Nicotinic Acid (Niacin, Vitamin B3) — 5g

Description

🧬 Nicotinic Acid (Niacin, Vitamin B3) — NAD⁺/NADP⁺ precursor included in MS, B5, and most TC media vitamins mix. Important for cellular redox reactions and energy metabolism in cultured plant cells.

💡 Role in TC

Nicotinic acid is converted to NAD⁺ and NADP⁺ — the central redox coenzymes involved in: glycolysis, TCA cycle, oxidative phosphorylation, fatty acid synthesis, and the NADPH-dependent antioxidant system. Exogenous nicotinic acid in medium supplements endogenous synthesis, particularly important in callus cultures where metabolic activity is high.

Standard inclusion: 0.5–5 mg/L in MS vitamins. Linsmaier & Skoog demonstrated that while not strictly essential (unlike thiamine), nicotinic acid improves callus quality at optimal concentrations.

💡 In Murashige & Skoog medium, the standard vitamin stock includes: thiamine (0.1 mg/L), nicotinic acid (0.5 mg/L), pyridoxine (0.5 mg/L), and myo-inositol (100 mg/L).