Simultaneous purification of minor components in natural products using twin-column recycling chromatography with a step solvent gradient

The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar compounds.This study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive constituents.By introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream column.Hence,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation process.Herein,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for separation.By using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC).

Research progress on natural products against hepatocellular carcinoma

Hepatocellular carcinoma(HCC)remains a prevalent and challenging malignancy globally,characterized by its numerous causal factors and generally unfavorable prognosis.In the relentless pursuit of effective treatment modalities,natural products have emerged as a promising and relatively non-toxic alternative,garnering significant interest.The integration of natural products with contemporary medical research has yielded encouraging therapeutic outcomes in the management of HCC.This review offers a comprehensive overview of the causal factors underlying HCC,and the diverse treatment options available,and highlights the advancements made by natural products in anti-HCC research.Particularly,we provide an outline of the various types of natural products,their corresponding nomenclature,target molecules,and mechanisms of action that exhibit anti-HCC activities.Natural products are anticipated to play a pivotal role in future comprehensive treatment plans for liver cancer,potentially offering patients improved survival rates and an enhanced quality of life.

Targeting oxidative stress with natural products: A novel strategy for esophageal cancer therapy

Esophageal cancer(ESC)is a malignant tumor that originates from the mucosal epithelium of the esophagus and is part of the digestive tract.Although the exact pathogenesis of ESC has not been fully elucidated,excessive oxidative stress is an important characteristic that leads to the development of many cancers.Abnormal expression of several proteins and transcription factors contributes to oxidative stress in ESCs,which alters the growth and proliferation of ESCs and promotes their metastasis.Natural compounds,including alkaloids,terpenes,polyphenols,and xanthine compounds,can inhibit reactive oxygen species production in ESCs.These compounds reduce oxidative stress levels and subsequently inhibit the oc-currence and progression of ESC through the regulation of targets and pathways such as the cytokine interleukins 6 and 10,superoxide dismutase,the NF-+ACY-kappa+ADs-B/MAPK pathway,and the mammalian Nrf2/ARE target pathway.Thus,targeting tumor oxidative stress has become a key focus in anti-ESC therapy.This review discusses the potential of Natural products(NPs)for treating ESCs and summarizes the application prospects of oxidative stress as a new target for ESC treatment.The findings of this review provide a reference for drug development targeting ESCs.Nonetheless,further high-quality studies will be necessary to determine the clinical efficacy of these various NPs.

Numerical Investigation of Combined Production of Natural Gas Hydrate and Conventional Gas

Natural gas hydrate(NGH)is generally produced and accumulated together with the underlying conventional gas.Therefore,optimizing the production technology of these two gases should be seen as a relevant way to effectively reduce the exploitation cost of the gas hydrate.In this study,three types of models accounting for the coexistence of these gases are considered.Type A considers the upper hydrate-bearing layer(HBL)adjacent to the lower conventional gas layer(CGL);with the Type B a permeable interlayer exists between the upper HBL and the lower CGL;with the type C there is an impermeable interlayer between the upper HBL and the lower CGL.The production performances associated with the above three models are calculated under different conditions,including only a depressurized HBL(only HBL DP);only a depressurized CGL(only CGL DP);and both the HBL and the CGL being depressurized(HBL+CGL DP).The results show that for Type A and Type B coexistence accumulation models,when only HBL or CGL is depressurized,the gas from the other layer will flow into the production layer due to the pressure difference between the two layers.In the coexistence accumulation model of type C,the cumulative gas production is much lower than that of Type A and Type B,regardless of whether only HBL DP,only CGL DP,or HBL+CGL DP are considered.This indicates that the impermeable interlayer restricts the cross-flow of gas between HBL and CGL.For three different coexistence accumulation models,CGL DP has the largest gas-to-water ratio.

