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Publikation

Zhang, H.; Lin, S.; Xie, R.; Zhong, W.; Wang, H.; Farag, M. A.; Hussain, H.; Arroo, R. R.; Chen, X.; Xiao, J.; Thermal degradation of (2R, 3R)-dihydromyricetin in neutral aqueous solution at 100 ℃ Food Chem. 435, 137560, (2024) DOI: 10.1016/j.foodchem.2023.137560

In the field of thermal degradation of flavonoids, current studies mainly focused on flavonols. However, the thermal degradation of dihydroflavonols in aqueous solution has received limited attention compared to flavonols. The single C2-C3 bonds of dihydroflavonols, which differs from the C2-C3 double bond in flavonols, may cause different degradation mechanisms. Dihydromyricetin (DMY) is a typical dihydroflavonol with six hydroxyl groups, and possesses various health effects. We explored the thermal degradation of DMY in neutral aqueous solution (pH 7) at 100 ℃. Ultra-performance liquid chromatography combined with photodiode array and electrospray ionization quadrupole-time-of-flight tandem mass spectrometric detection (UPLC-PDA-ESI-QTOF-MS/MS) provided suitable platform for exploring DMY degradation pathways, and negative ion mode was applied. Thermal treatment led to a decline in DMY level with time, accompanied by the appearance of various degradation products of DMY. Degradation mechanisms of DMY included isomerization, oxidation, hydroxylation, dimerization and ring cleavage. The pyrogallol-type ring B of DMY might be initially oxidized into ortho-quinone, which could further attack another DMY to form dimers. In addition, hydroxylation is likely to occur at C-2, C-3 of DMY or DMY dimers, which then further yields ring-cleavage products via breakage of the O1-C2 bond, C2-C3 bond, or C3-C4 bond. The 3-hydroxy-5-(3,3,5,7-tetrahydroxy-4-oxochroman-2-yl) cyclohexa-3,5-diene-1, 2-dione (m/z 333.0244) and unknown compound m/z 435.0925 were annotated as key intermediates in DMY degradation. Four phenolic acids, including 3,4,5-trihydroxybenzoic acid (m/z 169.0136, RT 1.4 min), 2,4,6-trihydroxyphenylglyoxylic acid (m/z 197.0084, RT 1.7 min), 2-oxo-2-(2,4,6-trihydroxyphenyl) acetaldehyde (m/z 181.0132, RT 2.4 min), and 2,4,6-trihydroxybenzoic acid (m/z 169.0139, RT 2.5 min) were identified as the major end products of DMY degradation. In addition, 5-((3,5dihydroxyphenoxy) methyl)-3-hydroxycyclohexa-3,5-diene-1,2-dione (m/z 261.0399, RT 11.7 min) and unidentified compound with m/z 329.0507 (RT 1.0 min) were also suggested to be end products of DMY degradation. These results provide novel insights on DMY stability and degradation products. Moreover, the heat treatment of DMY aqueous solution was found to gradually reduce the antioxidant activities of DMY, and even destroy the beneficial effect of DMY on the gut microbiota composition.
Publikation

Hussain, H.; How can we unlock the full potential of marine biological resources for novel drug discovery in an effective and ethical way? Expert Opinion on Drug Discovery 19, 125-130, (2024) DOI: 10.1080/17460441.2023.2285402

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Publikation

Feng, Q.; Yan, H.; Feng, Y.; Cui, L.; Hussain, H.; Park, J. H.; Kwon, S. W.; Xie, L.; Zhao, Y.; Zhang, Z.; Li, J.; Wang, D.; Characterization of the structure, anti-inflammatory activity and molecular docking of a neutral polysaccharide separated from American ginseng berries Biomedicine & Pharmacotherapy 174, 116521, (2024) DOI: 10.1016/j.biopha.2024.116521

