Records of Natural Products Articles

Two known triterpenoids, friedelin and aglaitriol, and a new dammarane triterpenoid, aglaitriol 3-caffeate, have been isolated and identified in the chloroform bark extract of Drypetes acuminata P.I. Forst. (Putranjivaceae) from Paluma, north Queensland, Australia. The compounds were screened for antimicrobial and cytotoxic activity. Aglaitriol showed potent cytotoxic activity against three human tumor cell lines (MCF-7, MDA-MB-231, and 5637). Aglaitriol 3-caffeate showed moderate antibacterial activity against Staphylococcus aureus and Escherichia coli. A molecular docking analysis suggests topoisomerase II may be a likely protein target for aglaitriol.

Volatile oils composition from leaves and ripe fruits of pink pepper (Schinus terebinthifolius Raddi) growing in Tunisia were investigated using GC-FID and GC-MS techniques. Volatile oil extraction was achieved by hydrodistillation (HD) using a Clevenger apparatus and by supercritical fluid extraction (SFE) using carbon dioxide. All plant organs, gave SFE extracts chiefly composed by a -pinene, a -phellandrene, b -phellandrene, germacrene D and bicyclogermacrene. In the case of the fruits, both extraction techniques gave volatile oils of similar composition; whereas the comparison between the HD and SFE leave oils revealed important differences in the content of a -pinene (6.1 % vs traces), a -phellandrene (22.7 % vs 0.8 %) and b -phellandrene (14.6 % vs 1.2 %). All volatile samples were evaluated against yeasts and dermatophyte strains, being more active against Cryptococcus neoformans, particularly the volatile oil from the fruits, with MIC values of (0.32-0.64) mg/mL.Moreover, this oil revealed an inhibitory effect on germ tube formation in C. albicans at sub-inhibitory concentration. At the concentration of MIC/8 the inhibition of filamentation was more than 70 %.

In this study, the fatty acids composition, the total flavonoids, phenolics, and mineral contents of Trigonella species belonging to Cylindricae Section (T. spruneriana, T. sibthorpii, T. kotschyi, T. mesopotamica, T. cylindricae, T. cilicica, T. filipes, T. velutina, T. strangulata and T. smyrnea) were determined. Diosgenin content in seeds and aerial parts of these species was investigated by RP-HPLC. Furthermore, the phytochemical profiles and radical scavenging activities of the plants were evaluated. The oils contained high proportions of α-linolenic (29.7-42.1 %) and linoleic acids (26.6-40.3 %). All the seed extracts had higher concentrations of total flavonoids and phenolics than those of aerial parts. T. strangulata and T. spruneriana seeds showed the highest total phenolics (201.35±0.51 and 191.90±0.86 mg GAE/g, respectively) and flavonoids contents (121.84±0.05 and 128.04±0.09 mg RE/g, respectively). For the DPPH radical scavenging assay, the extracts of four species of Trigonella showed moderate radical scavenging activity. The seeds contained high concentrations of potassium, calcium and phosphorus while the aerial parts were rich in calcium and potassium. Phytochemical screening tests showed that saponins, flavonoids, coumarins and fixed oils were main secondary metabolites. The highest diosgenin level was detected in T. cilicica seed and aerial part extracts (0.52±0.013 and 0.16±0.005 mg/g, respectively).

Nine chiral compounds (1−9) were isolated from the static fermentation culture of a shark gill-derived fungus Penicillium polonicum AP2T1. These compounds include a new acetylenic aromatic ether (1 , (-)-WA ), four alkaloids ( a urantiomide C ( 2 ), fructigenine A (3), cyclopenin (4) and cyclopenol (5)) and four oxygenated compounds ((R)-penipratynolene (6), (3S,4S)-3,4-dihydro-3,4,8-trihydroxyl-naphthalenone (7), verrucosidin (8) and norverrucosidin (9)). Their structures were elucidated by MS, NMR , optical rotation and circular dichroism (CD) . In antimicrobial tests , compounds 1–4, 6 and 8–9 showed weak antibacterial activity against Staphylococcus aureus, Bacillus subtilis, and/or Escherichia coli.Compounds 3, 8 and 9 also exhibited moderate toxicity against Artemia salina larva , and showed cytotoxicity against human colon cancer cell line HCT116.

hrough current phytochemical investigation on dichloromethane (DCM) fraction of 80% methanolic extract of Tricholepis eburnea, seven chemical constituents were isolated and their structures were elucidated by spectroscopic analyses. Two of them were identified as new flavonoids as trichonoide A (1) and trichonoide B (2), while the other five known constituents β-sitosterol (3), 3-O-acetyl-β-stigmastanol (4), 3β,17β,20-trihydroxy-l-oxo-(20R, 22 R)- witha-5,14,24-trienolide (5), pectolinaringenin (6), and dillenetin (7) were isolated for the first time from this species .

