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1.
Org Lett ; 26(18): 3767-3771, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38664947

ABSTRACT

A copper-catalyzed efficient regioselective silylation reaction of chloro-substituted allenyl-Bdan was developed. Under mild reaction conditions, allenyl and propargyl silane compounds can be selectively obtained in moderate to high yields by adjusting the bases and solvents used in the reactions. This study offers direct and efficient methods for synthesizing multifunctionalized allenyl and propargyl silane compounds from the same initial material of chloro-substituted allenyl-Bdan.

2.
Angew Chem Int Ed Engl ; 63(25): e202405791, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38593214

ABSTRACT

Herein, we present catalyst-regulated switchable site-selective hydrosilylation of enynes, which are suitable for a wide range of alkyl and aryl substituted polar enynes and exhibit excellent functional group compatibility. Under the optimized conditions, silyl groups can be precisely installed at various positions of 1,3-dienes. While α- and γ-silylation products were obtained under platinum-catalytic systems, ß-silylation products were delivered with [Cp*RuCl]4 as catalyst. This process lead to the formation of 1,3-dienoates with diverse substitutions, which would pose challenges with other methodologies.

3.
Glob Chall ; 8(2): 2300032, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38356680

ABSTRACT

Flexible thin-film thermoelectric devices (TEDs) can generate electricity from the heat emitted by the human body, which holds great promise for use in energy supply and biomonitoring technologies. The p-type Sb2Te3 hexagon nanosheets are prepared by the hydrothermal synthesis method and compounded with Ti3C2Tx to make composite films, and the results show that the Ti3C2Tx content has a significant impact on the thermoelectric properties of the composite films. When the Ti3C2Tx content is 2 wt%, the power factor of the composite film reaches ≈59 µW m-1 K-2. Due to the outstanding electrical conductivity, high specific surface area, and excellent flexibility of Ti3C2Tx, the composite films also exhibit excellent thermoelectric and mechanical properties. Moreover, the small addition of Ti3C2Tx has a negligible effect on the phase composition of Sb2Te3 films. The TED consists of seven legs with an output voltage of 45 mV at ΔT = 30 K. The potential of highly flexible thin film TEDs for wearable energy collecting and sensing is great.

4.
World J Microbiol Biotechnol ; 40(2): 53, 2023 Dec 26.
Article in English | MEDLINE | ID: mdl-38146044

ABSTRACT

Fermentation is considered an effective tool for improving the functional characteristics of food. In this study, Lacticaseibacillus casei YQ336 was used to ferment yellow whey, and physical and chemical analysis was performed to identify the changes in the nutritional components and antioxidant activity of the fermented yellow whey. Non-targeted metabolomics was used to study the transformation of small molecular substances in the fermented yellow whey. After 48 h of pure culture fermentation with L. casei YQ336, the pH of yellow whey decreased significantly (p < 0.05). Meanwhile, the content of total acids, organic acids, sugars, total phenols, and total flavonoids and the antioxidant activity showed a significant increase (p < 0.05). A total of 628 differential metabolites were identified between fermented and unfermented yellow whey samples, of which 293 were upregulated and 335 were downregulated. After fermentation, due to the growth and metabolic activity of L. casei YQ336, meaningful metabolites such as homovanillic acid, lactic acid, oxalic acid, L-glutamic acid, and phenylalanine, as well as phenyllactic acid, gallic acid, and genistein were produced. This increased the organic acid content and antioxidant activity of yellow whey. The findings provide a theoretical and practical basis for further research on the bio-functional activity of yellow whey and the recycling and utilization of food by-products.


