Comparative Study of Soybean Oil and the Mixed Fatty Acids as Acyl Donors for Enzymatic Preparation of Feruloylated Acylglycerols in Ionic Liquids

Effect of Ferulic Acid and Its Derivatives on Cold-Pressed Flaxseed Oil Oxidative Stability and Bioactive Compounds Retention during Oxidation

Ferulic acid (FA) is a naturally occurring phenolic antioxidant that is widely used in the food, pharmaceutical, and cosmetic industries due to its low toxicity. Its derivatives also find numerous industrial applications and may have even higher biological activity than ferulic acid. In this study, the effect of the addition of FA and its derivatives-including vanillic acid (VA), dihydroferulic acid (DHFA), and 4-vinylguaiacol (4-VG)-on the oxidative stability of cold-pressed flaxseed oil and the degradation of bioactive compounds during oxidation was investigated. The results showed that FA and its derivatives affected the oxidative stability of flaxseed oil, but their antioxidant activity depended on the concentration (25-200 mg/100 g oil) and temperature of treatment (60-110 °C). Based on Rancimat test results, flaxseed oil oxidative stability predicted at 20 °C increased linearly with ferulic acid concentration, while its derivatives effectively prolonged the induction time at lower concentrations (50-100 mg/100 g oil). The addition of phenolic antioxidants (80 mg/100 g) generally showed a protective effect against polyunsaturated fatty acids (DHFA and 4-VG), sterols (4-VG), tocols (DHFA), squalene, and carotenoids (FA). The exception was VA, which increased the degradation of most bioactive compounds. It is believed that adding properly composed mixtures of FA and its derivatives (DHFA and 4-VG) can extend the shelf life of flaxseed oil and provide nutritional benefits.

Applying and Optimizing Water-Soluble, Slow-Release Nitrogen Fertilizers for Water-Saving Agriculture

A novel, eco-friendly, water-soluble, slow-release nitrogen fertilizer was developed to enhance water solubility and nitrogen use efficiency. A test was performed to determine the interactive effects of process parameters using a central composite design and response surface methodology. The quadratic polynomial mode for slow-release nitrogen was determined and yielded differences (p < 0.01). The soluble, slow-release nitrogen fertilizers were analyzed using nuclear magnetic resonance, and the release characteristics of soil nitrogen from the fertilizer at 25 °C were also determined. The effects of the fertilizer on plant growth were determined using rape (Brassica campestris L.) outdoors. Conversion rates from the fertilizer to inorganic nitrogen were 30.0, 52.2, and 60.0% at 7, 24, and 40 days, respectively. This soluble, slow-release nitrogen fertilizer resulted in increased yields and nitrogen use efficiencies in rape plants compared with a standard urea fertilizer. The yields of rape plants treated with a mixture of the fertilizer and urea (BBW100%) were significantly higher than all of the other treatments. When the nitrogen application rate was reduced by 20%, the resulting "SSNF80%" and "BBW80%" treatments produced nearly the same yields as "UREA100%". Nitrogen use efficiencies for treatments with the study fertilizer ("SSNF") and the mixture bulk blend fertilizer ("BBW") were significantly higher than that with urea ("UREA") treatment by 37-52 and 42-43%, respectively. Hence, the fertilizer showed great potential for improving the production of rape and possibly other crops.