Plants belladonna

Geriatric Considerations - Summary Alkaloids from the belladonna plant contain 3 potent anticholinergics and offer no advantage over other available drugs. Belladonna alkaloids possess potent anticholinergic effects and can cause dry mouth, blurred vision, delirium, confusion, psychosis, and increased risk of falls. This compound has no role in treating the older adult. 

Naturally occurring compounds are usually single enantiomers, e.g. L-morphine, L-hyoscine. Atropine is an exception. Although synthesised in the belladonna plant as L-atropine, it is partly converted in the extraction process to the D isomer (chiral inversion), and is administered as a racemic mixture. During this process its OCHF,... 

All parts of the belladonna plant contain the alkaloids. Linne named the species after one of the Fates, Atropos, who cut the thread of life. In Italy during the Middle Ages an extract of the plant was dropped onto the eyes in order to dilate the pupils (this practice gave rise to the name "belladonna" or beautiful lady since large dark pupils were considered a mark of beauty). Today atropine analogues, such as homatropine, are still used to dilate the pupils for opthalmalogical studies. Sympathomimetics can also be used for this purpose. See the Aside on Eye Openers . 

Atropine, a naturally occurring alkaloid, was first isolated from the belladonna plant, belladonna, in its pure... 

Atropa belladonna plants have been transformed with an H6H clone from H. niger. A. belladonna normally produces high levels of hyoscyamine, the precursor for the more pharmaceutically valuable alkaloid scopolamine (Fig. 3b). However, after transformation with the H6H gene, transgenic A. belladonna plants were shown to accumulate scopolamine almost exclusively (164). Additionally, the levels of tropane alkaloid production in a variety of hairy root cultures were altered by overexpression of methyltransferase putrescine-N-methyltransferase and H6H. Overexpression of both of these enzymes in a hairy root cell culture resulted in significant increases in scopolamine production (164, 165). Fluorinated phenyllactic acid substrates... 

Production of diploid and haploid transgenic Atropa belladonna plants... 

This study also shows that the existence of additional genes such as gus and npt II genes does not affect the morphological traits of the transgenic A. belladonna plants, which we obtained using the binary vector system A. rhizogenes RIOOO + pBI 121). 

Atropine is the racemic mixture of l- and o-hyoscya-mine and possesses 50% of the antimuscarinic potency of L-hyoscyamine. Atropine is derived from components of the Belladonna plant and is also present in other plants from the Solanaceae family. Women in ancient times often dripped the plant s juices into their eyes, causing mydriasis and thereby enhancing their beauty. In Italian, Belladonna translates to beautiful lady . In the United States, the atropine autoinjector has been in use since 1973 for the treatment of exposures to chemical warfare nerve agents and insecticides. 

Atropine was discovered in 1831 in the roots of the belladonna plant, and is a strongly poisonous alkaloid. Its chief use in medicine depends upon its action in dilating the pupil and paralysing the accommodation of the eye, and it is also used to check the inhibition of the heart arising from administration of chloroform and the depressant action of morphine on the respiratory centre. 

Hartmann Th et al.. Reinvestigation of the alkaloid composition of Atropa belladonna plants, roots cultures and eell suspension. In PM 53 390-395. Ml986. 

Pupillary dilation, not constriction, is a characteristic atropine effect, as indicated by the origin of the name belladonna ( beautiful lady ) from the ancient cosmetic use of extracts of the At-ropa belladonna plant to dilate the pupils. The answer is (B). 

The prosecutors wanted to prove that one can reverse the pinpointing effect that morphine has on the pupils of the eye by using atropine, which is found in the belladonna plant. 

Two well-known alkaloids, cocaine (3.11) and atropine (3.12), are ester derivatives of the 8-azabicyclo[3.2.1]octane ring system. Cocaine, isolated from a variety of the poppy plant, has been used as a topical anesthetic, but it is highly addictive if it enters the bloodstream and is now a controlled substance. Atropine, however, is highly useful in medicine with anticholinergic properties. It is isolated from the Belladonna plant and has been used for many years to dilate the pupil of the eye. It is also an effective antidote to poisoning by anticholinesterase chemicals, when these are used as insecticides or in extremely toxic form as chemical warfare agents. 

The use of undifferentiated cultures proved to be unsuccessful for tropane alkaloids production. These alkaloids are produced in normal and transformed roots [42, 51]. Several lines of evidence suggest that the differentiation of the tissue is necessary for the synthesis of these metabolites [42, 51]. Different studies suggest that this is probably related to the localization of key biosynthetic enzymes [6]. Among them, Suzuki et al. [52, 53] demonstrated that the h6h and pmt genes were expressed specifically in root pericycle of Atropa belladonna plants. In addition, Nakajima et al. [54, 55] pointed out that Tropinone reductase enzymes were accumulated in lateral roots of Hyoscyamus niger. 

On the other hand, Yun et al. [26] overexpressed the H6H in A. belladonna plants by A. tumefanciens transformation. In this case, leafs of the transformed plants accumulated almost entirely scopolamine [26],... 

In belladonna plants deuteration had a drastic effect on flower development (25). The number of calyx lobes, corolla lobes, and stamens, while invariably 5 in control flowers, increased to as many as 9 or 10 in plants grown in 70 percent D2O medium. Abnormally shaped berries formed in plants grown in heavy water. The extent of malformation depended,on the D2O content of the medium and how late in the life cycle of the plant that the berry formed. The shapes ranged from pear-shaped to dumbbell-shaped to cylindrical. The misshapened berries resulted from the tenacity with which the corolla remained attached to the ripening berry in deuterated plants. As the berry enlarged, a constriction developed where the corolla was attached to the berry. The size and number of seeds were severely reduced in deuterated berries with only a few rudimentary seeds apparent in the 70 percent berries. 

A replacement culture technique was developed by Crane et (27) to study the effect of deuteration on alkaloid production in Atropa belladonna. Plants were grown to maturity in an aqueoui (HoO) medivim and were then transplanted to media containing 50, 60, 75 and 99.7 percent D2O. The plants in 99.7 percent D2O showed the drastic effects of deuteration almost immediately and all plants died in several days. Plants transplanted into 75 percent D2O survived about 3 weeks, and the 50 and 60 percent D2O plants withstood the stresses imposed by deuteriiam. These plants were harvested after a growth period of 7.5 months. Alkaloid production was reduced to from one-third to one-tenth that of the control plants. The absolute amount of alkaloid formed and the total amount of plant material produced were too small to permit isolation of alkaloid. It appeared from this study that alkaloid production was completely inhibited upon transfer of the plants from normal growth in H20 to the deuterated medium. 

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