Low Molecular Weight Compounds Research Articles

Reverse microdialysis: A window into root exudation hotspots

Plant roots release a variety of low-molecular weight compounds, such as sugars, amino acids or organic acids into the soil, impacting microbial activities and physico-chemical soil processes in their surroundings. These compounds are a source of easily available Carbon (C) and energy for soil microbes, potentially accelerating microbial decomposition of soil organic matter in the immediate vicinity of roots. However, knowledge about processes in root exudation hotspots remains limited due to experimental difficulties in investigating such hotspots in soil.Microdialysis, a passive sampling technique based on diffusion, has been successfully used to collect soil solutes at small spatial scales. Reverse microdialysis, also termed retrodialysis, can be used to introduce solutes into the soil, mimicking passive root exudation. However, little is known about the dynamics of substances released by passive diffusion into intact soil, a crucial prerequisite for applying reverse microdialysis to study root exudation hotspots in undisturbed soils.Here, we used reverse microdialysis to investigate the spatial and temporal dynamics of thirteen different organic compounds passively introduced into two different intact soils. Diffusion of compounds into soils was substantially lower than into water, and was not – as in water – determined by molecular size. Interestingly, butyrate, oxalate and propionate showed the highest diffusive fluxes into soil combined with the lowest rate of back retrieval after input, indicating that they were quickly removed from the soil solution by biotic or abiotic processes. In contrast, glucose and fructose unexpectedly accumulated around the membrane after input without removal. Furthermore, diffusive fluxes of compounds into soils showed a fluctuating temporal pattern, which may be explained by an observed 2-h delay of microbial respiration of added 13C-labelled compounds. During the course of 12 days, approximately one third of 13C-labelled compounds introduced into soil was respired while 8% ended up in microbial biomass.Our results demonstrate that introducing compounds into intact soil triggers complex biotic and abiotic responses at the time scale of hours. Reverse microdialysis proved to be an excellent tool to investigate such responses as well as the dynamics and metabolic consequences of passively released compounds into intact soil, and – in combination with 13C labelled substrate and respiration measurements - to shed light on potential priming effects that may be triggered by them.

Targeting Mutant p53 for Cancer Treatment: Moving Closer to Clinical Use?

Simple SummaryCancer is largely caused by genetic alterations such as mutations in a group of genes known as cancer driver genes. Many of the key advances in cancer treatment in recent years have involved blocking these driver genes using a new generation of anti-cancer drugs. Although p53 is the most frequently mutated gene in human cancers, historically, it has proved difficult to develop drugs against it. However, recently, several new drugs have become available for neutralizing the cancer-promoting effects of mutant p53. The aim of this article is to discuss the most promising of these drugs, especially those that are being investigated in clinical trials.Mutant p53 is one of the most attractive targets for new anti-cancer drugs. Although traditionally regarded as difficult to drug, several new strategies have recently become available for targeting the mutant protein. One of the most promising of these involves the use of low molecular weight compounds that promote refolding and reactivation of mutant p53 to its wild-type form. Several such reactivating drugs are currently undergoing evaluation in clinical trials, including eprenetapopt (APR-246), COTI-2, arsenic trioxide and PC14586. Of these, the most clinically advanced for targeting mutant p53 is eprenetapopt which has completed phase I, II and III clinical trials, the latter in patients with mutant TP53 myelodysplastic syndrome. Although no data on clinical efficacy are currently available for eprenetapopt, preliminary results suggest that the drug is relatively well tolerated. Other strategies for targeting mutant p53 that have progressed to clinical trials involve the use of drugs promoting degradation of the mutant protein and exploiting the mutant protein for the development of anti-cancer vaccines. With all of these ongoing trials, we should soon know if targeting mutant p53 can be used for cancer treatment. If any of these trials show clinical efficacy, it may be a transformative development for the treatment of patients with cancer since mutant p53 is so prevalent in this disease.