Subject(s)
Lacticaseibacillus casei , Whey , Whey/metabolism , Antioxidants/metabolism , Fermentation , Whey Proteins/metabolism , Acids/metabolism , Lactic Acid/metabolism
5.
Front Microbiol ; 14: 1274353, 2023.
Article in English | MEDLINE | ID: mdl-38029167

ABSTRACT

Introduction: Ganmai Dazao Decoction is a traditional Chinese recipe, and is composed of licorice, floating wheat, and jujube. Methods: Effects of lactic acid bacteria fermentation on the physicochemical properties, antioxidant activity, and γ-aminobutyric acid of Ganmai Dazao Decoction were studied. The changes of small and medium molecules in Ganmai Dazao Decoction before and after fermentation were determined by LC-MS non-targeted metabolomics. Results: The results showed that the contents of lactic acid, citric acid, acetic acid, and total phenol content increased significantly, DPPH free radical clearance and hydroxyl free radical clearance were significantly increased. γ-aminobutyric acid content was 12.06% higher after fermentation than before fermentation. A total of 553 differential metabolites were detected and identified from the Ganmai Dazao Decoction before and after fermentation by partial least squares discrimination and VIP analysis. Discussion: Among the top 30 differential metabolites with VIP values, the content of five functional substances increased significantly. Our results showed that lactic acid bacteria fermentation of Ganmai Dazao Decoction improves its antioxidant effects and that fermentation of Ganmai Dazao Decoction with lactic acid bacteria is an innovative approach that improves the health-promoting ingredients of Ganmai Dazao Decoction.

6.
Food Res Int ; 174(Pt 1): 113547, 2023 12.
Article in English | MEDLINE | ID: mdl-37986427

ABSTRACT

Lactic acid bacteria (LAB) fermentation is frequently employed to improve the nutritional, functional, and sensory characteristics of foods. Our study explored the effects of co-fermentation with Lacticaseibacillus paracasei ZH8 and Lactococcus lactis subsp. lactis YM313 on the physicochemical properties, antioxidant activity, and metabolomic profiles of wolfberry-longan juice (WLJ). Fermentation was carried out at 35 °C for 15 h. The results suggest that WLJ is a favorable substrate for LAB growth, reaching a total viable count exceeding 8 log CFU/mL after fermentation. LAB fermentation increased acidity, reduced the sugar content, and significantly impacted the juice color. The total phenolic and flavonoid contents of the WLJ and the antioxidant capacities based on 2,2-diphenyl-1-picrylhydrazyl (DPPH), ABTS radical scavenging abilities and FRAP were significantly improved by LAB fermentation. Nontargeted metabolomics analysis suggested that the contents of small molecule substances in WLJ were considerably affected by LAB fermentation. A total of 374 differential metabolites were identified in the juice before and after fermentation, with 193 significantly upregulated metabolites and 181 siginificantly downregulated metabolites. The regulation of metabolites is important for improving the flavor and functions of juices, such as L-eucylproline, Isovitexin, Netivudine, 3-Phenyllactic acid, vanillin, and ethyl maltol, ect. This study provides a theoretical foundation for developing plant-based foods fermented with LAB.


Subject(s)
Lactobacillales , Lycium , Lactobacillales/metabolism , Antioxidants/analysis , Fermentation , Fruit and Vegetable Juices/analysis
7.
Org Lett ; 25(40): 7332-7337, 2023 Oct 13.
Article in English | MEDLINE | ID: mdl-37782771

ABSTRACT

We develop a copper-catalyzed disilylation of polysubstituted pent-1-en-4-yn-3-yl acetate derivatives, which in one pot furnishes the bis(silyl)-substituted vinylallenes in moderate yields under mild reaction conditions. The reaction shows broad substrate scope and single stereoselectivity. Besides, we develop a method to decrease the electrocyclization temperature of vinylallenes for the synthesis of methylenecyclobutenes by installing bis(silyl) substituents. And the effect of a silyl substituent on electrocyclization of vinylallenes was studied via DFT computation. The synthetic method features broad substrate scope and excellent stereoselectivity.

8.
Front Microbiol ; 14: 1152654, 2023.
Article in English | MEDLINE | ID: mdl-37533834

ABSTRACT

The ancient traditional Chinese drink Bian-Que Triple-Bean Soup made by fermentation (FTBS) of Lactococcus lactis subsp. lactis YM313 and Lacticaseibacillus casei YQ336 is a potential functional drink. The effect of fermentation on the flavor and biological activity of FTBS was evaluated by analyzing its chemical composition. Five volatile flavors were detected in modified FTBS. Fermentation decreased the proportion of nonanal (beany flavor substances) but significantly increased the total flavone contents, phenol contents and many bioactive small molecule substances in FTBS. The changes of these substances led to the significant improvement of FTBS sensory evaluation, antioxidant activity and prebiotic potential. This research provides a theoretical basis for the application of Lactic acid bacteria (LAB) in the fermentation of edible plant-based foods and transformation from traditional food to industrial production.

