Catalyzes the cleavage of beta-carotene at its central double bond (15,15') to yield two molecules of all-trans-retinal. Exhibits the highest activity for beta-carotene, followed by beta-cryptoxanthin, beta-apo-4'-carotenal, alpha-carotene, and gamma-carotene in decreasing order, but has no activity on beta-apo-8'-carotenal, beta-apo-12'-carotenal, lutein, zeaxanthin, or lycopene, suggesting that the presence of one unsubstituted beta-ionone ring in a substrate with a molecular weight greater than C35 seems to be essential for enzyme activity. all-trans-beta-carotene + O2 = 2 all-trans-retinal Binds 1 Fe(2+) ion per subunit. The kcat is 4.5-fold higher with beta-carotene than with beta-cryptoxanthin as substrate. Optimum pH is 8.0. Optimum temperature is 40 degrees Celsius. Above this temperature, the enzyme activity decreases significantly, exhibiting 66% of the maximum activity at 50 degrees Celsius. Below 40 degrees Celsius, the enzyme activity decreases with decreasing temperature, exhibiting 15% of the maximum activity at 25 degrees Celsius. The half-lives of the enzyme at 35, 40, 45, 50, and 55 degrees Celsius are 17.6, 15.0, 12.5, 6.1, and 1.5 hours, respectively. Homodimer. Could be used for high retinal production. Belongs to the Brp/Blh beta-carotene diooxygenase family.