Wear-Resistant Hydrophobic Coatings from Low Molecular Weight Polytetrafluoroethylene Formed on a Polyester Fabric

The paper presents a comparative analysis of the surface structure and morphology of hydrophobic coatings formed on a polyester fabric from various types of low molecular weight tetrafluoroethylenes by a new method. The low molecular weight compounds used include: ultrafine polytetrafluoroethylene of the FORUM® trademark prepared through thermo-gas-dynamic decomposition of industrial polytetrafluoroethylene waste, and tetrafluoroethylene telomers, synthesized by radiation-chemical initiation from fluoromonomers in acetone, butyl chloride and trimethylchlorosilane solutions. The formation of coatings consists in deposition of low molecular weight tetrafluoroethylenes from solutions in supercritical carbon dioxide and organic solvents. The contact angle and water absorption of the polyester fabric with coatings containing the specified water-repellents are determined. The resistance of the achieved effect to various types of wear—washing, dry cleaning and abrasionis evaluated. The hydrophobic properties of the fabric are found to be affected by the coating plasticity characterized by the stiffness coefficient. The importance of this indicator to targeted changes in fabric properties is proved. All the considered types of low molecular weight polytetrafluoroethylene (PTFE) are shown to be effective water-repellents for the polyester fabric.

The advanced treatment of textile printing and dyeing wastewater by hydrodynamic cavitation and ozone: Degradation, mechanism, and transformation of dissolved organic matter

The emission standards for textile printing and dyeing wastewater are stricter due to serious environmental issues. A novel technology, hydrodynamic cavitation combined with ozone (HC + O3), has attracted wide attention in wastewater advanced treatment, whereas the contaminants removal mechanism and transformation of dissolved organic matter (DOM) were rarely reported. This study investigated the removal efficiency and mechanism of HC + O3. The maximum removal rates of UV254, chrominance, CODCr, and TOC were 64.99%, 91.90%, 32.30%, and 36.67% in 60 min, respectively, at the inlet pressure of 0.15 MPa and O3 dosage of 6.25 mmol/L. The synergetic coefficient of HC + O3 was 2.77. The removal of contaminants was the synergy of 1O2, ·OH and ·O2−, and high molecular weight and strong aromaticity organic matters were degraded effectively. The main components in DOM were tryptophan-like and tyrosine-like, which were effectively removed after HC + O3. Meanwhile, most DOM had decreased to low apparent relative molecular weight (LARMW) compounds. Additionally, the HC + O3 effluent can reach the emission standard in 60 min for 8.07 USD/m3. It can be concluded that HC + O3 is an effective technology for the advanced treatment of industrial wastewater. This study will provide suggestions for the engineering application of HC + O3.

Photochemical transformation of sulfadiazine in UV/Fe(II)/sodium citrate Fenton-like system

The persistence and potential hazards of antibiotics in the aquatic environment have attracted worldwide attention. Currently, advanced oxidation technology is considered to be an effective way to degrade antibiotics in the water environment. An enhanced photochemical Fenton-like system was investigated in this study for degradation of antibiotic sulfadiazine (SDZ). The degradation kinetics, pathways, and mechanisms of SDZ in four different photocatalytic systems were studied, including ultraviolet (UV), UV/sodium citrate (SC), UV/Fe(II), and UV/Fe(II)/SC. The highest degradation rate of SDZ was observed in UV/Fe(II)/SC system, and the complexation of SC-Fe(II) promoted photocatalytic efficiency and iron cycling. It was proved that hydroxyl radicals (•OH) were generated in UV/Fe(II)/SC system, but excessive Fe(II) consumed •OH and produced a UV shielding effect, thus reducing the degradation rate of SDZ. In the UV/Fe(II)/SC system, the degradation of SDZ followed pseudo-first-order kinetics, and the reaction rate constant of SDZ reached a maximum of 8.49 × 10−3 min−1, with a degradation efficiency of 97.7%. Even in different real water samples, the removal rate of SDZ can reach about 80%. HCO3−, SO42−, and NO3− in the water environment inhibited the degradation of SDZ, and the order of inhibition was as follows: SO42− > HCO3−>NO3−. With the increase of SDZ concentration and high concentration of humic acid (HA), the degradation rate of the target compound decreased. By identifying the photodegradation products of SDZ, four degradation pathways were proposed, and it revealed that the N–C bond and N–S bond were broken by attacking of hydroxyl groups, where a hydroxyl group replaced the H atom, resulting in the decomposition of SDZ into low molecular weight compounds like SO2, CO2, NO3− and H2O. It suggested that the UV/Fe(II)/SC system has good effect and application prospect in SAs treatment.

