64 research outputs found
Biotransformation of sesquiterpenoids having α,β-unsaturated carbonyl groups with cultured plant cells of Marchantia polymorpha
The biotransformation of sesquiterpenoids having an α,β-unsaturated carbonyl group, such as -santonin (1), lancerodiol p-hydroxybenzoate (2), 8,9-dehydronootkatone (3) and nootkatone (4), with cultured suspension cells of Marchantia polymorpha was investigated. It was found that the C-C double bond of 1 and 2 was hydrogenated to give 1,2-dihydro--santonin (5) and 3,4-dihydrolancerodiol p-hydroxybenzoate (6), respectively, while the allylic position of the C-C double bond of 3 and 4 was hydroxylated to give 13-hydroxy-8,9-dehydronootkatone (7) and 9-hydroxynootkatone (8), respectively
Phytochemical characterization and biological activities of green tea (Camellia sinensis) produced in the Azores, Portugal
Background: Green tea is not only one of the most widely consumed beverages worldwide, but is also known
for its health promoting and therapeutic effects. Green tea is cultivated in areas with high humidity and acidic
soils in China, Indonesia and Japan. Those places have well-marked dry and rainy seasons. In opposite, Azores have a climate with constant average annual rainfall and, unlike eastern regions, relatively constant air humidity throughout the year. While a brand implemented on the Portuguese market, the quality of green tea produced in Azores must be guaranteed. Quality control measures based on phytochemical determination of the chemical composition and biological activities are needed in order to address whenever climate changes interferes significantly with composition and biological effects.
Purpose: Make the phytochemical characterization of various extracts of green tea leaves coming from Azores
and evaluate the anti-cancer activities of the extracts in order to compare the obtained results with those of teas coming from eastern regions.
Methods: Phytochemical characterization (catechins, oxyaromatic acids, flavonols, alkaloids and theanine) and
total catechins contents (TCC) was performed by using HPLC-DAD analysis, in infusions (5–7 min and 30 min),
maceration and methanolic extracts of Camellia sinensis samples coming from Azores, Portugal. The antioxidant activity of extracts was measured by the DPPH assay and the total phenolics contents (TPC) were estimated using the Folin-Ciocalteu colorimetric method. The cytotoxic activity towards drug sensitive and multidrug-resistant leukemia cell lines was determined by the resazurin assay.
Results: The TCC was higher in methanolic extracts and lower in maceration, as epigallocatechin gallate (EGCG) and epicatechin gallate (ECG) concentrations were significantly higher in methanolic extracts and were only residual in maceration extracts. Maceration extracts showed the highest content of gallic acid, indicating that methanol extracts contained more flavonols of higher molecular weight and/or that maceration may lead to the degalloylation of catechins. The amount of o-caffeoylquinic acid extracted was significantly higher in methanolic samples. Short-term extraction at high temperatures resulted in high amounts of neochlorogenic acid. The contents of glycosylated quercitin-3-d-galactoside and kaempferol-3-glucoside were small in maceration samples and high in methanolic samples. Caffeine was easily extracted by methanol (99%) compared with water, while extraction of the amino-acid l-theanine was impossible with methanol. TPC values correlated linearly with DPPH• IC50, with infusion samples showing the best antioxidant capacities. The aqueous and the methanol/water extracts were active in multidrug-resistant and drug sensitive cancer cells.info:eu-repo/semantics/publishedVersio
In vitro anti-inflammatory and acetylcholinesterase inhibition efficiency of plant extracts from Sinai-Egypt
635-641Ten plant extracts were prepared and tested in in vitro assays against COX-2, COX-1 and acetylcholinesterase with evaluation of their antioxidant properties. The tested extracts exhibited varied anti COX-2 effect and they were superior to celecoxibe (inhibition percentage was 42.67% at 50 µg/mL), reference drug. Lavandula coronopifolia and Scrophularia Libanotica extracts were the efficient inhibitors (100% and 91% at 50 µg/mL respectively). Launaeaspinosa and Pulicaria undulata were the powerful AChE inhibitor (IC50 values were 16.69 and 29.06 µg/mL, respectively) followed with L. coronopifolia and S.libanotica extracts (IC50 values were 61.89 and 49.83 µg/mL, respectively) and they were efficient in scavenging superoxide radicals and metal ions, nitric oxide formation inhibition, as well as, lipid peroxide production suppression. L. coronopifolia and S. Libanotica extracts can be introduced as natural cyclooxygenase-2 inhibitors without affecting cyclooxygenase-1 whereas L. spinosa and P. undulata extracts were potent suppressor for AChE with robust antioxidant properties which suggest the possibility of using the four extracts, L. coronopifolia, S. libanotica, L. spinosa and P. undulata as natural agent in treating neurodegenerative disorder
In vitro anti-inflammatory and acetylcholinesterase inhibition efficiency of plant extracts from Sinai-Egypt
Ten plant extracts were prepared and tested in in vitro assays against COX-2, COX-1 and acetylcholinesterase with evaluation of their antioxidant properties. The tested extracts exhibited varied anti COX-2 effect and they were superior to celecoxibe (inhibition percentage was 42.67% at 50 µg/mL), reference drug. Lavandula coronopifolia and Scrophularia Libanotica extracts were the efficient inhibitors (100% and 91% at 50 µg/mL respectively). Launaeaspinosa and Pulicaria undulata were the powerful AChE inhibitor (IC50 values were 16.69 and 29.06 µg/mL, respectively) followed with L. coronopifolia and S.libanotica extracts (IC50 values were 61.89 and 49.83 µg/mL, respectively) and they were efficient in scavenging superoxide radicals and metal ions, nitric oxide formation inhibition, as well as, lipid peroxide production suppression. L. coronopifolia and S. Libanotica extracts can be introduced as natural cyclooxygenase-2 inhibitors without affecting cyclooxygenase-1 whereas L. spinosa and P. undulata extracts were potent suppressor for AChE with robust antioxidant properties which suggest the possibility of using the four extracts, L. coronopifolia, S. libanotica, L. spinosa and P. undulata as natural agent in treating neurodegenerative disorder
Cembranoids with 3,14-Ether Linkage and a Secocembrane with Bistetrahydrofuran from the Dongsha Atoll Soft Coral Lobophytum sp.
