Characterization of walnut protein isolate-polyphenol nanoconjugates for the developing a food-grade delivery system.

This study investigated the effects of the interaction of walnut protein isolate (WPI) with epigallocatechin gallate (EGCG), chlorogenic acid (CLA), (+)-catechin (CA), and ellagic acid (EA) on the structural and functional properties of proteins. The results for polyphenol binding equivalents and content of free amino and sulfhydryl groups as well as those from sodium dodecyl sulfate‒polyacrylamide gel electrophoresis confirmed the covalent interaction between WPI and the polyphenols. The binding capacities of the WPI-polyphenol mixtures and conjugates were as follows: WPI-EGCG > WPI-CLA > WPI-CA > WPI-EA. Fourier transform infrared spectroscopy (FTIR) and fluorescence spectrum analysis identified changes in the protein structure. The conjugation process obviously increased the polyphenols' antioxidant properties and the surface hydrophobicity was substantially reduced. WPI-EGCG conjugates had the best functional properties, followed by WPI-CLA, WPI-CA, and WPI-EA. Lycopene (LYC) was loaded into nanocarriers by WPI-EGCG self-assembly. These results indicated that WPI-polyphenol conjugates can be utilized to develop food-grade delivery systems to protect chemically lipophilic bioactive compounds. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05768-2.

Comparison of chemical characterization and oxidative stability of Lycium barbarum seed oils: A comprehensive study based on processing methods.

Five different processing methods (cold pressing, hot pressing, solvent extraction, ultrasound-assisted solvent extraction, and supercritical fluid extraction) were evaluated to extract oils from Lycium barbarum (L. barbarum) seeds based on the lipid composition, minor bioactive components, and oxidative stability of oils. A large proportion of unsaturated fatty acids was detected in the L. barbarum seed oil, especially linoleic acid (65.24-66.26%). Minor bioactive components were abundant in L. barbarum seed oils, including tocopherols (292.65-488.49 mg/kg), phytosterols (9606.31-166,684.77 mg/kg), polyphenols (35.65-113.87 mg/kg), and carotenoid (4.17-46.16 mg/100 g). Specifically, the phytosterol content was higher than that of other common oils. Comparing the different processing techniques, ultrasound-assisted solvent extraction provided the highest extraction yield and recovery. The quantities of tocopherols, phenols, and phytosterols in hot-pressed oil were higher than those in oils extracted from other methods, and thus it had the best oxidative stability. L. barbarum seed oils extracted by different techniques showed various characteristics and could be distinguished through principal component analysis and hierarchical cluster analysis. PRACTICAL APPLICATION: L. barbarum seed oil is a potentially underutilized oil resource with abundant essential fatty acid and phytosterol, which owns great value to apply in the nutritional, cosmetic, and medicinal fields. Hot pressing is an efficient method to produce L. barbarum seed oil for health care with high nutritional value and good quality, which can also be easily implemented on an industrial scale.

Effect of oilseed roasting on the quality, flavor and safety of oil: A comprehensive review.

Roasting is widely applied in oil processing and employs high temperatures (90-260 °C) to heat oilseeds evenly. Roasting improves the extraction yield of oil by the generation of pores in the oilseed cell walls, which facilitates the movement of oil from oilseed during subsequent extraction. It also affects the nutritional value and palatability of the prepared oil, which has attracted consumers' attention. An appropriate roasting process contributes to better extraction of bioactive compounds, particularly increasing the total polyphenol content in the oil. Correspondingly, extracted oil exhibits higher antioxidant capacity and oxidative stability after roasting the oilseeds due to better extraction of endogenous antioxidants and the generation of Maillard reaction products. Furthermore, roasting process is critical for the formation of aroma-active volatiles and the improvement of desired sensory characteristics, so it is indispensable for the production of fragrant oil. However, some harmful components are inevitably generated during roasting, including oxidation products, polycyclic aromatic hydrocarbons, and acrylamide. Monitoring and controlling the concentrations of harmful compounds in the oil during the roasting process is important. Therefore, this review updates how roasting affect the quality and safety of oils and provides useful insight into regulation of the roasting process based on bioactive compounds, sensory characteristics, and safety of oils. Further research is required to assess the nutritional value and safety of roasted oils in vivo and to develop a customized roasting process for various oilseeds to produce good-quality oils.

