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  • Hi. It's Mr. Andersen and in this podcast I'm going to talk about lipids

    嗨,我是安德森。 在這集播客當中,我將談論有關「脂質」,

  • or the fats. The fat that's found in butter or the fat that's found in olive oil is what

    俗稱脂肪。 那些存在於奶油、橄欖油當中的脂肪,

  • we call a triglyceride. It's basically going to have a head, a glycerol head and then it'g

    我們稱之「三酸甘油酯」。它的基本組成為一個甘油分子的頭端,

  • going to have three fatty acids tails. And that's where the energy is. And so when we

    以及三個脂肪酸分子的尾端--此即能量所在。 因此當我們攝取脂肪,

  • eat fat we can break it down. We have enzymes called lipases that are able to break that

    體內有種稱為「脂酶」的酵素,能夠把它分解下來,

  • down and then we can get energy from it. And that's been very important. We can store energy

    人體便可從中獲取能量。這是非常重要的:我們可以把能量儲存在

  • in fats inside our body and then we can burn them when we need them. But don't forget that

    體內的脂肪,當我們需要的時候,再燃燒它汲取能量。 但是別忘記,

  • fats in addition to providing energy also provide the surroundings. And so the cell

    除了提供能量,脂肪也提供了......遮蔽的功能,

  • membrane that goes around every cell is made up of phospholipids. And the cholesterol is

    那些環繞著每一個細胞的膜,都是由「磷脂質」所構成。

  • found within the phospholipid by layer and that maintains the fluidity of the cell. And

    而磷脂雙層內發現的「膽固醇」則維持了細胞的流動性。由此看來,

  • so lipids are incredibly important. But where does the energy come from? That comes from

    脂質的重要性是不言而喻的。 那麼,能量又是從何而來?脂質的能量源自於

  • the hydrocarbons. And so if you look at those fatty acid tails it's essentially a carbon

    「碳氫化合物」。如果你觀察這些脂肪酸的尾端, 它本質上是一個碳原子

  • attached to a carbon to a carbon to a carbon to a carbon . . . and then it has hydrogen

    連接到另一個碳原子,連接到另一個碳原子(x24次)......以及

  • around the outside of it. And so we call that a hydrocarbon. And there's energy in those

    在碳鏈外的氫原子所組成,故名「碳氫化合物」。 能量便存在於這些鍵結當中。

  • bonds. And so gasoline burning out of control or the paraffin wax that's burning in a candle

    無論是劇烈燃燒的汽油,或燃燒石蠟的蠟燭

  • is a hydrocarbon. There's a lot of energy between those carbon hydrogen bonds. And so

    皆為碳氫化合物。這些碳氫鍵之間存在著的很多能量。

  • there's also a lot of energy found in butter or in olive oil. It's in the bonds between

    奶油或橄欖油當中的碳氫化合物亦然--能量存乎於

  • the carbon and the hydrogen. And so let's start with a triglyceride. So this is a basic

    碳和氫之間的鍵結當中。 讓我們從三酸甘油酯開始,這是一個基本的脂肪。

  • fat. The head up here is going to be called the glycerol head and then this is going to

    分子的頭部,這部份被稱為甘油頭端,而另一邊

  • be the fatty acid tails that go down the end. And so fatty acid tail has so much carbon

    則是一路延伸到底的脂肪酸尾端。 我們可以看到,脂肪酸尾端的碳氫原子數目

  • and hydrogen in it that on this diagram we don't even draw them. Each of these points

    是如此之多,多到這張圖甚至不把它們詳示。 這些長鏈中的每一個的點

  • represents a carbon, a carbon, a carbon. And then right here we're going to have two hydrogen

    皆代表一個個的碳原子。而在這長碳鏈附近,

  • bonds or two hydrogens bonded to each of those carbons. And so you can see that there's a

    每個碳原子還會被兩個氫原子鍵結。由此可見,

  • huge amount of energy locked within that triglyceride and we can get that out through cellular respiration.

    大量的能量被封存在這一分子的三酸甘油酯當中, 而藉由細胞呼吸作用,我們得以汲取這些能量。

  • But know this. Those tails can come in two different forms. We can have what are called

    請注意,這些尾巴可能存在兩種不同的形式。

  • saturated tails. A saturated tail is going to have hydrogen all the way around the outside.