The catalytic hydrothermal liquefaction of lignin to produce aromatics over nickel metal hydrotalcite catalysts

In this study, a series of Ni(5,10,15 and 20) wt%/MgAl2O4 catalysts were prepared and used for the catalytic depolymerization of lignin under three varying solvents namely, methanol, ethanol and water, couple with varying reaction environment (N2, and H2). Highest bio-oil yield (81.8 wt%) was found with 15 wt%Ni/MgAl2O4 catalyst in ethanol solvent under hydrogen environment at 280 °C for 30 min reaction time. Under this condition higher heating value 36.2 MJ/kg of bio-oil was obtained, which is significantly increases from 24.5 MJ/kg of lignin. Under nitrogen environments bio-oil analysis showed that, it was consisted of mainly of alkyl phenols (Ca. 68%) and methoxy phenols (24.0%) compounds. Intriguingly, a deoxygenating and hydrogenation reaction was promoted by hydrogen, which further produced 38.2% of higher cyclohexane compounds and 19% of aromatic hydrocarbon. GPC analysis showed that hydrogen enhanced the lower molecular weight compounds. Catalysts stability test showed excellent recyclability.

GAMBARAN HASIL PEMERIKSAAN HEPATITIS C PADA PASIEN GAGAL GINJAL KRONIK (GGK) YANG MENJALANI HEMODIALISA DI RUMAH SAKIT UNIVERSITAS SUMATERA UTARA

Chronic Kidney Disease (CKD) is a pathophysiological process with diverse etiologies, resulting in a progressive decrease in kidney function, and generally ending in renal failure. CKD is a clinical condition characterized by an irreversible decrease in kidney function that requires kidney replacement therapy in the form of dialysis or kidney transplantation. According to data from the Indonesian Nephrology Association in 2015, it is estimated that there are 90 thousand people with Chronic Kidney Disease in Indonesia, but those detected to suffer from terminal stage chronic kidneys from those undergoing dialysis (hemodialysis) are only up to five thousand to six thousand. Dialysis is a process of separating macromolecules from ions and low molecular weight compounds in solution by utilizing differences in their diffusion rates through semi-permeable membranes. One of the main techniques used in dialysis is hemodialysis. The basic principle of hemodialysis technique is the diffusion of solutes and water from plasma to dialysis solutions in response to certain differences in concentration and pressure. This technique has a risk of infection because it uses direct access to blood vessels. One of the infections that can occur in hemodialysis is infection from the hepatitis C virus. Immunochromatographic examination method ASSAY (ICA) or called the strip test (Strip Test), which is only by dripping a sample and diluents / buffer into a strip test and in certain incubation the results can already be seen with the eyes without the help of certain tools. (Standart Diagnostics, INC). Based on the sex of patients who are male infected with hepatitis C virus as many as 4 people (20%), while those who are female as many as 3 people (15%), based on the length of time to do hemodialysis, patients who are positive for Hepatitis C virus < 1 year the duration of hemodialysis is 2 people (10%), and those infected with Hepatitis C virus > 1 year as many as 5 people (25%).

Survey on Adsorption of Low Molecular Weight Compounds in Cu-BTC Metal-Organic Framework: Experimental Results and Thermodynamic Modeling.

