Chew five leaves of this plant every morning. It’s the most effective natural mouth freshener. You can also put your mouth closer to holy basil plant and breath for five minutes. This Process will Improve Your Lung Function. Remember that pure oxygen coming out of holy basil kills the bacteria. If you can’t find this plant in your local nursery, then buy its seeds online and grow it in your garden. If you want to grow it indoors, use a strong grow light.