Kinetics of the thermal degradation of phenolic compounds from achiote leaves (Bixa orellana L.) and its effect on the antioxidant activity

Antioxidant and UV-blocking activity of PVA/tannin-based bioplastics in food packaging application

In this study, bioplastics with antioxidant and UV protection properties based on tannin and PVA were created for packaging uses. Using a hot water extraction method at various extraction temperatures (60-100 °C), tannins were removed from the bark of Acacia mangium. Tannins with the best antioxidant activity were extracted at 80 °C. In order to create bioplastic formulations (PVA/Tannins), the extract is then employed. The non-heating bioplastic method's preparation (M3) stage produced the highest levels of antioxidant activity. Therefore, subsequent tests were conducted using the non-heating method (M3). On the opacity, UV protective activity, antioxidant capacity, mechanical strength, thermal stability, and water vapor permeability of the resultant bioplastics, the impact of tannin concentration (0.1-0.5 g) was examined. The findings of the experiments demonstrate that PVA/Tannin bioplastics are less transparent than pure PVA. The PVA/tannin bioplastics that are formed, on the whole, show strong antioxidant and UV protection action. Comparing PVA/Tannin bioplastics to pure PVA also revealed a small improvement in thermal stability and tensile strength. In PVA bioplastics with resistant tannins, moisture content was marginally greater even at low tannin concentrations (0.1 g). Based on the findings, bioplastics made from PVA and the tannin A. mangium have the potential to be used to create packaging that is UV and active antioxidant resistant. It can be applied as the second (inner) layer of the primary packaging to protect food freshness and nutrition due to their antioxidant activity.

Production and characterization of Ziziphus jujuba extract-loaded composite whey protein and pea protein beads based on sodium alginate-IFPG (insoluble fraction of Persian gum)

BACKGROUND

This research was aimed at the fabrication of jujube extract (JE)-loaded beads by extrusion, using whey protein isolate (WPI), chickpea protein concentrate (PPC) and a combination of two types of hydrocolloid insoluble fraction of Persian gum (IFPG) and sodium alginate (Al).

RESULTS

JE-loaded beads with the highest encapsulation efficiency (10.87%) and polyphenol content (120.8 mg L^-1 gallic acid) were obtained using Al-IFPG/PPC at 4 °C. The Al-IFPG, Al-IFPG/WPI and Al-IFPG/PPC beads revealed 5.66, 6.85 and 5.76 mm bead size, respectively, and almost all of them demonstrated a homogeneous and spherical structure. Fourier transform infrared spectroscopy data proved that the stable structure of the Al-IFPG beads was due to hydrogen bonding and electrostatic interactions. The thermostability of beads loaded with JE based on Al-IFPG/WPI was significantly enhanced compared to pure Al-IFPG. Texture evaluation of JE-loaded beads based on Al-IFPG incorporation with WPI revealed an increment in the hardness of beads.

CONCLUSION

This study confirmed the potential of Al-IFPG complex beads for the effective delivery of jujube extract via incorporation into pea and whey proteins and for the expansion of its use in products. © 2023 Society of Chemical Industry.

Characterization of entrapment behavior of polyphenols in nanostructured lipid carriers and its effect on their antioxidative activity

Polyphenols are widely used as antioxidant agents to protect human health. Resveratrol, kaempferol, and quercetin have been reported to have potent antioxidant activity; however, these compounds have many problems related to their practical application, such as instability and insolubility. Thus, a nanostructured lipid carrier (NLC) was utilized as a drug delivery system (DDS) to overcome these limitations. This study investigated the particle stability, drug loading performance, and antioxidant activity of polyphenols-incorporated NLCs. The particle size and distribution were suitable for DDS applications, and all the samples demonstrated good stability after 2 months of storage. Based on Raman spectroscopy analysis, polyphenols were successfully encapsulated in NLCs. Quantitative high-performance liquid chromatography analysis indicated that NLCs could load resveratrol more than kaempferol and quercetin. In addition, NLCs have successfully improved all the antioxidant activity per unit concentration of polyphenol (specific antioxidant activity) compared to the free polyphenols. Quercetin-incorporated NLCs showed the highest specific antioxidant activity. This result is the opposite of entrapment efficiency and actual antioxidant activity, most likely influenced by the location of entrapped polyphenol molecules. As it was performed, NLCs are highly recommended to be applied as an antioxidant delivery system.

Impact of the Cooking Process on Metabolite Profiling of Acanthocereus tetragonus, a Plant Traditionally Consumed in Mexico

Acanthocereus tetragonus (L.) Hummelinck is used as an alternative food source in some Mexican communities. It has been shown that the young stems of A. tetragonus provide crude protein, fiber, and essential minerals for humans. In this work, we analyzed the phytochemical profile, the total phenolic content (TPC), and the antioxidant activity of cooked and crude samples of A. tetragonus to assess its functional metabolite contribution to humans. The phytochemical profile was analyzed using Ultra-High-Performance Liquid Chromatography coupled to High-Resolution Mass Spectrometry (UHPLC-PDA-HESI-Orbitrap-MS/MS). Under the proposed conditions, 35 metabolites were separated and tentatively identified. Of the separated metabolites, 16 occurred exclusively in cooked samples, 6 in crude samples, and 9 in both crude and cooked samples. Among the detected compounds, carboxylic acids, such as threonic, citric, and malic acids, phenolic acids, and glycosylated flavonoids (luteolin-O-rutinoside) were detected. The TPC and antioxidant activity were analyzed using the Folin–Ciocalteu method and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical inhibition method, respectively. The TPC and antioxidant activity were significantly reduced in the cooked samples. We found that some metabolites remained intact after the cooking process, suggesting that A. tetragonus represents a source of functional metabolites for people who consume this plant species.