A combination of solid-phase-extraction (SPE) and reversed-phase preparative high-performance liquid chromatography (prep-HPLC) of the methanolic extract of the aerial parts of Artemisia splendens (common name: “Asia Minor Wormwood”), an endemic Iranian species, afforded Z- and E-melilotosides (1 and 2), Z- and E-4-methoxy-melilotosides (3 and 4), and a new dimer, bis-ortho-Z-melilotoside (5, named: splendenoside). Whilst the structures of these compounds (1-5) were elucidated unequivocally by spectroscopic means, the in vitro free-radical-scavenging property of 1-5 was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. This is the first report on the occurrence of any melilotoside derivatives in the genus Artemisia.

This study evaluated for the first time the antibacterial activity, cell viability and migration ability on   3T3 murine fibroblast  cells of extracts and isolated compounds [lupeol (1), hexamethylcoruleoellagic acid (2) and a mixture of 1 and betulinaldehyde (3)] of Myrciaria ferruginea. In antibacterial assays extracts were susceptible only against S. aureus (MIC 500 μg/mL) and S. epidermidis (MIC ranging from 7.8 to 500 μg/mL) and compounds 1-3have shown no significant activity. In trials for c ell viability, with exception of MeOH-H 2O fraction from leaves (viable cells > 90%), both the crude extract and other fractions showed inhibition of cell growth (viable cells ≤ 80% at 15.625 and 31.25 μg/mL); while the samples from stems, with the exception of CHCl 3 fraction that showed strong cytotoxic effect at the lowest concentration tested (15.625 μg/mL), the other fractions were not cytotoxic. Compounds (1-3) inhibited cell viability in dose dependent manner (15.625 to 500 μg/mL). Mixture containing 1 and 3 showed inhibitions only in concentrations greater than 62.5 μg/mL while compound 2 decreased from the lowest concentration tested. In scratch wound assay, these compoundsnot increased the population of fibroblasts at concentrations less than 62.5 μg/mL.

The essential oil (EO) was obtained by hydrodistillation from the aerial parts of Lepechiniaradula Benth Epling (Lamiaceae) from Ecuador. Thirty-four compounds accounting to 93.4% of the total oil were identified. The main constituents of the essential oil were δ-3-carene (19.9%), β-pinene (17.0%), (E)-β-caryophyllene (9.7%) and (E-E)-α-farnesene (9.4%). The essential oil of L.radula possessed strong antifungal activity against Trichophytonrubrum (ATCC® 28188) and Trichophytonmentagrophytes (ATCC® 28185).

An ethyl acetate (EtOAc) extract of Laurencia nidifica was found to have toxic effect against brine shrimp larvae (Artemia salina). Bioassay-guided fractionation of the EtOAc extract resulted in the isolation of four known halogenated sesquiterpenes, laurinterol (1), isolaurinterol (2), aplysin (3), and a -bromocuparene (4). Their structures were established on the basis of spectral analysis and comparison with literature data. Among isolated compounds, only laurinterol showed strong toxicity against A. salina. Further experiments revealed that laurinterol also exhibited repellent activity against the maize weevil Sitophilus zeamais , insecticidal activity against the termite Reticulitermes speratus, and acetylcholinesterase (AChE) inhibitory effect . This is the first report of insecticidal and repellent activities of laurinterol.

An ethyl acetate (EtOAc) extract of Laurencia nidifica was found to have toxic effect against brine shrimp larvae (Artemia salina). Bioassay-guided fractionation of the EtOAc extract resulted in the isolation of four known halogenated sesquiterpenes, laurinterol (1), isolaurinterol (2), aplysin (3), and a -bromocuparene (4). Their structures were established on the basis of spectral analysis and comparison with literature data. Among isolated compounds, only laurinterol showed strong toxicity against A. salina. Further experiments revealed that laurinterol also exhibited repellent activity against the maize weevil Sitophilus zeamais , insecticidal activity against the termite Reticulitermes speratus, and acetylcholinesterase (AChE) inhibitory effect . This is the first report of insecticidal and repellent activities of laurinterol.

