Nuclear Magnetic Resonance Spectral Analysis Research Articles

Dibenzoxanthene-β-lactam hybrids as potential antioxidant and anticancer agents: Synthesis, biological evaluation, and docking study

In this study, we designed and synthesized a series of β-lactam compounds bearing 14-phenyl-14H-dibenzo[a,j]xanthene moiety attached to the N-1 position of the β-lactam ring through a [2 + 2] cycloaddition process. All the synthesized compounds have been characterized by elemental analysis, Fourier-transform infrared (FT-IR) and nuclear magnetic resonance (1H NMR and 13C NMR) spectral analysis. These derivatives were evaluated for their anticancer and antioxidant activities. The in vitro anticancer activity of new compounds was examined against MCF-7 (breast cancer), HepG2 (liver hepatocellular carcinoma), and TC-1 (mouse lung epithelial) cell lines by 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay. Notably, compounds 4c, 4e and 4 g demonstrated significant anticancer activity against TC-1 cell line. Additionally, compounds 4c, 4f and 4 g exhibited promising levels of efficacy against the MCF-7 cell line. The diphenylpicrylhydrazyl (DPPH) radical scavenging assay indicated that 4h and 4i are more potent antioxidant agents than the Vitamin C, while 4a, 4b, 4c, and 4j exhibited moderate antioxidant capabilities. Furthermore, the docking simulations are consistent with the biological assay results, indicating that the hybrids may bind to protein targets through hydrogen bonding and other nonvalent interactions.

Chemosensor material as a metal–organic framework with potassium-based perylene tetracarboxylic acid for copper and lead detection

Heavy metal ions stand out as highly toxic pollutants, playing a pivotal role in various human diseases. Consequently, the development of advanced detection methods becomes imperative for global public health. A proven and effective strategy for metal ion detection involves the use of fluorescent chemosensors. In this context, we synthesized metal–organic frameworks (MOFs) based on perylene to create potassium-based MOFs functioning as an efficient detection probe for metal ion detection. Proton nuclear magnetic resonance (NMR) spectral analysis revealed only two distinct types of hydrogen signals are observed from K4PTC, and no hydrogen signals originating from any residual K4PTC are detected. Similarly, In the 13C NMR spectra, the most downfield signal observed at 176.9 ppm is conveniently assigned to the carbonyl carbon of the K4PTC. The probe displayed diminished absorbance and fluorescence intensity upon the introduction of Cu2+ and Pb2+, suggesting K4PTC’s potential as a sensor for detecting these metal ions. The above findings indicate that loading metal ions into the K4PTC system weakens the oxygen-potassium interaction, signifying the interaction between the metal ions and our probe. Interestingly, the limit of detection (LOD) for our sensor material is highly effective for detecting these metal ions. Consequently, this research serves as a significant reference for the sensitive monitoring of metal pollutants in the environment.

Thermodynamic properties and CO2 absorption performance of the deep eutectic solvent (dipropylene glycol + 1, 2-propylenediamine) + H2O

This work selected dipropylene glycol (DPG) as the hydrogen bond donors to amalgamate with 1, 2-propylenediamine (1,2-PDA) as hydrogen bond acceptors, and introduced water into this system, adjusting the molar ratios of components to modulate the physicochemical properties of deep eutectic solvents. The discourse commences with the fundamental exploration of solution density and viscosity, delving into the microscopic principles of intermolecular interactions, and scrutinizing factors mitigating amine loss in the process of CO2 sequestration. Optimizing the performance of amine solutions by introducing alcohol substances and subsequently incorporating water to enhance their CO2 absorption capacity is undertaken. Based on the measured density and viscosity data of (DPG + 1,2-PDA) + H2O, fitting and molecular simulation calculations are performed to ascertain the most potent binding forms. Hydrogen nuclear magnetic resonance, Raman, and Fluorescence spectral analyses were also carried out to demonstrate the presence of intermolecular hydrogen bonding in the form of –OH···N(H2)- between DPG and 1,2-PDA. Ultimately, the solution undergoes CO2 absorption capacity determination to assess its absorptive efficacy.

