Impact of different processing methods on phytochemicals and anti-oxidative properties of five varieties of Mushrooms

Abstract

Mushrooms are rich in vitamin D, antioxidants, and phenolic compounds. Different processing techniques may be used to increase shelf life and reduce spoilage of mushrooms. The objective of this study was to determine total phytochemical and total antioxidant activity of extracts of five varieties (Portabella, White Button, White Beech, Oyster & Seafood) of mushrooms (fresh, oven dried & sautéed). The antioxidant activity was measured by 2,2-diphenyl-1-picrylhydrazyl radical solution (DPPH), ferric reducing antioxidant power (FRAP), Trolox equivalence antioxidant capacity assay (TEAC), and nitric oxide radical scavenging activity (NORS). All samples were freeze-dried followed by preparation of methanol extracts. Oven dried and cooked Portabella, and Oyster Mushrooms had lower total phenolic (295.05 and 135.54 μg GAE/100g DW) compared to sautéed (417.49 μg GAE/100g DW) and raw (446.95 and 309.28 μg GAE/100g DW). Sautéed Portabella (111.97 μg C.E/100g DW) and Oyster samples had higher total flavonoid content compared to fresh (81.45 and 64.70 μg C.E/100g DW) and oven dried (72.38 and 66.45 μg C.E/100g DW) samples. Highest FRAP activity was observed in raw Portabella (3.94 mM Fe(II)/100g DW) and Oyster extracts (2.62 mM Fe(II)/100g DW) compared to sautéed samples (3.03mM Fe(II)/100g DW) with 1.3 times lower activity. Followed by 1.9 folds reduced FRAP activity in oven-dried Portabella (2.07mM Fe(II)/100g DW), and 1.69 folds' lower action in oven-dried Oyster (1.55mM Fe(II)/100g DW). All the Portabella treatments had 1-2.5 folds higher total phenolic, flavonoid content and FRAP activity compared to Oyster mushrooms. Future research will include using the extracts for the prevention of chronic disease studies. Data from this study will be helpful to determine the processing conditions which will maximize phytochemicals and antioxidants with implications in the development of functional food products.

Comparative antioxidant activity and phytochemical content of five extracts of Pleurotus ostreatus (oyster mushroom)

“…Standard protocols were used to evaluate the various phytochemicals present in the P. ostreatus extracts. The secondary metabolites, alkaloids, anthraquinones and betacyanins, anthrocyanins and betacyanins, coumarins, flavonoids, glycosides, tannins, steroids, saponins, terpenoids, phenols, quinones, cardiac glycosides, acids, phlobatannins, and carbohydrates, were assayed using the procedures described by Rahimah et al 22 , Jiang et al 23 , Bristy et al 24 , Hossen et al 25 , Kaur et al 26 and Mishra et al 21 .…”