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Organic & Biomolecular Chemistry Dec 2023The plant hormone abscisic acid (ABA) plays a critical role in various environmental stress responses and has long been expected to be used in agriculture. However, the...
The plant hormone abscisic acid (ABA) plays a critical role in various environmental stress responses and has long been expected to be used in agriculture. However, the practical use of ABA has been limited, mainly because of its photoinstability and rapid biodegradation. We previously developed photostable ABA agonists, BP2A and Me 1',4'--diol BP2A, in which the dienoic acid side chain of ABA was replaced with phenylacetic acid. This finding validated our structure-based approach in designing photostable agonists and provided a basis for developing a more potent or long-lasting ABA agonist. In this study, we synthesized novel BP2A analogs in which the cyclohexenone ring was modified to avoid catabolism by the ABA metabolic enzyme, ABA 8'-hydroxylase. All synthesized analogs showed higher photostability than BP2A under sunlight. In an seed germination assay, (+)-compounds 5 and 6 with a tetralone ring displayed significantly stronger ABA agonist activity than (+)-BP2A. In contrast, in the phosphatase assays, both compounds showed comparable or weaker ABA receptor (PYL1) agonistic activity than (+)-BP2A, suggesting that the stronger ABA-like activity of (+)-5 and (+)-6 may arise from their metabolic stability This study provides data relevant to designing photostable and persistent ABA agonists.
Topics: Abscisic Acid; Plant Growth Regulators; Arabidopsis; Arabidopsis Proteins; Carrier Proteins
PubMed: 38018712
DOI: 10.1039/d3ob01518a -
Bulletin of Experimental Biology and... Aug 2023We studied the effect of amphotericin B (2.5×10 and 5.4×10 M) on osmotic resistance and surface cytoarchitectonics of donor blood erythrocytes. Antibiotic at a...
We studied the effect of amphotericin B (2.5×10 and 5.4×10 M) on osmotic resistance and surface cytoarchitectonics of donor blood erythrocytes. Antibiotic at a concentration of 2.5×10 M induced most pronounced changes in the studied parameters, which can be related to the specifics of the spatial organization of the cholesterol-amphotericin B complexes at different stoichiometric ratios of the components and their ability to pore formation in the membranes. Cholesterol binding to the polyene antibiotic and the appearance of perforations in the plasma membrane lead to accumulation of reversibly and irreversibly deformed cells and their hemolysis. The appearance of a large number of irreversibly deformed erythrocytes indicates an impaired ability to elastic deformation in the microcirculatory stream, which can lead to disruption of their functions in vivo and intravascular hemolysis.
Topics: Humans; Amphotericin B; Anti-Bacterial Agents; Microcirculation; Polyenes; Erythrocytes; Cholesterol; Hemolysis
PubMed: 37770787
DOI: 10.1007/s10517-023-05888-x -
ACS Applied Materials & Interfaces Feb 2024To inhibit viral infection, it is necessary for the surface of polypropylene (PP), a polymer of significant industrial relevance, to possess biocidal properties....
To inhibit viral infection, it is necessary for the surface of polypropylene (PP), a polymer of significant industrial relevance, to possess biocidal properties. However, due to its low surface energy, PP weakly interacts with other organic molecules. The biocidal effects of quaternary ammonium compounds (QACs) have inspired the development of nonwoven PP fibers with surface-bound quaternary ammonium (QA). Despite this advancement, there is limited knowledge regarding the durability of these coatings against scratching and abrasion. It is hypothesized that the durability could be improved if the thickness of the coating layer were controlled and increased. We herein functionalized PP with three-dimensionally surface-grafted poly(-benzyl-4-vinylpyridinium bromide) (PBVP) by a simple and rapid method involving graft polymerization and benzylation and examined the influence of different factors on the antiviral effect of the resulting plastic by using a plaque assay. The thickness of the PBVP coating, surface roughness, and amount of QACs, which jointly determine biocidal activity, could be controlled by adjusting the duration and intensity of the ultraviolet irradiation used for grafting. The best-performing sample reduced the viral infection titer of an enveloped model virus (bacteriophage ϕ6) by approximately 5 orders of magnitude after 60 min of contact and retained its antiviral activity after surface polishing-simulated scratching and abrasion, which indicated the localization of QACs across the coating interior. Our method may expand the scope of application to resin plates as well as fibers of PP. Given that the developed approach is not limited to PP and may be applied to other low-surface-energy olefinic polymers such as polyethylene and polybutene, our work paves the way for the fabrication of a wide range of biocidal surfaces for use in diverse environments, helping to prevent viral infection.
