Yields of β-haematin formed in the presence of individual constituent lipids of NLB vary with the identity of the lipid. High yields of about 60–80% were obtained with MPG at L/H ratios from 2.15 to 0.54 with a sharp decrease in yield to less than 10% below 0.27 L/H (A). MSG and DPG at 2.15 L/H gave lower yields of about 40%, which decrease sharply to about 10–20% at L/H ratios of 0.54 and 1.07 respectively (B and C). DLG gave high yields around 80–90% at higher mol ratios (2.15–0.54) which decreases sharply to about 40% at 0.27 L/H mol ratio and drops further to about 10% and lower at 0.13 L/H (D). DOG appears to be the most efficient lipid with a high yield of almost 90% between 2.15 L/H and 0.27 L/H before decreasing sharply between 0.27 and 0.13 L/H (E). Citric buffer (50 mM, pH 4.8), 37°C, incubated for 30 min. Constant total Fe(III)PPIX concentration of 30 μM. Error bars represent SEM (A, C – E, n = 3; B, n = 4).