Gruber knew all this, but he also knew that some lactobacilli, the bacteria used to make yogurt, naturally excrete just the left-handed version of lactic acid.

FORBES: Magazine Article

Walking through his lab a decade ago, he had an epiphany: He envisioned an entire process by which he could feed corn sugar to lactobacilli that would exude ideal, highly concentrated lactic acid.

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Mazmanian: Yeah, all the Lactobacilli and bifidobacteria species.

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