If you can't find ponzu sauce, you can substitute lemon juice. A tablespoon of lemon juice can replace a tablespoon of ponzu, and can work just as well. Just remember that lemon juice has an extremely acidic pH, so be careful when using it in this way, as it could overpower your entire dish. However, if you don't find lemons in your local supermarkets, you can substitute them with other flavors.
This website provides approximate nutrition information for convenience and as a courtesy only. Nutrition data is gathered primarily from the Spoonacular Database, whenever available, or otherwise other online calculators.