This contribution aims at providing a critical overview of experimental results for the sorption of low molecular weight compounds in the Cu-BTC Metal–Organic Framework (MOF) and of their interpretation using available and new, specifically developed, theoretical approaches. First, a literature review of experimental results for the sorption of gases and vapors is presented, with particular focus on the results obtained from vibrational spectroscopy techniques. Then, an overview of theoretical models available in the literature is presented starting from semiempirical theoretical approaches suitable to interpret the adsorption thermodynamics of gases and vapors in Cu-BTC. A more detailed description is provided of a recently proposed Lattice Fluid approach, the Rigid Adsorbent Lattice Fluid (RALF) model. In addition, to deal with the cases where specific self- and cross-interactions (e.g., H-bonding, Lewis acid/Lewis base interactions) play a role, a modification of the RALF model, i.e., the RALFHB model, is introduced here for the first time. An extension of both RALF and RALFHB is also presented to cope with the cases in which the heterogeneity of the rigid adsorbent displaying a different kind of adsorbent cages is of relevance, as it occurs for the adsorption of some low molecular weight substances in Cu-BTC MOF.

Rice husk integrated biochemical refinery for the production of nano- and bioproducts

Rice husk contains high contents of cellulose, lignin, and inorganic compounds, which can be recovered and utilized in a variety of useful applications. In this study, rice husk was refined using a multistage process for producing nano- and bioproducts. To begin, the material was treated with dilute sulfuric acid for obtaining a pentose solution, which was then used for Candida utilis yeast fermentation. In the next stage, the pre-hydrolyzed rice husk was treated with an alkaline solution under regular pulping conditions to break down all chemical bonds between the substances in the material. Subsequently, cellulose was extracted for nanocellulose production, while lignin and silica were isolated via acid precipitation. Proper conditions for these processes were established. Under suitable conditions, about 55.0% of the rice husk was effectively utilized. Over 75.0% of the rice husk pentosan was converted into xylose and arabinose for single-cell protein fermentation. Lignin was mostly transformed into lower molecular weight compounds or single substances, resulting in a recovery rate of about 17.0%. The precipitation’s pH for silica and lignin recovery was 8.5 and 3.0, respectively. The findings of this work provide an effective solution for the utilization of agricultural residue and contribute significantly to the sustainable development.

Phenotypic screening of low molecular weight compounds is rich ground for repurposed, on-target drugs.

A target-based drug discovery strategy has led to a bias away from low molecular weight (MWT) drug discovery. Analysis of the ACS chemistry registration system shows that most low MWT drugs were first made in the time era before target-based drug discovery. Therapeutic activity among most low MWT drugs was identified in the era of phenotypic drug discovery when drugs were selected based on their phenotypic effects and before in vitro screening, mechanism of action considerations and experiences with fragment screening became known. The common perception that drugs cannot be found among low MWT compounds is incorrect based on both drug discovery history and our own experience with MLR-1023. The greater proportion of low MWT compounds that are commercially available compared to higher MWT compounds is a factor that should facilitate biology study. We posit that low MWT compounds are more suited to identification of new therapeutic activity using phenotypic screens provided that the phenotypic screening method has enough screening capacity. On-target and off-target therapeutic activities are discussed from both a chemistry and biology perspective because of a concern that either phenotypic or low MWT drug discovery might bias towards promiscuous compounds that combine on-target and off-target effects. Among ideal drug repositioning candidates (late-stage pre-clinical or clinically-experience compounds), pleiotropic activity (multiple therapeutic actions) is far more likely due to on-target effects arising where a single target mediates multiple therapeutic benefits, a desirable outcome for drug development purposes compared to the off-target alternative. Our exemplar of a low MWT compound, MLR-1023, discovered by phenotypic screening and subsequently found to have a single mechanism of action would have been overlooked based on current era medicinal chemistry precedent. The diverse therapeutic activities described for this compound by us, and others arise from the same pleiotropic lyn kinase activation molecular target. MLR-1023 serves as a proof-of-principle that potent, on target, low MWT drugs can be discovered by phenotypic screening.