Topics: Humans; Polypropylenes; Quaternary Ammonium Compounds; Polymers; Virus Diseases; Antiviral Agents; Polyvinyls; Pyridinium Compounds; Vinyl Compounds
PubMed: 38343039
DOI: 10.1021/acsami.3c15125 -
Journal of Agricultural and Food... Sep 2023Zeaxanthin is a carotenoid, a dihydroxy derivative of β-carotene. Zeaxanthin has antioxidant, anti-inflammatory, anticancer, and neuroprotective properties. In this...
Zeaxanthin is a carotenoid, a dihydroxy derivative of β-carotene. Zeaxanthin has antioxidant, anti-inflammatory, anticancer, and neuroprotective properties. In this study, was used as a host for the efficient production of zeaxanthin. The strain PO1h was used to construct the following engineered strains for carotenoid production since it produced the highest β-carotene among the PO1h- and PEX17-HA-derived strains. By regulating the key nodes on the carotenoid pathway through wild and mutant enzyme comparison and successive modular assembly, the β-carotene concentration was improved from 19.9 to 422.0 mg/L. To provide more precursor mevalonate, heterologous genes and were introduced to increase the production of β-carotene by 27.2% to the yield of 536.8 mg/L. The β-carotene hydroxylase gene was then transferred, resulting in a yield of zeaxanthin of 326.5 mg/L. The oxidoreductase RFNR1 and CrtZ were then used to further enhance zeaxanthin production, and the yield of zeaxanthin was up to 775.3 mg/L in YPD shake flask.
Topics: Metabolic Engineering; beta Carotene; Yarrowia; Zeaxanthins; Carotenoids
PubMed: 37676277
DOI: 10.1021/acs.jafc.3c01772 -
Journal of Environmental Management Dec 2023Environmental concerns associated with the rapid rising plastic consumption have led to the search for better waste utilization and management. Pyrolysis has emerged as...
Environmental concerns associated with the rapid rising plastic consumption have led to the search for better waste utilization and management. Pyrolysis has emerged as an ideal and promising technique for energy extraction from plastic waste. The aim of this work is to explore the waste plastic pyrolysis behavior under non-isothermal heating conditions. The decomposition characteristics, reaction mechanism, kinetics and thermodynamics of a typical widely used thermosetting plastic, acrylonitrile butadiene styrene (ABS), were studied via coupled thermogravimetry, Fourier transform infrared spectrometry and gas chromatography-mass spectrometry analysis (TG-FTIR-GC/MS). Kinetic analysis showed the average E values are estimated to be 187.02, 188.55, 187.04 and 185.67 kJ/mol via advanced Vyazovkin, Flynn-Wall-Ozawa (FWO), Tang and Starink model-free method, respectively. Model-fitting CR and master-plots method indicated that f(α)=(1-α) is the most probable reaction mechanism. The equation of kinetic compensation effect was further developed as lnA = -3.1955 + 0.1736 E. Based on these initial inferences, a new reaction scheme coupled with Particle Swarm Optimization (PSO) was put forward for modeling ABS pyrolysis. The optimized values of E, A and n are 198.07 kJ/mol, 7.61 × 10 s and 1.56, respectively. The predicted results showed that the experimental data can be well characterized by the optimized parameters from PSO, validating the effectiveness and accuracy of the inverse modeling procedure. Moreover, it is found that the volatile products are mainly composed of aromatic compounds, ketones, amines, esters, nitrile compounds, alkenes and amines. Based on the FT-IR and GC-MS results, the possible chemical reactions for ABS pyrolysis from molecular structure were proposed. Finally, thermodynamic analysis was carried out, the calculated values of enthalpy ΔH, Gibb's free energy ΔG and entropy ΔS indicated that non-spontaneous reactions with low favorability exists during ABS decomposition, the process is complex therefore extra energy is needed to promote the reaction. The obtained results should offer as an important reference for future disposal and thermochemical management of such polymer waste.
