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ABSTRACT: Two new illudane sesquiterpenes, paneolic acid and paneolilludinic acid, along with a known antibiotic diterpene, pleuromutilin, were isolated from the mycelial solid cultures of Panaeolus retirugis. Their structures were elucidated on the basis of spectroscopic analysis. Both compounds exhibited antibacterial activity against Staphylococcus aureus, and paneolic acid showed cytotoxicity to HL60 cell with an IC50 of 18.9 microg/ml.
The Journal of Antibiotics 12/2004; 57(11):721-5. · 1.65 Impact Factor
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ABSTRACT: Four new sesquiterpene dilactones, mikamicranolide (1), 11 beta,13-dihydromikamicranolide (2), 3 alpha-hydroxy-11 beta,13-dihydrodeoxymikanolide (3), and 2 beta,3 beta-dihydroxy-11 beta,13-dihydrodeoxymikanolide (4), were isolated from the whole plants of Mikania micrantha. Their structures were elucidated on the basis of spectroscopic analysis. Compounds 1 and 2 possess an unusual rearranged 12,8-germacranolide sesquiterpene skeleton.
Journal of Natural Products 05/2004; 67(4):734-6. · 3.13 Impact Factor
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ABSTRACT: Two new phenolic compounds, polygalolide A (1) and polygalolide B (2), together with three known xanthones were isolated from the roots and stems of Polygala fallax. The structures of 1 and 2 were elucidated on the basis of spectroscopic evidence.
Journal of Natural Products 04/2003; 66(3):441-3. · 3.13 Impact Factor
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ABSTRACT: Two new sesquiterpene glucosides, litchiosides A (1) and B (2), were obtained along with pumilaside A (3) and funingensin A (4) from lychee (Litchi chinensis Sonn.) seed. Their structures were elucidated on the basis of spectroscopic and chemical evidence. The in vitro antitumour activity of compounds 1–4 against A549, LAC, Hela, and Hep-G2 cell lines was determined using the MTT colourimetric assay. Pumilaside A (3) exhibited significant activity against all the tested cell lines with IC50 values of 0.012–6.29 μM, and funingensin A (4) showed moderate activity against Hep-G2 cells (IC50 = 39.27 μM), while litchiosides A (1) and B (2) were found to be inactive.
Food Chemistry.
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ABSTRACT: Five previously uncharacterised polyphenols, ethyl gallate (2), 1-β-O-galloyl-d-glucopyranose (3), methyl brevifolin carboxylate (4), brevifolin (5) and 4-O-α-l-rhamnopyranosyl-ellagic acid (8), and three previously identified polyphenols, gallic acid (1), corilagin (6) and ellagic acid (7), were isolated from longan seeds. Their structures were identified by spectroscopic and chemical methods including HRESIMS and NMR. Eight polyphenols exhibited scavenging activity towards DPPH radicals with SC50 values of 0.80–5.91 μg/ml and towards superoxide radicals with SC50 values of 1.04–7.03 μg/ml. The radical-scavenging activity of the newly characterised polyphenols was comparable to that of gallic acid, corilagin and ellagic acid.
Food Chemistry.
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ABSTRACT: Eleven flavonoids including a new flavone glycoside, 7,3′-dihydroxy-4′-methoxyflavone-7-O-β-glucopyranoside, and a quinolizidine alkaloid, lupanine, were isolated from the seeds of two Ammopiptanthus (Leguminosae) species, Ammopiptanthus mongolicus and Ammopiptanthus nanus. 7,3′-Dihydroxy-4′-methoxyflavone and lupanine were the major constituents in the seeds of both species. The patterns of seed flavonoids presented a clear systematic relationship between the two species. The simple seed alkaloid composition was presumed to be responsible for the weak defense capability of the seeds to insect pests in both species.
