Phytochemical Components of Struchium Sparganophora (Ewuro Odo) Leaf
The effect of processing on the antioxidant properties and proximate composition of Struchium sparganophora leafy vegetable was evaluated. The processing included: abrasion with cold water (WH); abrasion and blanching with boiled water (WHH); abrasion with 10g of common salt (WS) and unprocessed vegetable (NP). Standard methods were used to analyze the processed and unprocessed vegetables for antioxidant activities, antioxidant phenolic compounds and the proximate. The results of the study showed that Protein content of unprocessed S. sparganophora was 3.64g/100g and was reduced to 1.94-2.66g/100g by processing. Fat and ash contents were likewise reduced by processing while fibre and moisture contents were not reduced by abrasion with cold water. S. sparganophora had antioxidant activity of 93.9%. Abrasion with cold water did not affect this value significantly (P=0.05). Neither did it affect the concentrations of anthocyanin and proanthocyanidin significantly (P=0.05). However, total phenol and flavonoid concentrations were significantly affected by processing. Struchium sparganophora is best consumed unprocessed, however, abrasion with cold water might be an alternative if the nutrients and the antioxidants in Struchium sparganophora will not be compromised
Struchium sparganophora (Linn.) Ktze. commonly called water bitter leaf and locally called “ewuro odo” in the south western Nigeria belongs to the Asteraceae Family. S. sparganophora is a water plant consumed as a leafy vegetable in Nigeria. Vegetables play significant role in human nutrition, especially as a source of vitamins, minerals and dietary fibre. Vegetables contain compounds that are valuable antioxidants and protectants. The main protective action of vegetables has been attributed to the presence of antioxidants, especially antioxidants vitamins and phenolic compounds such as flavonoids
In Nigeria, green leafy vegetables are usually subjected to various post-harvest treatments such as blanching, soaking, abrasion with or without salt, in order to improve their palatability and to remove the bitter taste and some of the acids present in the vegetables .
The various processing techniques had been reported to alter both the nutrient, antinutrient and antioxidant property of some commonly consumed plant foods in Nigeria . This study therefore evaluated the effects of commonly practiced vegetable processing methods on the chemical compositions of S. sparganophora.