ABSTRACT
ABSTRACT Recent findings in amino acid metabolism and the differences between normal, healthy cells and neoplastic cells have revealed that targeting single amino acid metabolic enzymes in cancer therapy is a promising strategy for the development of novel therapeutic agents. Arginine is derived from dietary protein intake, body protein breakdown, or endogenous de novo arginine production and several studies have revealed disturbances in its synthesis and metabolism which could enhance or inhibit tumor cell growth. Consequently, there has been an increased interest in the arginine-depleting enzymes and dietary deprivation of arginine and its precursors as a potential antineoplastic therapy. This review outlines the most recent advances in targeting arginine metabolic pathways in cancer therapy and the different chemo- and radio-therapeutic approaches to be co-applied.
Subject(s)
Arginine/analysis , Neoplasms/drug therapy , Diet/adverse effects , Enzymes/analysisABSTRACT
Calcium alginate beads containing pomegranate peels' polyphenol extract were encapsulated by ionic gelation method. The effects of various formulation factors (sodium alginate concentration, calcium chloride concentration, calcium chloride exposure time, gelling bath time maintaining, and extract concentration) on the efficiency of extract loading were investigated. The formulation containing an extract of 1 g pomegranate peels in 100 mL distilled water encapsulated with 3 % of sodium alginate cured in 0.05 M calcium chloride for 20 minutes and kept in a gelling bath for 15 minutes was chosen as the best formula regarding the loading efficiency. These optimized conditions allowed the encapsulation of 43.90% of total extracted polyphenols and 46.34 % of total extracted proanthocyanidins. Microencapsulation of pomegranate peels' extract in calcium alginate beads is a promising technique for pharmaceutical and food supplementation with natural antioxidants.
Pérolas de alginato de cálcio, contendo polifenóis de extrato de casca de romã, foram encapsuladas pelo método de gelificação iônica. Os efeitos de vários fatores de formulação (concentração de alginato de sódio, concentração de cloreto de cálcio, cloreto de cálcio, o tempo de exposição, o tempo de manutenção do banho de gelificação e a concentração do extrato) sobre a eficiência de carga do extrato foram investigados. A formulação que contém 1 g extrato de casca de romã em 100 mL de água destilada, encapsulado com 3% de alginato de sódio curada em 0,05 M de cloreto de cálcio durante 20 minutos e mantido em banho de gelificação por 15 min foi escolhida como a melhor em relação à eficiência de carga. Estas condições otimizadas permitem o encapsulamento de 43,90% do total de polifenóis extraídos e de 46,34% do total de proantocianidinas extraídas. A microencapsulação de extrato de cascas de romã em esferas de alginato de cálcio é uma técnica promissora para a suplementação farmacêutica e de alimentos com antioxidantes naturais.