Natural product-induced oxidative stress-synergistic anti-tumor effects of chemotherapeutic agents

Reactive oxygen species are closely related to tumor development.In recent years,reactive oxygen species has become a hot spot in tumor therapy,and many natural substances in nature contain compound components with anti-tumor effects.However,there is a lack of discussion on the synergistic anti-tumor effects of natural products in combination with chemotherapeutic drugs through reactive oxygen species.The terms“natural products”,“reactive oxygen species”,“anti-tumor”,and“chemotherapy”were used to identify the synergistic effects of natural products.We conducted a systematic literature search in PubMed and Web of Science databases for relevant research articles and reviews published in recent years.We systematically summarized the studies related to anti-tumor active ingredients in natural compounds in the field of reactive oxygen species in recent years.A total of 77 relevant literatures were included.Among them,45 literatures containing various natural products such as terpenoids,flavonoids,alkaloids,etc.exert anti-tumor effects by regulating reactive oxygen species levels,and 32 literatures regarding adjunctive role of natural products in anti-tumor therapy.In this study,we found that natural products exert anti-tumor effects by elevating reactive oxygen species levels.It provides strong theoretical support for future clinical studies.

Natural product-based treatment potential for type 2 diabetes mellitus and cardiovascular disease

BACKGROUND Type 2 diabetes(T2D)is a metabolic disease of impaired glucose utilization and a major cause of cardiovascular disease(CVD).The pathogenesis of both diseases shares common risk factors and mechanisms,and both are significant contributors to global morbidity and mortality.Supplements of natural products for T2D mellitus(T2DM)and CVD can be seen as a potential preventive and effective therapeutic strategy.AIM To critically evaluate the therapeutic potential of natural products in T2D and coronary artery disease(CAD).METHODS By using specific keywords,we strategically searched the PubMed database.Randomized controlled trials(RCTs)were searched as the primary focus that examined the effect of natural products on glycemic control,oxidative stress,and antioxidant levels.We focused on outcomes such as low blood glucose levels,adjustment on markers of oxidative stress and antioxidants.After screening fulllength papers,we included 9 RCTs in our review that met our inclusion criteria.RESULTS In the literature search on the database,we found that various natural products like plant secondary metabolites play a diverse role in the management of CAD.American ginseng,sesame oil and cocoa flavanols proved effective in lowering blood glucose levels and controlling blood pressure,which are key factors in managing T2DM and CVD.In diabetic patients Melissa officinalis effectively reduce inflammation and shows diabetes prevention.Both fish oil and flaxseed oil reduced insulin levels and inflammatory markers,suggesting benefits for both conditions.The lipid profile and endothelial function were enhanced by Nigella sativa oil and Terminalia chebula,which is significant for the management of cardiovascular risk factors in T2DM.Additionally Bilberry extract also showed promise for improving glycemic control in patients with T2DM.CONCLUSION The high level of antioxidant,anti-inflammatory,and anti-angiogenic properties found in natural products makes them promising therapeutic options for the management of CAD,with the potential benefit of lowering the risk of CAD.

Role of natural products and intestinal flora on type 2 diabetes mellitus treatment

Diabetes mellitus(DM)is a complicated,globally expanding disease that is influenced by hereditary and environmental variables.Changes in modern society’s food choices,physical inactivity,and obesity are significant factors in the development of type 2 DM(T2DM).The association between changes in intestinal flora and numerous disorders,including obesity,diabetes,and cardiovascular diseases,has been studied in recent years.The purpose of this review is to analyze the mechanisms underlying the alteration of the diabetic patients’intestinal flora,as well as their therapeutic choices.Also included is a summary of the antidiabetic benefits of natural compounds demonstrated by studies.The short-chain fatty acids theory,the bile acid theory,and the endotoxin theory are all potential methods by which intestinal flora contributes to the establishment and progression of T2DM.Due to an intestinal flora imbalance,abnormalities in shortchain fatty acids and secondary bile acids have been found in diabetic patients.Additionally,metabolic endotoxemia with altering flora induces a systemic inflammatory response by stimulating the immune system via bacterial translocation.The agenda for diabetes treatment includes the use of short-chain fatty acids,probiotics,prebiotics in the diet,fecal bacteria transplantation,and antibiotics.Animal studies have proven the antidiabetic benefits of numerous bioactive substances,including Flavonoids,Alkaloids,Saponin,and Allicin.However,further research is required to contribute to the treatment of diabetes.

