Mechanism Of Products Research Articles

Gut microecology: effective targets for natural products to modulate uric acid metabolism.

Gut microecology,the complex community consisting of microorganisms and their microenvironments in the gastrointestinal tract, plays a vital role in maintaining overall health and regulating various physiological and pathological processes. Recent studies have highlighted the significant impact of gut microecology on the regulation of uric acid metabolism. Natural products, including monomers, extracts, and traditional Chinese medicine formulations derived from natural sources such as plants, animals, and microorganisms, have also been investigated for their potential role in modulating uric acid metabolism. According to research, The stability of gut microecology is a crucial link for natural products to maintain healthy uric acid metabolism and reduce hyperuricemia-related diseases. Herein, we review the recent advanced evidence revealing the bidirectional regulation between gut microecology and uric acid metabolism. And separately summarize the key evidence of natural extracts and herbal formulations in regulating both aspects. In addition,we elucidated the important mechanisms of natural products in regulating uric acid metabolism and secondary diseases through gut microecology, especially by modulating the composition of gut microbiota, gut mucosal barrier, inflammatory response, purine catalyzation, and associated transporters. This review may offer a novel insight into uric acid and its associated disorders management and highlight a perspective for exploring its potential therapeutic drugs from natural products.

Thermal degradation of capsaicin and dihydrocapsaicin: Mechanism and hazards of volatile products

Food safety issues have become unprecedentedly notable. To ensure the safe use of capsaicin (CAP) and dihydrocapsaicin (DHCAP) in the food sector, their thermal degradation characteristics was examined for the first time through thermogravimetric analysis (TGA) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) analysis. The second major phase occurred within the temperature range of 265–425 ℃, leading to substantial weight reductions of 96.13 % for CAP and 92.76 % for DHCAP. Thermodynamic parameters, calculated using the Flynn–Wall–Ozawa (FWO), Kissinger–Akahira–Sunose (KAS), and Coats–Redfern (C–R) methods, indicated that the thermal decomposition of both CAP and DHCAP was non-spontaneous and followed an F1 mechanism (−ln(1−α)). The pyrolysis of CAP and DHCAP released several volatile compounds, including CAP, DHCAP, Z-9-octadecenamide, octadecanamide, 9-decenenitrile, nonanenitrile, and 8-methylnonanoic acid. These compounds may pose certain toxicological risks and potential hazards to human health. The pyrolytic pathways for CAP and DHCAP are likely to involve the cleavage of alkyl C-N and/or amide bonds, as well as processes of deamidation and demethylation. Therefore, it is prudent to avoid heating food containing CAP and DHCAP above 265 ℃ during culinary preparation.

Recent Developments of Transition‐Metal‐Catalyzed Cross‐Coupling of Nitriles and Alcohols

AbstractCross‐coupling of nitriles and alcohols offers an environmentally friendly and atom‐economical method for the synthesis of various valuable compounds. These compounds include α‐alkylated and α‐olefinated nitriles, primary amines, imines, N‐alkylation amines, amides, N‐heterocycles, δ‐hydroxynitriles, olefins, etc. Herein, we have reviewed recent developments (from 2013–date) of transition‐metal‐catalyzed cross‐coupling of nitriles and alcohols. A number of transition metal complexes such as noble metals Ru and Ir, as well as base metals Mn, Fe, Co, and Ni are presented. Moreover, different product types, reaction conditions and mechanisms are discussed to understand the reaction and catalyst development.

Degradation of Isopyrazam in Soil: Kinetics, Microbial Mechanism, and Ecotoxicity of the Transformation Product.

The degradation of isopyrazam in soils was investigated through kinetics, microbial contributions, and transformation products (TPs). Then the acute toxicity of isopyrazam and its TP to Chlorella pyrenoidosa was explored. The half-lives of isopyrazam in cinnamon soil, red soil, and black soil were 82.2, 141.7, and 120.3 days, respectively. A strain (Bacillus sp. A01) isolated from cinnamon soil could degrade 72.9% of isopyrazam at 10 mg/L after 6 days in a Luria-Bertani medium. Six TPs were observed with Bacillus sp. A01, and three of them were found in soil as well. Through the inhibition of cytochrome P450 enzymes, the production of oxidized isopyrazam was blocked. Microbial mediated hydroxylation, epoxidation, and dehydration were the main degradation pathways of isopyrazam. The acute toxicity results showed that the EC50 of 3-(difluoromethyl)-N-(9-(2-hydroxypropan-2-yl)-1,2,3,4-tetrahydro-1,4-methanonaphthalen-6-yl)-1-methyl-1H-pyrazole-4-carboxamide to Chlorella pyrenoidosa was 40 times higher than that of the parent. This work provides new insights for understanding the degradation behavior of isopyrazam in soil.