Material design of geopolymers using calcined allophane

As kaolinite, the main material of geopolymers, is not produced in East Asia and elsewhere, it is necessary to find alternative materials to replace kaolinite. The authors therefore investigated the preparation conditions and optimum curing temperature of geopolymers using allophane, which is not used as a cementitious material. Based on compressive strength and internal temperature history results, specimens were prepared by mixing allophane calcined at 800 °C for 3 h with an alkaline solution adjusted to a Na2O/SiO2 ratio of one at a water-to-powder ratio of two. Powder X-ray diffraction and nuclear magnetic resonance spectral analyses of specimens indicated that amorphous geopolymers with a three-dimensional structure were produced from calcined allophane. As for the optimum curing temperature, the samples cured at 20 °C showed the best strength development properties. On the other hand, specimens cured at 80 °C showed a temporary decrease in compressive strength as zeolite formation progressed with increasing curing time. Since 20 °C is the optimal curing condition, we conclude that geopolymers that can be used for on-site curing can be produced by using calcined allophane.

Magnetic resonance imaging: an innovative approach to observe rare metal extraction using ionic liquid.

In the present work, a novel approach has been made to evaluate the extraction mechanism of neodymium (Nd) using trihexyl-tetradecyl-phosphonium benzoate (TTPB) ionic liquid through nuclear magnetic resonance (NMR) techniques. A detailed study on the interactions between the extractant (Nd) and the ionic liquid (IL) is presented. The 1H NMR spectral analysis confirmed that Nd extraction took place through the benzoate anion. Furthermore, the NMR relaxation time of the anion is greatly affected affirming that Nd extraction indeed took place through the benzoate anion. This change in the relaxation time caused by the Nd ion on the protons in the anion and cation in TTPB has been used to visualize the extraction mechanism using 1H MRI. A strong change in the image intensity with respect to the time observed in the IL phase validates the extraction of Nd from the aqueous phase into the IL phase. Also, combining the 1H NMR, diffusion coefficient, Karl-Fischer and ultraviolet-visible absorption spectroscopic (UV-Vis) results, we have elucidated the co-ordination structure around Nd during the extraction process.

Formulation of Ensulizole with Beta-Cyclodextrins for Improved Sunscreen Activity and Biocompatibility

In today's context, prolonged exposure to sunlight is widely recognized as a threat to human health, leading to a range of adverse consequences, including skin cancers, premature skin aging, and erythema. To mitigate these risks, preventive actions mainly focus on advocating the application of sunscreen lotions and minimizing direct exposure to sunlight. This research study specifically centered on ensulizole (ENS), a prominent ingredient in sunscreens. The objective was to create inclusion complexes (ICs) with Beta-cyclodextrin (B–CD) and its hydroxypropyl derivatives (H–CD). Using phase solubility measurements, we determined that both B–CD and H–CD form 1:1 stoichiometric ICs with ENS. Proton nuclear magnetic resonance spectral (1H NMR) analysis confirmed that the phenyl portion of ENS is encapsulated within the B–CD cavity. Significant changes in surface morphology were observed during the formation of these ICs compared to ENS and CDs alone. Quantum mechanical calculations were employed to further support the formation of ICs by providing energy data. Particularly, the photostability of the ENS:B–CD ICs remained intact for up to four hours of UV exposure, with no significant alterations in the structure of ENS. Furthermore, comprehensive biocompatibility assessments yielded encouraging results, suggesting the potential application of these inclusion complexes in cosmetics as a UVB sunscreen. In summary, our research underscores the successful creation of inclusion complexes characterized by enhanced photostability and safe biocompatibility.

Biodiesel from Dunaliella salina Microalgae Using Base Catalyzed Transesterification – An Assessment through GC/MS, FTIR and NMR Studies

Algal biofuels are a promising renewable feedstock to produce energy that can supplement future energy demands greatly. The present study aims to utilize Dunaliella salina, a hypersaline, unicellular greenish-orange micro-algae, to produce bio-oil. F/2 nutrient media and trace metal and vitamin solution under carbon-dioxide-rich conditions were used to cultivate the microalgae. Ultrasonic extraction method at 60 Hz for 90 min isolated 650 mL of bio-oil. A single-stage based-catalyzed transesterification process with methanol and sodium hydroxide yielded 380 mL of Pure Dunaliella salina biodiesel at % an extraction efficiency of 87%. The Phytochemical screening on the cultivated Dunaliella sp. was performed to understand its feasibility to be used as a fuel for IC engines. Furthermore, the obtained biodiesel was characterized using Fourier Transform Infrared Spectrometer (FTIR), Gas Chromatography Mass Spectrometer (GCMS), and Nuclear Magnetic Resonance (NMR) spectral analysis.