Walnut Polyphenol Extract Protects against Malathion- and Chlorpyrifos-Induced Immunotoxicity by Modulating TLRx-NOX-ROS.

Malathion (MT) and chlorpyrifos (CPF) are immunotoxic organophosphate pesticides that are used extensively in agriculture worldwide. Dietary polyphenols protect against a variety of toxins. In this study, walnut polyphenol extract (WPE) prevents MT- or CPF-induced toxicity to splenic lymphocytes in vitro. WPE promotes the proliferation of MT-exposed splenocytes, as indicated by increases in the proportions of splenic T-lymphocyte subpopulations (CD3+, CD4+, and CD8+ T cells) and levels of T-cell-related cytokines interleukin (IL)-2, interferon-γ, IL-4, and granzyme B, and decreases the apoptosis-associated proteins Bax and p53. WPE also significantly enhances the proliferation of CPF-exposed splenic B lymphocytes (CD19+ B cells) and levels of the B-cell-related cytokine IL-6, leading to decreases of the apoptosis-associated proteins Bax and p53. These effects are related to reduced production of reactive oxygen species (ROS), as evidenced by normalized hydroxyl radical (•OH), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and glutathione (GSH) levels, which are associated with decreased expression of NADPH oxidase 2 (NOX2) and dual oxidase 1 (DUOX1). WPE inhibits the production of ROS and expression of NOX by regulating toll-like receptors 4 and 7 in MT- and CPF-exposed splenic lymphocytes. In conclusion, WPE protects against MT- or CPF-mediated immunotoxicity and inhibits oxidative damage by modulating toll-like receptor (TLR)x-NOX-ROS.

Effect of Roasting Temperatures on the Properties of Bitter Apricot (Armeniaca sibirica L.) Kernel Oil.

Volatile compounds and quality changes of bitter apricot (Armeniaca sibirica L.) kernel oil (AKO) with different roasting conditions were determined. Bitter apricot kernels were roasted at 120, 130, 140 and 150°C for 15 min. Unroasted bitter apricot kernel oil was used as the control. Quality indicators included color, acid value and peroxide value, fatty acids, total phenols and oxidative stability. Peroxide values of the tested oils were 0.46-0.82 meq/kg, acid values were 0.60-1.40 mg KOH/g, and total phenol contents were 54.1-71.5 µg GAE/g. Oleic acid was the major fatty acid, followed by linoleic, palmitic, stearic and palmitoleic acids. Roasting increased the oxidative stability of bitter AKO. Volatile compounds were tentatively identified and semi-quantified. Among the 53 volatiles identified, benzaldehyde and benzyl alcohol were the major components. These two aroma compounds increased significantly during roasting and contributed sweet and almond flavors. Pyrazines were also prevalent and significantly increased with roasting. Sensory evaluation showed that roasted, nutty, sweet and oily aromas increased as roasting temperature increased.Practical applications: Bitter apricot kernels cannot be consumed directly, thus it is potentially beneficial to find uses for them, especially in China where bitter apricot processing is a significant industry. Roasted bitter AKO with a pleasant aroma could be prepared and might find use as an edible oil. The roasting process gave the bitter AKO a pleasant flavor. This study provided preliminary information on production parameters and potential quality control parameters.

Purification and structural characterization of an α-glucosidase inhibitory polysaccharide from apricot (Armeniaca sibirica L. Lam.) pulp.

In this study, the crude polysaccharide (APPS) from the fruiting bodies of apricot (Armeniaca sibirica L. Lam.) was isolated and fractionated by ultrafiltration and Sephadex G-75 gel chromatography. The hypoglycemic activities of all fractions were determined by α-glucosidase inhibitory activity in vitro. The fraction APPS1-2 showed the best activity with an IC50 of 6.06 mg/mL. The properties and chemical compositions of this fraction were analyzed with high-performance liquid chromatography, gel permeation chromatography-eighteen angle laser light scattering instrument, UV spectroscopy, infrared spectroscopy, and NMR spectroscopy ((1)H). The results demonstrated that APPS1-2 was a neutral glycoconjugate with a molecular weight of 25.93 kDa. It comprised rhamnose, glucose, mannose, and galactose, with a relative molar ratio of 1.34:2.01:0.48:0.35. The backbone of APPS1-2 may consist of rhamnose and glucose, but its branches may consist of mannose and galactose. The IR and UV spectrum of APPS1-2 revealed the typical characteristics of heteropolysaccharide. (1)H NMR spectrum showed that APPS1-2 contained α-configurations.

