Antioxidant potential of methanolic extracts and powders of some Cameroonian spices during accelerated storage of soybean oil

Abstract

The efficacy of methanolic extracts and powders of 12 spices (Pimpinella anisum, Scorodophleuszenkeii, Xylopiaparviflora, Eugenia caryophyllus, Fagara leprieurii, Fagara macrophylla, Monodora myristica, Olax subscorpioidea, Xylopiaaethiopica, Allium sativum, Zinziber officinale and Cinnamomum zeylanicum) in stabilizing crude soyabean oil during accelerated storage was assessed. The phytochemical screening revealed the presence of phenols in all the spices except that of Allium sativum. Total phenolic content (TPC) and DPPH radical scavenging activity of the extracts varied significantly (p < 0.01) ranging from 1.34 to 17.72 g GAE/100 g and 18.91% to 96.39% respectively. Extract of Zinziber officinale, Olax subscorpioidea, Fagaramacrophylla, Eugenia caryophyllus and Xylopia parviflora, which offered the highest TPC, exhibited superior antioxidant activity with regard to the DPPH. Furthermore, the antioxidant effectiveness of the extracts and powders was assessed using crude soyabean oil (CSO) as the oxidation substrate. CSO samples stabilized with extracts at a concentration of 500 ppm (w/w) and powders at a concentration of 1000 ppm were subjected to accelerated storage (65˚C, oven heating, 24 days, 8 h heating cycle per day), and analyzed periodically for the extent of oxidative alterations following the measurement of iodine and peroxide value. CSO + BHT at 200 ppm served as standards besides the control. Results reveal Zinziberofficinale, Cinnamomum zeylanicum, Scorodophleuszenkerii, Monodora myristica, Xylopiaaethiopica, Allium sativum, Fagara leprieurii extracts and powders and the powder of Pimpinella anisum to be potent antioxidants for stabilization of crude soyabean oil.

Valorization of soursop flowers (Annona muricata L.) as potent source of natural antioxidants for stabilization of palm olein during accelerated storage

“…Antioxidants compounds present in this extract could be responsible of the observed activity. Similar results have been reported by Mei et al (2014) in sunflower oil and Womeni et al (2013) in soybean oil with extract of Rambutan (Nephelium lappaceum L) and some Cameroonian spices, respectively, during accelerated storage of 24 days at 65°C.…”

“…() in sunflower oil and Womeni et al. () in soybean oil with extract of Rambutan ( Nephelium lappaceum L) and some Cameroonian spices, respectively, during accelerated storage of 24 days at 65°C.…”

“…; Womeni et al. ). But, recently, only few natural sources have been authorized for industrial purpose (case of rosemary) (Cuvelier and Maillard ).…”

“…The majority of natural antioxidants are phenolic compounds or polyphenols and their antioxidant activity is based on their structure, hydrogen-donating potential, ability to chelate metal ions and their synergic actions ORIGINAL RESEARCH Valorization of soursop flowers (Annona muricata L.) as potent source of natural antioxidants for stabilization of palm olein during accelerated storage (Bouba et al 2010). In many studies, natural plants extracts have been used for stabilization of edible oils (Iqbal et al 2008;Womeni et al 2013). But, recently, only few natural sources have been authorized for industrial purpose (case of rosemary) (Cuvelier and Maillard 2012).…”

Chemical Composition and Antioxidant Activity of Syzygium aromaticum and Monodora myristica Essential Oils from Cameroon

“…Various natural sources of antioxidants have already been explored in the past for their antioxidant activity. Amongst these are spices (Nassar et al, 2007;Bouba et al, 2010;Womeni et al, 2013). Spices have been used for thousands of Centuries to enhance the flavour and aroma of food and prolong their shelf-life (Srinivasans, 2005).…”