Aim: American ginseng berries, grown in the aerial parts and harvested in August, are a potentially valuable material. The aim of the study was to analyze the specific polysaccharides in American ginseng berries, and to demonstrate the anti-inflammation effect through in vitro and in vivo experiments and molecular docking. Methods: After deproteinization and dialysis, the extracted crude polysaccharide was separated and purified. The structure of the specific isolated polysaccharide was investigated by Fourier Transform infrared spectroscopy (FT-IR), GC-MS and nuclear magnetic resonance (NMR), and anti-inflammatory activity was evaluated using in vitro and in vivo models (Raw 264.7 cells and zebrafish). Molecular docking was used to analyze the binding capacity and interaction with cyclooxygenase-2 (COX-2). Results: A novel neutral polysaccharide fraction (AGBP-A) was isolated from American ginseng berries. The structural analysis demonstrated that AGBP-A had a weight-average molecular weight (Mw) of 122,988 Da with a dispersity index (Mw/Mn) value of 1.59 and was composed of arabinose and galactose with a core structure containing →6)-Gal-(1→ residues as the backbone and a branching substitution at the C3 position. The sidechains comprised of α-L-Ara-(1→, α-L-Ara-(1→, →5)-α-L-Ara-(1→, β-D-Gal-(1→. The results showed that it significantly decreased pro-inflammatory cytokines in the cell model. In a zebrafish model, AGBP-A reduced the massive recruitment of neutrophils to the caudal lateral line neuromast, suggesting the relief of inflammation. Molecular docking was used to analyze the combined capacity and interaction with COX-2. Conclusion: Our study indicated the potential efficacy of AGBP-A as a safe and valid natural anti-inflammatory component.
Publikation

Eshboev, F.; Mamadalieva, N.; Nazarov, P.; Hussain, H.; Katanaev, V.; Egamberdieva, D.; Azimova, S.; Antimicrobial action mechanisms of natural compounds isolated from endophytic microorganisms Antibiotics 13, 271, (2024) DOI: 10.3390/antibiotics13030271

Infectious diseases are a significant challenge to global healthcare, especially in the face of increasing antibiotic resistance. This urgent issue requires the continuous exploration and development of new antimicrobial drugs. In this regard, the secondary metabolites derived from endophytic microorganisms stand out as promising sources for finding antimicrobials. Endophytic microorganisms, residing within the internal tissues of plants, have demonstrated the capacity to produce diverse bioactive compounds with substantial pharmacological potential. Therefore, numerous new antimicrobial compounds have been isolated from endophytes, particularly from endophytic fungi and actinomycetes. However, only a limited number of these compounds have been subjected to comprehensive studies regarding their mechanisms of action against bacterial cells. Furthermore, the investigation of their effects on antibiotic-resistant bacteria and the identification of biosynthetic gene clusters responsible for synthesizing these secondary metabolites have been conducted for only a subset of these promising compounds. Through a comprehensive analysis of current research findings, this review describes the mechanisms of action of antimicrobial drugs and secondary metabolites isolated from endophytes, antibacterial activities of the natural compounds derived from endophytes against antibiotic-resistant bacteria, and biosynthetic gene clusters of endophytic fungi responsible for the synthesis of bioactive secondary metabolites.
Publikation

Cheng, Y.; Zhao, H.; Cui, L.; Hussain, H.; Nadolnik, L.; Zhang, Z.; Zhao, Y.; Qin, X.; Li, J.; Park, J. H.; Wang, D.; Ultrasonic-assisted extraction of flavonoids from peanut leave and stem using deep eutectic solvents and its molecular mechanism Food Chem. 434, 137497, (2024) DOI: 10.1016/j.foodchem.2023.137497

Natural bioactive compounds extracted from agricultural by-products have received considerable attentions. Twenty-two kinds of deep eutectic solvents (DESs) with ultrasonic were screened to extract flavonoids from peanut leave and stem. ChCl-acetic acid (ChCl-Aa) with 1:2 M ratio resulted in more effective extraction of flavonoids compared to other solvents The best extraction conditions were found to be at a 27% water content in DES/H2O, for 43 min with 31:1 g/mL liquid/solid ratio, giving 2.980 mg/g dw of flavonoids through the response surface method. SEM showed that ChCl-Aa had a certain dissociation impact on the sample matrix, while 1H NMR analysis revealed the formation of hydrogen bonds between daidzein and ChCl-Aa. Changes in the H–bond length and number were observed by the B3LYP/6-31G (d,p) level of theory to confirm the experimental spectra. This study reveals that DESs are efficient for obtaining value-added products and could applied to other natural products.
Publikation

Xie, L.; Yan, H.; Han, L.; Cui, L.; Hussain, H.; Feng, Q.; Zhao, Y.; Zhang, Z.; Li, J.; Aziz, S.; He, J.; Wang, D.; Structural characterization and anti-inflammatory activity of neutral polysaccharides from American ginseng Int. J. Biol. Macromol. 248, 125586, (2023) DOI: 10.1016/j.ijbiomac.2023.125586

