4TH International Congress on Technology - Engineering & SCIENCE - Kuala Lumpur - Malaysia (2017-08-05)

The Phenolic Content And Antioxidant Activity Of White Hypsizygus Tessellatus (bunapi Shimeji) And Flammulina Velutipes (enoki) Mushroom Water Extracts
The cause of a reasonable percentage of human cancer and other life threatening diseases could be traced to the food and the additives we eat daily. Most of the additives classified as antioxidants and other forms of nutrients have one side effect or the other on our body. There is therefore, a need to source for alternative natural compounds with antioxidant properties [1]. Mushrooms have existed for ages as food for man and as a source of traditional medicine. They are endowed with vitamins, low fat, dietary fibers, minerals and small carbohydrate calories [2]–[4]. They have also been reported as a potent source of polyphenols with good antioxidant properties [5]. The anti-cancer and antimicrobial activities of mushrooms have been attributed to the phenolic content by many researchers [2], [6]–[10]. These compounds exhibit biological activities through their strong scavenging activities against the cancer-causing reactive oxygen species (ROS) which are formed during normal cell metabolic activities. The body’s defense system could be boosted by the introduction of extra compounds such as natural vitamins, proteins and minerals with antioxidant properties [11]. In this study, the phenolic content and radical scavenging properties of Bunapi shimeji and Enoki water extracts was evaluated. The antibacterial activities were also evaluated against selected Gram-positive (G+) and Gram-negative (G-) bacteria. These mushrooms were studied because they serve as a source of food to the Malaysian people who have a limited knowledge of the medicinal values of these mushrooms. During the study, the phenolic content of the mushroom extracts was evaluated using Gallic acid as the standard, while DPPH radical scavenging was used to assess the antioxidant activities. The inhibition of bacterial growth in broth cultures was the yardstick for determining the antibacterial activity of the extracts, gentamycin was used as the standard antibiotic agent. From the results, the water extracts from the cap and stalk of Enoki mushroom showed the highest phenolic contents (197.2 ± 4.8 and 105.6 ± 4.8 µgGAE/mg, respectively) and scavenging activities (> 70 % and > 60 %, respectively) while the extracts from the cap and stalk of Bunapi shimeji showed phenolic contents of (phenolic: 125.0 ± 0.0 and 119.4 ± 4.8 µgGAE/mg, respectively); with a radical scavenging activity of < 60 %). For the antibacterial activities, the water extracts of Bunapi shimeji showed the strongest activity against E. coli and S. marscenscens, with some levels of inhibition against S. aureus and B. subtilis likely due to cell wall variation. The water extracts from Enoki mushroom showed antimicrobial activity against E. coli and S. marscenscens as well. The study showed that the studied mushrooms are a good source of natural antioxidants and antibacterial.
Keywords: Hypsizygus tessellatus (Bunapi shimeji), Flammulina velutipes, phenolic content, antioxidants
Chinonso I Ukaegbu, Samiur R Shah, Hazrulrizawati Abd Hamid, Jalal KCA