FOSAMPRENAVIR CALCIUM LOADED DENDRIMERS: FORMULATION DEVELOPMENT, EVALUATION AND HEMOLYTIC TOXICITY STUDIES

Objective: Dendrimers are the three-dimensional polymeric architectural motif which bestows an advanced platform for drug delivery and drug targeting. Dendrimers are a novel cargo system that can accommodate larger amounts of the drug in its structure by conjugating the drug with terminal amine functional groups. The present work was designed to develop Fosamprenavir calcium-loaded 5th generation poly (propylene imine) (5G PPI) dendrimers for effective treatment of Human immunodeficiency virus. Methods: The drug loading was carried out using a direct method with continuous stirring for 48 h. The sample was characterized using different analytical techniques and also evaluated for drug entrapment, drug release, and release kinetics. The hemolytic toxicity studies were also performed and evaluated based on % hemolysis and surface morphology of RBCs after incubating with the prepared formulation. Results: The Fourier transform infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectral analysis confirms the conjugation of the Fosamprenavir calcium and dendrimers. Differential scanning calorimetry analysis (DSC) also confirmed the conjugation of the drug with dendrimers. Scanning electron microscopy (SEM) images showcased the spherical floral arrangement of the dendrimer structure. The drug entrapment studies revealed 69.83±0.31% of the drug encapsulated in the dendrimer structure. The drug release studies showed 80.18±0.65% in phosphate buffer pH 7.4 and 68.09±1.78% in acetate buffer pH 5.0. The drug release kinetics showed that the Higuchi release pattern was followed for the release pattern of pH 5 and pH 7.4. The hemolysis study revealed that the conjugation of the drug with 5G PPI dendrimers drastically reduces the hemolysis. Conclusion: Thus, from the studies, it can be concluded that an efficient drug delivery system can be developed for the anti-retroviral drug Fosamprenavir calcium by loading on 5G PPI dendrimers.

Solid Dispersions of Gefitinib with D-α-Tocopherol Polyethylene Glycol-1000 Succinate and 2-Hydroxypropyl β-Cyclodextrin Complex Improved Their Solubility, Dissolution and Apoptosis against A549 Cells

This study focuses on the development and characterization of solid dispersions (SDs) of Gefitinib (GEF) to improve its aqueous solubility and therapeutic activity against lung cancer. SDs were prepared by the co-precipitation method with tocopheryl-polyethylene-glycol succinate-1000 (TPGS) (F1), sodium lauryl sulfate (SLS) (F2) and complexation of F1 with hydroxypropyl β-cyclodextrin (HP-β-CD) (F3). Optimal formulations (F1 and F3) were used against A549 cells to determine the apoptosis, expressions of p53 and caspases. F3 has shown the highest solubility (1271.21 µg/mL), followed by F1 (1003.69 µg/mL), F2 (707.81 µg/mL) and GEF pure (303.85 µg/mL) in 0.1N HCl. Dissolution at 1.2 pH significantly enhanced the release from F3 (99.19%), followed by F1 (94.76%), F2 (85.70%) and GEF pure (37.26%) during 120 min. Complexation of GEF–TPGS with HP-β-CD significantly improved drug release with high dissolution efficiency (78.57%) in 24.9 min of mean dissolution time. Differential scanning calorimetry revealed crystalline to amorphous conversion of GEF in SDs, which was confirmed by scanning electron microscopy. Fourier transform infrared and proton nuclear magnetic resonance spectral analysis revealed no interaction between GEF and excipients. The IC50 values were 2.239, 3.135 and 4.471 µM for F3, F1 and GEF pure, respectively, against A549 cells. Increased expressions of p53 (5.9-, 4.6- and 3.04-fold), caspase-3 (5.38-, 3.78- and 3.01-fold) and caspase-9 (5.35-, 3.76- and 2.47-fold) in the case of F3, F1 and GEF pure, respectively, as compared to the untreated A549 cells indicated improved apoptotic potential of the SDs. TPGS SDs and their complexation with HP-β-CD improved the solubility, dissolution and efficacy of GEF against A549 cells. So, they can be a suitable alternative to the conventional GEF formulations against non-small-cell lung cancers.

