A Chemical Screening Strategy for the Dereplication and Prioritization of HIV-Inhibitory Aqueous Natural Products Extracts

Cardellina, H I I John; Munro, Murray H. G.; Fuller, Richard W.; Manfredi, Kirk P.; McKee, Tawnya C.; Tischler, Mark; Bokesch, Heidi R.; Gustafson, Kirk R.; Beutler, John A.; Boyd, Michael R.

doi:10.1021/np50097a016

Cited by 92 publications

(62 citation statements)

References 10 publications

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“…In some cases it has become a common procedure to remove tannins from plant extracts before biological activity tests are conducted (Cardellina et al, 1993). However, in the present work and also in other studies (Kashiwada et al, 1992), it has been shown that some hydrolysable tannins display selective cytotoxicity.…”

Section: Resultsmentioning

confidence: 51%

In vitroantiprotozoal activity of extract and compounds from the stem bark ofCombretum molle

Asres

Bučar

Knauder

et al. 2001

Phytotherapy Research

105

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The antiprotozoal activity of the Ethiopian medicinal plant Combretum molle (R. Br. ex G. Don.) Engl & Diels (Combretaceae) was evaluated by in vitro testing against Plasmodium falciparum, Trypanosoma brucei rhodesiense, Trypanosoma cruzi and Leishmania donovani. The acetone fraction of the stem bark of this plant prepared by soxhlet extraction was inactive against the intracellular amastigotes of L. donovani and T. cruzi in murine peritoneal macrophages but showed significant activity against extracellular T. b. rhodesiense blood stream form trypomastigotes and trophozoites of P. falciparum with IC(50) values of 2.19 and 8.17 microg/mL, respectively. Phytochemical examination of the bioactive fraction resulted in the isolation of two tannins and two oleanane-type pentacyclic triterpene glycosides. One of the tannins was identified as the ellagitannin, punicalagin, whilst the structure of the other (CM-A) has not yet been fully elucidated. The saponins that were characterized as arjunglucoside (also called 4-epi-sericoside) and sericoside displayed no activity against any of the four species of protozoa tested. On the other hand, punicalagin and CM-A had IC(50) values of 1.75 and 1.50 microM, respectively, against T. b. rhodesiense and were relatively less toxic to KB cells (cytotoxic/antiprotozoal ratios of 70 and 48, respectively). The tannins also showed intermediate activity against P. falciparum, although their selectivity against these parasites was less favourable than the above. It appears that our findings are the first report of hydrolysable tannins exhibiting antitrypanosomal and antiplasmodial activities.

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Section: Resultsmentioning

confidence: 51%

In vitroantiprotozoal activity of extract and compounds from the stem bark ofCombretum molle

Asres

Bučar

Knauder

et al. 2001

Phytotherapy Research

105

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“…The authors concluded that the extracts contained RT inhibitors that &&are at least novel among the blue-green algae'' (Lau et al, 1993). Cardellina et al (1993) reported that about 15% of aqueous extracts from terrestrial plants, cyanobacteria, and marine invertebrates and algae exhibited HIV-antiviral activity in the National Cancer Institute's primary AIDS-antiviral screen. A considerable number of extracts were eliminated after removing anionic polysaccharides.…”

Section: 34mentioning

confidence: 99%

Anti-HIV Activity of Extracts and Compounds from Algae and Cyanobacteria

Schaeffer

Krylov

2000

Ecotoxicology and Environmental Safety

281

165

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“…Alternatively, the simplest explanation is that the effects of EGCG on many of its reported molecular targets are merely high-concentration effects or experimental artifacts that reflect the propensity of catechins and other polyphenolic substances to chelate metals and bind proteins in a nonselective manner (reviewed in Haslam, 1996). This is the main reason that the high-throughput pharmaceutical screening community has considered polyphenols and other tannins to be "nuisance" compounds that must either be removed from test samples or dereplicated prior to extensive evaluation in protein-based bioassay systems (i.e., enzyme or receptor) (Cardellina et al, 1993). If this is the case, only a relatively small number of the numerous molecular mechanistic studies reported for EGCG and other green tea products actually reflect physiologically relevant processes.…”

Section: Introductionmentioning

confidence: 99%

Epigallocatechin-3-gallate (EGCG): Chemical and biomedical perspectives

2006

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The compound (-)-epigallocatechin-3-gallate (EGCG) is the major catechin found in green tea [Camellia sinensis L. Ktze. (Theaceae)]. This polyphenolic compound and several related catechins are believed to be responsible for the health benefits associated with the consumption of green tea. The potential health benefits ascribed to green tea and EGCG include antioxidant effects, cancer chemoprevention, improving cardiovascular health, enhancing weight loss, protecting the skin from the damage caused by ionizing radiation, and others. The compound EGCG has been shown to regulate dozens of disease-specific molecular targets. Many of these molecular targets are only affected by concentrations of EGCG that are far above the levels achieved by either drinking green tea or consuming moderate doses of green tea extract-based dietary supplements. In spite of this, well-designed double-blinded controlled clinical studies have recently demonstrated the efficacy of green tea extracts and purified EGCG products in patients. Therefore, this review highlights results from what the authors believe to be some of the most clinically significant recent studies and describes current developments in the stereoselective total synthesis of EGCG.

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A Chemical Screening Strategy for the Dereplication and Prioritization of HIV-Inhibitory Aqueous Natural Products Extracts

Cited by 92 publications

References 10 publications

In vitroantiprotozoal activity of extract and compounds from the stem bark ofCombretum molle

In vitroantiprotozoal activity of extract and compounds from the stem bark ofCombretum molle

Anti-HIV Activity of Extracts and Compounds from Algae and Cyanobacteria

Epigallocatechin-3-gallate (EGCG): Chemical and biomedical perspectives

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