Tobacco contains an alkaloid called nicotine.

烟草含有一种叫做尼古物碱。

This is the chemical formula for what alkaloid?

这是什么物碱化学式？

The bitter alkaloid that has this formula is caffeine.

这种苦味物碱配方是咖啡因。

It was but for a moment, for the action of the alkaloid is rapid.

可是这一切只是一会儿功夫，因为那种物硷作用发挥很快。

Alkaloids have many functions and effects, but almost all a bitter in taste.

物碱有许多功能和作用，但几乎所有苦味。

That's an alkaloid—so it's in the same class of molecules as caffeine and nicotine.

那是一种物碱——与咖啡因和尼古属于同一类分子。

Now, from a chemical perspective, caffeine can be described as both a methylxanthine and an alkaloid.

从化学角度来看，咖啡因既可述为甲基黄嘌呤，也可述为物碱。

While alkaloids as a whole are a broader group of naturally occurring organic compounds, defined by having at least one nitrogen atom.

而物碱作为一个整体是一个更广泛自然存在有机化合物组，定义为至少有一个氮原子。

On top of this, alkaloids from the vine have been shown to induce apoptosis in mice melanoma cells and certain liver cancer cells in humans.

除此之外，卡皮木藤条物碱已证实能促进小鼠黑素瘤细胞和人类某些肝癌细胞凋亡。

It's native to India and Southeast Asia, and its bark contains a poison called brucine, but the real lethality comes from the trees round green-to-orange fruit which contains the alkaloid strychnine.

马钱子原产印度与东南亚，它树皮富含称为 Brucine 有毒物碱。但真正会死人部分是马钱子-圆圆，绿色到橙色果实含有有毒物碱：马钱子碱。

Like caffeine, theobromine is a type of alkaloid, which is a huge class of molecules that generally contain rings with at least one nitrogen atom in them, and alkaloids often have physiological effects on humans and other animals.

和咖啡因一样，可可碱属于物碱一种，物碱是相当大一类分子，一般来说它环中会包含至少一个氮原子，物碱通常会使人类及其他动物产理作用。

It's hard to know exactly why we evolved to be better at digesting theobromine, but it might be because alkaloids mostly come from plants, and our ancestors ate a lot more plants than early cats or dogs did.

我们很难确切了解为什么我们身体会进化成能较容易消化可可碱，有可能是因为物碱大部分都来自植物，而我们祖先吃植物比前猫和狗所吃植物多很多。