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This study investigates the antioxidant components (total carotenoids, lycopene, β-carotene, total phenols, flavonoids, ascorbic acid and total vitamin C) as well as the hydrophilic and lipophilic antioxidant activities (HAA and LAA) of tomato genotypes consisting of one ordinary cultivar Rio Grande and the two high-lycopene breeding lines HLT-F71 and HLT-F72. The correlation of nutritional value to L∗, a∗, b∗ colour indexes and a∗/b∗ ratio was also investigated in whole and fresh cut tomato fruits. Except for β-carotene content, significant differences were found among cultivars for antioxidants. The berries of both HLT-lines recorded higher antioxidant contents, HAA and LAA (TEAC and FRAP assays) than Rio Grande. Under controlled conditions, HLT-F72 reached the highest levels of total carotenoids (165.5 mg β-ca Eq per kg fw), lycopene (150.1 mg per kg fw) and total phenolics (549.7 mg GAE per kg fw). However, HLT-F72 exhibited the highest levels of ascorbic acid (193.3 mg per kg fw), total vitamin C (271.6 mg per kg fw) and flavonoids (450.5 mg RE per kg fw). Line HLT-F71 showed the highest HAA (148.0 µM Trolox per 100 g fw and 4.2 mM FRAP per g fw) and LAA values (258.5 µM Trolox per 100 g fw and 3.2 mM FRAP per g fw respectively). Colour readings in red ripe fresh cut tomato berries particularly a∗, b∗ and the ratio a∗/b∗ could represent an indicator not only for lycopene but also for other phytochemicals and resulting antioxidant activities. HLT-Lines may serve as a starting point for the development of semi-determinate growth habit tomato cultivars with higher functional quality.

Pyrogallol, as an important chemical raw material and reagent, has been prepared by the decarboxylation reaction of gallic acid hydrolyzing tannin acid extracted from Chinese gall, but the decarboxylation reaction is known to cause serious environmental pollution. To obtain efficient strains to degrade gallic acid, a screening study was carried out to explore different strains and optimal fermentation conditions of single impact factors, as well as using response surface methodology. The antioxidant bioactivity of products containing pyrogallol in the fermentation medium was also estimated. The results indicated that Enterobacter aerogenes could degrade gallic acid into pyrogallol with 77.86% average yield under the optimal fermentation conditions of an inoculum size of 5%, substrate concentration of 0.32%, incubation period of 60 h, fermentation temperature of 32 °C, content of phosphate buffer at 25%, and an initial pH of 6.0 in fermentation medium. The products contained 66.5% pyrogallol and were tested for their antioxidant capacity. They proved to have stronger antioxidant capacity compared with ABTS, BHT, and even Vc. In conclusion, the study provided a simple, highly efficient method, superior to complex genetic engineering technologies, to degrade gallic acid into pyrogallol, suggesting the possibility of large-scale production in the future.