Four new cembranoids, lobophylins A–D (1–4), and one novel secocembrane, lobophylin E (5) were isolated from a soft coral Lobophytum sp. The structures of new metabolites were elucidated on the basis of extensive spectroscopic methods. Among these metabolites, 1–4 are rarely found cembranoids possessing a tetrahydrofuran moiety with a 3,14-ether linkage. In addition, 5 is the first secocembrane possessing two tetrahydrofuran moieties with 3,14- and 4,7-ether linkages
Bioactive Hydroperoxyl Cembranoids from the Red Sea Soft Coral Sarcophyton glaucum
A chemical investigation of an ethyl acetate extract of the Red Sea soft coral Sarcophyton glaucum has led to the isolation of two peroxide diterpenes, 11(S) hydroperoxylsarcoph-12(20)-ene (1), and 12(S)-hydroperoxylsarcoph-10-ene (2), as well as 8-epi-sarcophinone (3). In addition to these three new compounds, two known structures were identified including: ent-sarcophine (4) and sarcophine (5). Structures were elucidated by spectroscopic analysis, with the relative configuration of 1 and 2 confirmed by X-ray diffraction. Isolated compounds were found to be inhibitors of cytochrome P450 1A activity as well as inducers of glutathione S-transferases (GST), quinone reductase (QR), and epoxide hydrolase (mEH) establishing chemo-preventive and tumor anti-initiating activity for these characterized metabolites
Potency of extracts from selected Egyptian plants as inducers of the Nrf2-dependent chemopreventive enzyme NQO1
Cytotoxic and HIV-1 enzyme inhibitory activities of Red Sea marine organisms
BACKGROUND: Cancer and HIV/AIDS are two of the greatest public health and humanitarian challenges facing the
world today. Infection with HIV not only weakens the immune system leading to AIDS and increasing the risk of
opportunistic infections, but also increases the risk of several types of cancer. The enormous biodiversity of marine
habitats is mirrored by the molecular diversity of secondary metabolites found in marine animals, plants and
microbes which is why this work was designed to assess the anti-HIV and cytotoxic activities of some marine
organisms of the Red Sea.
METHODS: The lipophilic fractions of methanolic extracts of thirteen marine organisms collected from the Red Sea
(Egypt) were screened for cytotoxicity against two human cancer cell lines; leukaemia (U937) and cervical cancer
(HeLa) cells. African green monkey kidney cells (Vero) were used as normal non-malignant control cells. The extracts
were also tested for their inhibitory activity against HIV-1 enzymes, reverse transcriptase (RT) and protease (PR).
RESULTS: Cytotoxicity results showed strong activity of the Cnidarian Litophyton arboreum against U-937
(IC50; 6.5 μg/ml ±2.3) with a selectivity index (SI) of 6.45, while the Cnidarian Sarcophyton trochliophorum showed
strong activity against HeLa cells (IC50; 5.2 μg/ml ±1.2) with an SI of 2.09. Other species showed moderate to
weak cytotoxicity against both cell lines. Two extracts showed potent inhibitory activity against HIV-1 protease;
these were the Cnidarian jelly fish Cassiopia andromeda (IC50; 0.84 μg/ml ±0.05) and the red algae Galaxura filamentosa
(2.6 μg/ml ±1.29). It is interesting to note that the most active extracts against HIV-1 PR, C. andromeda and
G. filamentosa showed no cytotoxicity in the three cell lines at the highest concentration tested (100 μg/ml).
CONCLUSION: The strong cytotoxicity of the soft corals L. arboreum and S. trochliophorum as well as the anti-PR
activity of the jelly fish C. andromeda and the red algae G. filamentosa suggests the medicinal potential of crude
extracts of these marine organisms.The Medical Research Council, the Technology Innovation
Agency and the University of Pretoria, South Africa.http://www.biomedcentral.com/bmccomplementalternmedam201
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