9.
Nat Commun ; 14(1): 5048, 2023 Aug 19.
Article in English | MEDLINE | ID: mdl-37598226

ABSTRACT

We report a copper-catalyzed ligand-controlled selective 1,2- and 1,4-hydrosilylation of 1,3-enynes, which furnishes enantiomerically enriched propargyl- and 1,2-allenylsilane products in high yields with excellent enantioselectivities (up to 99% ee). This reaction proceeds under mild conditions, shows broad substrate scope for both 1,3-enynes and trihydrosilanes, and displays excellent regioselectivities. Mechanistic studies based on deuterium-labeling reactions and density functional theory (DFT) calculations suggest that allenylcopper is the dominant reactive intermediate under both 1,2- and 1,4-hydrosilylation conditions, and it undergoes metathesis with silanes via selective four-membered or six-membered transition state, depending on the nature of the ligand. The weak interactions between the ligands and the reacting partners are found to be the key controlling factor for the observed regioselectivity switch. The origin of high enantiocontrol in the 1,4-hydrosilylation is also revealed by high level DLPNO-CCSD(T) calculations.

10.
J Anim Sci ; 1012023 Jan 03.
Article in English | MEDLINE | ID: mdl-37478469

ABSTRACT

In this study, we investigated 18 healthy and fertile Duroc boars, dividing them into two groups based on their reproductive age: 9 boars aged 18 mo and 9 boars aged 36 mo. Prior to semen sampling, all boars were raised together under identical management conditions for a period of 3 mo. Our findings revealed that older boars exhibited lower sperm motility and a higher proportion of abnormal sperm morphology compared to younger boars. Furthermore, older boars demonstrated lower anti-oxidant capacity in their semen, as indicated by elevated levels of malondialdehyde and decreased levels of superoxide dismutase and glutathione peroxidase. Microbiota analysis utilizing the 16S rRNA technique showed that the semen microbiota of older boars had reduced alpha-diversity and beta-diversity in comparison to younger boars. We identified the Streptococcus genus and Streptococcus gallolyticus subsp macedonicus species served as biomarkers for semen from younger breeding boars, while the Bacteroides pyogenes species as a biomarker for semen from older breeding boars. Additionally, the semen from older boars exhibited a higher abundance of Aerococcus, Gallicola, Ulvibacter, and Proteiniphilum compared to younger boars. Spearman correlation analysis showed that these four bacteria were negatively correlated with semen quality. The abundance of Gallicola and Proteiniphilum were negatively correlated with semen anti-oxidant capacity. Additionally, the reduction of semen anti-oxidant capacity was correlated to the decrease of semen quality. Based on these findings, we concluded that the semen of older boars contains a higher abundance of harmful bacteria, which contributes to the observed reduction in semen anti-oxidant capacity and overall semen quality in this group.


In modern swine husbandry, the culling of breeding boars with low semen quality is a common practice to ensure high reproductive performance. It is widely acknowledged that semen quality tends to decline as boars age. Moreover, recent advances in microbiota analysis have provided evidence that semen is not sterile, suggesting that the composition of semen microbiota may vary among boars of different reproductive ages. These variations in microbiota have the potential to impact semen anti-oxidant capacity and therefore affect semen quality. Therefore, the main objective of this study was to compare the differences in semen quality, semen anti-oxidant capacity, and semen microbiota among boars at various stages of reproductive age. The findings of this study demonstrated an increased abundance of harmful bacteria in the semen of older boars, which is responsible for the observed reduction in semen anti-oxidant capacity and overall semen quality.