Organic carbon compounds associated with deep soil carbon stores

AimsOrganic carbon has been reported in deep regolithic profiles to depths of tens of metres, but the composition of the carbon compounds is unknown.MethodsResidual carbon in the form of non-volatile low molecular weight compounds (LMWC) was characterised in three deep soil profiles to a depth of 19 m under farmland in south-western Australia following extraction with ethyl acetate and analysis by GC/MS. Pyrolysis and off-line thermochemolysis were used to characterise macromolecular organic carbon (MOC) to a depth of 29 m at a fourth site.ResultsThree compound classes occurred across the three different field locations: (1) terpenes, (2) fatty acids, amides and alcohols, and (3) plant steroids; indicating the influence of input of the past and present vegetation. Compounds related to fatty acids were the predominant residual carbon species in deep soils, and may be derived from plants and microorganisms. Biomarkers such as lignin, polysaccharides, proteins and terpenes at 0–0.1 m implied influences of vegetation, fire events and microorganisms. Pyrolysis found that polysaccharides were distributed mainly from 0 to 0.1 m, while aromatic compounds were consistently detected down to 29 m.Conclusions Carbon was stabilised in the form of aromatic compounds in deep soil, whereas other carbon sources such as cellulose, chitin, and N-containing compounds were confined to the surface soil. LMWC (Z)-docos-13-enamide and bis(6-methylheptyl) phthalate, were the main components throughout the soil profiles representing 53–81% of the LMWC, and were a greater proportion of the organic matter at depths of 18–19 m.

Metabolite profiling reveals insights into the species-dependent cold stress response of the green seaweed holobiont Ulva (Chlorophyta)

The green seaweed Ulva (Chlorophyta) and its associated epibacterial microbiome form a functional holobiont that adapts to stress as a whole. As the macroalga provides carbon sources for bacteria and relies on algal growth and morphogenesis-promoting factors (AGMPF) released by bacteria, those cross-kingdom interactions are especially fascinating. We hypothesized that the Ulva holobionts from the warm-temperate Mediterranean-Atlantic and cold Antarctic habitats respond to cold stress differently depending on the production of highly polar low molecular weight compounds (LMWCs) with stress-regulating activity. We compared the microbiome of and metabolic changes in U. compressa (cultivar U. mutabilis ), initially collected in Ria Formosa (Portugal), with that of U. bulbosa (strain AWI #1002) collected in Antarctica by performing a warm-cold temperature shift experiment. Microbiome analysis indicated significant differences between the two species and that the number of operational taxonomic units (OTUs) was lower in cultivated U. bulbosa than in freshly isolated Ulva ; despite this, AGMPF-producing bacteria were detected in both holobionts. Significant differences in metabolite profiles were observed between both species using hydrophilic interaction liquid chromatography coupled with electrospray ionization mass spectrometry (HILIC-ESI-MS). Biomarkers such as dimethylsulfoniopropionate (DMSP) and taurine were identified following a temperature shift from 18 °C to 5 °C in the warm-temperate U. mutabilis and the cold-adapted U. bulbosa , respectively. Our findings show that metabolic changes in the holobiont in response to cold are species-dependent. To evaluate the contribution of the metabolic changes of bacteria and algae to the stress response, the reductionistic model system of the tripartite community formed by U. mutabilis and its two essential bacteria, Roseovarius sp. strain MS2 and Maribacter sp. strain MS6, which release all essential AGMPFs, was investigated. We examined the production of polar LMWCs in the presence and absence of bacteria following a shift to cold temperatures. Among the metabolites studied, ectoine ((4 S )-2-methyl-3,4,5,6-tetrahydropyrimidine-4-carboxylic acid) was only detected in the presence of bacteria, highlighting the role of bacteria in releasing compounds that mitigate environmental stresses through cold stress adaptation factors (CSAF). Our findings suggest that microbiome engineering will allow us to improve macroalgae adaptability to stressful situations, which can be further applied to the sustainable management of (land-based) aquaculture systems. • Algal growth and morphogenesis promoting bacteria were found in cultures of Ulva independently of their origin and habitat. • Low molecular weight compounds (LMWC) of the holobiont were examined upon cold stress. • Cold stress triggers diverse potential cryoprotectants in warm- and cold-adapted Ulva. • Taurine and DMSP may be considered as species-specific stress biomarkers. • Axenic Ulva cultures elucidate the bacterial contribution to the production of LMWC.