Spatio-Temporal Changes and Driving Mechanisms of Vegetation Net Primary Productivity in Xinjiang, China from 2001 to 2022

Net primary productivity (NPP), a key indicator of terrestrial ecosystem quality and function, represents the amount of organic matter produced by vegetation per unit area and time. This study utilizes the MOD17A3 NPP dataset (2001–2022) to analyze the spatio-temporal dynamics of NPP in Xinjiang and projects future trends using Theil-Sen trend analysis, the Mann–-Kendall test, and the Hurst Index. By integrating meteorological data, this study employs partial correlation analysis, the Miami model, and residual analysis to explore the driving mechanisms behind NPP changes influenced by climatic factors and human activities. The results indicate that: (1) The average NPP in Xinjiang has increased over the years, displaying a spatial pattern with higher values in the north and west. Regions with increasing NPP outnumber those with declining trends, while 75.18% of the area shows un-certain future trends. (2) Precipitation exhibits a stronger positive correlation with NPP compared to temperature. (3) Climate change accounts for 28.34% of the variation in NPP, while human activities account for 71.66%, making the latter the dominant driving factor. This study aids in monitoring ecological degradation risks in arid regions of China and provides a scientific basis for developing rational coping strategies and ecological restoration initiatives.

Impacts of finned rotating cylinder on hydrothermal flow of hybrid nanofluids in a vented cavity based on dynamic mesh approach

This study aims to explore and enhance the understanding of how finned rotating cylinders impact mixed convection of the hydrothermal flow and heat transfer of hybrid nanofluids in a vented cavity. The significance of this study contributes to the advancement of increasingly efficient and productive thermal control mechanisms in diverse industrial sectors employing rotating cylinders. Simulations employ a dynamic mesh approach to model the flow domain and boundary motion of the rotating bladed cylinder based on the finite volume technique. The presented results underwent a rigorous comparison with existing related works in the open literature. The chosen working fluid is a Newtonian hybrid nanofluid composed of SiO2-Al2O3 suspended in water. Various configurations of cylinder locations and sizes are examined, alongside a broad spectrum of associated variables with certain ranges. These parameters with defined ranges are; Reynolds numbers (2 × 102 ≤ Re ≤ 1 × 103), cylinder radius (0.1 ≤ R≤0.3), cylinder locations (0.25 ≤ δ ≤ 0.75), spinning speeds (− 3 ≤ Ω ≤ 3), and nanoparticle concentrations (0 ≤ φ1 ≤ 0.03 and 0 ≤ φ2 ≤ 0.03). The results indicate significant impacts of Reynolds numbers (Re), Grashof numbers (Gr), cylinder radius (R), location (δ), spinning speed (Ω), and the number of blades on the hydrothermal characteristics. The major finding states that the cylinder radius of 0.3 for Case 5 with five fins provides the greatest enhancement of mixed flow and relatively maximum heat transfer rate. Furthermore, increasing concentrations of nanoparticles (φ) of hybrid nanofluids further improves the thermal performance.

Regulating phenol tar in pyrolysis of lignocellulosic biomass: Product characteristics and conversion mechanisms

The utilization of biomass pyrolysis is a crucial approach for sustainable development. This study used the typical biomass of pine (PI), rice husk (RH), and corn straw (ST) as feedstocks to evaluate the pyrolysis mechanisms, features and conversion mechanisms of the phenol tar product. The phenolic gaseous products were more trailing in ST, which mostly concentrated around 320–500 °C. Primary phenol tar is produced from lignin through the homolytic cleavage of β-O and α-O, and C-C bond breakage, primarily occurring before 550 °C. As the degree of aromatization increases, the oxygenates progressively deoxygenate, and the primary tar demethoxylates to form secondary tar as the temperature increases. The pyrolysis of cellulose produces H radicals, which aid the transformation of lignin into phenol tar. This study can provide a theoretical basis for biomass pyrolysis to select the appropriate process parameters to improve the quality of bio-oil and regulate phenol tar products.

Natural product pharmacology: the British Journal of Pharmacology perspective.

Natural products (NPs) have long been used as a rich source of bioactive compounds for drug development. Recent technological advancements have revitalised natural products research as evidenced by increased publications in this field. In this editorial review, we highlight key points from the 2020 British Journal of Pharmacology (BJP) practical guide, which outlines standards for natural products research reports, and provide papers published in BJP between years 2020 to 2023 that demonstrate adherence to these guidelines. Looking ahead, we discuss the potential of chemical proteomics approaches to elucidate natural products mechanisms of action and identify therapeutic targets for future research. By fostering innovation, we aim to advance natural products research and contribute to the development of novel therapeutics that will have a significant impact on healthcare.

