Enhancing nutrient bioavailability by balancing antioxidant and antinutritional properties in organic tomatoes using Kappaphycus alvarezii based biostimulants

Organic farming has gained increasing attention for its sustainability and health benefits, particularly in crops like tomatoes, which are essential due to their high consumption and nutritional value.This study investigates the effects of Kappaphycus alvarezii (red seaweed) biostimulants on the nutritional composition, antioxidant content, mineral bioavailability, and antinutritional factors of organically grown tomatoes.This study evaluated the impact of cow urine extracted seaweed (SWC) at 10%, 5% and water extracted seaweed (SWW) at 10% biostimulants on fruit quality.Results revealed significant improvements in the proximate composition of tomatoes, with SWC 10% leading in moisture, protein, fiber, and carbohydrate content.Mineral nutrient analysis showed SWC 10% achieving higher levels of essential minerals like calcium (152.28 mg/100 g), magnesium (41.44 mg/100 g), potassium (563.21mg/ 100 g), iron (15.32 mg/100 g), and zinc (0.86 mg/100 g) compared to the control.The biostimulants also boosted antioxidants, particularly vitamin C, carotenoids, and lycopene, with SWC 10% outperforming other treatments.Additionally, SWC reduced antinutritional factors, such as phytates, oxalates, and tannins.Notably, SWC 10% reduced phytates to 98.36 mg/100 g from 129.47 mg/100 g in the control.Also, the mineral bioavailability was enhanced by keeping the phytate : Ca, phytate : Fe, phytate : Zn and phytate*Ca : Zn ratios below critical limits (0.24, 1.0, 18.0, and 200, respectively).Additionally, tomatoes treated with SWC 10% exhibited improved marketable qualities, including total soluble solids (6.76%), titrable acidity (0.59%), taste index (1.16), and fruit firmness (1.98 kgf/cm).The study highlights the potential of K. alvarezii derived biostimulants to enhance the nutritional and marketable qualities of organic tomatoes, contributing to improved human health outcomes besides promoting sustainable agriculture practices.