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Organic and natural deep eutectic solvents for the extraction of bacterial prodiginine biopigments
No full textEfficient bacterial cell wall disruption is a crucial step for obtaining valuable intracellular bacterial natural products like deeply colored prodiginines. Development of greener, environmentally friendly chemical methods is a preferred approach with respect to energy requirements and cost. In this study, we have re-examined extraction of bacterial prodiginines, aiming at making their biotechnological production more sustainable, particularly concerning downstream processing and recovery. For the first time, natural deep eutectic solvents (NADES) were employed to extract prodigiosin (PG) and streptorubin (SB) from lyophilized bacterial biomasses and their extraction efficiency was compared to green organic solvents. Bacterial biomasses of PG-producing Gram-negative Serratia marcescens ATCC 27117 and SB-producing Gram-positive Streptomyces sp. BPS43 were obtained by fermentation, followed by culture centrifugation and freeze-drying. Acidified ethyl acetate (1 % v/v HCl) was the most efficient for PG extraction, yielding 2.36 mg of PG per 100 mg of biomass, corresponding to predicted yields by UV–visible spectroscopy. NADES composed of glycerol:ascorbic acid in 1:1 molar ratio afforded a comparable amount of 2.14 mg PG/100 mg of biomass. For SB extraction, acidified ethyl acetate (1 % v/v HCl) was the most efficient, yielding 1.41 mg SB/100 mg of biomass, while the best NADES composed of betaine:lactic acid in 1:1 molar ratio extracted 17-fold less 0.0834 mg SB/100 mg biomass. While NADES were shown as a greener alternative for PG extraction, thick peptidoglycan layer of Gram-positive Streptomyces sp. proved difficult for treatment with NADES alone, indicating a need for combining NADES with other downstream processing techniques for effective SB extraction
Supplementary material for: Ivković, Đurđa; Senćanski, Milan; Novković, Mirjana; Stojković-Filipović, Jelena; Trifković, Jelena; Ristivojević, Petar; Krstić Ristivojević, Maja (2025). Multidisciplinary Bioanalytical Approach to Assess the Anti-Aging Properties of Flower Petals—A Promising Sustainable Cosmetic Ingredient. in Plants MDPI., 14, 18, 1-24. https://doi.org/10.3390/plants14182869
No full textThe increasing demand for natural, safe, and sustainable ingredients is driving innovation in cosmetic science. This study assessed the anti-aging potential of 17 petal extracts using a multidisciplinary bioanalytical approach. In vitro spectrophotometric assays evaluated anti-wrinkle (anti-elastase), anti-pigmentation (anti-tyrosinase), and antioxidant (DPPH, ABTS) activities, while cytotoxicity was tested on HaCaT keratinocytes. Chemical profiling using HPTLC and UHPLC–MS/MS identified 17 phenolic compounds. For the first time, petals from prairie rose (Rosa setigera Michx.), common peony (Paeonia officinalis L.), horse-chestnut cultivars (Aesculus hippocastanum L., Aesculus × carnea Zeyx.), lilac (Syringa vulgaris), mock-orange (Philadelphus pubescens Loisel), orange lily (Lilium bulbiferum L.), garden tulip (Tulipa gesneriana L.), ivy geranium (Pelargonium × peltatum (L.) L’Hér. ex Aiton), and wallflower (Erysimum × cheiri (L.) Crantz) were studied for their skin anti-aging properties. Prairie rose, peony, and ivy geranium extracts showed strong anti-elastase activity; rose and peony also demonstrated high antioxidant potential, while lilac exhibited significant anti-tyrosinase effects. Key phenolic constituents—caffeic acid, p-coumaric acid, and gallic acid—were further examined via molecular docking, which confirmed their inhibitory properties by revealing inhibition mechanisms. All extracts were confirmed to be non-toxic in zebrafish acute toxicity assays at relevant concentrations. This integrative strategy effectively links chemical composition with biological activity, offering valuable insight into the development of safe, plant-derived anti-aging agents for sustainable cosmetic applications.Supplementary material for: [https://doi.org/10.3390/plants14182869]Related to published version: [https://cherry.chem.bg.ac.rs/handle/123456789/7290
Assessing metal contamination using bumblebees and honey bees – Complementary roles in biomonitoring