A Liquid Chromatography-Mass Spectrometry Method to Study the Interaction between Membrane Proteins and Low-Molecular-Weight Compound Mixtures.

Molecular interaction analysis is an essential technique for the study of biomolecular functions and the development of new drugs. Most current methods generally require manipulation to immobilize or label molecules, and require advance identification of at least one of the two molecules in the reaction. In this study, we succeeded in detecting the interaction of low-molecular-weight (LMW) compounds with a membrane protein mixture derived from cultured cells expressing target membrane proteins by using the size exclusion chromatography-mass spectrometry (SEC-MS) method under the condition of 0.001% lauryl maltose neopentyl glycol as detergent and atmospheric pressure chemical ionization. This method allowed us to analyze the interaction of a mixture of medicinal herbal ingredients with a mixture of membrane proteins to identify the two interacting ingredients. As it does not require specialized equipment (e.g., a two-dimensional liquid chromatography system), this SEC-MS method enables the analysis of interactions between LMW compounds and relatively high-expressed membrane proteins without immobilization or derivatization of the molecules.

Evaluation of the Accessibility of Molecules in Hydrogels Using a Scale of Spin Probes.

In this work, we explored by means of electron paramagnetic resonance (EPR) spectroscopy the accessibility of a series of spin probes, covering a scale of molecular weights in the range of 200–60,000 Da, in a variety of hydrogels: covalent network, ionotropic, interpenetrating polymer network (IPN) and semi-IPN. The covalent gel network consists of polyethylene or polypropylene chains linked via isocyanate groups with cyclodextrin, and the ionotropic gel is generated by alginate in the presence of Ca2+ ions, whereas semi-IPN and IPN gel networks are generated in a solution of alginate and chitosan by adding crosslinking agents, Ca2+ for alginate and glutaraldehyde for chitosan. It was observed that the size of the diffusing species determines the ability of the gel to uptake them. Low molecular weight compounds can diffuse into the gel, but when the size of the probes increases, the gel cannot uptake them. Spin-labelled Pluronic F127 cannot be encapsulated by any covalent gel, whereas spin-labelled albumin can diffuse in alginate gels and in most of the IPN networks. The EPR spectra also evidenced the specific interactions of spin probes inside hydrogels. The results suggest that EPR spectroscopy can be an alternate method to evaluate the mesh size of gel systems and to provide information on local interactions inside gels.

A rational structure-based drug design strategy for the discovery of novel antiviral agents against the Yellow Fever Virus helicase

Yellow Fever is a viral hemorrhagic disease that is transmitted mainly through arthropods with high mortality rates. Yellow Fever Virus (YFV) is an enveloped positive sense single-stranded RNA virus, member of the Flaviviridae family and the Flavivirus genus, and is endemic in countries of Africa and South America. However, recent cases of infection in North America, Asia and Europe are highlighting the potential risk of an outbreak with no effective treatment available and the urgent need to develop potent antiviral agents against the YFV. In this direction a range of specific modulators were designed and in silico evaluated in an effort to hinder the enzymatic activity of the YFV helicase as a prominent pharmacological target. Following a structure-based rational drug design pipeline, a phylogenetic analysis of Flaviviridae viruses and an in-depth evolutionary study on the Yellow Fever Virus helicase has provided invaluable insights into structural conservation and structural elements and features that are vital for the viral helicase function. Using comparative modelling and molecular dynamics simulations the YFV helicase-ssRNA complex was established, and the specific molecular interactions and physicochemical properties of the complex could be analyzed and used towards the designing and elucidation of a specific YFV 3D pharmacophore model. A high throughput virtual screening simulation was conducted to assess a set of in-house maintained low molecular weight compounds as bioactive inhibitors of the YFV helicase enzyme. The in-silico study described herein, could pave the way towards the designing and more efficient screening of potential novel modulator compounds against the YFV as well as attest and designate the NS3 helicase as an antiviral pharmacological target of uttermost value and potential.

