Cactus pears (Opuntia ficus-indica) are draught resistant plants originated in Mexico. Their flattened stem segments, called cladodes, have moisture, protein and fibre contents of 92, 1-2 and 4-6% respectively, and a pectin content in the range of 0.8-3.3% depending on the species. They also contain certain concentration of carotenoids which are of special interest because of their antioxidant activity. This work is aimed to identify and quantify the main carotenoids present in the stems and to evaluate the effect of thermal treatments on the antioxidant activity and concentration of carotenoids and phenolic compounds. The carotenoids -cryptoxanthin, -carotene and lutein were identified in the cladodes, the latter having the highest concentration. Thermal treatments increased the extractability of these pigments and the antioxidant activity was related to the carotenoids concentration. Total phenolic content decreased after the thermal treatments; however this result had little effect on the antioxidant activity. Mucilage present in the stems decreased the extractability of the carotenoids.

Carotenoids extracted from dried peppers were evaluated for their antioxidant, analgesic, and anti-inflammatory activities. Peppers had a substantial carotenoid content: guajillo3406±4 μg/g, pasilla2933±1 μg/g, and ancho1437±6 μg/g of sample in dry weight basis. A complex mixture of carotenoids was discovered in each pepper extract. The TLC analysis revealed the presence of chlorophylls in the pigment extract from pasilla and ancho peppers. Guajillo pepper carotenoid extracts exhibited good antioxidant activity and had the best scavenging capacity for the DPPH⁺cation (24.2%). They also exhibited significant peripheral analgesic activity at 5, 20, and 80 mg/kg and induced central analgesia at 80 mg/kg. The results suggest that the carotenoids in dried guajillo peppers have significant analgesic and anti-inflammatory benefits and could be useful for pain and inflammation relief.