Yes, methylene blue can be used in many foods, as it in non-toxic to humans (though it can discolor urine).
Methylene blue was used by Italian actor and gourmand, Ugo Tognazzi for his risotto alla parmigiana (risotto blu). He added methylene blue to the standard ingredients (butter, onions, Parmesan cheese, and white wine), turning it into a rather striking "blue risotto."
iodine
No, it isn't
Blue green algae are procaryo and mostly unicellular and form a source of food for other organisms. i.e, why blue green algae are called primitive organisms.
Maine lobsters are considered one of the food delicacies in the United States. Other delicacies in the US include blue crab from Maryland, and Morel mushrooms.
Keystone species of the Chesapeake Bay food web.
iodine
Methylene blue reduction is the method used to measure the bacterial density in milk. The test is evaluated in term of the amount of time required from introduction of the blue until the milk turns white.
The different colors come from different chemical compounds, so yes, there is a difference other than color.
food additives sugar
leafy green vegtables
Methylene blue stains both the nucleus and the cytoplasm of eukaryotic cells. The nucleus typically stains a deeper color. Its purpose is to make cells show up against their background. Methylene blue is also used to stain DNA or RNA after electrophoresis. It can be purchased at most aquarium shops for under 10 dollars. In some cases food dye might be suitable.
Jackie Chan and Bruce lee.
Food coloring, and other dyes.
Food coloring, and other dyes.
King of Africa Top of the food chain
to allow people to do other work besides farming.
I assume it is in most other places besides China but not so much in China.