Simple Bench-Top Bioassays (Brine Shrimp and Potato Discs) for the Discovery of Plant Antitumor Compounds

Abstract

Advances in separation technology and spectral methodology have greatly simplified the science of phytochemistry. New challenges lie in the isolation of nature's trace phytochemicals which exert various bioactivities and, thus, present potential usefulness to mankind. To help meet these challenges in discovering novel plant antitumor compounds, we have developed two simple bench-top bioassays which conveniently expedite screening and activity-directed fractionation of active plant extracts. These are lethality to brine shrimp and the inhibition of crown gall tumors on discs of potato tubers. Progress in this laboratory over the past three years is reviewed here. Our most exciting leads are the Annonaceous acetogenins of which bullatacin offers the best potential for antitumor drug development; the potent pesticidal effects of these new agents, which act via mitochondrial inhibition, also offer economic potential.In 1992, about 1,130,000 people in the United States were diagnosed as having cancer (excluding skin cancers); also during this year about 520,000 people (1,400 people/day) in the U.S. died of cancer; there has been a steady rise in our cancer mortality rate in the last half-century in spite of the fact that 51% of the cancer patients (excluding those with skin cancer), through medical and chemotherapeutic intervention, can now expect to survive with their disease for at least five years following diagnosis (7). Thus, the search for new anticancer agents, especially those effective against breast, prostate, ovarian, and cervical cancers, has been given a top priority at the National Cancer Institute (NCI) (Broder, S.; letter to NIH grantees, December 12,1991).To help in this search, NCI has, from 1957 through 1991, screened, for antitumor activities, more than 156,000 plant extracts from over 53,000 plant species (2,3; McCloud, T.G., NCI/FCRF personal communication, 1992). Through the combination of efforts at NCI and various pharmaceutical companies, several chemically useful antitumor drugs have been developed and are marketed from the Catharanthus alkaloids and the lignans of Podophyllum species (4, 5). Current hopes are high that camptothecin and/or its analogues (6) and taxol and/or its congeners (7,8) will also survive the rigors of clinical testing and become routinely 0097-6156/93A)534-0112$07.50/0

Cytotoxic Long-chain Alkene and Terpene Isolated from the Methanol Extract of the Air-dried Leaves of Pipturus arborescens C.B. Rob

“…It has the complete and effective range to test the toxicity as well as for various assays (Kanwar, 2007). The brine shrimp lethality assay represents a rapid, inexpensive and simple bioassay for testing plant extracts bioactivity which in most cases correlates reasonably well with cytotoxic and anti-tumor properties (McLauglin et al, 1993). The cytotoxicity of Isolate 2 provides baseline information that this is possible for clinical use indicative of anticancer, antiviral and other wide-range of pharmacological activities (Sayeed et al, 2003).…”

Free radical-scavenging activity of sequential leaf extracts of Embothrium coccineum

“…Larvae were considered dead only if they did not move their appendages for 10 s during observation. The concentration killing fifty percent of the larvae (LC 50 ) was calculated using the probit analysis method [27].…”

Toxicity of <I>Fusarium solani</I> Strains on Brine Shrimp (<I>Artemia salina</I>)

“…Brine shrimp lethality test for larvae nauplii was used to determine the toxicity of culture filtrates of F. solani (McLaughlin et al, 1993). 1.2.1 Sample preparation Two millilitres from each dilution of culture filtrate, lyophilized filtrate or fraction were transferred in sample vials, used for bioassay.…”

“…Brine shrimp bioassay is very simple, rapid and inexpensive method and has successfully been used as prescreening of bioactive compounds having antitumor activity (McLaughlin et al, 1993). This test has been established as a safe, practical and economical method for the determination of the bioactivity of synthetic compounds (Almeida et al, 2002), mycotoxins of fungal pathogens (Schmidt et al, 1995), marine products (Ara et al, 1999) as well as higher plant products (Nino et al, 2006, Stefanello et al, 2006).…”