Current therapeutic modalities and chemopreventive role of natural products in liver cancer:Progress and promise

Liver cancer is a severe concern for public health officials since the clinical cases are increasing each year,with an estimated 5-year survival rate of 30%–35%after diagnosis.Hepatocellular carcinoma(HCC)constitutes a significant subtype of liver cancer(approximate75%)and is considered primary liver cancer.Treatment for liver cancer mainly depends on the stage of its progression,where surgery including,hepatectomy and liver transplantation,and ablation and radiotherapy are the prime choice.For advanced liver cancer,various drugs and immunotherapy are used as first-line treatment,whereas second-line treatment includes chemotherapeutic drugs from natural and synthetic origins.Sorafenib and lenvatinib are first-line therapies,while regorafenib and ramucirumab are secondline therapy.Various metabolic and signaling pathways such as Notch,JAK/STAT,Hippo,TGF-β,and Wnt have played a critical role during HCC progression.Dysbiosis has also been implicated in liver cancer.Drug-induced toxicity is a key obstacle in the treatment of liver cancer,necessitating the development of effective and safe medications,with natural compounds such as resveratrol,curcumin,diallyl sulfide,and others emerging as promising anticancer agents.This review highlights the current status of liver cancer research,signaling pathways,therapeutic targets,current treatment strategies and the chemopreventive role of various natural products in managing liver cancer.

Mechanisms of action of natural products on type 2 diabetes

Over the past several decades,type 2 diabetes mellitus(T2DM)has been considered a global public health concern.Currently,various therapeutic modalities are available for T2DM management,including dietary modifications,moderate exercise,and use of hypoglycemic agents and lipid-lowering medications.Although the curative effect of most drugs on T2DM is significant,they also exert some adverse side effects.Biologically active substances found in natural medicines are important for T2DM treatment.Several recent studies have reported that active ingredients derived from traditional medicines or foods exert a therapeutic effect on T2DM.This review compiled important articles regarding the therapeutic effects of natural products and their active ingredients on isletβcell function,adipose tissue inflammation,and insulin resistance.Additionally,this review provided an in-depth understanding of the multiple regulatory effects on different targets and signaling pathways of natural medicines in the treatment of T2DM as well as a theoretical basis for clinical effective application.

Natural products and extracts from plants as natural UV filters for sunscreens:A review

Although solar exposure is necessary for human health,phototoxicology induced by excessive UVB and UVA radiation,which involves sunburns,skin aging and even tu-morigenesis,has been widely researched.Sunscreen is one of the most important ways to protect skin from UV phototoxic damage.As well as inorganic and organic UV filters,some natural products or plant extracts with aromatic rings in their structures,such as flavonoids or polyphenols,can absorb UV to reduce sunburn,acting as a natu-ral UV filter;they also show antioxidant or/and anti-inflammatory activity.This could explain why,although there are no officially approval natural commercial sun-filters,more and more commercial sunscreen products containing plant extracts are avail-able on the market.Here we summarize articles focusing on natural UV filters from plant published in the last 6 years,selecting the most significant data in order to better understand the photoprotective activity of natural products and extracts from plants,including their major constituents and main biological effects,methods for evaluating UV radiation resistance,anti-UV radiation experimental models and anti-UV radiation mechanisms.