American ginseng, a precious classic herbal medicine, is used extensively in China for life prolongation purpose. This study aimed to elucidate the structure and anti-inflammatory activity of a neutral polysaccharide isolated from American ginseng (AGP-A). Nuclear magnetic resonance in conjunction with gas chromatography–mass spectrometry were used to analyze AGP-A\'s structure, whereas Raw264.7 cell and zebrafish models were employed to assess its anti-inflammatory activity. According to the results, AGP-A has a molecular weight of 5561 Da and is primarily consisted of glucose. Additionally, linear α-(1 → 4)-glucans with α-D-Glcp-(1 → 6)-α-Glcp-(1→ residues linked to the backbone at C-6 formed the backbone of AGP-A. Furthermore, AGP-A significantly decreased pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) in Raw264.7 cell model. AGP-A in zebrafish model significantly lower the massive recruitment of neutrophils to the neuromast of the caudal lateral line. Inflammation may be relieved by the AGP-A component in American ginseng based on these results. In conclusion, our study shows the structural characterization, remarkable anti-inflammatory properties of AGP-A and its potential curative efficacy as a safe, valid natural anti-inflammatory medicine.
Publikation

Uddin, N.; Muhammad, N.; Ali, S. S.; Ullah, R.; Bari, A.; Hussain, H.; Zhu, D.; Characterization of the genetic variability within Ziziphus nummularia genotypes by phenotypic traits and SSR markers with special reference to geographic distribution Genes 14, 155, (2023) DOI: 10.3390/genes14010155

Understanding the impacts and constraints of climate change on Ziziphus nummularia′s geographical distribution is crucial for its future sustainability. In this study, we analyze information obtained from the field investigation, the distribution and response of climatic changes of Ziziphus nummularia by the use of ArcGIS analysis. The genetic diversity of 180 genotypes from three populations was studied by morphological attributes and simple sequence repeat (SSR). The results showed that the significant bioclimatic variable limiting the distribution of Z. nummularia was the mean temperature (bio 10_18.tif and bio19). Under the current climatic change, the suitable growth region of Z. nummularia is Swat (35.22° N, 72.42° E), while the future distribution would be Buner (34.39° N, 72.61° E), respectively. A total of 11 phenotypic traits were noted and had significant phenotypic variation among the traits. A total of 120 alleles were amplified. The alleles per locus ranged from 2 to 6, averaging 4.42, whereas PIC ranged from 0.33 to 0.79. Within a mean value of 0.67 per locus, expected heterozygosity was 0.57, observed heterozygosity was 0.661, and average gene diversity was 0.49. Flow estimates (6.41) indicated frequent gene flow within genotypes. The clustering, STRUCTURE, and PCoA analysis indicated Swat and Buner migration routes and evolution as well. The results indicated the prevalence of genetic variability and relationships among Z. nummularia across geographical boundaries had retained unique alleles. This may facilitate the development of agronomically desirable cultivars. However, climate change has impacted species distributions, requiring strategies to conserve genetic resources in different areas.
Publikation

Sun, X.; Xu, L.; Yan, H.; Li, P.; Hussain, H.; Liu, J.; Zhang, J.; Wang, D.; Isolation and purification of high polar glycosides from aerial parts of Gynostemma pentaphyllum (Thunb.) Makino by linear gradient counter‐current chromatography coupled with inner‐recycling mode J Sep Sci 46, 2300238, (2023) DOI: 10.1002/jssc.202300238

Gynostemma pentaphyllum (Thunb.) Makino represents the popular health food and supplemental product with broad pharmacological activities. The highly polar glycosides, including flavonoids and saponins, are major effective active components that contain diverse sugar positions and quantities, which result in diverse chemical polarities, making it challenging to separate and isolate these components. The present work described the rapid and efficient linear gradient counter‐current chromatography to preparatively separate glycosides from aboveground parts of G. pentaphyllum. Besides, the ethyl acetate and n‐butanol binary mobile phases were achieved through adjusting associated proportions. Six glycosides, including quercetin‐3‐O‐neohesperidoside (1), kaempferol‐3‐O‐robinobioside (2), kaempferol‐3‐O‐neohesperidoside (3), gypenoside LVI (4), ginsenoside Rb3 (5), and gypenoside XLVI (6), were isolated at the purities greater than 98%. Moreover, electrospray ionization mass spectrometry and nuclear magnetic resonance tandem mass spectrometry were conducted for structural identification. According to our findings, the established linear gradient counter‐current chromatography was an efficient approach to separate the highly polar glycosides from aboveground parts of G. pentaphyllum. Our proposed strategy can be used to separate active compounds from other complex natural products.
Publikation

