1000 µg = 1 mg = 0.001 g

Grapes 500 g**
protein 3 g
protein quality 24 %
fat 1 g
linolenic acid 180 mg
carbs 75 g
vitamin E activity 3 mg
total carotenes 165 mg
vitamin B1 220 µg
vitamin B2 120 µg
vitamin B3 1 mg
vitamin B5 300 µg
vitamin B6 350 µg
biotin 7 µg
folic acid 200 µg
vitamin C 21 mg
vitamin K 15 µg
calcium 90 mg
magnesium 46 mg
phosphorus 100 mg
potassium 1 g
sodium 10 mg
chloride 10 µg
iron 3 mg
zinc 250 µg
manganese 520 µg
copper 414 µg
nickel 40 µg
chromium 10 µg
fluoride 70 µg
iodide 4 µg
silicon 750 µg
selenium 8 µg

** Souci, Fachmann, Kraut;
Food Composition And Nutrition Tables
Medpharm Scientific Publishers Stuttgart