there are chemicals that help the bacteria grow.
Salt water slows the dehydration (browning of apples) because it is an acid.
Lemon juice helps slow down or prevent the oxidation of food, but I have heard little about preserving it. Peel an apple and dip it in acidulated water (water and lemon juice) and the apple won't turn brown (for a while).
A drug that slows your vision down and makes you hyper. A bunch of different chemicals
Browning is polyphenol oxidase (PPO) react with oxygen which form "Rust" Coating freshly cut apples in sugar can reduce oxygen diffusion and thus slow the browning reaction.
Yolk slows down cleavage. Those eggs that contain a lot of yolk in one end of the egg undergo meroblastic cleavage. Their blastulae contain both macromeres and micromeres.
Lemon juice does not have much effect on a catalyse enzme. If you were to measure it on a scale of 0 to 3 then it is more than likely going to be a zero or 1/2.
Drinking non-alcoholic drinks and consuming food while drinking alcohol slows the absorption of alcohol into the blood.
Your metabolism slows down, or to a halt. Your body starts eating at your muscle, not the fat. You contain the fat and lose only muscle.
there are no distinctions between chemicals and non-chemicals in the sense that all matter in universe are made up of atoms from the periodic table, but to answer your question in a less technical way an enzyme is better classified as a protein. please note also that chemicals as environmentalists and organic food promoters define it does not exist and everything is made of chemicals so phrases like "that apple has chemicals in it" is inane because the apple is made of chemicals. this doesn't make any sense.
peristalsis slows down the large intestante
When an object slows down it is still accelerating.
friction slows it down