No full textMetal pollution poses a significant risk to ecosystems and public health, which is why effective monitoring tools are needed. Honey bees (Apis mellifera) are often used as biomonitors due to their large foraging range and ease of sampling. However, as they are domesticated, eusocial insects with perennial colonies, they may not be representative of all bee species. In this study, the bufftailed bumblebee (Bombus terrestris), a native wild pollinator with distinct ecological characteristics, is evaluated as a complementary or alternative biomonitor. Bumblebees forage over shorter distances and have a more diverse diet, offering the potential for higher spatial resolution in pollution studies. Honey bee and bumblebee colonies were sampled near Aachen, Germany. Bumblebees showed higher concentrations of S, Cu, Zn, As, Se, Mo and Ba compared to honey bees. Honey bees had higher concentrations of Al, K, Ca, Rb, Cd, Sn and Cs compared to bumblebees. Bumblebees generally collect more nutrient-rich food, which is confirmed by the higher proportion of essential and beneficial elements in bumblebees (S, Cu, Zn and Se) compared to honey bees (K and Ca). Contamination indices showed similar pollution levels for most elements, although bumblebees showed localized pollution sources. Both species are effective biomonitors: honey bees provide broader area assessments, while bumblebees offer finer spatial resolution and operate at lower temperatures. Together, they enable a multi-level monitoring approach, with honey bees indicating general pollution trends and bumblebees detecting local sources
Sintetička studija waihoensena: sekvencione anelacije ciklopentanovih prstenova
No full textSprovedeno istraživanje omogućilo je identifikaciju ključnih faktora koji utiču na reaktivnost i selektivnost policikličnih sistema, kao i postavljanje osnova za dalji razvoj efikasnijih strategija u sintezi trikinanskih i tetrakinanskih struktura. Dobijeni rezultati imaju značaj ne samo u kontekstu konkretne sinteze, već i u širem razumevanju hemijskog ponašanja datih jedinjenja u reakcijama funkcionalne transformacije
Ameliorative Effect of Banana Lectin in TNBS-Induced Colitis in C57BL/6 Mice Relies on the Promotion of Antioxidative Mechanisms in the Colon
No full textBackground: The global burden of inflammatory bowel diseases (IBDs), including ulcerative colitis and Crohn’s disease, is constantly rising. As IBDs significantly reduce patients’ quality of life, prevention and efficient treatment of IBDs are of paramount importance. Although the molecular mechanisms underlying IBD pathogenesis are still not completely understood, numerous studies indicate the essential role of oxidative stress in the progression of the diseases. Objective: The aim of this study was to investigate whether prophylactic administration of recombinant banana lectin (rBanLec) could positively affect antioxidative mechanisms in the colon and thus prevent or alleviate the severity of experimental colitis induced in C57BL/6 mice. Methods: The prophylactic potential of rBanLec, a mannose-binding lectin with immunomodulatory properties, was investigated in a model of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in C57BL/6 mice. Mice received rBanLec at various doses (0.1, 1 and 10 μg/mL) before the induction of colitis. The severity of the disease was assessed by weight loss and reduction in colon length, and correlated with histopathological findings, cytokine milieu, and oxidative stress markers in the colon. Results: The obtained results revealed that pretreatment with a low dose of rBanLec (0.1 μg/mL) significantly reduced the severity of TNBS-induced colitis, as indicated by reduced weight loss, less severe histopathological damage, and a favorable anti-inflammatory cytokine milieu (increased IL-10 and TGFβ). In addition, rBanLec pretreatment improved the activity of antioxidant enzymes (SOD, CAT, and GST) and reduced markers of oxidative stress such as nitric oxide levels at the peak of the disease. In contrast, higher doses of rBanLec exacerbated inflammatory responses. Conclusions: Our findings indicate that at low doses rBanLec can alleviate the severity of colitis by modulating oxidative stress and promoting anti-inflammatory cytokine responses, positioning rBanLec as a potential candidate for treating IBDs
XRD i SEM-EDS analiza ferosilicidnih materijala nepoznatog porekla
No full textTema ovog rada je analiza dva uzorka nepoznatog porekla. Reč je o uzorcima sive boje, metaličnog sjaja. Za analizu uzoraka su korišćene dve analitičke tehnike: rendgenska difrakciona analiza i skenirajuća elektronska mikroskopija sa energetsko-disperzivnom spektroskopijom. Rendgenskom difrakcionom analizom je ustanovljeno da u oba uzorka dominiraju gvožđe-silicidne faze, tako da u prvom uzorku dominira gupejit (Fe3Si), dok u drugom uzorku dominira zifengit (Fe5Si3). Skenirajućom elektronskom mikroskopijom sa energetsko-disperzivnom spektroskopijom je u oba uzorka identifikovano više različitih faza. Analizom podataka dobijenih ovim dvema tehnikama je ustanovljeno da analizirani uzorci verovatno nisu prirodnog porekla, odnosno da je reč o metalurškim proizvodima. S obzirom da informacije u vezi sa mestom i neposrednom okolinom nalaska uzoraka nisu poznate, nije bilo moguće jednoznačno utvrditi poreklo. Bez obzira na to, za oba uzorka su određeni hemijski sastav i struktura, što je svakako i bio cilj ovog rada
Spektrofotometrijska analiza fiziološkog odgovora biljke Plantago lanceolata na stres izazvan arsenom
No full textZagađenje vodenih ekosistema i obradivih površina metalima najčešće je posledica antropogenog dejstva, može biti izazvana rudarstvom, upotrebom đubriva, ali i različitim hemijskim akcidentima.