    一種可能是脂肪酸為飽和狀態, 飽和脂肪酸上的氫原子佈滿了碳鏈的周圍。

  • And if you have hydrogen all the way around the outside then you're going to be saturated

    想像如果你被一堆氫原子所包圍,

  • with hydrogen. And if you're a saturated fat you're going to be a straight fat. And so

    那麼你便被這些氫原子所「飽和」。 而如果你是個飽和脂肪,那麼你將會是直鏈的脂肪。

  • a triglyceride is going to have three of these fatty acid tails and the glycerol head, but

    所以三酸甘油酯分子 會有三個這些脂肪酸的尾巴,一個頭端的甘油,

  • if it is saturated all of those are going to be straight. And if they're all straight

    如果它們都是飽和的,那麼三條尾巴都將會是直鏈的。 而如果它們都是直鏈的,

  • they can pack up on top of other triglycerides. And so saturated fats are normally going to

    這些尾巴便能夠,與其他的三酸甘油酯擠在一起。 因此,飽和脂肪通常

  • be a solid at room temperature. What happens if you don't have hydrogen all the way around

    在室溫下是固體。而如果你尾巴的碳鏈 並沒有完全被氫原子所包埋,會發生什麼事呢?

  • the outside? You're going to form these double bonds in here. If you have double bonds basically

    這種情況下,碳鏈將會形成雙鍵,像這裡畫的。

  • what that does is it puts a bend in your tail. And so you're going to have a kinky tail.

    雙鍵基本上會在你脂肪酸的碳鏈上,造成一個扭折, 你將會有一個彎折的尾巴。

  • And so if you're a saturated fat, you're going to look like this. If you're an unsaturated

    如果你是一個飽和脂肪,你看起來會像這樣。 如果你是一個不飽和脂肪

  • fat you're going to look like this with kinky tails. And the kinky tails can't quite pack

    你看起來則會像的這樣--有彎折的尾巴。 而這些彎折的尾巴不太能夠擠在一起。

  • together. And so normally fats that are unsaturated are going to be a liquid at room temperature.

    因此,通常不飽和的脂肪在室溫下會是液體。

  • Now humans have figured out how to take, for example, vegetable oil, which is a unsaturated

    現今,人類已經理解如何能夠把,舉例來說, 植物油,一種不飽和脂肪,

  • fat or it's going to be a liquid at room temperature and we can bubble hydrogen through it. We

    或者其它任何在室溫下為液體的脂肪, 通以氫氣氣泡,

  • can straighten out those tails and we can make a saturated fat called margarine that's

    使它們的尾巴變成直鏈,人為地製造出飽和脂肪, 也就是「人造奶油」,

  • going to be a solid at room temperature. We've transformed this fat and if you know anything

    而它在室溫下將會是固體--我們改造了這個脂肪! 如果你對所謂脂肪稍有認識的話,

  • about fats those saturated fats are the ones that are least best for us and can lead to

    那些飽和脂肪,這類對我們身體最不好的脂肪,

  • arteriolosclerosis, especially trans fats. Example then of how we've tried to get around

    會導致小動脉硬化,特別是反式脂肪。 有個例子展示了我們如何試圖克服

  • this. And this is a somewhat funny story. This is olestra. Olestra is a fat that was

    這個缺點,這是個滿有趣的故事: Olestra 是一種由人造的脂肪,

  • made by humans. And so basically what they did us took a normal triglyceride but they

    基本上,人類所動的手腳是, 他們把尋常的三酸甘油酯分子,

  • built it around a sucrose, so they built it around a sugar. And so instead of having just

    接到一蔗糖分子的周圍,製造了一個由脂質環繞的糖。 不同於尋常的三酸甘油酯,

  • three of these fatty acid tails they had sometimes eight, sometimes ten. Sometimes even more.

    其尾巴不會只有三條, 它們可能有八條、十條,有時甚至更多。

  • What's neat about that is that when you go through your digestive system we don't have

    這個分子特別的是,在消化系統中,我們並沒有

  • olestrase. We don't have an enzyme that can break that down and so the olestra moves right

    所謂的「olestrase」。 我們沒有任何酵素可以分解它,所以 olestra 便持續

  • through our digestive system. So it's a fat that feels like a fat, tastes like a fat but

    完好無缺地通過我們的消化系統。因此, 它算是一種看起來像脂肪,嚐起來像脂肪,

  • it doesn't make us fat. And so Wow chips were introduced I think in the 1990s and had this

    但卻不會使我們發胖的脂肪。 我記得,大約在九零年代問世的 Wow 洋芋片,其成分

  • olestra in it. Basically what happened is when people started eating these Wow chips,

    就含有 olestra 然而吃了這些洋芋片的人,

  • they got incredibly sick. They got cramping and they had to put a warning label on the

    卻生了嚴重的病。除了痙攣, 他們甚至在包裝外標記了警語表示

  • outside that it can lead to loose stools, and it pulls vitamins outside of your body.

    它可能導致脂肪痢,還會造成維生素從體內流失。

  • They've kind of refined this since then and so there's not a lot of these adverse reactions.

