Frying stability of sunflower oil blended with jujube (Ziziphus mauritiana Lam.) leaf extract

Chemical composition and mosquitocidal activity of methanolic leaf extracts from Ziziphus mauritiana L. against Aedes aegypti L. and Culex quinquefasciatus Say

BACKGROUND OBJECTIVES

Mosquito vectors are a significant cause of pathogen transmission to both animals and humans. Mosquitoes are responsible for transmitting various diseases, including chikungunya, filariasis, West Nile fever, dengue, malaria, and Zika fever, placing approximately 80% of the world's population at risk of infection at any given time. Controlling mosquitoes has become a multifaceted challenge, influenced by diverse environmental factors such as deforestation, urbanization, and climate change on a global scale. For centuries, medicinal plants have been utilized as bioinsecticides to control insect pests. Ziziphus mauritiana, also known as Chinese apple or Indian jujube is a deciduous thorny tree or shrub. Different parts of the Z. mauritiana plant have been traditionally used to treat various common diseases, a practice still prevalent in India and China.

METHODS

In the current investigation, the chemical properties of Z. mauritiana leaf extract were examined through UV-Vis Spectroscopy, Fourier Transform Infra-Red Spectroscopy (FTIR), and GC-MS Analysis. Second and fourth instar larvae, as well as pupae, of Aedes aegypti and Culex quinquefasciatus were subjected to different concentrations of the methanolic extract of Z. mauritiana for 24 h and 48 h to assess larvicidal and pupicidal activity.

RESULTS

The FT-IR spectrum analysis revealed the presence of various functional groups in the chemical compounds extracted from Z. mauritiana , including amines, aromatics, alkanes, alkyls, carbonyls, and carboxylic acids. Additionally, GC-MS analysis identified Isoborneol (25.37%), 4-Acetylbutyric Acid (26.82%), and 2-Vinyl- 9-[Beta-D-Ribofuranosyl] Hypoxanthine (24.24%) as the three major phytoconstitutents in the methanol extracts of Z. mauritiana. Regarding the larvicidal activity, the methanolic extract of Z. mauritiana exhibited LC 50 values of 155.67 mg/L and 208.57 mg/L for second instar larvae, and 177.68 mg/L and 252.13 mg/L for fourth instar larvae of Cx. quinquefasciatus and Ae. aegypti, respectively, after 24 h of exposure. For pupicidal activity, the LC 50 values were 502.02 mg/L and 514.99 mg/L on pupae of Cx. quinquefasciatus and Ae. aegypti, respectively, within 24 h.

INTERPRETATION CONCLUSION

Overall, the GC-MS analysis provides valuable insights into the chemical composition of the Z. mauritiana extract, highlighting its potential as a natural and eco-friendly alternative for combating insect vectors and contributing to integrated mosquito management programs.

Effect of phenolic extracts from Camellia oleifera seed cake on the formation of polar compounds, core aldehydes, and monoepoxy oleic acids during deep-fat frying

The frying process is an excellent way to obtain food with desirable sensory. However, some harmful substances, such as aldehydes and monoepoxy oleic acids, could also be produced. This study mainly explores the inhibition of polyphenols from the Camellia oleifera seed cake extract (CSCE) on the formation of polar compounds, core aldehydes, and monoepoxy oleic acids during deep-fat frying. The results showed that the CSCE could significantly decrease peroxide, p-anisidine, total polar, and monoepoxy oleic acids compared with other groups. In addition, the CSCE could significantly inhibit the generation of oxidized triacylglycerol polymer (TGP) and oxidized triacylglycerol (ox-TG), indicating its anti-polymerization activity. The total amount of core aldehydes and glycerol ester core aldehydes (9-oxo) in soybean oil was significantly reduced. Furthermore, CSCE had a better inhibitory effect on monoepoxy fatty acids than TBHQ. Our results might be helpful to provide a basis for the search for new natural antioxidants.

Impact of Purslane (Portulaca oleracea L.) Leaves Extract to Enhance the Anti-oxidant Potential of Edible Oils during Heating

The present work deals/ reveals with the effect of purslane leaves extract on the stability of soybean oil during heating and the acceptability of oil after preparation of poori (an Indian fried bread) by frying and its sensory evaluation. The ethanolic purslane leaves extract was blended with soybean oil at three different concentrations such as, 500, 1000 and 1500 ppm (T1, T2 and T3) and compared with control. The sample added with 100 ppm TBHQ was used as a positive control. Assessment of antioxidant activity of the ethanolic extract of purslane leaves was carried out by the estimation of total phenolic content, loss of β-carotene and antioxidant activity. The heating (173±2°C for 24 h; 8 h heating cycles per day) performance of soybean oil incorporated with purslane leaves extract was evaluated in terms of peroxide value, free fatty acid, total polar material and fatty acid composition. The thermal stability of the oils was evaluated using differential scanning calorimeter. The poori was prepared to check the acceptability of the oil. Results suggest that leaves extract of purslane (1500 ppm) may be used for obtaining reasonable thermal stability of soybean oil with acceptable sensory characteristics of the product. Although TBHQ showed almost similar thermal stability with leaves extract of purslane (1500 ppm), natural anti-oxidant is more preferred over synthetic anti-oxidant.