Biochemical Systematics and Ecology 35(5):274-280. · 0.93 Impact Factor
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ABSTRACT: Longan fruit pericarp was extracted with 50% ethanol employing high pressure (500 MPa) and conventional extraction methods. Total phenolic contents of high pressure-assisted extract of longan (HPEL) and conventional extract of longan (CEL) were 20.8 and 14.6 mg gallic acid equivalents/g dry weight, respectively. Subsequently, the antioxidant activities of these extracts were analyzed employing various antioxidant model systems including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, superoxide anion radical scavenging activity, total antioxidant capacity, and lipid peroxidation inhibitory activity. In addition, anticancer activity was also tested using HepG2, A549, and SGC 7901 cancer cell lines. HPEL showed excellent antioxidant and anticancer activities and were higher than CEL. Three phenolic compounds, namely gallic acid, corilagin, and ellagic acid, were identified and quantified by external standard methods. Compared with CEL, HPEL exhibited higher extraction effectiveness in terms of higher extraction yield, higher phenolic content, and higher antioxidant and anticancer activity with shorter extraction time.Industrial relevanceThis study was focused to evaluate the antioxidant and anticancer activity of longan fruit pericarp by high-pressure treatment. The high-pressure treatment provided a better way of utilizing longan fruit pericarp as a readily accessible source of the natural anticancer and antioxidant in food and pharmaceutical industry.
Innovative Food Science & Emerging Technologies 10(4):413-419. · 3.03 Impact Factor
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ABSTRACT: Postharvest browning of litchi fruit results in a short life and a reduced commercial value. The experiments were conducted to separate, purify and identify the polyphenol oxidase (PPO) substrates that cause litchi fruit to brown. PPO and its substrates were, respectively, extracted from fruit pericarp tissues. The substrates for litchi PPO were separated and purified using polyamide column chromatography, silica gel column chromatography and preparative thin layer chromatography. The substrate was further identified by 0.5% FeCl3 solution and enzymatic reaction with litchi PPO. On the basis of UV, 1H NMR, 13C NMR, and ESI-MS data, the direct substrate for the PPO from litchi fruit pericarp tissues was identified to be (−)-epicatechin.
Food Research International. 39(8):864-870.
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ABSTRACT: Postharvest browning of longan fruit results in a short life and a reduced commercial value. The experiments were conducted to separate, then purify and finally identify the polyphenol oxidase (PPO) substrates that cause longan fruit to brown. PPO and its substrates were, respectively, extracted from longan fruit pericarp tissues. The substrate for longan PPO was separated and purified using polyamide column chromatography, Sephadex LH-20 column chromatography and silica gel column chromatography, respectively. The substrate was further identified by 0.5% FeCl3 solution and enzymatic reaction with longan PPO. On the bases of UV, 1H NMR, 13C NMR, and ESI-MS data, the direct substrate for the PPO from pericarp tissues of longan fruit was identified to be (−)-epicatechin. Furthermore, the contents of (−)-epicatechin of pericarp tissues of longan fruit of two major cultivars were determined by high performance liquid chromatography (HPLC). The HPLC analysis exhibited that the contents of (−)-epicatechin of fruit pericarp of ‘Shixia’ and ‘Chuliang’ were 0.26 and 0.56 mg/g on fresh weight (FW) basis at harvest and 0.15 and 0.09 mg/g FW after 3 days of storage. The more rapid decrease in the (−)-epicatechin content of ‘Chuliang’ was due to the oxidization catalyzed by PPO, which was in agreement with the higher browning index.
LWT - Food Science and Technology. 41(10):1742-1747.
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ABSTRACT: Fruits of wampee [Clausena lansium (Lour.) Skeels] contain a significant amount of coumarins with many health benefits. The activity-guided separation of an ethyl acetate-soluble fraction on a polyamide column followed by silica gel column and high performance liquid chromatography (HPLC) preparation afforded a pure compound, which was identified to be 8-hydroxypsoralen based on the 1H, 13C NMR (nuclear magnetic resonance), and ESI-MS (electrospray ionisation mass spectrometric) analysis. This isolate exhibited good scavenging activities against DPPH radical and superoxide anion as well as significant reducing power. It also showed potent proliferation inhibitory activity against human hepatocellular liver carcinoma cell line (HepG2), human lung adenocarcinoma epithelial cell line (A549) and human cervical carcinoma cell line (HELA). This is the first report on the antioxidant and cytotoxic properties of C. lansium fruit extract. The food and pharmaceutical industry could be benefited by the usage of this extract containing this constituent.
Food Chemistry.
