Biochemical, compositional, and spectral analyses of İsot (Urfa pepper) seed oil and evaluation of its functional characteristics

Assessing the concentration of conjugated fatty acids within pomegranate seed oil using quantitative nuclear magnetic resonance (qNMR)

INTRODUCTION

Pomegranate seed is rich in oil, and seed oil of pomegranate consists of conjugated fatty acids with different percentages.

OBJECTIVES

The current contribution covers how to determine percentages of different isomeric conjugated fatty acids.

METHODS

The percentages of these isomers are analysed by quantitative nuclear magnetic resonance (qNMR) using benzoic acid as an internal reference chemical with a well-defined amount. Linear mathematical equations are developed for the quantitative analysis of fatty acids found in pomegranate seed oil.

RESULTS

The developed approach is utilised for the pomegranate seed oils prepared in the laboratory and tested for commercial samples. Among the oils derived at the laboratory, the Yeni Hicaz pomegranate cultivar seeds yielded the highest fraction of punicic acid. Among the acids, punicic acid was the one with the highest fraction, while linolenic acid was the one with the lowest percentage.

CONCLUSIONS

These results are important in identifying pomegranate seed oils. Among the commercial samples tested with the current approach, only one of them showed similar content analysis as in the laboratory-derived oils.

Effect of Ultrasound-Assisted Solvent Enzymatic Extraction on Fatty Acid Profiles, Physicochemical Properties, Bioactive Compounds, and Antioxidant Activity of Elaeagnus mollis Oil

Elaeagnus mollis oil extracted from the nuts of Elaeagnus mollis Diels can be used in food and pharmaceutical applications due to its excellent nutritional value. An ultrasound-assisted solvent enzymatic extraction (UASEE) method was used to extract oil from Elaeagnus mollis Diels with n-hexane solvent (1:11.6 g/mL) and 1.1% (w/w) mixed enzymes (neutral protease:hemicellulase:pectinase = 1:1:1, w/w/w). The physicochemical properties, fatty acid profile, bioactive compounds, antioxidant activity, morphology, and thermal stability of UASEE oil were investigated and compared with soxhlet extraction (SE) oil and cold pressing (CP) oil. The UASEE oil exhibited a higher content of unsaturated fatty acids (93.96 ± 0.28%), total tocopherols and tocotrienols (147.32 ± 2.19 mg/100 g), total phytosterols (261.78 ± 5.74 mg/100 g), squalene (96.75 ± 0.31 mg/100 g), total phenolic content (84.76 ± 2.37 mg GAE/kg), and antioxidant activity (12.52 ± 0.28 mg/mL) than SE and CP oil. The lower peroxide value and acid value in UASEE oil indicated its better quality and lower likelihood of rancidity. The oil obtained using UASEE had higher thermal stability as well, as indicated by thermogravimetric analysis. Scanning electron microscopy (SEM) showed that the UASEE process causes damage to cell walls, and the leakage of substances in the cells facilitates extraction in the following step. Thus, UASEE is a promising processing method for the extraction of Elaeagnus mollis oil.

Gum arabic/maltodextrin microencapsulation confers peroxidation stability and antimicrobial ability to pepper seed oil

In this study, pepper seed oil (PSO) was microencapsulated by spray drying at optimum conditions: oil/total solid material at 20% (w/w), gum Arabic/maltodextrin (GA/MD) at 1/5 (w/w), and air inlet temperature of 184 °C. Particle size distribution and morphology of the PSO powder (PSOP) were determined by a laser particle diameter analyzer and scanning electron microscopy (SEM). Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) were employed to identify the specific chemical groups of PSO, MD, and GA in the PSO-GA/MD complexes. The thermal stability of PSOP was evaluated by thermogravimetric (TGA) and differential thermal analysis (DTA). PSOP displayed inhibitory activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Enterococcus faecalis although PSO had an antimicrobial activity against only Staphylococcus aureus. GA/MD microencapsulation resulted in significant preservation of PSO against oxidation during storage period.