Silver Nanostructured Substrates in LDI-MS of Low Molecular Weight Compounds.

Mass spectrometric techniques can provide data on the composition of a studied sample, utilizing both targeted and untargeted approaches to solve various research problems. Analysis of compounds in the low mass range has practical implications in many areas of research and industry. Laser desorption ionization techniques are utilized for the analysis of molecules in a low mass region using low sample volume, providing high sensitivity with low chemical background. The fabrication of substrates based on nanostructures to assist ionization with well-controlled morphology may improve LDI-MS efficiency for silver nanoparticles with plasmonic properties. In this work, we report an approach for the preparation of silver nanostructured substrates applied as laser desorption ionization (LDI) plates, using the chemical vapor deposition (CVD) technique. Depending on the mass of used CVD precursor, the approach allowed the synthesis of LDI plates with tunable sensitivity for various low molecular weight compounds in both ion-positive and ion-negative modes. Reduced chemical background and sensitivity to small biomolecules of various classes (fatty acids, amino acids and water-soluble metabolites) at nanomolar and picomolar detection levels for lipids such as triacylglycerols, phosphatidylethanolamines and lyso-phosphatidylcholines represent an emerging perspective for applications of LDI-MS plates for the collection of molecular profiles and targeted analysis of low molecular weight compounds for various purposes.

Time Depletion Effects on the Volatile Compounds from the Distillation Extracts of Prunella vulgaris and the Dynamics of their Extraction.

Prunella vulgaris (PV) is a low-growing perennial herb, which can be found in different parts of the world as Asia, Europe and North America. It is traditionally used for medicinal treatment in various cultures in India, China, Japan, Korea, Russia, and Eastern Europe for treating different ailments, such as fever, and healing wounds. In our previous article, we showed the anti-tumorous effect of the volatile organic compounds (VOCs) of PV and characterized the steam distillation process in the extraction of VOCs from PV. This has never been done before as we are aware of. To use the VOCs as drugs, there is a question of how much of the VOCs are lost before the prepared drugs reach the patients. Thus, the first aim of the present article is to try to explore the time depletion effect on the VOCs in the PV extracts. Then, the second aim is to extend the work in the previous paper and further understand the dynamics of the distillation process of PV by changing the steam flow rate in the extraction process. To achieve the first aim to explore the aging effect of how much VOCs are depleted after they are extracted, the VOCs were first extracted by the same method as before, i.e., using steam distillation. Then, tubes of the aqueous solution containing the VOCs were then stored in a 5°C refrigerator. They were then taken out for GC-MS analysis according to a preplanned schedule up to 8 weeks after the VOCs were extracted. The chemical composition of the distillate could then be evaluated. This revealed the changes in the abundance of VOCs with aging. At the same time, the cell viability of SCC154 oral squamous cells treated by these herbal solutions, which were at different aging stages, was evaluated using a tetrazolium-based colorimetric reagent, Cell Counting Kit-8. To achieve the second aim of exploring the dynamics of the steam distillation process, the steam flow rate was adjusted by changing the temperature setting of the hot plate. GC-MS was again used to quantify the chemical constituents of the distillates. By using GC-MS to measure the abundance of volatile compounds at different time points after the distillation process, it was found that the volatile compounds persist for a very long time, or over 8 weeks, which was the longest period of our experiment. The aging of the distillates also did not depreciate much the cell cytotoxicity of the PV distillate on the cancer cells. With respect to the dynamics of the steam distillation process, it was found that, at a low steam flow rate, volatile compounds of lower molecular weight are more efficient to be extracted, while at a high steam flow rate, volatile compounds of higher molecular weight are more efficiently extracted. Our findings demonstrate that the VOC compounds extracted and present in aqueous form do not deplete much for at least 2 months after the extraction process, neither they exhibit cell cytotoxicity. The experiments on the dynamics of the steam distillation process demonstrate that the mass of herb present in the flow path of the steam has significant effects on the relative amounts of VOCs extracted.

