It's interesting where the internet will take you... I started out today wanting to write a blog entry about a picture I took of what I thought to be belladona, or deadly nightshade, growing in a hedge on campus, and then to talk about how cool belladonna is.
However, I looked at my pictures, and then at the entry for Deadly Nightshade (a.k.a. Atropa Belladonna) on Wikipedia, and the flowers and the berries look a little bit different than this poisonous plant.
It turns out that this plant is actually Bittersweet Nightshade (a.k.a. Solanum Dulcamara), which is in the same family as belladonna, but not nearly as poisonous. I still wouldn't eat it. In fact, it's an invasive plant in this area, so I should probably have ripped it out, but the berries and flowers are so cute! Of course, I had to read about it on wikipedia for another half-hour...
Anyway, I have a few reasons to be interested in nightshade, one of which is that the Deadly Nightshade sleeves I knit a couple of months ago are based on that plant. Another is that nightshade is in the same family as tomatoes, potatoes, peppers, and eggplants. The main toxin in bittersweet nightshade is solanine, which is present in small amounts in all of these, I think, especially potatoes that have been exposed to light for too long.
I'm fairly allergic to eggplants. When I eat enough of them, I get a stomach ache and a sore throat, and it feels like my airways are closing up, which, according to ehow, means I should go to the emergency room when I have a reaction. I'm not sure if it's the solanine in eggplant that makes me sick, but I've never had any problems with other members of the Solanum genus.
So this lead me to research eggplant allergies, which are apparently very rare, and this lead me to this article talking about a study performed in India on a guy who was allergic to eggplant... and then I got bored, played Mah Jong for a while and fell asleep.