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Fungi of the genus Alternaria are commonly parasitic on plants and other organic materials. Many are in fact plant pathogens of field crops whereas others infect foodstuffs after harvest (1). They can grow at low temperatures and so may cause spoilage of fruits and vegetables during refrigera ...

The method described is based on that developed by Schuler and colleagues (1,2 and recently refined (3).

The chick embryo has been used for the study of experimental teratogenicity by various techniques (1–4). This chapter describes a method developed by Jelinek (5,6) that combines a standardized technique (CHEST I) with other techniques (CHEST II); it allows the administration of small amoun ...

Although there are many variations of assays measuring the ability of a test chemical to induce mutation in bacterial cells, by far the best known (and probably the best known of all mutagenicity tests) is the Ames test. The methods described in this chapter are largely based on those developed by Bruce ...

Chromosomal aberrations are implicated in the induction of both cancer and birth defects (1,2). The types of aberration that cause human disease are usually subtle rearrangements, e.g., reciprocal exchanges, which are not cell lethal. These are frequently difficult to detect microsco ...

Gene mutation assays in cultured mammalian cells may be used to give a measure of the response of the mammalian genome to potential mutagens, and yet they are rapid and simple to carry out when compared to the use of whole mammals. Many mammalian cell gene mutation assays are available, but only four cell li ...

The in vitro unscheduled DNA synthesis (UDS) assay performed in primary cultures of rat hepatocytes is a useful screen for DNA damage and repair. Although it gives no direct information about the number or type of DNA lesions or about the consequences of repair, it does detect repair of the type of DNA les ...

DNA is the target molecule for chemical and physical mutagens and carcinogens. These agents may attack DNA directly or modify other cel- lular processes associated with the integrity of the genome. The resulting alterations in the structure of DNA may either be irreversible, giving rise to mut ...

The increasing interest in immunotoxicology as a subtopic of toxicol- ogy acknowledges the growing recognition that the immune system and immunocompetence per se may be a sensitive and perhaps early indica- tor of toxicity. Indeed, accumulating evidence based on human and exper- imental ...

Chemotaxis and random migration of polymorphonuclear leukocytes can be determined in the presence of test chemicals. A change in the chemotactic index provides an indication of the cytotoxicity of compounds. The migration of polymorphonuclear leukocytes to the site of injury is an int ...

Allergic contact dermatitis is a delayed-type hypersensitivity reaction in the skin characterized by a tissue damaging inflammatory response. A wide variety of natural and synthetic chemicals have been shown to be capable of causing contact dermatitis (1).

Human A431 cells and mouse 3T3 cells are exposed in culture to UV light both in the presence and absence of test compound. Phototoxicity is expressed as a decrease in cell viability as determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay.

Spearmint has one major monoterpene, (−)-carvone, that constitutes up to 90% of all the monoterpenes present. Likewise, the major phenylpropanoid—rosmarinic acid—in spearmint accounts for up to 70% of the phenylpropanoids produced from the plant. These two compounds are each produced by ...

Rhodiola rosea is a multipurpose medicinal plant with adaptogenic properties: it increases the body’s nonspecific resistance and normalizes body functions. The commercial interest for roseroot-based products has quickly increased worldwide. Nearly all raw-materials ori ...

Catharanthus roseus is an indispensable source of the anticancerous alkaloids-vincristine and vinblastine, even though they are produced in trace amounts in vivo. In order to increase the yield of alkaloids, in vitro tissue culture studies are carried out which result in a large number of li ...

Recognition of medicinal plant species or plant characters can be accomplished through the use of genomic DNA sequences unique to a species, a group of species, or a species variant. An assay well-suited to this application is the Multiplexed Ligase-dependent Probe Amplification (MLPA) as ...

Hairy root clones of Rehmannia glutinosa were established via transformation with Agrobacterium rhizogenes ATCC15834. To optimize the culturing conditions for both root growth and catalpol production, the effects of various combinations of seven basal media, pH, and carbon sour ...

Limited native resources of paclitaxel from Taxus trees initiated the research to produce this compound by biotechnology. In vitro plant cell culture systems have been used for large-scale production of paclitaxel and related taxanes. In the past decade, several genes involved in the tax ...

Agrobacterium tumefaciens is used to develop a genetic transformation method for a medicinal plant Ruta graveolens. The direct plant regeneration strategy is preferred to callus line establishment. In vitro seedlings, 2- –to 3-wk-old, are used to excise hypocotyls and co-cultivated f ...

Plant transformation is an important tool with many applications in modern plant biology. Although this technique is primarily used to produce superior crop varieties, it is also being utilized to answer basic questions concerning gene function and regulation in contemporary funct ...