The essential oils of Centaurea aggregata subsp. aggregata, C. balsamita and C. behen collected in the same habitat from Turkey, have been investigated. A total of 26, 54 and 26 components were identified in C. aggregata subsp. aggregata, C. balsamita and C. behen, respectively. The main constituents of the investigated populations of the three taxa have been revealed as follows: Centaurea aggregata subsp. aggregata: hexadecanoic acid (35.8%), phytol (7.2%), caryophyllene oxide(6.0%), spathulenol (6.0%); C. balsamita: hexadecanoic acid (23.0%), spathulenol (8.9%), germacrene D (2.1%); C. behen: hexadecanoic acid (32.7%), germacrene D (14.8%), and phytol (12.3%).

A new compound, 1,2-di-(syringoyl)-β-D-glucopyranose, together with erigeside C, were isolated from the roots of Acanthus ilicifolius. The structure of the new compound was elucidated by extensive spectroscopic methods, including 1D, 2D NMR and HRESIMS spectroscopic data. The cytotoxic activities of these compounds were evaluated against HepG2, A-549, and HeLa cells in vitro. However, none of them showed cytotoxic activities.

A new phloroglucinol derivative, identified as 3-benzoyl-3-hydroxy-5-(3-methylbut-2-en-1-yl)cyclopentane-1,2,4-trione (1 ), together with eight previously reported compounds, quercetin, myricitrin, hypericin, biapeginin, pseudohypericin, myricetin, 1,3,5,6-tetrahydroxyxanthone, and β-sitosterol were isolated from the chloroform, ethyl acetate and butanol extracts of the aerial part of Hypericum afrum (Lam.). Their structures were elucidated by spectroscopic analyses, including 1D-, 2D-NMR and HRESIMS. The EtOAc extract showed moderate MAO-A inhibition with an IC 50 value of 3.35 μg/mL. Bioassay-guided fractionation of the EtOAc extract resulted in the isolation of quercetin as the active component exhibiting MAO-A inhibitory activity with an IC 50 value of 1.25 μM.

The chemical compositions of the essential oils obtained by hydrodistillation from the aerial parts of Myrsine rubra, Myrsine gardneriana and Myrsine parvifolia and the fruits of Myrsine parvifolia were elucidated by a combination of GC and GC-MS analyses. The main constituents of the native M. parvifolia were caryophyllene oxide (14.4%), β-caryophyllene (12.6%) and γ-Muurolene (7.9%) of the leaves oil and β-caryophyllene (11.7%), δ-Cadinene (7.1%) of the fruit oil. The volatile oil of the endemic M. rubra leaves was dominated by β-caryophyllene (17.2%), γ-Muurolene (11.1%), Germacrene B (10.0%). The essential oil of the native M. gardneriana leaves was characterized by β-caryophyllene (18.0%), γ-Muurolene (8.4%). These three Myrsine species are similar in the dominance of sesquiterpenes. By contrast, monoterpenes were found only in the volatile oil from the fruits of M. parvifolia. To the best of our knowledge, this study is the first report on the volatile constituents of M. rubra, M. gardneriana, M. parvifolia.

Volatile composition of Chenopodium murale from Değirmenlik and Salamis locations of Cyprus were trapped with headspace solid-phase microextraction (HS-SPME) technique and analyzed by GC-MS. Twenty-one compounds were identified comprising of 80.5% of the volatile sample from the Değirmenlik and twenty-six compounds were identified comprising of 82.2% of the volatile from the Salamis sample. Volatiles of C. murale from Değirmenlik contained 18.7% benzaldehyde, 8.6% yomogi alcohol 6.8% 1-hexanol and 6.5% dihydromyrcenol as the main components whereas volatiles of the sample from Salamis contained 20.5% yomogi alcohol, 14.5% camphor, 8.1% 1-hexanol and 6.6% 2-ethyl-hexanol. The volatiles of C. murale from both locations contained unexpected irregular monoterpene yomogi alcohol which is previously known to be restricted to Asteraceae genus. Both locations showed variations in their compositions which suggests the chemotype variation could be observed from this species.