No abstract

Essential oils (EOs) are known for uses in various fields such as perfume, cosmetic, pharmaceutical and food industries. Agricultural wastes are among the resources of EOs that produced and disposed of in large quantities annually. Hence, in this study, for the first time, EOs available from pistachio fruit [fruit pistachio shells (FPS) and fruit pistachio cluster (FPC)] were used to the extraction of EOs. The Clevenger device and distilled water were used to extract EOs. The amount of total phenolic compounds (TPC) by Folin-ciocalteu reagent and the radical scavenging ability (RSA%) of FPS and FPC extracted by the soaking method were also measured. The RSA% of EOs and extracts in the presence of DPPH free radicals was evaluated by the IC50 index. Chemical composition of EOs detected by mass spectrometric gas chromatography. Notwithstanding amounts of extraction efficiency by water in the soaking method from FPS and FPC was 4.6% and 3.2% respectively, EOs extraction efficiency from FPC and FPS was 2.10% and 0.13% respectively. TPC in FPS and FPC was 958.38 and 796.25 mgGA/100g dry material respectively. The amount of IC50 of FPS was 3760.69 ppm and near to RSA% of BHT (2354.36 ppm). Statistical difference was observed between the RSA of EOs and positive control antioxidant (P < 0.05). The RSA of antioxidant extracts and TPC showed positively correlated. The major compounds identified in FPS were the D-limonene, α-thujene and terpinolene, abundance respectively, and the major components of FPC were α-thujene and α-pinene, abundance respectively.

No abstract

Because of health concerns regarding synthetic antioxidants, natural antioxidant compounds are being considered by scientists. Bioactive peptides have been shown to have various physiological functions, such as antioxidative activity. Pomegranate seed protein, the by-product of the pomegranate seed oil industry, can be a good source of bioactive peptides. The optimum conditions for enzymatic hydrolysis of pomegranate seed protein with alcalase were determined using a response surface methodology. The influence of different temperatures (45-55 °C), times (30-180 min), and enzyme to substrate (E/S) ratio (1-3% w/w) on DPPH scavenging power and ferric reducing activity as the responses, were studied. Also, the degree of hydrolysis and the surface hydrophobicity of samples were determined. Moreover, using scanning electron microscopy and electrophoresis technique, microscopic structure and molecular weight of hydrolysate, were studied respectively. Alcalase-derived hydrolysates showed a DPPH scavenging activity (88 ± 0.97 %) and ferric reducing power (0.5 ± 0.83) at optimum conditions of hydrolysis (48.8°C, 97.5 min, E/S ratio 1.3%w/w). The degree of hydrolysis coincided with 36 ±1.2%. An increase in the surface hydrophobicity of the protein during hydrolysis confirmed the unfolding of the pomegranate seed protein structure. The presence of low-molecular-weight peptides was evidenced by the electrophoresis technique. As well as the SEM showed that protein fragments had been reduced to small sizes following enzymatic treatments. According to the results of this study, pomegranate seed protein hydrolysate can be considered a suitable source of antioxidants with an aggregate market value in food formulations