Effect of Roasting on the Phytochemical Properties of Three Varieties of Marble Vine (Dioclea reflexa) Using Response Surface Methodology

Abstract

This study assessed the optimum roasting conditions on the phytochemical properties of three varieties of Dioclea reflexa seeds using response surface methodology. Roasting conditions were varied using temperature (110°C~200°C) and time (10~40 min). Phytochemical components (phenolics, tannin, flavonoids, cardiac glycoside, and steroids) of the seeds were screened and estimated. The study showed that availability of phytochemical activities was heat-dependent. An increase in roasting temperature beyond 110°C for 10 min resulted in a decrease in total phenolic (TP) and flavonoid (TF) contents. However, prolonged durations of roasting favored increased amounts of TP and TF in dark and light varieties. Total sterol, tannin, and cardiac glycoside contents increased with increasing roasting temperature and time. The desirability of the models were 0.76, 0.74, and 0.72 for black, dark brown, and light brown, respectively. The coefficients of regression (R2), ranged from 0.66 to 0.98 signifying accuracy of the model. The following models (cubic, quadratic, and 2 factor interaction) were significant (P≤0.05). We found that roasting time influenced the phytochemical properties of D. reflexa to a greater extent than temperature. The optimum roasting temperature and time was found to beat 110°C, 35 min, 40 min, and 32 min in black, dark brown, and light brown varieties, respectively. Roasting conditions significantly affects the phytochemical contents of three varieties of D. reflexa seed flour (P<0.05). Therefore, D. reflexa holds the potential to be used in development of functional foods and in therapeutic applications to promote health.

Cognitive impairment by non‐insulin‐dependent diabetes mellitus was attenuated by dietary supplements of marble vine (Dioclea reflexa) and plantain (Musa paradisiaca) dough meals in albino rats

“…The processing of marble vine was carried out as previously described by Ajatta et al. (2019). Wholesome seeds were first sorted, washed, and dried at ambient temperature for 2 days.…”

“…It is rich in bioactive substances such as L‐3, 4‐ dihydroxyphenylalanine (L‐DOPA) (Adebowale, Adeyemi, & Oshodi, 2005), The phytochemical properties and antioxidant activities of three varieties was earlier reported by Ajatta et al. (2019). Futhermore, Plantain ( Musa paradisiaca ) is a plant with green leaves and herbaceous stem belonging to the family Musaceae .…”

“…(American Diabetes Association, 2015). The rate at which DM increases in both developed and developing countries is becoming alarming, despite several efforts made in preventing the occurrence of this degenerative diseases (Ajatta et al., 2019; Zimmet, Cowie, Ekoe, & Shaw, 2004). It was estimated by International Diabetes Federation (IDF, 2017), that about 425 million people are suffering from diabetes worldwide and it is expected that by year 2030, the number would have increased to 522 million.…”

“…Marble vine or sea pulse ( D. reflexa) is an underutilized leguminous seed, belonging to the family Leguminosae and sub‐family Papillionoideae (Ajatta et al., 2019; Akinyede, Girgih, Osundahunsi, Fagbemi, & Aluko, 2017). It is majorly found in the South‐western part of Nigeria.…”

“…Few authors have reported its applications as a rheology modifier and medicinal applications (Atawodi & Iliemene, 2014). Nutrient composition and its usage in treating several infections and pains such as rheumatism, itching, diabetes, and inflammations (Ajatta et al, 2019;Akinyede, Amoo, & Eleyinmi, 2005;Faleye, 2012). It is rich in bioactive substances such as L-3, 4-dihydroxyphenylalanine (L-DOPA) (Adebowale, Adeyemi, & Oshodi, 2005), The phytochemical properties and antioxidant activities of three varieties was earlier reported by Ajatta et al (2019).…”