7.7%) were the major components in the rhizome oil. The most abundant components of the leaf oil were germacrene D (21.3%), β-pinene (15.6%) and sabinene (12.1%), while α-humulene (19.8%), germacrene D (15.2%) and β-caryophyllene (8.7%) were the main constituents in the pseudostem oil. Antityrosinase assay revealed that all the three essential oils exhibited weak tyrosinase inhibition activities. The rhizome oil showed the highest inhibition activity with the value of 9.5% for the L-DOPA oxidation

ANTIOXIDANT ACTIVITY OF PIPER CANINUM AND CYCLOOXYGENASE-2 INHIBITION BY METHOXYLATED FLAVONES

Background: The crude extracts and pure compounds isolated from Piper caninum was studied for their bioactivities. Material and method: The present study was carried out with the following aims: (1) to quantify the total phenolic content and free radical scavenging activities of the crude extracts by Folin-Ciocalteu and 1,1-diphenyl-2-picrylhydrazyl free radical scavenging assay. (2) to determine the cyclooxygenase-2 inhibition activities of selected isolated compounds as assessed by molecular docking and in vitro cyclooxygenase-2 inhibition assay. Results: Methanolic extracts of Piper caninum exhibited the highest total phenolic content and free radical scavenging activities. All the pure compounds possessed significant cyclooxygenase-2 inhibition at physiological concentrations. Conclusion: Based on our findings of the molecular docking and in vitro study, we therefore suggest that Piper caninum methoxylated flavones are potent inhibitors of cyclooxygenase-2 at physiological concentrations

Chemical and paf activity of several Malaysian artocarpus

Phytochemical studies of Artocarpus lowii King,A. scortechinii King and A. teysmanii Miq. have resulted in the isolation of four new compounds and eight known compounds. Three new compounds have been successfully isolated from A. lowii King, i.e 2 ' ,4 ' -dihydroxy-4-methoxy-3 ' -prenyldihydrochalcone, 2 ' ,3,4 ' ,4-tetrahydroxy-3 ' - prenylchalcone and 2-hydroxyparatocarpin C. Three known compounds were identified as cycloheterophyllin, 2 ' ,4 ' ,4-trihydroxy-3 ' -prenylchalcone and 4-hydroxylonchocarpin. A new compound was isolated from A. scortechinii King and was identified as 2 ' ,4 ' ,5 ' ,5- tetrahydroxy-3-geranyl-7,8-(2,2-dimethyl-6 H -pyrano)-6-prenylflavone together with three known compounds, i.e arto nin E, artobiloxanthone and lupeol 3-acetate. Four known compounds were isolated from A. teysmanii Miq., which were identified as artonin E, artobiloxanthone, artonol B and cycloartobiloxanthone. The structures of all compounds were established based on spectral studies using nuclear magnetic resonance spectroscopy, mass spectrometry, infrared spec troscopy and ultraviolet spectroscopy. The biological studies on the crude extracts and pure compounds of these three species showed that several pure compounds have signi ficant biological activit y especially in the platelet aggregation assays. Cycloheterophy llin, artonin E, isobavachalcone and 2 ' ,4 ' - dihydroxy-4-methoxy-3 ' -prenyldihydrochalcone totally inhibited ADP-induced platelet aggregation compared to standard aspirin which suppressed only 31.6% of the platelet aggregatio

Chemical compositions of the rhizome oils of two Alpinia species of Malaysia

The essential oils obtained by hydrodistillation of the rhizomes of Alpinia aquatica Rosc. syn. Alpinia melanocarpa and Alpinia malaccensis Roscoe were analysed by capillary gas chromatography and gas chromatography-mass spectrometry. Eighteen compounds, representing 98.4% of the essential oil were identified in A. aquatica rhizome oil, with ß-sesquiphellandrene in 36.5% being the major constituent, while 20 compounds representing 99.7% of the rhizome oil of A. malaccensis were identified, among which methyl (E)-cinnamate (78.2%) was the major constituent

In vitro antimicrobial activities of chloroformic, hexane and ethanolic extracts of citrullus lanatus var. citroides (wild melon)

To test the antimicrobial activities of crude chloroform, hexane and ethanol extracts of leaves, stem, fruits and seeds from Citrullus lanatus var. citroides (CL) against bacteria (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis and Proteus vulgaris) and fungi (Aspergillus nigar and Candida albican). Antimicrobial properties of CL were tested using cup-plate diffusion method and disc diffusion. Analysis of the data revealed that, the chloroform extract of the fruit exhibited the highest antibacterial activity. It showed antibacterial activity against S. aureus: 36 mm, B. subtilis; 38 mm, E. coli; 37 mm, P. valgaris; 23 mm and P. aerguinosa; 19 mm. The ethanolic extract of the fruit pulp and stem showed the highest antifungal activity on C. albican (41 mm). A. nigar was very sensitive to the chloroform extract of the seed (37 mm) and the ethanolic extract of the leaves (37 mm). Results were compared concurrently to standard drugs; clotrimazole and gentamicin. Based on the current findings, it can be concluded that this plant has antimicrobial activity, which is as potent as standard antimicrobial drugs against certain microorganisms

Total phenolic, antioxidant, antimicrobial, activities and toxicity study of Gynotroches Axillaris Blume (Rhizophoraceae)

The antioxidant activity and the total phenolic content, as well as the influence of petroleum ether, chloroform and methanol extracts from the leaves of Gynotroches axillaris, on micro- organisms were studied. The total phenolic contents were evaluated by using Folin-Ciocalteu reagent and the obtained values ranged from 70.0 to 620 mg GAE/g. The efficiency of antiox- idation, which was identified through the scavenging of free radical DPPH, exhibited that the highest IC50 was in the methanolic extract (44.7 μg/mL) as compared to the standard ascorbic acid (25.83 μg/mL) and to standard BHT (17.2 μg/mL). In vitro antimicrobial activity of ex- tracts was tested against Gram-negative bacteria, Gram-positive bacteria and fungi. Methanol extract showed activity in the range (225-900 μg/mL) with both types, while petroleum ether and chloroform extracts were only active with Bacillus subtilis. The three extracts strongly inhibited all fungi with activity 225-450 μg/mL. The toxicity test against brine shrimps indi- cated that all extracts were non-toxic with LC50 value more than 1000 μg/mL. The finding of this study supports the safety of these extracts to be used in medical treatments