Journal Article

The Effect of Water Stress on Bioactive Compounds in Australian-Grown Black Sesame

Mani, Janice S., Trotter, Tieneke, Batley, Ryan J., Bhattarai, Surya P., Johnson, Joel B., Hoyos, Beatriz E., Naiker, Mani

2024

Overview

Sesame is an emerging crop of interest in Australia and has attracted widespread interest due to the health-benefitting properties of its bioactive compounds, including fatty acids, lignans, and polyphenols. This study aimed to investigate the impact of drought stress on these bioactive compounds, using eleven cultivars of black sesame seeds grown in Australia. Specific varieties responded positively to water deficit (WD) conditions, showing increased levels of TPC, FRAP, CUPRAC, and lignans. Varieties 1, 4, 7, and 12 showed significantly increased FRAP values ranging from 158.02 ± 10.43 to 195.22 ± 9.63 mg TE/100 g DW in the WD treatment compared to the well-watered (WW) treatment, whereas varieties 7, 10, 12, 13, and 18 demonstrated the highest CUPRAC values of all varieties (2584.86 ± 99.68–2969.56 ± 159.72 mg TE/100 g) across both WW and WD conditions, with no significant variations between irrigation regimes. Moreover, lignan contents (sesamin and sesamolin) were higher in varieties 1, 2, 5, and 8 grown in WD conditions. Compared to the optimal unsaturated to saturated fatty acid ratio (Σ UFA/Σ SFA ratio) of 0.45, all sesame genotypes showed superior ratios (ranging between 1.86 and 2.34). Moreover, the ω-6/ω-3 PUFA ratio varied from 33.7–65.5, with lower ratios in varieties 2, 4, 5, 8, and 18 under WD conditions. The high levels of phenolic compounds and healthy fats suggest the potential of black sesame to be incorporated into diets as a functional food. Furthermore, the enhanced phytochemistry of these cultivars in WD conditions is promising for widespread adoption. However, larger trial studies to confirm these findings across different geographic locations and seasons are warranted.

• Publisher: MDPI AG,MDPI
• Subject: antioxidant activity / Antioxidants / Aquatic resources / Australia / Bioactive compounds / Biological activity / Comparative analysis / Crop diseases / Cultivars / cupric ion-reducing antioxidant capacity / Drought / Droughts / Environmental aspects / Environmental impact / fatty acid composition / Fatty acids / ferric-reducing antioxidant power / Forecasts and trends / functional foods / Functional foods & nutraceuticals / Genotypes / Geographical locations / International economic relations / Iran / Irrigation / Lignans / Moisture content / Netherlands / Nutritional aspects / Oilseeds / Phenolic compounds / Phenols / Physiological aspects / phytochemicals / plant biochemistry / Polyphenols / Polyunsaturated fatty acids / saturated fatty acids / Scientific equipment and supplies industry / Seeds / Sesame / Sesamum / United States / Water deficit / Water stress