Diversity-enhanced canopy space occupation and leaf functional diversity jointly promote overyielding in tropical tree communities

Understanding the mechanisms that drive biodiversity-productivity relationships is critical for guiding forest restoration. Although complementarity among trees in the canopy space has been suggested as a key mechanism for greater productivity in mixed-species tree communities, empirical evidence remains limited. Here, we used data from a tropical tree diversity experiment to disentangle the effects of tree species richness and community functional characteristics (community-weighted mean and functional diversity of leaf traits) on canopy space filling, and how these effects are related to overyielding. We found that canopy space filling was largely explained by species identity effects rather than tree diversity effects. Communities with a high abundance of species with a conservative resource-use strategy were those with most densely packed canopies. Across monocultures and mixtures, a higher canopy space filling translated into an enhanced wood productivity. Importantly, most communities (83 %) produced more wood volume than the average of their constituent species in monoculture (i.e. most communities overyielded). Our results show that overyielding increased with leaf functional diversity and positive net biodiversity effects on canopy space filling, which mainly arose due to a high taxonomic diversity. These findings suggest that both taxonomic diversity-enhanced canopy space filling and canopy leaf diversity are important drivers for overyielding in mixed-species forests. Consequently, restoration initiatives should promote stands with functionally diverse canopies by selecting tree species with large interspecific differences in leaf nutrition, as well as leaf and branch morphology to optimize carbon capture in young forest stands.

Skin Delivery and Innovative Carrier’s Effectiveness

The skin serves as the body first protecting barrier against the external attacks of chemicals and microorganisms. On the other hand, it is an obstacle to penetration and transdermal delivery of any substance applied on its surface. Thus, a need to report some news on the skin composition for a better understanding of the transdermal delivery mechanisms of topical products applied on its surface. Therefore, due to the actual increased use of topical drugs, cosmetics, and diet supplement treatments, further feasibility research studies have been carried out to extend the knowledge of the percutaneous absorption ‘rules and means. These studies are retained necessary to control the release through the skin layers of various selected active ingredients, loaded and carried out by different vehicles. The paper will focus on the effectiveness of innovative tissue carriers that, are able to deliver active ingredients throughout the skin layers, are made by a very low consumption of water, and are free of chemicals also. In conclusion, these novel eco-sustainable carriers, resulting skin- and environmentally friendly, might be used as innovative vehicles in substitution of the normal emulsions that, made by the use of preservatives, emulsifiers, fragrances, and other chemicals may often cause allergic and/or sensitization phenomena, consuming a great quantity of water also.

Natural Products in the Treatment of Retinopathy of Prematurity: Exploring Therapeutic Potentials.

Retinopathy of prematurity (ROP) is a vascular disorder affecting the retinas of preterm infants. This condition arises when preterm infants in incubators are exposed to high oxygen levels, leading to oxidative stress, inflammatory responses, and a downregulation of vascular endothelial growth factors, which causes the loss of retinal microvascular capillaries. Upon returning to room air, the upregulation of vascular growth factors results in abnormal vascular growth of retinal endothelial cells. Without appropriate intervention, ROP can progress to blindness. The prevalence of ROP has risen, making it a significant cause of childhood blindness. Current treatments, such as laser therapy and various pharmacologic approaches, are limited by their potential for severe adverse effects. Therefore, a deeper understanding of ROP's pathophysiology and the development of innovative treatments are imperative. Natural products from plants, fungi, bacteria, and marine organisms have shown promise in treating various diseases and have gained attention in ROP research due to their minimal side effects and wide-ranging beneficial properties. This review discusses the roles and mechanisms of natural products that hold potential as therapeutic agents in ROP management.

Mechanism, Formulation, and Efficacy Evaluation of Natural Products for Skin Pigmentation Treatment.

Skin pigmentation typically arises from the excessive secretion and accumulation of melanin, resulting in a darker complexion compared to normal skin. Currently, the local application of chemical drugs is a first-line strategy for pigmentation disorders, but the safety and efficacy of drugs still cannot meet clinical treatment needs. For long-term and safe medication, researchers have paid attention to natural products with higher biocompatibility. This article begins by examining the pathogenesis and treatment approaches of skin pigmentation diseases and summarizes the research progress and mechanism of natural products with lightening or whitening effects that are clinically common or experimentally proven. Moreover, we outline the novel formulations of natural products in treating pigmentation disorders, including liposomes, nanoparticles, microemulsions, microneedles, and tocosomes. Finally, the pharmacodynamic evaluation methods in the study of pigmentation disorder were first systematically analyzed. In brief, this review aims to collect natural products for skin pigmentation treatment and investigate their formulation design and efficacy evaluation to provide insights for the development of new products for this complex skin disease.