Inhibitory activity of lignanamides isolated from hemp seed hulls(Cannabis sativa L.) against soluble epoxide hydrolase

Soluble epoxide hydrolase (sEH) is a therapeutic target for inflammation. In the present study, we isolated one new (1) and four known (2–5) compounds from the ethyl acetate fraction of hemp seed hulls. Their structures were elucidated as lignanamides via nuclear magnetic resonance and mass spectral analyses. All five compounds inhibited sEH activity, with half-maximal inhibitory concentrations of 2.7 ± 0.3 to 18.3 ± 1.0 μM. These lignanamides showed a competitive mechanism of inhibition via binding to sEH, with ki values below 10 μmol. Molecular simulations revealed that compounds 1–5 fit stably into the active site of sEH, and the key amino acid residues participating in their bonds were identified. It was confirmed that the potential inhibitors 4 and 5 continuously maintained a distance of 3.5 Å from one (Tyr383) and four amino (Asp335, Tyr383, Asn472, tyr516) residues, respectively. These findings provide a framework for the development of naturally derived sEH inhibitors.

MagMet: A fully automated web server for targeted nuclear magnetic resonance metabolomics of plasma and serum.

Nuclear magnetic resonance (NMR) spectral analysis of biofluids can be a time-consuming process, requiring the expertise of a trained operator. With NMR becoming increasingly popular in the field of metabolomics, there is a growing need to change this paradigm and to automate the process. Here we introduce MagMet, an online web server, that automates the processing and quantification of 1D 1 H NMR spectra from biofluids-specifically, human serum/plasma metabolites, including those associated with inborn errors of metabolism (IEM). MagMet uses a highly efficient data processing procedure that performs automatic Fourier Transformation, phase correction, baseline optimization, chemical shift referencing, water signal removal, and peak picking/peak alignment. MagMet then uses the peak positions, linewidth information, and J-couplings from its own specially prepared standard metabolite reference spectral NMR library of 85 serum/plasma compounds to identify and quantify compounds from experimentally acquired NMR spectra of serum/plasma. MagMet employs linewidth adjustment for more consistent quantification of metabolites from higher field instruments and incorporates a highly efficient data processing procedure for more rapid and accurate detection and quantification of metabolites. This optimized algorithm allows the MagMet webserver to quickly detect and quantify 58 serum/plasma metabolites in 2.6 min per spectrum (when processing a dataset of 50-100 spectra). MagMet's performance was also assessed using spectra collected from defined mixtures (simulating other biofluids), with >100 previously measured plasma spectra, and from spiked serum/plasma samples simulating known IEMs. In all cases, MagMet performed with precision and accuracy matching the performance of human spectral profiling experts. MagMet is available at http://magmet.ca.

Nematicidal Coumarins from Cnidium monnieri Fruits and Angelica dahurica Roots and Their Physiological Effect on Pine Wood Nematode (Bursaphelenchus xylophilus).

Pine wood nematode (PWN), Bursaphelenchus xylophilus, is a major pathogen of pine wilt disease (PWD), which is a devastating disease affecting pine trees. Eco-friendly plant-derived nematicides against PWN have been considered as promising alternatives to control PWD. In this study, the ethyl acetate extracts of Cnidium monnieri fruits and Angelica dahurica roots were confirmed to have significant nematicidal activity against PWN. Through bioassay-guided fractionations, eight nematicidal coumarins against PWN were separately isolated from the ethyl acetate extracts of C. monnieri fruits and A. dahurica roots, and they were identified to be osthol (Compound 1), xanthotoxin (Compound 2), cindimine (Compound 3), isopimpinellin (Compound 4), marmesin (Compound 5), isoimperatorin (Compound 6), imperatorin (Compound 7), and bergapten (Compound 8) by mass and nuclear magnetic resonance (NMR) spectral data analysis. Coumarins 1-8 were all determined to have inhibitory effects on the egg hatching, feeding ability, and reproduction of PWN. Moreover, all eight nematicidal coumarins could inhibit the acetylcholinesterase (AChE) and Ca2+ ATPase of PWN. Cindimine 3 from C. monnieri fruits showed the strongest nematicidal activity against PWN, with an LC50 value of 64 μM at 72 h, and the highest inhibitory effect on PWN vitality. In addition, bioassays on PWN pathogenicity demonstrated that the eight nematicidal coumarins could effectively relieve the wilt symptoms of black pine seedlings infected by PWN. The research identified several potent botanical nematicidal coumarins for use against PWN, which could contribute to the development of greener nematicides for PWD control.

