Changes in <i>Pleurotus ostreatus</i> nutritional value and heavy metal profile as a result of supplementation with nano-additive

Abstract

The present study evaluated the effect of Lithovit-Amino25 on the nutrient profile and heavy metal composition of <italic>Pleurotus ostreatus</italic>. The product was tested in two doses applied at three different timings: T2: 3 g kg⁻¹/spawning, T3: 3 g kg⁻¹/after first harvest, T4: 3 g kg⁻¹/spawning and after first harvest, T5: 5 g kg⁻¹/spawning, T6: 5 g kg⁻¹/after first harvest, and T7: 5 g kg⁻¹/spawning and after first harvest. Compared to control (T1: non-treated substrate), mushrooms’ fibers and carbohydrates increased in all treatments, recording the highest values in T4 (4.16%) and T3 (18.42%), respectively. Protein content was higher in mushrooms of substrates treated at spawning, with a 0.33% improvement in T5. Fat content decreased in T3, T4, T6, and T5. Total sugars decreased in mushrooms of treated substrates, and glucose was the dominant sugar in mushrooms. Fructose increased in mushrooms of T3 and T4. Calcium, iron, and potassium decreased in mushrooms of treated substrates. Sodium decreased in T3, T5, and T7, magnesium increased in T2, and phosphorus increased only in T2 and T7. Copper content of all treated mushrooms was in the standard safe limit (&lt; 40 ppm), and it decreased in T2, T4, and T5 by around 2.5, 6.6, and 5.1 ppm, compared to control. However, zinc content increased in mushrooms of all treated substrates, and nickel and lead, increased by respective ranges of 2.8−11.88 ppm and 9.1−21 ppm, higher than the safe limits. The product presented a risk of heavy metal bioaccumulation even with a low dose.