Topics: Acrylonitrile; Kinetics; Spectroscopy, Fourier Transform Infrared; Butadienes; Styrene; Thermogravimetry; Amines
PubMed: 37827086
DOI: 10.1016/j.jenvman.2023.119080 -
Angewandte Chemie (International Ed. in... Sep 2023Many terpenoids with isoprene unit(s) demonstrating critical biological activities have been isolated and characterized. In this study, we have developed a robust...
Many terpenoids with isoprene unit(s) demonstrating critical biological activities have been isolated and characterized. In this study, we have developed a robust chem-stamp strategy for the construction of the key isoprene unit, which consists of two steps: one-carbon extension of aldehydes to the alkenyl boronates by the boron-Wittig reaction and the rhodium-catalyzed reaction of alkenyl boronates with 2,3-allenols to yield enals. This chem-stamp could readily be applied repeatedly and separately, enabling the modular concise synthesis of many natural and pharmaceutically active terpenoids, including retinal, β-carotene, vitamin A, tretinoin, fenretinide, acitretin, ALRT1550, nigerapyrone C, peretinoin, and lycopene. Owing to the diversified availability of the starting materials, aldehydes and 2,3-allenols, creation of new non-natural terpenoids has been realized from four dimensions: the number of isoprene units, the side chain, and the two terminal groups.
Topics: Terpenes; Hemiterpenes; Butadienes; Aldehydes; Catalysis
PubMed: 37439109
DOI: 10.1002/anie.202307626 -
European Journal of Pediatrics Jun 2024To describe the variability in carotenoid content of human milk (HM) in mothers of very to extremely low birth weight preterm infants throughout lactation and to explore...
To describe the variability in carotenoid content of human milk (HM) in mothers of very to extremely low birth weight preterm infants throughout lactation and to explore the relationship between lutein in HM and the occurrence of retinopathy of prematurity (ROP) in preterm infants. We recruited healthy mothers along with their preterm infants that were born at gestational age 24 + 2 to 29 + 6 weeks or with a birth weight under 1500 g and were exclusively breastfed HM. Each participant provided up to 7 HM samples (2-10 ml) on day 0-3 and once a week until 6 weeks. Additionally, when possible, a blood sample was collected from the infant at week 6. Concentrations of the major carotenoids (lutein, zeaxanthin, beta-carotene, and lycopene) in all HM and blood samples were assessed and compared. Thirty-nine mother-infant dyads were included and 184 HM samples and 21 plasma samples were provided. Mean lutein, zeaxanthin, beta-carotene, and lycopene concentration decreased as lactation progressed, being at their highest in colostrum samples (156.9 vs. 66.9 vs. 363.9 vs. 426.8 ng/ml, respectively). Lycopene (41%) and beta-carotene (36%) were the predominant carotenoids in colostrum and up to 2 weeks post-delivery. Inversely, the proportion of lutein and zeaxanthin increased with lactation duration to account for 45% of the carotenoids in mature HM. Lutein accounted for 58% of the carotenoids in infant plasma and only 28% in HM. Lutein content of transition and mature HM did not differ between mothers of ROP and non-ROP infants.Conclusion Carotenoid content of HM was dynamic and varied between mothers and as lactation progressed. Infant plasma displayed a distinct distribution of carotenoids from HM.
Topics: Humans; Milk, Human; Female; Carotenoids; Infant, Newborn; Adult; Longitudinal Studies; Retinopathy of Prematurity; Infant, Premature; Male; Lactation; Colostrum; Breast Feeding; Lutein
PubMed: 38509232
DOI: 10.1007/s00431-024-05485-8 -
Journal of Natural Products Aug 2023Turonicin A () was isolated from sp. MST-123921, which was recovered from soil collected on the banks of the Turon River in New South Wales, Australia. Turonicin A ()...
Turonicin A () was isolated from sp. MST-123921, which was recovered from soil collected on the banks of the Turon River in New South Wales, Australia. Turonicin A () is an amphoteric linear polyene polyketide featuring independent pentaene and tetraenone chromophores and is structurally related to linearmycins A-C (-). The structure of was determined by detailed spectroscopic analysis and comparison to literature data. Bioinformatic analysis of the linearmycin biosynthetic gene cluster also allowed the previously unresolved absolute stereostructures of - to be elucidated. Turonicin A () exhibited very potent activity against the fungi (MIC 0.0031 μg/mL, 2.7 nM) and (MIC 0.0008 μg/mL, 0.7 nM), moderate activity against the bacteria (MIC 0.097 μg/mL, 85 nM) and (MIC 0.39 μg/mL, 340 nM), and no cytotoxicity against human fibroblasts, making it an attractive candidate for further development as a potential next-generation antibiotic scaffold.