The Moonlighting Function of Soybean Disordered Methyl-CpG-Binding Domain 10c Protein.

Intrinsically disordered proteins (IDPs) are multifunctional due to their ability to adopt different structures depending on the local conditions. The intrinsically disordered regions of methyl-CpG-binding domain (MBD) proteins play important roles in regulating growth and development by interpreting DNA methylation patterns. However, whether MBDs have a stress-protective function is far from clear. In this paper, soybean GmMBD10c protein, which contains an MBD and is conserved in Leguminosae, was predicted to be located in the nucleus. It was found to be partially disordered by bioinformatic prediction, circular dichroism and a nuclear magnetic resonance spectral analysis. The enzyme activity assay and SDS-PAGE results showed that GmMBD10c can protect lactate dehydrogenase and a broad range of other proteins from misfolding and aggregation induced by the freeze-thaw process and heat stress, respectively. Furthermore, overexpression of GmMBD10c enhanced the salt tolerance of Escherichia coli. These data validate that GmMBD10c is a moonlighting protein with multiple functions.

Preparation and Characterization of Polyurethane Rigid Foam Nanocomposites from Used Cooking Oil and Perlite

Modern chemical industries trend towards industrial ecology to achieve a circular economy, because of increasing environmental and economic awareness jointly. One of the most important of these industries is polyurethane, accompanied by more and more interest in using renewable polyols. The study focuses on synthesizing and characterizing polyurethane rigid foams formulated by replacing 40%, 60%, and 100% of a petrochemical polyol with a bio-polyol derived from used cooking oil, and introducing perlite and modified perlite nanoparticles into the bio-polyol. The products were evidenced by transmission electron microscopy (TEM), Fourier transform infrared (FTIR), nuclear magnetic resonance spectral analyses, thermogravimetric analysis (TGA), and scanning electron microscopy equipped with energy-dispersive spectroscopy. The results indicate that the hydroxide value and viscosity at 25°C of the bio-polyol were around 456 ± 30 mg KOH/g and 148 mPa s. Bio-polyol blends of 40% and 60% had no significant effect on the thermal properties of polyurethane systems. The lowest value of char yield was observed for the sample with a 100% bio-polyol content of 2.3%. The beneficial effects of both perlite and modified perlite particles on the 100% bio-polyol-based foam were observed as having an effective role in improving thermal stability and reconstructing cellular structure. The yield char increased to 13.2%, 14%, 14.7%, and 15% for the two filler contents 2.5% and 5%. However, the new bio-polyol has a fairly good value in industrial construction, and the perlite particles have enhanced and improved this value.

Comparison of phosphorus species in livestock manure and digestate by different detection techniques

Phosphorus (P) species characterize the effectiveness of the P fertilizer. In this study, the P species and distribution in different manures (pig manure, dairy manure and chicken manure) and their digestate were systematically investigated through combined characterization methods of Hedley fractionation (H2OP, NaHCO3-P, NaOH-P, HCl-P, and Residual), X-ray diffraction (XRD) and nuclear magnetic resonance (NMR) techniques. The results from Hedley fractionation showed that >80 % of P in the digestate was inorganic and the HCl-P content in manure increased significantly during anaerobic digestion (AD). XRD manifested that insoluble hydroxyapatite and struvite belonging to HCl-P were presented during AD, which was in agreement with the result of Hedley fractionation. 31P NMR spectral analysis revealed that some orthophosphate monoesters were hydrolyzed during AD, meanwhile the orthophosphate diester organic phosphorus like DNA and phospholipids content has increased. After characterizing P species by combining these methods, it was found that chemical sequential extraction could be an effective way to fully understand the P in livestock manure and digestate, with other methods used as auxiliary tool depending on the purpose of studies. Meanwhile, this study provided a basic knowledge of utilizing digestate as P fertilizer and minimizing the risk of P loss from livestock manure. Overall, applying digestates can minimize the risk of P loss from directly applied livestock manure while satisfying plant demands, and is an environmentally friendly P fertilizer.

A greener approach of synthesis of new 2-chloro-1,3,2-diazaphosphinin-4-one-2-oxide derivatives

In this work, we describe a novel, easy and green method for the synthesis of diazaphosphinine derivatives. The new diazaphosphinines were prepared by condensation of phosphorus oxychloride with the corresponding benzamides under reflux in acetone with moderate to good yields. The structures of the new compounds were confirmed on the basis of their infrared and nuclear magnetic resonance spectral data (1H, 13C, and 31P), MS, and elemental analysis.

