Effects of ph and temperature on water under pressurized conditions in the extraction of nutraceuticals from chaga (Inonotus obliquus) mushroom

What if the key to unlocking a mushroom's hidden nutrients was simply adjusting the pH of water under pressure? A new study reveals that Chaga mushroom extracts reach their peak antioxidant power at a surprisingly alkaline pH.

Chaga mushroom, a staple in traditional medicine, is packed with bioactive compounds. But extracting these nutraceuticals efficiently and safely has been a challenge. Researchers have now turned to a modified Swiss water process, using pressurized water at different pH levels and temperatures as a green, food-grade solvent. They tested alkaline and acidic conditions to see which best pulls out the mushroom's beneficial nutrients.

The results are striking. At pH 11.5 and 100°C, the extracts showed the highest total phenolic content and antioxidant activity. Over 20 phenolic compounds were quantified, including notable amounts of protocatechuic acid 4-glucoside, syringic acid, and myricetin. Interestingly, vitamins were reported in Chaga for the first time. Acidic conditions (pH 2.5) excelled at extracting B vitamins and fat-soluble vitamins, with vitamin E levels ranging from 50 to 175 µg per 100 g of Chaga.

Antioxidant minerals also varied with conditions, from 85.94 µg/g at pH 7 to 113.86 µg/g at pH 2.5 (both at 100°C). The study found a strong correlation between total phenolic content and antioxidant activity, suggesting phenolics are key contributors. This novel use of the Swiss water process offers a promising, eco-friendly method for extracting nutrients from Chaga and potentially other matrices, with applications in food and nutraceutical industries.

Key Points

• pH 11.5 at 100°C yielded highest phenolics and antioxidants.
• Vitamins reported first time in Chaga; acidic pH boosts B vitamins.
• Swiss water process as novel green extraction for nutraceuticals.