Acute kidney injury:microRNAs and new therapeutic opportunities for natural products

In the past few decades,acute kidney injury(AKI),characterized by an abrupt decrease in kidney filtration rate,has become a public health issue affecting between 1%and 15%of the population,which causes high morbidity and death.There is mounting evidence that miRNAs are noncoding single-stranded RNAs with a short length of about 20 nucleotides and have been highly conserved through evolution.Through targeting mRNAs,miRNA may mediate intercellular communication during AKI’s physiological and pathological processes.It is interesting to note that natural products can improve AKI by regulating miRNA expression,which might represent a potentially innovative therapeutic strategy.This review aims at providing an overview of the new data obtained on miRNAs in the treatment and diagnosis of AKI,summarizing studies on natural products improving AKI through regulating miRNAs’expression;in the same time,it will shed new light on AKI risk biomarkers and therapeutic intervention as well.We summarized the roles of miRNAs involved in AKI progression or protection against renal injury in 32 articles;we found five natural products can improve AKI by regulating miRNA expression,which will potentially provide a reference for clinical treatment.Natural products might represent a potentially innovative therapeutic strategy;in the same time,miRNAs will shed new light on AKI risk biomarkers and therapeutic intervention.

Research progress of natural products in treating polycystic ovary syndrome

Polycystic ovary syndrome(PCOS)is a common metabolic disorder reproductive endocrine disease in puberty and women of childbearing age.At present,metformin is mainly used in clinical to treat PCOS.From recent researches,many natural products,such as flavonoids,alkaloids,cumarins,etc,showed curing effects on PCOS.These have been attracting more and more attention.By searching the researches from database of CNKI,PubMed etc,this paper aims at providing a reference for PCOS drug research and development.

Recent advance in natural plant products for treatment of dry eye disease

Dry eye disease(DED),a chronic multifactorial illness of the ocular surface with itching,burning,irritation,eye fatigue and ocular inflammation,may result in potential damage,such as cornea and conjunctiva,and even decreased vision.With the global prevalence of DED on the rise,it is crucial to find treatment options with minimal side effects.Natural plant products have shown promise in alleviating DED symptoms and may serve as a potential approach for its treatment.However,their application as instilled drugs is limited by solubility,stability and biological barriers.This review summarizes recent studies(published in the last 5 years)on natural plant products and their derivatives for the treatment of DED,focusing on efficacy,mechanism,drug delivery systems.Meanwhile,their shortcomings are also discussed.By exploring these aspects,we find polyphenol,flavonoid and others natural plant products can effectively improve or treat DED by different mechanisms,and suitable delivery system and structural modification can enhance their therapeutic effect,suggesting they are likely to become candidates for the treatment of DED.

A Review of Textile Fabrication Using Bioactive Compounds Derived from Natural Products

Antimicrobial-treated textiles should exhibit efficacy against a broad spectrum of bacterial and fungal species,all while maintaining user safety with a non-toxic profile.Natural antimicrobial compounds play a vital role in textile finishing processes.The proliferation of synthetic antimicrobial agents introduces environmental and consumer safety concerns.Given these potential hazards associated with synthetic agents,the utilization of natural antimicrobial agents is gaining traction,as they tend to have fewer adverse effects on users and are more environmentally sustainable.Numerous natural antimicrobial compounds,sourced from plants such as neem,basil,turmeric,aloe vera,and clove oil,have been developed,showcasing inherent antimicrobial properties.This review article highlights the importance of incorporating bioactive components in the creation of antibacterial textile fabrics.

Genetic and epigenetic targets of natural dietary compounds as anti-Alzheimer's agents

Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinesterase activity,mitochondrial dysfunction,genotoxicity,and neuroinflammation are present in this syndrome,which leads to neurodegeneration.Neurodegenerative pathologies such as Alzheimer’s disease are considered late-onset diseases caused by the complex combination of genetic,epigenetic,and environmental factors.There are two main types of Alzheimer’s disease,known as familial Alzheimer’s disease(onset<65 years)and late-onset or sporadic Alzheimer’s disease(onset≥65 years).Patients with familial Alzheimer’s disease inherit the disease due to rare mutations on the amyloid precursor protein(APP),presenilin 1 and 2(PSEN1 and PSEN2)genes in an autosomaldominantly fashion with closely 100%penetrance.In contrast,a different picture seems to emerge for sporadic Alzheimer’s disease,which exhibits numerous non-Mendelian anomalies suggesting an epigenetic component in its etiology.Importantly,the fundamental pathophysiological mechanisms driving Alzheimer’s disease are interfaced with epigenetic dysregulation.However,the dynamic nature of epigenetics seems to open up new avenues and hope in regenerative neurogenesis to improve brain repair in Alzheimer’s disease or following injury or stroke in humans.In recent years,there has been an increase in interest in using natural products for the treatment of neurodegenerative illnesses such as Alzheimer’s disease.Through epigenetic mechanisms,such as DNA methylation,non-coding RNAs,histone modification,and chromatin conformation regulation,natural compounds appear to exert neuroprotective effects.While we do not purport to cover every in this work,we do attempt to illustrate how various phytochemical compounds regulate the epigenetic effects of a few Alzheimer’s disease-related genes.

Sustainable, thermoplastic and hydrophobic coating from natural cellulose and cinnamon to fabricate eco-friendly catering packaging

Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which significantly affect the overall degradation performance of products.It is imperative and attractive to develop biodegradable functional coatings.Herein,we proposed a novel strategy to successfully prepare biodegradable,thermoplastic and hydrophobic coatings with high transparence and biosafety by weakening the interchain interactions between cellulose chain.The natural cellulose and cinnamic acid were as raw materials.Via reducing the degree of polymerization(DP)of cellulose and regulating the degree of substitution(DS)of cinnamate moiety,the obtained cellulose cinnamate(CC)exhibited not only the thermalflow behavior but also good biodegradability,which solves the conflict between the thermoplasticity and biodegradability in cellulose-based materials.The glass transition temperature(T_(g))and thermalflow temperature(T_(f))of the CC could be adjusted in a range of 150–200℃ and 180–210℃,respectively.The CC with DS<1.2 and DP≤100 degraded more than 60%after an enzyme treatment for 7 days,and degraded more than 80%after a composting treatment for 42 days.Furthermore,CC had no toxicity to human epidermal cells even at a high concentration(0.5 mg mL^(-1)).In addition,CC could be easily fabricated into multifunctional coating with high hydrophobicity,thermal adhesion and high transparence.Therefore,after combining with cellophane and paperboard,CC coating with low DP and DS could be used to prepare fully-biodegradable heat-sealing packaging,art paper,paper cups,paper straws and food packaging boxes.

Spatiotemporal variations of ecosystem services and driving factors in the Tianchi Bogda Peak Natural Reserve of Xinjiang,China

Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,is an important ecological barrier area in the temperate arid zone.The evaluation of its important ecosystem services is of great significance to improve the management level and ecological protection efficiency of the reserve.In the present study,we assessed the spatiotemporal variations of four ecosystem services(including net primary productivity(NPP),water yield,soil conservation,and habitat quality)in the TBPNR from 2000 to 2020 based on the environmental and social data using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.In addition,the coldspot and hotspot areas of ecosystem services were identified by hotspot analysis,and the trade-off and synergistic relationships between ecosystem services were analyzed using factor analysis in a geographic detector.During the study period,NPP and soil conservation values in the reserve increased by 48.20%and 25.56%,respectively;conversely,water yield decreased by 16.56%,and there was no significant change in habitat quality.Spatially,both NPP and habitat quality values were higher in the northern part and lower in the southern part,whereas water yield showed an opposite trend.Correlation analysis revealed that NPP showed a synergistic relationship with habitat quality and soil conservation,and exhibited a trade-off relationship with water yield.Water yield and habitat quality also had a trade-off relationship.NPP and habitat quality were affected by annual average temperature and Normalized Difference Vegetation Index(NDVI),respectively,while water yield and soil conservation were more affected by digital elevation model(DEM).Therefore,attention should be paid to the spatial distribution and dynamics of trade-off and synergistic relationships between ecosystem services in future ecological management.The findings of the present study provide a reference that could facilitate the sustainable utilization of ecosystem services in the typical fragile areas of Northwest China.

