Phytochemical Composition, Antioxidant and Xanthine Oxidase Inhibitory Activities of Amaranthus cruentus L. and Amaranthus hybridus L. Extracts

Abstract

This paper describes a preliminary assessment of the nutraceutical value of Amaranthus cruentus (A. cruentus) and Amaranthus hybridus (A. hybridus), two food plant species found in Burkina Faso. Hydroacetonic (HAE), methanolic (ME), and aqueous extracts (AE) from the aerial parts were screened for in vitro antioxidant and xanthine oxidase inhibitory activities. Phytochemical analyses revealed the presence of polyphenols, tannins, flavonoids, steroids, terpenoids, saponins and betalains. Hydroacetonic extracts have shown the most diversity for secondary metabolites. The TLC analyses of flavonoids from HAE extracts showed the presence of rutin and other unidentified compounds. The phenolic compound contents of the HAE, ME and AE extracts were determined using the Folin–Ciocalteu method and ranged from 7.55 to 10.18 mg Gallic acid equivalent GAE/100 mg. Tannins, flavonoids, and flavonols ranged from 2.83 to 10.17 mg tannic acid equivalent (TAE)/100 mg, 0.37 to 7.06 mg quercetin equivalent (QE) /100 mg, and 0.09 to 1.31 mg QE/100 mg, respectively. The betacyanin contents were 40.42 and 6.35 mg Amaranthin Equivalent/100 g aerial parts (dry weight) in A. cruentus and A. hybridus, respectively. Free-radical scavenging activity expressed as IC50 (DPPH method) and iron reducing power (FRAP method) ranged from 56 to 423 µg/mL and from 2.26 to 2.56 mmol AAE/g, respectively. Xanthine oxidase inhibitory activities of extracts of A. cruentus and A. hybridus were 3.18% and 38.22%, respectively. The A. hybridus extract showed the best antioxidant and xanthine oxidase inhibition activities. The results indicated that the phytochemical contents of the two species justify their traditional uses as nutraceutical food plants.

Phenolic content and antioxidant capacity of extracts ofLaurus nobilisL.,Coriandrum sativumL. andAmaranthus hybridusL.

“…These results are in agreement with the data previously reported by Sultana, Anwar, and Ashraf (2009), who studied the effect of different extracting solvents (absolute ethanol, absolute methanol, aqueous ethanol and aqueous methanol) on the extraction of phenolic compounds from medicinal plants and obtained higher yields with alcohol-water mixtures. As reported by Nana et al (2012), the phytochemical composition of A. hybridus indicated the presence of polyphenols and yields of 9.75, 8.30 and 7.75 GAE/100 mg were obtained in hydroacetonic, methanolic and aqueous extracts. Martins et al (2010) mentioned that addition of large amounts of water as part of the solvent resulted in enhancement of extraction efficiency, possibly due to increased swelling of plant material in the presence of water and by increasing contact surface between plant matrix and solvent.…”

“…Rahiman, Tantry, and Kumar (2013) reported a high phenolic content in Coriandrum sativum extracts. On the other hand, the antioxidant capacity and phenolic content of Amaranthus hybridus have also been confirmed in previous studies (Chipurura, Muchuweti, Parawira, & Kasiyamhuru, 2011;Nana, Hilou, Millogo, & Nacoulma, 2012). The present study was aimed to define the optimum conditions of ethanol concentration and time for heat-*Corresponding author.…”

“…Similarly, Wangensteen, Samuelsen, and Malterud (2004) observed that the antiradical activity of extracts of coriander for the DPPH radical inhibition was only 15%. Rahiman et al (2013) studied the phenolic content in ethanolic extracts of C. sativum (70.24 mg/g) but did not find any correlation between the antioxidant activity and the phenolic content, which is in contrast with the report by Sulaiman, Sajak, Ooi, Supriatno, and Seow (2011) who correlated the phenolic content with the antioxidant activity present in ethanolic extracts of C. sativum (r = 0.9998, p < 0.001); this variation probably could be influenced by environmental factors (Nana et al, 2012;Upadrasta, Mukhopadhyay, & Banerjee, 2011). On the other hand, Chipurura et al (2011) reported the activity of the antioxidant of A. hybridus and correlated this activity with the phenolic content present.…”

“…HPLC analysis revealed the presence of four phenolic compounds in the L. nobilis extract: coumaric acid, gallic acid, pyrogallol and resorcinol (Table 2), which could be responsible (Nana et al, 2012;Upadrasta et al, 2011). In the case of C. sativum and A. hybridus extracts, no phenolic compounds were detected under the conditions tested, which could be related to the low concentration as evident from low antioxidant activity recorded for these extracts.…”

Degradación Ruminal de Dietas a Base de Biomasa Pos-cosecha de Amaranthus cruentus: Efecto sobre los Protozoos del Rumen y Producción de Gas in vitro

“…Esto se observa claramente en este estudio, donde al incorporar A. cruentus en la ración aumenta la degradación efectiva de la fibra y proteína (Cuadro 2); resultados que coinciden con los reportados por Torres et al La mayor digestibilidad in vitro de los nutrientes en T1 y T4 fue debido al menor contenido de FDN y mayor PC que aporta A. cruentus a la ración (Cuadro 1), ya que la degradación de las proteínas da como resultado péptidos, NH 3 , aminoácidos y ácidos grasos de cadena corta ramificados; compuestos que pueden mejorar las funciones del rumen. Esto estimula el crecimiento microbiano del rumen en general y, específicamente, de las bacterias celulolíticas y proteolíticas, trayendo como consecuencia una mayor digestión de los nutrientes (Hoover y Stokes, 1991); aspecto parcialmente obser- La disminución in vitro de las poblaciones de protozoarios Holotricos y Entodiniomorfos observado en los tratamientos con A. cruentus (Cuadro 4), fue debido posiblemente a la acción directa de los compuestos secundarios (taninos y saponinas) presentes en la biomasa pos-cosecha de A. cruentus (Nana et al, 2012). Estos compuestos tienen un efecto defaunante en el rumen; por ejemplo, el efecto selectivo de las saponinas hacia el colesterol de la membrana celular de los protozoarios que causa su lisis (Jayanegara et al, 2012).…”