Showing papers by "Ministry of Agriculture published in 2022"

Entrapment of curcumin in soy protein isolate using the pH-driven method: Nanoencapsulation and formation mechanism

Abstract: The use of curcumin in the food industry is constrained by its poor aqueous dispersibility and instability. Previous studies have shown that stable curcumin nanoparticles can be prepared using a pH-driven method. In this study, the nanoencapsulation of curcumin by soybean protein isolate (SPI) was achieved using the pH-driven method. The effect of final pH on SPI and SPI-curcumin (SPI-Cur) nanocomposites was determined by analyzing the encapsulation efficiency and stability. SPI had a high encapsulation efficiency for curcumin and was stable, especially at pH 7 and 8. The formation mechanisms of SPI and SPI-Cur were further determined by molecular docking and multispectral analyses. The results showed that hydrogen bond acceptors (O−) of curcumin under alkaline media interacted with the donor groups (N–H) of amino acids to form hydrogen bonds. Throughout the process, hydrophobic interactions promoted the formation of the nanocomposites, and curcumin had a strong static fluorescence quenching effect on SPI. Furthermore, CD spectroscopy demonstrated that the pH-driven method altered the secondary structure of the SPI. This study provides evidence for the interaction mechanism between curcumin and SPI at different pH-driven stages and indicates SPI-Cur can be used as a delivery system of hydrophobic nutraceuticals.

Melatonin improves the quality of maternally aged oocytes by maintaining intercellular communication and antioxidant metabolite supply

Abstract: In mammalian ovaries, oocytes are physically coupled to somatic granulosa cells, and this coupling is crucial for the growth and development of competent oocytes as it mediates the transfer of metabolic support molecules. However, aging-mediated dysregulation in communication between the oocytes and granulosa cells affects the oocyte quality. In the present study, we examined the defected germline-soma communication and reduced mRNA levels encoding key structural components of transzonal projections (TZPs) in maternally aged oocytes. Oral administration of melatonin to aged mice substantially increased TZPs and maintained the cumulus cells-oocyte communication, which played a central role in the production of adequate oocyte ATP levels and reducing the accumulation of reactive oxygen species (ROS), apoptosis, DNA damage, endoplasmic reticulum (ER) stress and spindle/chromosomal defects. This beneficial effect of melatonin was inhibited by carbenoxolone (CBX), a gap junctional uncoupler, which disrupts bidirectional communications between oocyte and somatic cells. Simultaneously, melatonin significantly increased the mRNA and protein levels corresponding to genes associated with TZPs and prevented TZP retraction in in vitro-cultured cumulus-oocyte complex (COCs). Furthermore, we infused melatonin and CBX into the COCs in vitro culture system and monitored the levels of nicotinamide adenine dinucleotide phosphate (NADPH) and glutathione (GSH) in cumulus cells and oocytes. Notably, COCs treated with melatonin demonstrated improved NADPH and GSH levels. Of note, CBX was capable of reducing NADPH and GSH levels, aggravated the ROS accumulation and ER stress. Collectively, our data demonstrate the role of melatonin in preventing age-associated germline-soma communication defects, aiding the relay of antioxidant metabolic molecules for the maintenance of oocyte quality from cumulus cells, which have important potential for improving deficient phenotypes of maternally aged oocytes and the treatment of woman infertility.

Entrapment of curcumin in soy protein isolate using the pH-driven method: Nanoencapsulation and formation mechanism

Abstract: The use of curcumin in the food industry is constrained by its poor aqueous dispersibility and instability. Previous studies have shown that stable curcumin nanoparticles can be prepared using a pH-driven method. In this study, the nanoencapsulation of curcumin by soybean protein isolate (SPI) was achieved using the pH-driven method. The effect of final pH on SPI and SPI-curcumin (SPI-Cur) nanocomposites was determined by analyzing the encapsulation efficiency and stability. SPI had a high encapsulation efficiency for curcumin and was stable, especially at pH 7 and 8. The formation mechanisms of SPI and SPI-Cur were further determined by molecular docking and multispectral analyses. The results showed that hydrogen bond acceptors (O − ) of curcumin under alkaline media interacted with the donor groups (N–H) of amino acids to form hydrogen bonds. Throughout the process, hydrophobic interactions promoted the formation of the nanocomposites, and curcumin had a strong static fluorescence quenching effect on SPI. Furthermore, CD spectroscopy demonstrated that the pH-driven method altered the secondary structure of the SPI. This study provides evidence for the interaction mechanism between curcumin and SPI at different pH-driven stages and indicates SPI-Cur can be used as a delivery system of hydrophobic nutraceuticals. • Stable SPI-Cur nanocomposites were prepared with high encapsulation efficiency. • The final pH value affected the properties of nanocomposites. • Mainly hydrogen bonds and hydrophobic interactions exist in the pH-driven method. • The interaction was altered by structural changes at different pH-driven stages.