Antifungal Mechanism of Natural Products Derived from Plants: A Review

Fungal resistance to the limited existing antifungal agents has become a considerable public health problem in the past few decades. However, natural products with multiple bioactivities are important sources for developing new therapeutic agents against fungi. Consequently, there is an urgent need to grasp the antifungal mechanism of natural products. In this review, the primary antifungal mechanisms of natural products derived from plants, including targeting the cell wall, cell membrane, mitochondria, biofilm and other mechanisms, are elaborated. This article critically describes the compounds with high antifungal activity, revealing opportunities for future research such as clinical trials or utilization as environmental disinfectants.

I2/CAN as an efficient reagent for the direct oxidation of tertiary Csp3-H to Csp3-OH: Synthesis of bis(N-methyl-7-azaindol-3-yl) (phenyl) methanol from 3,3′-(phenyl methylene)-bis(N-methyl-7-azaindole)

I2/CAN has emerged as a powerful and efficient oxidizing agent for direct tertiary CH oxidation of 3,3′-(phenyl methylene) bis(N-methyl-7-azaindole) under mild conditions to form bis(N-methyl-7-azaindol-3-yl) (phenyl)methanol in quantitative yield. Further, based on control experiments, a plausible mechanism and characterization of products including XRD are described. Synthetic transformation for bis(N-methyl-7-azaindol-3-yl) (phenyl) methanol is achieved by thionation.

Interaction mechanism of products from sulfidation roasting of nickel oxide with flotation reagents

Interaction mechanism of products from sulfidation roasting of nickel oxide with flotation reagents

Content Promotion and Community Experience: Marketing Mechanisms and Paths for Outdoor Sports Products--The Case of Arc'teryx

In the post epidemic period, outdoor sports have become a new trend in sports, and the demand for outdoor sports products has also increased. Among the many outdoor sports brands, Arc'teryx stands out and becomes the new favourite of people who love outdoor sports. So how did Arc'teryx become a big hit in the highly competitive outdoor sports market, with sales rising year after year? Currently, there are few detailed analyses of the brand's marketing mechanism and path. Therefore, the theme of this paper is the marketing mechanism and path of outdoor sports products--Taking Arc'teryx as an example. The research method is mainly case study method, mainly focusing on content marketing, analysing how the brand attracts audiences and builds communities through content marketing. The study found that Arc'teryx content marketing helped its own positioning and accurately attracted target customers, and the community experience also strengthened the brand's connection with customers. However, there are also shortcomings: the brand has fewer offline shops nationwide than other outdoor brands, and not all of them have a unique environment like the first shop in Shanghai to attract customers to buy. Arc'teryx still needs to revise its marketing strategy when the outdoor trend goes out of fashion to ensure that sales continue to grow, attract more people to participate in outdoor activities, and also maintain the vitality of the community and its appeal to the outside world. However, there's no denying that other outdoor sports brands can learn from Arc'teryxs marketing.

The Influence of Groundwater Migration on Organic Matter Degradation and Biological Gas Production in the Central Depression of Qaidam Basin, China

For insight into the productive and storage mechanisms of biogas in the Qaidam Basin, efforts were made to investigate the groundwater recharge and the processes of hydrocarbon generation by CDOM-EEM (fluorescence excitation-emission matrix of Chromophoric dissolved organic matter) spectrum, hydrogen and oxygen isotopes, and geochemical characters in the central depression of the Qaidam Basin, China. The samples contain formation water from three gas fields (TN, SB, and YH) and surrounding surface water (fresh river and brine lake). The results indicate that modern precipitation significantly controls the salinity distribution and organic matter leaching in the groundwater system of the central depression of the Qaidam Basin. Higher salinity levels inhibit microbial activity, which leads to organic matter degradation and to gas generation efficiency being limited in the groundwater. The inhabitation effect is demonstrated by the notable negative correlation between the extent of organic matter degradation and its concentration with hydrogen and oxygen isotopes. The conclusion of this study indicated that modern precipitation emerges as a crucial factor affecting the biogas production and storage in the Qaidam Basin by influencing the ultimate salinity and organic matter concentration in the formation, which provides theoretical insight for the maintenance of modern gas production wells and the assessment of gas production potential.

