Germs need an alkaline environment in which to thrive and multiply, making lemon juice a natural enemy due to its rich acid content. One oz. of pure lemon juice contains 1.44 g of citric acid.

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California and Arizona produce almost all the lemons consumed annually in the U.S.

Expert Insight

Lab studies support the effectiveness of lemon juice as an antibacterial. The Leptospirosis Information Center finds the citric acid in lemon juice a suitable substitute for chemical cleaners. Leptospirosis is a bacteria that can cause disease in animals and humans, and is not tolerant of acids.

Significance

In a 1993 test to determine the effectiveness of lemon juice in purifying water in Argentina, the National Center for Biotechnology Information reported a significant reduction in the v. cholera bacterium as long as enough lemon juice was used to lower the water's alkalinity levels, which encourage bacterial growth.

Potential

Because of its properties as a germ killer, lemon juice can serve as an effective and natural alternative to household disinfectants, as well as a natural freshener.