    之後,他們已稍加精鍊含有此成分的產品, 於是現在便較少聽到,食用後發生的這些不良反應。

  • I think Pringles light chips still contain olestra in it, but we're tricking our body,

    我想,品客洋芋片現在仍含有 olestra 但實際上我們在欺騙我們的身體,

  • because our body doesn't have those enzymes. Now I also said there are two more important

    因為我們的身體並沒有分解它的酵素。 剛才我也提及了另外兩種比較重要的脂質

  • lipids. The first one's called phospholipids. Phospholipids are going to have, you can see,

    第一種稱為磷脂質。 磷脂質的分子具有,你可以看到,

  • two fatty acid tails, but they're going to have a head that contains a phosphate group.

    兩個脂肪酸的尾巴, 除此之外,還具有一個含磷酸基團頭端。

  • That phosphate group is going to have a negative charge. And so normally if we were to pour

    這個磷酸基團帶有一個負電荷。因此一般而言,

  • oil into water it's going to separate. And the reason why is that fats are non polar.

    如果我們把油倒入水中,它們會分開。因為脂肪是非極性的,

  • They don't have a charge. But what's neat about phospholipids is that they have a head

    它們並不具有電荷。但對磷脂質而言有趣的是,他們有個

  • that is going to have a negative charge and then they have the tails that are uncharged.

    帶有一個負電荷的頭端,以及不帶電的尾端。

  • And so if you just throw a bunch of phospholipids in water they'll form these spheres, micelles,

    所以,如果你若是把一堆的磷脂質倒進水中, 他們將會形成這些球狀物、微胞,

  • or they'll form these spontaneous membranes. And so the cell membranes of all cells are

    又或者他們會自發性地形成這些膜。所以說,所有細胞的細胞膜

  • made up of phospholipids. And so bacteria, archaea, eukarya, plants, animals, fungi,

    皆是由磷脂質所構成。 諸如細菌,古細菌,真核生物,植物,動物,真菌......

  • we all have cell membranes. And those membranes are made up of phospholipids. They regulate

    皆擁有細胞膜。而這些膜都是由磷脂質構成的。他們調節了

  • what gets in and out a cell. Cholesterol is going to maintain the fluidity of the membrane.

    哪些物質能夠進出細胞。 膽固醇則是要保持膜的流動性,

  • And so this cell membrane right here is made up of phospholipids. Those phospholipids are

    這兒看到的是磷脂質組成的細胞膜。這些磷脂質會

  • constantly moving back and forth and that's important because it allows things like oxygen

    不斷地來回運動,這點非常重要,因為這使得氧氣能夠進入

  • to get in and carbon dioxide to get out. But if the cell gets heated up those phospholipids

    二氧化碳能夠離開。 但是,如果細胞處在溫度高的狀態,

  • tend to fall apart. And if it get's really cold they'll crowd together and so the function

    這些磷脂質會傾向分崩離析。 而如果溫度過低,他們則會聚集在一起,

  • of cholesterol is to grab onto those fatty acid tails and hold them together when it

    因此膽固醇的功能,乃在於抓住這些脂肪酸的尾巴,

  • gets too cold but keep them apart . . . or hold them together when they get to warm and

    溫度過高的時候,將他們約束在一起;

  • keep them apart when they get too cold. And so cholesterol is important at maintaining

    溫度過低的時候,則讓他們彼此維持距離。 所以說膽固醇的重要性,在於保持

  • that integrity of the cell membrane. And you can see cholesterol in this diagram right

    細胞膜的完整性。在這個圖示當中, 你也可以看到在這兒的膽固醇分子。

  • here. We can build it in each of our cells and we have to build it in our cells, but

    體內的每個細胞都能夠製造膽固醇, 實際上我們也必須製造它,

  • we have to get a little bit of it in our diet. And so we need lipids in our diet. If we don't

    但從食物當中,我們仍需攝取少量的膽固醇。 脂質是我們飲食所必需的。如果我們缺乏脂質

  • have lipids we can't get energy and more importantly we can't make our cell membranes. However,

    我們便不能從中得到能量, 更重要的是,我們將無法製造的細胞膜。然而,

  • today everybody's getting the fat they need. This is my favorite place to eat when I go

    當今,大家攝取脂肪的都已足夠。 這是我去加州的時候

  • to California because we don't have them in Montana. This is In-N-Out burger. I love the

    最喜歡去用餐的地方,因為我住的蒙大拿州,境內並沒有這家店。 這個地方是 In-N-Out burger,

  • taste of a big burger from In-N-Out. The lipids are great but there's probably too much trans

    我超喜歡 In-N-Out 大漢堡的味道-- 脂質是真的很不錯,但其中可能含有太多的反式脂肪。

  • fats in there. It's not good for me and could lead to heart disease. But for now I'm going

    這是對我並不好,可能會導致心臟疾病。不過目前我還是會繼續享用。

  • to keep eating them. So that's lipids, that's fat and I hope that was helpful.

    以上是脂質的介紹,希望對各位有所幫助。

Hi. It's Mr. Andersen and in this podcast I'm going to talk about lipids

嗨,我是安德森。 在這集播客當中,我將談論有關「脂質」,

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