Ex-situ catalytic fast pyrolysis of waste polycarbonate for aromatic hydrocarbons: Utilizing HZSM-5/modified HZSM-5

Catalytic pyrolysis has been proven as a highly efficient process for transforming waste polycarbonate (PC) into valuable aromatic hydrocarbons, especially benzene, toluene, ethylbenzene, and xylene (BTEX). In the present work, the ex-situ catalytic fast pyrolysis of PC on metal- or alkali-modified HZSM-5 was investigated using the double micro-fixed bed system. Experimental results indicate that the rapid pyrolysis of PC may follow a homolytic chain scission mechanism, resulting in pyrolysis products dominated by phenols. Metal- or alkali-modified HZSM-5 significantly enhances the cleavage of C-OH bonds in phenols, improving the yield of aromatics. The yield of aromatics in the liquid product is 91 %, 72 %, and 77 % when loaded with nickel (Ni), iron (Fe), and cobalt (Co), respectively, all of which are higher than unmodified HZSM-5 with the yield of 43 %. Among them, the Ni/HZSM-5 has significantly enhanced the yield of BTEX reaching 81.64 %. When using alkali-modified HZSM-5 with a larger pore volume and higher specific surface area, the yield of aromatics can be increased to 60 %. Furthermore, the dual modification of alkali treatment and Ni loading on HZSM-5 simultaneously enhanced catalytic activity and resistance to coke formation. The yield of BTEX reaches 94.47 %. The BTEX formation mechanism can be explained by direct deoxygenation (DDO) of the pyrolytic volatiles of PC and the “phenol pool” mechanisms of primary products on the catalyst surface. This study enriches the understanding of catalytic pyrolysis of PC and provides a theoretical foundation for the harmless treatment of PC.

Response mechanism of ecosystem gross primary productivity to cloud and aerosol changes in a Chinese winter-wheat cropland.

Changes in clouds and aerosols may alter the quantity of solar radiance and its diffuse components, as well as air temperature (Ta) and vapor pressure deficit (VPD), thereby affecting canopy photosynthesis. Our aim was to determine how ecosystem gross primary productivity (GPP) responds to the cloudiness and aerosol depth changes, as indicated by diffuse light fraction (fDIF). The environmental factors that caused these responses were examined using 2 years of eddy covariance data from a winter-wheat cropland in northern China. The GPP decreased significantly along with the fDIF in a nonlinear pattern, with a determination coefficient of 0.91. Changes in fDIF altered total photosynthetic active radiation (PAR), diffuse PAR, Ta and VPD. The variations in GPP with fDIF in both fDIF change Phase I (fDIF < 0.65) and Phase II (fDIF > 0.65) resulted from the combined effects of multiple environmental factors. Because the driving factors were closely correlated, a path analysis was used to distinguish their respective contribution to the GPP response to fDIF by integrating path coefficients. In Phases I and II, the decreased responses of GPP to fDIF were mainly caused by total PAR and diffuse PAR, respectively, which contributed approximately 49% and 37% to GPP variations, respectively. Our research has certain implications for the necessity to consider fDIF and to incorporate diffuse light into photosynthetic models.

Theoretical study of the reaction of organic peroxyl radicals with alkenes and their accretion products involved in the atmospheric nucleation

Organic peroxy radicals, including alkyl peroxy radicals (RO2) and acyl peroxy radicals (RC(O)O2), are crucial intermediates in the atmospheric photochemical reactions of volatile organic compounds and directly or indirectly affect the distribution of other species (e.g., HO2 radicals, NOx, OH radicals, and alkenes). However, the atmospheric reactions of organic peroxyl radicals with alkenes (RO2 + alkene reactions) are not fully understood. The present study used theoretical calculations to investigate the reaction mechanisms of various organic peroxy radicals with different alkenes, with the aim of clarifying the influence of molecular structure on RO2 + alkene and RC(O)O2 + alkene reactions. Furthermore, we investigated the nucleation mechanisms of the subsequent oxidation products. The results show that the reaction rate constants for RC(O)O2 + alkene reactions are 1–6 orders of magnitude higher than those for RO2 + alkene reactions. The addition products formed by organic peroxy radicals with alkenes not only undergo monomolecular reactions to generate epoxides, but also participate in O2 addition to yield the accretion products ROOR’. H2SO4 molecules synergistically interact with low-volatility ROOR’ to grow clusters up to the 1–2 nm scale, and the ROOR’ molecules can form pure organic clusters larger than 1 nm, even in the absence of H2SO4 molecules. Our study provides a new perspective on the formation of accretion products in the atmosphere and their involvement in new particle formation.