Cilj istraživanja je utvrđivanje kontaminacije zemljišta arsenom na model sistemu biljke Plantago lancelata (uskolisna bokvica) korišćenjem spektrofotometrije lista. Takođe, cilj je da se spektrofotometrijskom analizom utvrdi potencijalno specifični vegetacioni indeks za kontaminaciju zemljišta arsenom kako bi se tako dobijeni podaci mogli koristiti za buduća merenja spektroskopskim kamerama. Tako bi se potencijalno mogla omogućiti brza detekcija ili monitoring hemijskog zagađenja zemljišta arsenom koristeći za to biljke i spektrofotometriju.
Biljna vrsta P. lancelata je odabrana kao model sistem za ovaj rad na osnovu svoje široke geografske rasprostranjenosti i zbog jednostavnog uzgoja u veštačkim uslovima. Tretiranje je vršeno vodenim rastvorom arsen (III)-hlorida koncentracije 500 ppm i to na dva načina: u stiroporskim kontejnerima u lodni i u hidroponskim saksijama. Nakon tretmana snimani su apsorpcioni, transmisioni i refleksioni spektri u oblasti 330-1100 nm pomoću spektrofotometra za lišće tokom tri dana. Uporedno su analizirani spektrofotometrijski podaci za tretirane i kontrolne biljke. U cilju dobijanja pouzdanih predikcionih podataka korišćeni su postojeći vegetacioni indeksi, ali su i predloženi više specifični novi vegetacioni indeksi za kontaminaciju zemljišta arsenom
Perturbational and Variational Energy Decomposition Analysis on Hydrogen Bonds of Coordinated Glycine and Water Molecule
No full textThree types of hydrogen bonds of coordinated glycine and water had been investigated: NH/O of α-amino group, O1/HO involving oxygen coordinated to the metal ion (O1), and O2/HO involving α-carbonyl oxygen (O2). Various glycine complexes were investigated: octahedral cobalt(III) and nickel(II), square pyramidal copper(II), and square planar copper(II), palladium(II), and platinum(II) complexes. Nature of these three hydrogen bond types was analyzed using symmetry-adapted perturbation theory (SAPT) and variational energy decomposition analysis (EDA) method (TPSS−D3/def2-TZVPP). The results of the EDA decomposition are in good agreement with the reliable SAPT2+3/def2-TZVPP and its total interaction values with CCSD(T)/CBS energies. Electrostatic interaction is generally the dominant attractive energy term in most of the interactions, followed by orbital relaxation, and lastly dispersion as the weakest. We compared EDA results of various complexes to determine the effects of complex charge, metal oxidation, coordination, and atomic number on the energy decomposition terms. The complex charge influences the values of decomposition terms the most, followed by metal oxidation and coordination number, while atomic number effects them the least. All complex and metal changes have a more significant effect on the results of NH/O and O1/HO than O2/HO interactions, due to its location further away from the metal ion
A Formal 1,2-Stevens Rearrangement of Thioester Ylides as a Single-Atom Molecular Editing Tool
No full textA rhodium-catalyzed reaction of thioesters with diazo reagents was recognized as a powerful and unprecedented tool for single-atom molecular editing by the insertion of a single carbon atom into the C(O)─S thioester bond, thereby leading to various α-thioketones possessing a quaternary carbon atom. A selective and precise defunctionalization of the polyfunctionalized products further demonstrated the synthetic utility of the reaction for the synthesis of more common structural classes of compounds
The Effect of the Substituent's Nature on the Crystallographic and Quantum-Chemical Profile of the Fluorine–Fluorine Interaction
No full textThe investigation of the intermolecular profile of F···F interactions is based on the statistical analysis of data obtained from the Cambridge Structural Database, quantum theory of atoms in molecules, and quantum-mechanical calculations. The influence of the nature of the substituents bound to the interacting fluorine atoms is also investigated. The geometric parameters used to define F···F interactions (bond length, bond angle, and torsion angle) indicate the suitability of F···F interactions for a supramolecular compromise with other interactions from the environment. Regardless of the nature of the substituent, the antiparallel orientation of the interacting groups and long distances (longer than 2.9 Å) represent the specificity of these interactions, which makes them suitable for forming a large number of simultaneous interactions with species from the environment. The shallow minima in the energy profiles, in the range from 3.0 to 3.5 Å, indicate weak noncovalent interactions, as well as the possibility of F···F interactions to easily adapt to the geometries of the surrounding interactions. Changes in the geometry and in the substituents on the aromatic ring have a significantly greater influence on the strength of F···F interactions compared to the case where the interacting fluorine atoms are bound to alkyl groups