in the American Midwest, due to the high value of black walnut trees, has led to certain studies being conducted about the particular relationship between the two species. Research has shown that juglone affects the yield of maize crops; however, the practice of pruning and usage of root barriers greatly reduce these effects. Some plants and trees are resistant to juglone including some species of maple (Acer), birch (Betula), and beech (Fagus). It is highly toxic to many insect herbivores. However, some of them, example Actias luna (Luna moth), can detoxify juglone (and related naphthoquinones) to non-toxic 1,4,5-trihydroxynaphthalene. It has also shown anthelmintic (expelling parasitic worms) activity on mature and immature Hymenolepis nana in mice. Napthoquinonic compounds also exhibit antimicrobial activity. Juglone has been studied for its anticancer properties. It has been shown to decrease the probability of intestinal tumors in rats that have been exposed to carcinogens. One of the potential pathways through which juglone achieves its anticancer properties is through the formation of the semiquinone radical; the semiquinone radical causes superoxide anion radicals to form which can lead to apoptosis when present in large concentrations. This conversion from juglone to semiquinone radical that causes the superoxide anion radical to form takes place in the mitochondria as well as the cytosol. Uses Juglone is occasionally used as a herbicide. Traditionally, juglone has been used as a natural dye for clothing and fabrics, particularly wool, and as ink. Because of its tendency to create dark orange-brown stains, juglone has also found use as a coloring agent for foods and cosmetics, such as hair dyes. Spectral data The spectral data for juglone are consistent with the structure. The IR spectrum for juglone shows peaks at 3400, 1662, and 1641 cm−1 which are characteristic respectively of the hydroxyl and two carbonyl groups. The 13C NMR spectrum shows 10 peaks, including signals at 160.6, 183.2, and 189.3 ppm for the hydroxyl and two carbonyl carbons. See also Plumbagin References Herbicides Natural dyes Food colorings 1,4-Naphthoquinones Hydroxynaphthoquinones