Evaluation of Some Phytochemical Characteristics of Berberis integerrima in Response to Nano-Zinc Foliar Application and Post-Harvest Drying Temperature

Abstract Background and Objectives Mineral nutrition and post-harvest handling are the major factors affecting secondary metabolites content and composition of plants. Berberis integerrima is one of the most important medicinal plants listed in all pharmacopeias. The bark, fruits and roots of this plant are commonly being used by traditional and modern medicine disciplines. They are well documented for their anti-diabetic, anti-cancer, and antimicrobial activities with berberine as the main active constituent. Also, the shrub has ornamental uses in the landscape and the fruit is used as a food additive. In addition, anthocyanin of the fruit is useful as a natural coloring agent in food industries. There are few studies on the agronomic demands and post-harvest handling of this plant. The experiment was conducted to assay the effects of nano-zinc foliar application and postharvest plant drying temperature on some phytochemical traits of this highly valuable plant.   Materials and Methods The treatments were applied to assay the phytochemicals content variations in roots, fruits and aerial parts of the plant (2 years old) by two separate experiments as factorial based on RBCD. In the first experiment, the effects of nano-zinc foliar spray on the yield, anthocyanin content, Zinc content and TSS at the different mentioned organs were studied. In the second experiment, the effects of diverse post drying temperatures (25, 50 and 750C) on total phenolics content, flanonoids content, hydrolysable tannin and berberin content in Berberis integerrima were assayed.   Results Zn content, TSS content and anthocyanins were affected by the independent effects of foliar spray and plant part. Plant dry weight was impacted by the organ type. Phenolics, flavonoids and alkaloids contents were affected by the interactional effects of the foliar spray , the organ type, and the drying temperature. The highest figure for the contents of alkaloids (30 mg g-1DWt) and flavonoids (26.9 mg g-1DWt) were from the root × foliar spray by 6 mgL-1 Nano-Zinc at 250C drying regime. The maximum amount of total phenolics was attained by the aerial parts × foliar spray by 6 mgL-1 Nano-Zinc at 250C and fruits × 3 and 6 mgL-1 foliar spray at 250C. For hydrolysable tannins (1.9%), the root and the aerial parts × 250C showed the largest figure. Discussion The overall results revealed the positive effects of nano-zinc foliar application on the studied gross secondary metabolites content in Berberis integerrima. The post-harvest drying temperature influenced the metabolites content as well, and the optimized temperature in the experiments was 250C.