Burdock seeds have been researched to see if they possess a mechanism to protect the stomach and treat ulcers, possibly preventing the formation of ulcers. This study found that the preparations created from these seeds had a definite effective on the activity of gastric secretions in rats and also the action of the smooth muscles in the stomach and small intestine (Os'kina, et al, 1999).
Six compounds have been isolated from the seeds of Arctium lappa. Five if these have been known previously and include daucosterol (I), arctigenin (II), arctiin (III), matairesinol (IV) and lappaol F (V). The sixth compound was a new lignan named neoarctin B (VI) that was determined via spectral analysis (Wang & Yang, 1993). Daucosterol, matairesinol and lappaol F are all derivatives of the organic compound phenol.
Arctiin has been found to be stable in rat gastric juice, but change rapidly over to arctigenin in rat intestinal flora, followed by conversion to the major metabolite 2-(3",4"-dihydroxybenzyl)-3-(3',4'-dimethoxybenyzl)-butyrolactone. The metabolic process of arctiin shows that it first cleaves at the glycosidic bond and then demethylation of the phenolic methoxy group in the alimentary tract follows (Nose, et al, 1992). Artiin has also been found to have protective effects on PhIP (2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine)-induced carcinogenesis particularly in the mammary gland in the promotion period by testing on Sprague-Dawley rats. In contrast though, arctiin may have a week co-carcinogenic influence on MeIQx (2-amino-3, 8-dimethylimidazo [4,5-f] quinozaline) -induced hepatocarcinogenesis on male rats. Further more, the results of these tests suggest that PhIP is a weak pancreatic carcinogen in female Sprague-Dawley rats by targeting acinar cells (Hirose, et al, 2000).
Another component in A. lappa, desmutagenic fiber, was isolated and discovered to be a factor for reducing the mutagenicity of mutagens that are active without metabolic activation. An example of this would be mutagens such as ethidium bromide, 2-aminoanthracene, Trp-P-2, and Trp-P-1. The factor is resistant to heat and proteolytic enzymes and sensitive to treatment with MnCl2. The mutagen was irreversibly decreased when treated with the burdock factor (Morita, et al, 1984).
A dietary fiber comprised mostly of Arctium lappa, along with other fibers from various plants, has been found to prevent growth retardation in rats caused by mineral oil ingestion. A dietary fiber is the remnants of plant cell walls that are resistant to digestion by the alimentary enzymes of man, and is comprised of various polysaccharides and lignins. The inclusion of 8% mineral oil in a fat-free diet caused severe growth retardation in rats due to the reduction in nutrient intake and not to the evolution of essential fatty acid deficiency. The lack of nutrients being absorbed in the lumen of the intestine due to the mineral oil uptake prompted a decrease in nutrition to the body resulting in the retardation. The ability of the A. lappa to prevent the retardations can be attributed to it's ability to prevent the absorption of mineral oil in the intestinal lumen (Morita, 1993). Dietary fiber of A. lappa has also been found to improve growth and protection against toxins, such as amaranth in rats. Also, it was determined that the effectiveness of the fiber as a protective agent depends upon the physical properties such as settling volume in water and water-holding capacity (Takeda &Kiriyama, 1979).
Arctium lappa effects on anti-inflammatory and free radical scavenger activity was investigated by subcutaneous administering a crude extract of the plant. The studies showed that the crude extract significantly decreased carrageenan-induced rat paw edema, reducing the inflammation. Also, when simultaneously treated with carbon tetrachloride (CCl4), it produced activities that worked against CCl4-induced acute liver damage (Lin, et al, 1996).
Experimentation of Arctium lappa was assessed in several different tissue cultures for anti-HIV activity and for cytotoxicity in the body. A. lappa has been found to inhibit the activity of HIV and have a fairly low cytotoxicity level (anonymous, 1989; Yao, et al, 1992).
Lignins in A. lappa have been shown to inhibit the binding of platelet activating factor to rabbit platelets (Iwakami, et al, 1992). The significance of this is that A. lappa can act as an anti coagulant and prevent clotting. Medically this could be used as blood thinner for stroke and heart attack victims.
The medical significance of A. lappa is still not fully understood yet. Research is continuing on its applications as an anti-coagulant, AIDS treatment, and as an anti-ulcer treatment. Historically and presently the burdock has a notable rule in our medical world. Though other species of Arctium are used and being researched for other new medical uses, the most significant species is the A. lappa.