Subject(s)
Semen Analysis , Semen , Swine , Male , Animals , Semen Analysis/veterinary , Antioxidants , RNA, Ribosomal, 16S/genetics , Sperm Motility , Spermatozoa
11.
Org Lett ; 25(28): 5242-5247, 2023 Jul 21.
Article in English | MEDLINE | ID: mdl-37418590

ABSTRACT

In this protocol, a copper-catalyzed desymmetric protosilylation of prochiral diynes was developed. The corresponding products were obtained in moderate to high yields and enantiomeric ratios. This approach provides a simple method for synthesizing functionalized chiral tertiary alcohols in the presence of a chiral pyridine-bisimidazoline (Pybim) ligand.

12.
Org Lett ; 25(24): 4498-4503, 2023 Jun 23.
Article in English | MEDLINE | ID: mdl-37289963

ABSTRACT

The three-component coupling method for regio- and stereoselective difunctionalization of allenes with allenyl ethers, bis(pinacolato)diboron, and gem-dichlorocyclobutenones as electrophiles was reported, yielding a variety of highly functionalized cyclobutenone products tethering with an alkenylborate fragment. The polysubstituted cyclobutenone products also underwent diverse transformations.


Subject(s)
Copper , Ethers , Catalysis , Stereoisomerism
13.
Org Lett ; 25(19): 3364-3368, 2023 May 19.
Article in English | MEDLINE | ID: mdl-37154506

ABSTRACT

We report copper-catalyzed borylation and silylation of dichlorocyclobutenones, which furnish the boron-substituted and silicon-substituted polyfunctionalized cyclobutenones in high yields. The reactions proceed under mild reaction conditions, show broad substrate scope, and display high chemoselectivity. In addition, a series of transformations of the corresponding products has been realized.

14.
Odontology ; 111(4): 870-882, 2023 Oct.
Article in English | MEDLINE | ID: mdl-36879181

ABSTRACT

Periodontal tissue regeneration engineering based on human periodontal ligament stem cells (hPDLSCs) provides a broad prospect for the treatment of periodontal disease. N-Acetyltransferase 10 (NAT10)-catalyzed non-histone acetylation is widely involved in physiological or pathophysiological processes. However, its function in hPDLSCs is still missing. hPDLSCs were isolated, purified, and cultured from extracted teeth. Surface markers were detected by flow cytometry. Osteogenic, adipogenic, and chondrogenic differentiation potential was detected by alizarin red staining (ARS), oil red O staining, and Alcian blue staining. Alkaline phosphatase (ALP) activity was assessed by ALP assay. Quantitative real-time PCR (qRT-PCR) and western blot were used to detect the expression of key molecules, such as NAT10, Vascular endothelial growth factor A (VEGFA), PI3K/AKT pathway, as well as bone markers (RUNX2, OCN, OPN). RNA-Binding Protein Immunoprecipitation PCR (RIP-PCR) was used to detect the N4-acetylcytidine (ac4C) mRNA level. Genes related to VEGFA were identified by bioinformatics analysis. NAT10 was highly expressed in the osteogenic differentiation process with enhanced ALP activity and osteogenic capability, and elevated expression of osteogenesis-related markers. The ac4C level and expression of VEGFA were obviously regulated by NAT10 and overexpression of VEGFA also had similar effects to NAT10. The phosphorylation level of PI3K and AKT was also elevated by overexpression of VEGFA. VEGFA could reverse the effects of NAT10 in hPDLSCs. NAT10 enhances the osteogenic development of hPDLSCs via regulation of the VEGFA-mediated PI3K/AKT signaling pathway by ac4C alteration.


Subject(s)
Periodontal Ligament , Proto-Oncogene Proteins c-akt , Humans , Proto-Oncogene Proteins c-akt/pharmacology , Osteogenesis/genetics , Vascular Endothelial Growth Factor A , Phosphatidylinositol 3-Kinases , Signal Transduction , Cell Differentiation , Stem Cells , Cells, Cultured , Cell Proliferation , N-Terminal Acetyltransferases
15.
Foods ; 12(2)2023 Jan 08.
Article in English | MEDLINE | ID: mdl-36673394

