Plants endue a key role against illnesses caused by oxidative stress. These attributes are frequently associated with polyphenolic compounds. However, presence and concentration of secondary metabolites are affected by abiotic factors. The in vitro culture techniques can solve these drawbacks. Peppers can be a suitable alternative to obtain polyphenols. Aiming to optimise the callus culture stage from Capsicum baccatum to produce polyphenols, this work evaluated systemically the effects of the explant's origin (root, hypocotyl and cotyledon), growth hormone type (2,4-dichlorophenoxyacetic acid (2,4-D), benzylaminopurine (BAP) and a combination of 2,4-D/BAP at five-to-one ratio) and concentration (0.023-10.000 mg L) on callus culture efficiency parameters using a multilevel factorial design. The root explant in combination with BAP at 1.138 mg L ensured the optimal values of the assessed responses; ​callus mass (225.03 mg), antioxidant activity (35.95%), total phenols (11.48 mg of GAE/g DE) and flavonoids (15.92 mg of RU/g DE) production.

The Capsicum genus comprises hundreds of varieties with fruits that differ widely in shape, size, color, and flavor. The Brazilian cuisine consumes Capsicum baccatum L. (pepper) extensively and few reports about chemical composition and biological properties about this pepper were published. The present study determined four factors numeric effects on germination in vitro of this specie, among them, the solution type for osmotic conditioning (water and 1% KNO3 aqueous solution), germination medium (agar and agar + gibberellic acid at 1.88 mgL -1 ), post-seeding time (15 and 30 days) and two genotypes (Pitanga and Cambuci) on two germination parameters (germination and cotyledon emerging rates), as first step for establishing a cell suspension culture to produce secondary metabolites. The methodology was a two-level full factorial experimental design (2 4 ). The results allowed polynomial equations definition which describes the germination phenomena as a function of the four factors under study. The genotype responses to osmotic conditioning and germination medium were different. The optimal combination of treatments for in vitro germination and development of seedlings for Pitanga and Cambuci was water + agar and water + agar-GA3, respectively.