Determination of Oxalates in Corms of Selected Taro (Colocasia esculenta) Varieties in Malaysia Using Ultra High-Performance Liquid Chromatography

Abstract

Aims: To determine the oxalate contents in different varieties of taro (Colocasia esculenta) collected in Peninsular Malaysia. Study Design: Ultra High-Performance Liquid Chromatography (UHPLC) with UV detector (Diode Array Detection, (DAD)) was used to determine the total and soluble oxalate contents in different varieties of taro corms. Meanwhile, the insoluble oxalate content (calcium oxalate) was estimated from the subtraction of soluble oxalate content from total oxalate content. Place and Duration of Study: Malaysian Agriculture Research and Development Institute (MARDI Headquarters), Persiaran MARDI-UPM, 43400 Serdang, Selangor, Malaysia between December 2018 to December 2019. Methodology: 9 different varieties of taro were collected from different locations in Peninsular Malaysia. All the samples were analysed for their oxalate contents. Extractions were carried out to determine the total oxalate and soluble oxalate contents. All the samples were analysed using UHPLC. The generated data of oxalate contents were analysed using Analysis of Variance (ANOVA). Results: There is a significant difference (P <.05) between the oxalate content in the examined varieties with respect to the amount of total, soluble and insoluble oxalate contents. The putih variety has significantly the highest amount of total oxalate content with 218.8 ± 28.2 mg/100 g DW (dry weight) followed by the udang variety with 184.2 ± 24.7 mg/100 g DW and the wangi variety with 178.3 ± 5.1 mg/100 g DW. Tapak badak variety has the lowest total oxalate content with 70.5 ± 20.1 mg/100 g DW. Result showed that wangi variety has significantly the highest soluble oxalate content with 135.1 ± 4.8 mg/100 g DW followed by udang with 100.9 ± 49.8 mg/100 g DW. The lowest soluble oxalate content was found in tapak badak with 17.7 ± 2.9 mg/100 g DW. Conclusion: Despite many factors contributing to the difference in oxalate content between varieties, this study would help researchers or policy makers to suggest potential taros for commercial cultivation.