Hydroxytyrosol, a natural molecule from olive oil, suppresses the growth of human hepatocellular carcinoma cells via inactivating AKT and nuclear factor-kappa B pathways.

The present study aimed to investigate the anti-cancer effects of hydroxytyrosol (HT) in human hepatocellular carcinoma (HCC) cells. Our results show that HT could inhibit proliferation, induce G2/M cell cycle arrest and apoptosis in human HCC cells. Mechanically, we found that HT could suppress the activation of AKT and nuclear factor-kappa B (NF-κB) pathways. HT also significantly inhibited the tumor growth, angiogenesis and the activation of AKT and NF-κB pathways in an orthotopic model of human HCC in vivo. These data suggest that HT may be a promising candidate agent for the treatment of HCC.

[Effects of panthenol-glutamine on intestine of rats with burn injury and its dose-effect relationship].

OBJECTIVE: To study the effects of the panthenol-glutamine on intestinal damage and motor function of intestine in rats with burn injury as well as its dose-effect relationship. METHODS: (1) Experiment 1. Ninety SD rats were divided into groups A-I according to the random number table, with 10 rats in each group. Rats in groups A-I were inflicted with 30% TBSA full-thickness burn and fed by gavage with panthenol and glutamine at post injury hour (PIH) 4, in the whole dosage of 1.00 and 4, 0.50 and 4, 0.25 and 4, 1.00 and 2, 0.50 and 2, 0.25 and 2, 1.00 and 1, 0.50 and 1, 0.25 and 1 g·kg(-1)·d(-1). The feeding was carried out twice a day to achieve the total dosage in 7 days. On drug withdrawal day, blood and intestinal tissue were harvested to detect the intestinal propulsion index, diamine oxidase (DAO) activity in serum, and the content of acetylcholine and intestinal mucosa protein. The best proportion of panthenol and glutamine was screened. (2) Experiment 2. Seventy SD rats were divided into normal control (NC), burn (B), burn+panthenol (B+P), burn+glutamine (B+G), and burn+low, moderate, or high dose of panthenol-glutamine (B+LPG, B+MPG, B+HPG) groups according to the random number table, with 10 rats in each group. Rats in the latter 6 groups were inflicted with 30% TBSA full-thickness burn. Rats in the latter 5 groups were fed by gavage with panthenol and (or) glutamine at PIH 4. Rats in group B+P were fed with panthenol for 1 g·kg(-1)·d(-1), rats in group B+G with glutamine for 4 g·kg(-1)·d(-1), rats in groups B+LPG, B+MPG, and B+HPG with panthenol and glutamine in the dosage of 0.50 and 2, 1.00 and 4, 2.00 and 8 g·kg(-1)·d(-1). The feeding was carried out twice a day to achieve the total dosage for 7 days. The indexes and time point for observation were the same as those of experiment 1. Meanwhile, the pathological change in intestine was observed. The same process was carried out in the rats of group NC. Data were processed with factorial designed analysis of variance (ANOVA), one-way ANOVA and Fisher's exact probability test. LSD was applied for paired comparison. RESULTS: (1) The values of intestinal propulsion index and intestinal mucosa protein content in groups A and B were close (with P values all above 0.05), and were significantly higher than those of the other 7 groups (with P values all below 0.01). Content of acetylcholine in group A was significantly higher than that of the other 8 groups (with P values all below 0.01). DAO activity in groups A, D, and E was close in value (with P values all above 0.05), and all of the values were significantly lower than those of the other 6 groups (with P values all below 0.01). The best proportion of panthenol and glutamine was 1.00 and 4 g·kg(-1)·d(-1). (2) Compared with those of group NC, the intestinal propulsion index, the contents of acetylcholine and intestinal mucosa protein were decreased significantly, while the DAO activity obviously increased in group B (with P values all below 0.01); the intestinal propulsion index was decreased significantly in group B+P (P < 0.01); the intestinal propulsion index and content of acetylcholine were decreased significantly in group B+G (with P values all below 0.01); the intestinal propulsion index was decreased significantly in group B+LPG (P < 0.01); no obvious change was observed in groups B+MPG and B+HPG (with P values all above 0.05). Compared with those of group B [0.50 ± 0.07, (69 ± 10) µg/mL, (26 ± 11) µg/g, (0.672 ± 0.145) U/mL], the contents of acetylcholine and intestinal mucosa protein were increased significantly, DAO activity decreased significantly in group B+P (with P values all below 0.01); the contents of intestinal mucosa protein was increased significantly, DAO activity decreased significantly in group B+G (with P values all below 0.01); the contents of acetylcholine and intestinal mucosa protein were increased significantly in group B+LPG (with P values all below 0.01); the intestinal propulsion index, the contents of acetylcholine and intestinal mucosa protein were increased significantly, while the DAO activity obviously decreased in groups B+MPG and B+HPG [0.66 ± 0.07, 0.68 ± 0.05; (163 ± 24), (168 ± 15) µg/mL; (57 ± 7), (57 ± 7) µg/g; (0.203 ± 0.070), (0.193 ± 0.068) U/mL, with P values all below 0.01]. The levels of the four indexes in groups B+MPG and B+HPG were close or the same in values (with P values all above 0.05). Compared with those of group B, the numbers of rats with irregularly arranged villi in group B+P were decreased significantly (P < 0.05); the numbers of rats with villi decreased in height, irregularly arranged villi, and neutrophil infiltration in group B+G were decreased significantly (with P values all below 0.05); the numbers of rats with villi decreased in height, irregularly arranged villi, degeneration and necrosis of cells, and neutrophil infiltration in group B+LPG were decreased significantly (with P values all below 0.05); the numbers of rats with villi decreased in height and number, irregularly arranged villi, degeneration and necrosis of cells, and neutrophil infiltration in groups B+MPG and B+HPG were decreased significantly (with P values all below 0.05). There was no statistically significant difference between group B+HPG and group B+MPG for the former mentioned five indexes (with P values all above 0.05). CONCLUSIONS: Combined application of panthenol and glutamine can obviously reduce intestinal mucosa damage and promote gastrointestinal motility of rats with burn injury, and they show curative effect superior to exclusive use of either of the two drugs. The best proportion of panthenol and glutamine is 1.00 and 4 g·kg(-1)·d(-1).