Experimental study on solid particle migration and production behaviors during marine natural gas hydrate dissociation by depressurization

Sand production is one of the main obstacles restricting gas extraction efficiency and safety from marine natural gas hydrate(NGH)reservoirs.Particle migration within the NGH reservoir dominates sand production behaviors,while their relationships were rarely reported,severely constrains quantitative evaluation of sand production risks.This paper reports the optical observations of solid particle migration and production from micrometer to mesoscopic scales conditioned to gravel packing during depressurization-induced NGH dissociation for the first time.Theoretical evolutionary modes of sand migration are established based on experimental observations,and its implications on field NGH are comprehensively discussed.Five particle migration regimes of local borehole failure,continuous collapse,wormhole expansion,extensive slow deformation,and pore-wall fluidization are proved to occur during depressurization.The types of particle migration regimes and their transmission modes during depressurization are predominantly determined by initial hydrate saturation.In contrast,the depressurization mainly dominates the transmission rate of the particle migration regimes.Furthermore,both the cumulative mass and the medium grain size of the produced sand decrease linearly with increasing initial methane hydrate(MH)saturation.Discontinuous gas bubble emission,expansion,and explosion during MH dissociation delay sand migration into the wellbore.At the same time,continuous water flow is a requirement for sand production during hydrate dissociation by depressurization.The experiments enlighten us that a constitutive model that can illustrate visible particle migration regimes and their transmission modes is urgently needed to bridge numerical simulation and field applications.Optimizing wellbore layout positions or special reservoir treatment shall be important for mitigating sand production tendency during NGH exploitation.

Efficient production optimization for naturally fractured reservoir using EDFM

Naturally fractured reservoirs make important contributions to global oil and gas reserves and production.The modeling and simulation of naturally fractured reservoirs are different from conventional reservoirs as the existence of natural fractures.To address the development optimization problem of naturally fractured reservoirs,we propose an optimization workflow by coupling the optimization methods with the embedded discrete fracture model(EDFM).Firstly,the effective and superior performance of the workflow is verified based on the conceptual model.The stochastic simplex approximate gradient(StoSAG)algorithm,the ensemble optimization(EnOpt)algorithm,and the particle swarm optimization(PSO)algorithm are implemented for the production optimization of naturally fractured reservoirs based on the improved versions of the Egg model and the PUNQ-S3 model.The results of the two cases demonstrate the effectiveness of this optimization workflow by finding the optimal well controls which yield the maximum net present value(NPV).Compared to the initial well control guess,the final NPV obtained from the production optimization of fractured reservoirs based on all three optimization algorithms is significantly enhanced.Compared with the optimization results of the PSO algorithm,StoSAG and EnOpt have significant advantages in terms of final NPV and computational efficiency.The results also show that fractures have a significant impact on reservoir production.The economic efficiency of fractured reservoir development can be significantly improved by the optimization workflow.

Treatment on Nature’s lap:Use of herbal products in the management of hyperglycemia

Diabetes mellitus(DM)is characterized by persistently elevated blood glucose concentration that lead to multisystem complications.There are about 400 medicinal plants cited to have a beneficial effect on DM.We must choose products wisely based on data derived from scientific studies.However,a major obstacle in the amalgamation of herbal medicine in modern medical practices is the lack of clinical data on its safety,efficacy and drug interaction.Trials of these herbal products often underreport the side effects and other crucial intervention steps deviating from the standards set by Consolidated Standards of Reporting Trials.Due to a lack of knowledge of the active compounds present in most herbal medicines,product standardization is difficult.Cost-effectiveness is another issue that needs to be kept in mind.In this mini-review,we focus on the antihyperglycemic effect of herbal products that are commonly used,along with the concerns stated above.