Selenium Biofortified Ricegrass (Oryza sativa L.) Juice Powder with an Enhancement of Its Selenium Content, Bioactive Compounds Content and Biological Properties

Abstract

In the present day, sprouts have been paid interested to consume in the form of fresh vegetables or as juice since sprouting stage is claimed to be the stage that plants contained the highest bioactive compounds. Wheatgrass juice is the most consuming sprout juice which providing lots of pharmaceutical benefits. However, it can mostly grow in temperate areas. Rice is the plant in similar family to wheat (Poaceae). Among Asian countries, rice is being the most consumable carbohydrates source and the major agricultural crops. However, the consumption of ricegrass juice alike wheatgrass juice are not widespread. None of commercial products are available in the market and less information on its beneficial effects are reported. Therefore, the study was designed to compare the bioactive compounds content and the antioxidant activities of ricegrass juice compared with wheatgrass juice. Results indicated that ricegrass juice contained lower level of chlorophyll and ascorbic acid while contained higher level of phenolics detected by HPLC compared with wheatgrass juice and the comparable level of antioxidant activities. When dedicate the cost of ingredients and the probable benefits achievement, ricegrass juice could be a potential candidate to produce as new functional food. To produce the functional plant foods, bioactive compounds content and biological properties of plants are mostly concerned. Recently, new technologies to improve biological properties has been stated. According to the review of the literature, the bio-fortification is a well-accepted method to improve organic mineral content, trigger the production of bioactive content and enhance the bioactivity using low production cost and can be easily applied. Selenium (Se) is an important trace element in the human antioxidant system. It is well known for antioxidant boosting and effective cancer treatment. The bio- fortification of Se into plants indicated the improvement in phenolics, ascorbic acid, and glucosinolate content as well as antioxidant and anti-cancer properties. Therefore, the experiment was further conducted on the effect of Se bio-fortification at 0, 10, 20, 30 and 40 mg/L into ricegrass and investigated the bioactive compounds content and biological properties. Results showed that the fortification of Se into ricegrass had a limitation at 40 mg/L. The addition of 40 mg/L Se can increase the highest content of Se compounds, especially in the organic form. The addition of 10 ppm Se could increase the highest level of total phenolic content (TPC) and antioxidant activities but not to the large extent. Consequently, the treatment of control (RGO), the treatment which contained the highest in TPC (RG10) and the highest in Se content (RG40) were chosen to the study on biological properties in cell lines and microorganisms model. Ricegrass juice extract was firstly identified on its predominantly polyphenols using mass spectroscopy (LCMS) and found that flavone glycosides were the foremost group. Results on biological properties revealed that ricegrass juice provided the effect of enhancing probiotic bacteria number namely, Lactobacillus plantarum, on its late-log phase and can prolong their life-cycle. It could also inhibit HT-29 colon cancer cells, and propose role in reducing lipid peroxidation and nitric oxide production in RAW264.7 murine macrophage cells. Moreover, while examined the effect of ricegrass juice against cadmium toxicity in HEK293 kidney cells, the extract could reduce the number of cell death while pre-incubation and co-incubation with cadmium by reducing the lipid peroxidation rate as well as reduce the damaging to DNA determined by comet assay. The extract RG40 exhibited the greatest ability on all activities because it contained an extra amount of Se which is the cofactor of GPX, the antioxidant enzymes in the human body in combination with polyphenols compounds in ricegrass. Therefore, it strengthened the antioxidant protection to cells. The outcomes of this study indicated that ricegrass juice bio-fortified with Se at 40 mg/L produced from Chainatl had potential to produce as new functional food which provides tons of benefits and offered the added value to rice in the future.