Rehman, S.; Hussain, A.; Ullah, M.; Ali, E.; Mojzych, M.; Naqvi, S. A. R.; Ali, A.; Ali, M.; Gomaa, E.; Ghoneim, S. S. M.; Mirza, B.; Ring, K. K.; Hussain, H.; Rauf, A.; Rehman, N. U.; Attique, F.; Agrobacterium-mediated genetic transformation of Withania coagulans (Dunal) with rol A genes and its antioxidant potential ACS Omega 8, 41918-41929, (2023) DOI: 10.1021/acsomega.3c07069

In ancient times, Withania coagulans Dunal was used as a herapeutic plant for the treatment of several diseases. This report aims to examine the effect of Agrobacterium tumefactions-mediated transformation of W. coagulans with the rolA gene to enhance secondary metabolite production, antioxidant activity, and anticancer activity of transformed tissues. Before transgenic plant production, the authors designed an efficient methodology for in vitro transformation. In this study, leaf explants were cultured on Murashage and Skoog (MS) media containing different amounts of naphthalene acetic acid (NAA) and benzyl adenine (BA). The best performance for inducing embryogenic callus was in MS medium containing 4 μM NAA and 6.0 μM BA, while the best results for shooting (100%) were obtained at 8 μM benzyl adenine. On the other hand, direct shooting was attained by subculturing leaves on MS medium supplemented with 8 μM benzyl adenine. Prolonged shoots showed excellent in vitro rooting results (80%) with 12 μM indole-3-butyric acid (IBA). The samples were precultivated for 3 days and were followed by 48 h infection with A. tumefaciens strain GV3101 having pCV002. Then, a vector expressed the rol A gene of strain Agrobacterium rhizogenes. Furthermore, three independent transgenic shoot lines and one callus line (T2) were produced and exhibited stable integration of transgene rol A genes, as revealed by PCR analysis. Transgenic strains showed a significant increase in antioxidant potential as compared to untransformed plants. Additionally, LC-MS analysis showed that the transformed strains have a higher withanolide content as compared to untransformed ones. Moreover, the reduced proliferation of prostate cancer cells was observed after treatment with extracts of transgenic plants. Furthermore, these transformed plants exhibited superior antioxidant capability and higher withanolide content than untransformed ones. In conclusion, the reported data can be used to select withanolide-rich germplasm from transformed cell cultures.
Publikation

Ning, F.; Zhu, H.; Yan, H.; Liu, J.; Aziz, S.; Hussain, H.; Song, X.; Xie, L.; Meng, Z.; Cao, G.; Wang, D.; Separation and purification of quinolyridine alkaloids from seeds of Thermopsis lanceolata R. Br. by conventional and pH‐zone‐refining counter‐current chromatography J Sep Sci 46, 2300053, (2023) DOI: 10.1002/jssc.202300053

In this work, the preparative separation of quinolyridine alkaloids from seeds of T. lanceolata by conventional and pH-zone-refining counter-current chromatography. Traditional counter-current chromatography separation was performed by a flow-rate changing strategy with a solvent system of ethyl acetate-n-butanol-water (1:9:10, v/v) and 200 mg sample loading. Meanwhile, the pH-zone-refining mode was adopted for separating 2.0 g crude alkaloid extracts with the chloroform-methanol-water (4:3:3, v/v) solvent system using the stationary and mobile phases of 40 mM hydrochloric acid and 10 mM triethylamine. Finally, six compounds, including N-formylcytisine (two conformers) (1), N-acetycytisine (two conformers) (2), (-)-cytisine (3), 13-β-hydroxylthermopsine (4), N-methylcytisine (5), and thermopsine (6) were successfully obtained in the two counter-current chromatography modes with the purities over 96.5%. Moreover, we adopted nuclear magnetic resonance and mass spectrometry for structural characterization. Based on the obtained findings, the pH-zone-refining mode was the efficient method to separate quinolyridine alkaloids relative to the traditional mode.
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