CHEMICAL MIGRATION FROM CONTAINERS MANUFACTURED WITH POLYPROPYLENE TOWARDS FATTY FOODS

Processed foods present migration of chemical compounds after the packaging process, and the main migrants come from plastic containers, in which multiple additives are added to improve the functional properties of polymers and incorporate them into transformation processes and subsequent use in packing plants. Additionally, the use of new materials has increased and with it the number of hazards that are incorporated into its chemical structure, which is why this study aims to identify possible chemical compounds that migrate from containers made of plastic materials based on polypropylene resin (PP) that are used to be in direct contact with fatty foods. Due to the above, a bibliographic review type investigation was carried out, identifying the list of chemical compounds with potential risk to the health of the consumer, being low molecular weight compounds one of the most important problems, however, this type of raw materials continues to gain ground in the market, from the results obtained from various investigations show that 83% migration of chemical compounds comes from mixing between (Irganox 1076, Irganox 1010 and irgafos168). In this way, this research constitutes a source of important bibliographic information to carry out a specialized study on the migration of compounds into food and a starting point to implement monitoring or regulations on migrating compounds in PP containers in Ecuador.

Low Fluorinated Oligoamides for Use as Wood Protective Coating

New highly hydrophobic fluorinated oligoamides were synthesized and studied as materials for the protection of non-varnishable wooden artifacts. The new oligoamides were designed to achieve the best performance (including high chemical affinity to the wood material) and the lowest environmental impact. In order to minimize the risk of bioaccumulation, short perfluoroalkyl side chains were reacted with oligoethylene L-tartaramide (ET), oligoethylene adipamide-L-tartaramide (ETA), oligoethylene succinamide-L-tartaramide (EST), oligoethylene succinamide (ES), and oligodiethylenetriamino-L-tartaramide (DT). Favorable reaction conditions were also adopted to obtain low molecular weight compounds characterized by non-film-forming properties and solubility or dispersibility in environmentally friendly organic solvents. Their behavior in terms of modification of the wood surface characteristics, such as wettability, moisture absorption, and color, was analyzed using a specific diagnostic protocol to rapidly obtain preliminary, but reliable, results for optimizing a future synthesis of new and tailored protectives. The influence of different monomer units on the reactivity, solubility, and hydrophobic properties of different oligoamides was compared showing ESF (contact angle 138.2°) and DF (132.2°) as the most effective products. The study of stability to photochemical degradation confirms ESF as promising protective agents for artefacts of historical and artistic interest in place of long-chain perfluoroalkyl substances (PFAS), products currently subject to restrictions on use.

Role of osmoprotectants: transgenic approach for different stresses

Plants have an in-built mechanism to cope with various environmental stress conditions. One such approach is activation of genes which governs the stress conditions. Out of the many stress related genes, some genes code for osmolytes or osmoprotectants. These belong to a group of low molecular weight compounds which are non-toxic compounds and help in stabilizing cellular structures and enzymes during the stress situation. Since the family is quite big, so for a fair understanding, these are grouped into different categories. For a better understanding of osmoprotectant related gene expression and their regulation in response to biotic and abiotic stress, this review cites the recent research works related to osmoprotectants and the genetic approach undertaken with these genes in other plant species.