[Role of corticotropin releasing factor receptor 2 antisense oligodeoxynucleotide of hypothalamus in hypermetabolism in rats with severe burn].

OBJECTIVE: To observe the role of corticotropin releasing factor receptor 2 antisense oligodeoxynucleotide (CRFR2ASO) of hypothalamus in hypermetabolism in rats with severe burn. METHODS: Stainless-steel cannula were implanted into the 3rd ventricle. According to different medicine delivered into the 3rd ventricle, 30 SD rats with 30% TBSA full-thickness burn were divided randomly into burn control group (BC, with injection of 3 microL saline), CRFR1ODN group (with injection of CRFR1ODN 10 microg), CRFR1ASO group (with injection of CRFR1ASO 10 microg), CRFR2ODN group(with injection of CRFR2ODN 10 microg), CRFR2ASO group (with injection of CRFR2ASO 10 microg), with 6 rats in each group. Another 6 rats served as normal control (NC) and they received isotonic saline 3 microL instead. Different medicines were respectively delivered into respective group on 5, 6 post injury day (PID), then 3 microL gentian violet was introduced on 7 PID. Resting energy expenditure (REE) value and the expression level of hypothalamus CRFR2mRNA and CRFR2 protein were determined. RESULTS: REE value in BC, CRFR1ODN, CRFR1ASO, CRFR2ODN, CRFR2ASO groups was 11 840 +/- 987, 11 133 +/- 1100, 10 733 +/- 1338, 11 123 +/- 1321, 7563 +/- 890 kJx(m2)(-1)xd(-1), respectively, which were obviously higher than that in BC group [6641 +/- 526 kJx(m2)(-1)xd(-1), P < 0.05]. REE value in CRFR2ASO group was obviously lower than that in CRFR2ODN group (P < 0.01). The expression level of hypothalamus CRFR2 mRNA and its protein in BC group were increased after burn, which were obviously lower in CRFR2ASO group than NC group (P < 0.01). CONCLUSION: Central application of CRFR2ASO can downregulate the expression level of hypothalamus CRFR2 mRNA and its protein, and reduce hypermetabolism. Hypothalamus CRFR2 may mediate hypermetabolism in burn rats.