Frankincense (Boswellia carterii) has many medicinal benefits. In Egypt, a few people like to use it in chewing and sometimes in incense. This study aimed to use the water extract of frankincense powder prepared by soaking in drinkable water for 24 hours (T1) and boiling in water for one hour (T2) for the fortification of guava nectar in concentrations ranging from 0.25 to 2% (volume/ volume (v/v)). The chemical composition, phenols, and flavonoids contents of the frankincense were determined. Anti-oxidant (DPPH method) and antimicrobials (pathogenic bacteria) and cytotoxicity (HepG-2 and MCF-7 human cancer cell lines) activities were measured. Sensory evaluation and the physical properties of the guava nectar mixed with water extracts of frankincense were evaluated. The phenols and total flavonoid contents of the T2 sample were 0.869 and 0.147 mg/g, respectively. However, it was 0.748 and 0.070 mg/g, respectively for T1. The results showed that frankincense powder has 93.74% antioxidant activity with 67.26 mg/ml IC50. The results also showed that the T2 sample has antibacterial activity against Salmonella typhi and Bacillus cereus. The results also showed that the frankincense powder has cytotoxic activity and this activity is strong on HepG-2 human cancer cell lines compared to the positive control (doxorubicin), however, it is less activity on the human breast adenocarcinoma (MCF-7). The IC50 values of the frankincense powder were 7.8 and 33.9 µM, respectively, while doxorubicin values were 10.3 and 28.5 µM, respectively. The results of the sensory evaluation showed that water extracts of the frankincense can be added to guava nectar at concentrations up to1%.
It can be concluded that it is possible to mix aqueous extracts of the frankincense with guava nectar to obtain a product with a pleasant taste, color, and aroma and having also the advantages of frankincense.