NMR Analysis of Mammalian Glycolipids.

Mammalian glycolipids play a variety of roles, often coupled with interactions with endogenous and exogenous molecules. The interactions can induce intracellular signaling and are the means by which glycolipids express biological phenotypes. Insights into the structure-function relationships of glycolipids (both glycan and lipid moieties) provide the basis for gaining an understanding of the mechanisms at play, an important area for further study. Solution nuclear magnetic resonance (NMR) spectroscopy is a unique and powerful method employed to provide, at the atomic level, structural information on glycolipids and other biomolecules in solutions. This chapter briefly describes how we measure NMR spectra of glycolipids and the information gained from NMR spectral analysis.

One step protocol and green synthesis of 2-N,N-dimethylamino-3-alkyl(aryl)-2-oxido-1- hydro-2-benzo[1,3,2]diazaphosphinine-4-one derivatives

ABSTRACT. 2-N,N-dimethylamino-2-oxido-3-alkyl(aryl)-1-hydro-2-benzo[1,3,2]diazaphosphinin-4-one (2) derivatives are synthesized by one pot reaction by reacting equimolar quantities of anthranilic acid, primary amine, and N,N-dimethylphosphoramic dichloride under reflux of ethanol with good yields. The structure of the compounds were established on the basis of their infrared, nuclear magnetic resonance spectral data (1H NMR, 13C NMR and 31P NMR), mass spectrometry, and elemental analysis.
 
 KEY WORDS: Anthranilic acid, N,N-Dimethylphosphoramic dichloride, Diazaphosphinine
 Bull. Chem. Soc. Ethiop. 2022, 36(4), 859-864. 
 
 DOI: https://dx.doi.org/10.4314/bcse.v36i4.11

Identification of Linomide Derivatives as Potential Anticancer Therapeutics using Molecular Docking Studies.

12 analogs bearing a structural similarity to Linomide, a bonafide anticancer agent were synthesized wherein cyclization of substituted dianilides rendered 4-hydroxyquinolin-2(1H)-ones that were subjected to a Mannich reaction to yield 4-hydroxy-3-(substituted-1-ylmethyl) quinolin-2(1H)-one analogs. Characterization was performed using IR, 1H nuclear magnetic resonance and 13C NMR spectral analysis. Subsequently, in vitro anticancer studies revealed that Compound 4b showed maximum cytotoxicity with IC50 values of 1.539 μM/ml and 1.732 μM/ml against A549 and K562 cell lines respectively. This, however, is lower in comparison with standard Paclitaxel (IC50 values of 0.3 μM/ml for both cell lines). Surprisingly, docking studies at the active site of EGFRK revealed Compound 4b possessed a MolDock Score of -110.2253 that is highly comparable to the standard 4-anilinoquinazoline (MolDock Score of -112.04). Our computational and biological data thus provides an insight on the cytotoxicity of these derivatives and warrants future research that can possibly lead to the development of potent anticancer therapeutics.

Macrolactin Metabolite Production by Bacillus sp. ZJ318 Isolated from Marine Sediment.

A total of 172 microbial strains were screened and isolated from Arctic Ocean marine sediments at a depth of 42 ~ 3,763m. A microorganism with strong antibacterial activity against Staphylococcus aureus was identified as Bacillus sp. ZJ318 according to the results of 16S rDNA sequencing and phylogenetic tree analyses. Bioactivity-guided isolation of the new/novel metabolite in the ethyl acetate (EA) extract obtained from the fermentation broth of this strain was followed by chromatographic fractionation and subsequent HPLC purification, leading to the isolation of one known macrolactin. The chemical structure of the macrolactin, which indicated macrolactin J isolation from marine microorganisms for the first time, was assigned based on a high-resolution electrospray ionization mass spectrometer system (HR-EMI-MS), nuclear magnetic resonance (NMR) spectral analyses, and a literature review. To improve macrolactin J production, the corresponding effects of nitrogen sources were investigated, and (NH4)2SO4 was determined to produce the best effect. In addition, the optimal culture conditions were determined by an orthogonal experiment. Under these conditions, the yield of macrolactin J was increased to 2.41mg/L, which was 2.2 times the original yield. This work lays a foundation for follow-up mechanistic and application research on macrolactin J.