ABSTRACT

Cucumber fruit is very sensitive to chilling injury, which rapidly depreciates their commodity value. Herein, the effect of fucoidan treatment on cucumber under cold stress were investigated. Fucoidan treatment of cold-stored cucumber alleviated the occurrence of chilling injury, delayed weight loss, lowered electrolyte leakage and respiration rate, and retarded malondialdehyde accumulation. Different from the control fruit, fucoidan treated fruit showed a high level of fatty acid unsaturated content, fatty acid unsaturation, and unsaturation index and increased ω-FDAS activity, along with upregulated expression levels of CsSAD and CsFAD genes. Fucoidan reduced the phosphatidic acid content and membrane lipid peroxidation, lowered the phospholipase D (PLD) and lipoxygenase (LOX) activity, and downregulated the expression levels of CsPLD and CsLOX genes. Collectively, fucoidan treatment maintained the integrity of cell membrane in cold-stress cucumbers. The results provide a new prospect for the development of fucoidan as a preservative agent in the low-temperature postharvest storage of cucumbers.

16.
Article in English | MEDLINE | ID: mdl-36512203

ABSTRACT

A total of 300 day-old Arbor Acres Plus broiler chicks (mixed sex) was used to evaluate the effects of dietary supplementation of Bacillus subtilis, Clostridium butyricum, and Enterococcus faecalis mixture (PB) on growth performance, ileal morphology, and cecal microbiota. All birds were randomly assigned into 3 groups based on the initial body weight. There were 5 replicate cages per group and 20 birds per cage. The experimental period was 42 days. Dietary treatments were based on a basal diet and supplemented with 0, 0.05, or 0.10% PB. The results indicated that broiler chicks fed with the diet supplemented with graded levels of PB have quadratically improved their body weight gain and feed intake; the highest value was presented in 0.05% PB-containing group. In addition, villus to crypt ratio linearly increased with the concentration of PB increased in the diet. The alpha diversity linearly increased by PB supplementation, and the highest value was presented in 0.10% PB-containing group. In terms of growth performance, the suitable dose of PB used in the diet was 0.05%. However, ternary plot showed that the harmful bacteria, Escherichia-Shigella, was enriched in 0.05% PB-containing group. In brief, we considered that dietary supplementation of graded levels of PB improved growth performance and regulated cecal microbiota in broiler chicks.

17.
Org Lett ; 24(32): 6054-6059, 2022 Aug 19.
Article in English | MEDLINE | ID: mdl-35948075

ABSTRACT

A novel strategy of copper-catalyzed regio- and enantioselective hydrosilylation of 4-substituted vinylidenecyclohexanes with silanes was developed. In this protocol, various allenes and silanes were used to afford the corresponding (cyclohexylidene)ethyl silanes in moderate to high yields with good enantioselectivities.

18.
Org Lett ; 24(22): 4081-4086, 2022 06 10.
Article in English | MEDLINE | ID: mdl-35648807

ABSTRACT

A copper-catalyzed regioselective Markovnikov 3,4-hydrosilylation of 2-substituted 1,3-dienes has been accomplished. A wide range of 2-substituted 1,3-dienes and trihydrosilanes are compatible under the optimal conditions. The bisphosphine ligand with a rigid backbone provides the Markovnikov 3,4-hydrosilylation product in better yield and selectivity. Besides, the synthetic utilities of the allylsilanes also were demonstrated by their flexible derivatizations.


Subject(s)
Copper , Polyenes , Catalysis
19.
Org Lett ; 24(15): 2832-2836, 2022 Apr 22.
Article in English | MEDLINE | ID: mdl-35394282

ABSTRACT

A copper-catalyzed 1,4-protosilylation of α-alkynyl-enones to form the functionalized chiral homoallenylsilanes was developed. In the presence of a chiral monopyridine oxazoline ligand, a variety of trisubstituted allene derivatives bearing a contiguous stereogenic center and axis were prepared in good yields with excellent enantioselectivities and diastereoselectivities.

20.
Org Lett ; 24(14): 2660-2664, 2022 04 15.
Article in English | MEDLINE | ID: mdl-35377669

ABSTRACT

A copper-catalyzed borylation of propargyl dichlorides was developed under mild reaction conditions. The corresponding chloro-substituted allenyl-Bdan products were obtained in good yields. The utilities of allenyl-Bdan products were examined by their diverse derivatizations.


Subject(s)
Copper , Catalysis , Stereoisomerism
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