Lemon juice, over time or if in big enough doses, could lighten the color of your skin. Be careful when applying it or else you'll have discolored patches of skin.
Also, rubbing alcohol kills acne better than any over-the-counter medicine. Rubbing alcohol dries out pores. You must be careful when applying it as well. But if you apply rubbing alcohol to your acne affected arounds and even around them to kill the roots, both day and night, then the majority of your acne problems should be gone in two to three weeks. It's a trick my grandmother passed down to my mother, who in turn passed it on down to me. Rubbing alcohol has helped so many people in my family win the fight against acne. You can buy rubbing alcohol for a dollar at the Dollar Store.
Hope this helps!