Biological activities and GABA content of Ma-Lod (Elaeagnus latifolia Linn.)

Abstract

Elaeagnus latifolia Linn. is a type of wild edible fruit plant belonging to the family Elaeagnaceae locally known as Ma-Lod in the Upper North of Thailand. In this study, the fruit of twelve Ma-Lod trees, namely ML-1, ML-2, ML-3, ML-4, ML-5, ML-6, ML-7, ML-12, ML-16, ML-17, ML-18, and ML-19, collected from Sangkhom District, Nong Khai Province were investigated for tyrosinase inhibitory activity, antioxidant activity, free radical scavenging activity, total phenolic content and GABA content. The results show that the reducing power of Ma-Lod flesh extracts highly correlated with their phenolic contents indicating phenolic compounds could be one of the main contributors to oxidant reducing power. Among twelve tested Ma-Lod trees, fruit flesh extracts of ML-1, ML-4, ML-5, and ML-17 were considered to be a promising source of biologically active compounds due to their high total phenolic contents, antioxidant activity and outstanding of tyrosinase inhibitory activity. GABA was also found in Ma-Lod flesh extract and the high recovery of GABA after passing through the Dowex 50W-X8 column was obtained. This wild and underutilized fruit exhibits many valuable characteristics which deserve conservation and utilization. It could be a potential source of natural biologically active compounds in the development of value-added products such as antioxidant-rich products and cosmetics. In addition, new investigation of the presence of GABA in Ma-Lod fruit might lead to the development of GABA food supplement in the future.