Topics: Humans; Antifungal Agents; Polyketides; Streptomyces; Australia; Anti-Bacterial Agents; Polyenes; Microbial Sensitivity Tests
PubMed: 37526586
DOI: 10.1021/acs.jnatprod.3c00144 -
Water Science and Technology : a... Dec 2023Microplastic (MP) pollution is a growing concern and various methods are being sought to alleviate the level of pollution worldwide. This study investigates the...
Microplastic (MP) pollution is a growing concern and various methods are being sought to alleviate the level of pollution worldwide. This study investigates the biodegradation capacity of MPs by indigenous microorganisms of raw water from Tehran drinking water treatment plants. By exposing polypropylene (PP) and polyethylene (PE) MPs to selected microbial colonies, structural, morphological, and chemical changes were detected by scanning electron microscope (SEM), cell weight measurement, Fourier transform infrared (FTIR), Raman spectroscopy test, and thermal gravimetric analysis (TGA). Selected bacterial strains include Pseudomonas protegens strain (A), Bacillus cereus strain (B), and Pseudomonas protegens strain (C). SEM analysis showed roughness and cracks on PP MPs exposed to strains A and C. However, PE MPs exposed to strain B faced limited degradation. In samples related to strain A, the Raman spectrum was completely changed, and a new chemical structure was created. Both TGA and FTIR analysis confirmed changes detected by Raman analysis of PP and PE MPs in chemical changes in this study. The results of cell dry weight loss for microbial strains A, B, and C were 13.5, 38.6, and 25.6%, respectively. Moreover, MPs weight loss was recorded at 32.6% for PP MPs with strain A, 13.3% for PE MPs with strain B, and 25.6% for PP MPs with strain C.
Topics: Biodegradation, Environmental; Environmental Monitoring; Iran; Microplastics; Plastics; Polyethylene; Polypropylenes; Water Pollutants, Chemical
PubMed: 38096084
DOI: 10.2166/wst.2023.360 -
Journal of Drugs in Dermatology : JDD Apr 2024Chronic exposure to ultraviolet light photoages skin. Retinol, a precursor molecule to retinoic acid that causes less irritation, is available as a nonprescription,...
INTRODUCTION
Chronic exposure to ultraviolet light photoages skin. Retinol, a precursor molecule to retinoic acid that causes less irritation, is available as a nonprescription, cosmetic retinoid and improves collagen production, skin elasticity, and signs of photoaging. Advances in formulation science have allowed the production of stabilized bioactive retinol formulations. This integrated analysis aims to build on previous studies and further examine the comprehensive efficacy and tolerability of topical 0.1% stabilized bioactive retinol.
METHODS
This analysis included 6 vehicle-controlled studies of 0.1% stabilized bioactive retinol in women with mild-to-moderate signs of photodamage. Across all studies, the same dermatologist investigator assessed overall photodamage; wrinkles on the forehead, cheeks, and undereye area; crow’s feet wrinkles and fine lines; lack of even skin tone; and brown spots at baseline and weeks 4, 8, and 12 on a numerical scale. Tolerability was also assessed.
RESULTS
Participants (retinol, N=237; vehicle, N=234) had a mean (SD) age of 47.4 (6.6) years. Retinol induced greater improvements from baseline in all signs of photoaging vs vehicle as early as week 4 and through 12 weeks of application. Few participants experienced irritation; all events were mild to moderate and transient. The most common signs of irritation were erythema (n=2) and skin scaling/peeling (n=5).
CONCLUSIONS
This pooled analysis of 6 vehicle-controlled clinical studies provides new evidence for the efficacy of 0.1% stabilized bioactive retinol in improving signs of photoaging without causing major irritation. Topical 0.1% stabilized bioactive retinol was well tolerated with only a few reported cases of skin irritation. J Drugs Dermatol. 2024;23(4): doi:10.36849/JDD.8124.
Topics: Female; Humans; Middle Aged; Administration, Cutaneous; Double-Blind Method; Retinoids; Skin Aging; Treatment Outcome; Tretinoin; Vitamin A; Adult; Controlled Clinical Trials as Topic
PubMed: 38564380
DOI: 10.36849/JDD.8124