Profiling of dynamic changes in non-volatile metabolites of shaken black tea during the manufacturing process using targeted and non-targeted metabolomics analysis

Abstract: Shaken black tea (SBT) is a new type of black tea that combines the traditional black tea processing technology with the shaking process of oolong tea. In this study, non-targeted metabolomics analysis based on ultra-high-pressure liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) was applied to comprehensively analyze the non-volatile metabolites of SBT during the manufacturing process. Using multivariate statistical analysis, 93 compounds were screened as differential compounds. During the whole process of SBT, amino acids, dipeptides, theaflavins and lipids contents showed significant increases, while that of catechins and procyanidin C1 significantly decreased. Compared with fresh leaves, the content of proteinaceous amino acids (PAAs) in the dried black tea increased 1.61-fold, and total catechins decreased to 7.25%. The results of hierarchical clustering analysis (HCA) showed that fermentation is the key process that causes the variations of these metabolites, followed by drying and shaking. The biosynthesis metabolism of amino acids, flavonoids and linoleic acid are abundant, mainly due to the stress response of fresh tea leaves to dehydration and mechanical damage during shaking processing. It is beneficial to explore the quality formation during the production of SBT through comprehensive analysis of the changes in metabolites.

Hydrothermal, KOH-assisted synthesis of lignin-derived porous carbon for supercapacitors: value-added of lignin and constructing texture properties/specific capacitance relationships

Abstract: Searching for good-natured feedstocks and understanding the texture property of porous carbon/specific capacitance relationships have long been highly desirable. Herein, hydrothermal and KOH were used to assist the synthesis of lignin-derived porous carbons (LPCs) with high specific surface area for supercapacitors. The as-synthesized LPC-150 and LPC-200 had a specific surface area of 3033.88 m2/g and 3178.36 m2/g, respectively, with a specific capacitance of 214.03 F/g and 201.69 F/g at 0.50 A/g. In the range from 2448 m2/g to 3178 m2/g, increasing the specific surface area again possesses no remarkable effect on the specific capacitance. Meanwhile, the specific surface area and the pore-wall thickness together determine the specific capacitance. When using a three-electrode configuration with a 6 mol/L KOH electrolyte, the volumetric surface area rather than the ultrahigh specific surface area can be employed as a general predictor of specific capacitance in the low current density ranging from 0.50 to 10.00 A/g.

Effective prediction of biosynthetic pathway genes involved in bioactive polyphyllins in Paris polyphylla

Abstract: The genes in polyphyllins pathway mixed with other steroid biosynthetic genes form an extremely complex biosynthetic network in Paris polyphylla with a giant genome. The lack of genomic data and tissue specificity causes the study of the biosynthetic pathway notably difficult. Here, we report an effective method for the prediction of key genes of polyphyllin biosynthesis. Full-length transcriptome from eight different organs via hybrid sequencing of next generation sequencingand third generation sequencing platforms annotated two 2,3-oxidosqualene cyclases (OSCs), 216 cytochrome P450s (CYPs), and 199 UDP glycosyltransferases (UGTs). Combining metabolic differences, gene-weighted co-expression network analysis, and phylogenetic trees, the candidate ranges of OSC, CYP, and UGT genes were further narrowed down to 2, 15, and 24, respectively. Beside the three previously characterized CYPs, we identified the OSC involved in the synthesis of cycloartenol and the UGT (PpUGT73CR1) at the C-3 position of diosgenin and pennogenin in P. polyphylla. This study provides an idea for the investigation of gene cluster deficiency biosynthesis pathways in medicinal plants.