116 research outputs found
Phytochemical Investigation of Egyptian Spinach Leaves, a Potential Source for Antileukemic Metabolites: In Vitro and In Silico Study
Spinacia oleracea L., Amaranthaceae, leaves cultivated in Egypt demonstrated a potential antileukemic activity against the chronic myeloid leukemia, K562 cell line. Thus, the aim of this study is to carry out a phytochemical investigation of S. oleracea leaves as well as the isolation of its antileukemic phytoconstituents. Phytochemical investigation of S. oleracea leaves resulted in the isolation of seventeen known compounds. The biological study revealed that compounds hexaprenol, phytol, and 18-[(1-oxohexadecyl) oxy]-9-octadecenoic acid exhibited a remarkable antiproliferative activity against K562 cells in vitro. A mechanistic in silico study showed that hexaprenol, phytol, and 18-[(1-oxohexadecyl) oxy]-9-octadecenoic acid exhibited a strong binding affinity towards topoisomerase (docking score −12.50, −9.19, and −13.29 kcal/mol, respectively), and showed as well a strong binding affinity towards Abl kinase (docking score −11.91, −9.35, and −12.59 kcal/mol, respectively). Molecular dynamics study revealed that 18-[(1-oxohexadecyl) oxy]-9-octadecenoic acid produced stable complexes with both topoisomerase and Abl kinase with RMSD values of 1.81 and 1.85 Å, respectively. As a result of our findings, we recommend more in vivo and preclinical studies to confirm the potential benefit of spinach leaves for chronic myeloid leukemia patients. Graphical Abstract: [Figure not available: see fulltext.
Phytochemical Investigation of Egyptian Riverhemp: A Potential Source of Antileukemic Metabolites
As part of our research group\u27s continuous efforts to find alternative treatments for cancer, the aqueous ethanol extract of Sesbania sesban L. Merr. (SS, Egyptian riverhemp) demonstrated an antileukemic activity against K562 cell line. Bioguided fractionation of SS leaves hydroethanolic extract resulted in the isolation of one new compound (33) named as hederatriol 3-O-β-D-glucuronic acid methyl ester as well as 34 known compounds. Seven compounds ((34), (22), (20), (24), (21), (19), and (35)) showed high antiproliferative effects (IC50 = 22.3, 30.8, 31.3, 33.7, 36.6, 37.5, and 41.5 μM, respectively), while four compounds ((32), (5), (29), and (1)) showed milder activities (IC50 = 56.4, 67.6, 83.3, and 112.3 μM, respectively). A mechanistic study was further carried out on a molecular genetics level against several transcription factors signaling pathways that are incorporated in the incidence of cancer. The results showed that compounds (22) and (21) demonstrated a specific inhibition of Wnt pathway (IC50 = 3.8 and 4.6 μM, respectively), while compound (22) showed a specific inhibition of Smad pathway (IC50 = 3.8 μM). Compound (34) strongly altered the signaling of Smad and E2F pathways (IC50 = 5 μM). The bioactive metabolites were further investigated in silico by docking against several targets related to K562 cell line. The results showed that compounds (22) and (34) exhibited a strong binding affinity towards topoisomerase (docking score = -7.81 and -9.30 Kcal/Mole, respectively). Compounds (22) and (34) demonstrated a strong binding affinity towards EGFR-tyrosine kinase (docking score = -7.12 and -7.35 Kcal/Mole, respectively). Moreover, compound (34) showed a strong binding affinity towards Abl kinase (docking score = -7.05 Kcal/Mole)
CYTOTOXIC AND ANTIOXIDANT ACTIVITIES OF SECONDARY METABOLITES FROM PULICARIA UNDULATA
Objective: To evaluate the in vitro cytotoxicity, antioxidant activities and structure-activity relationship of secondary metabolites isolated from Pulicaria undulata.Methods: The methylene chloride-methanol (1:1) extract of the air-dried aerial parts of Pulicaria undulata was fractionated and separated to obtain the isolated compounds by different chromatographic techniques. Structures of the isolated compounds were determined on the basis of the extensive spectroscopic analysis, including 1D and 2D NMR and compared with the literature data. The crude extract and the isolated compounds were evaluated for in vitro antioxidant activity using the 2,2 diphenyl dipicryl hydrazine (DPPH) method and cytotoxic assay using human breast cancer (MCF-7) and hepatoma (Hep G2) cell line.Results: Nine secondary metabolites were isolated from Pulicaria undulata in this study. Of which two terpenoidal compounds; 8-epi-ivalbin and 11β, 13-dihydro-4H-xanthalongin 4-O-β-D-glucopyranoside firstly isolated from the genus pulicaria and three flavonoids; eupatolitin, 6-methoxykaempferol, and patulitrin firstly isolated from P. undulata. 6-methoxykaempferol (IC50 2.3 µg/ml) showed the most potent antioxidant activity. The highest cytotoxic effect against MCF-7 and Hep G2 cells was obtained with eupatolitin (IC50 27.6 and 23.5 µg/ml) respectively. The structure-activity relationship was also examined and the findings presented here showed that 3, 5, 7, 4' and 3, 5, 4', 5'-hydroxy flavonoids were potent antioxidant and has cytotoxic activity.Conclusion: Pulicaria undulata is a promising medicinal plant, and our study tends to support the therapeutic value of this plant as antioxidant drug and in the treatment of cancer
Improvement of Cell Wall Degrading Enzymes Production by Alginate Encapsulated Trichoderma spp.
Conidia of three Trichoderma isolates were formulated to make alginate pellets with or without 0.5 % chitin or dried fungal mycelium of Fusarium oxysporum as carbon source. The formulations were compared for their ability of in vitro chitinase and β-1,3-glucanase
production with free fungal spore suspensions. Conidia entrapped in alginate with or without adjuvant showed high production of enzymes (especially for chitinase) even when repeated 4 times. The addition of chitin or dried fungal mycelium as adjuvant enhanced the enzyme production up to 5 and 2-fold for chitinase and β-1,3-glucanase, respectively. Alginate concentration and surface area of the beads affected the enzyme production. The optimum initial pH, incubation time and temperature were pH=6, 12 days and 40 °C for chitinase, and pH=7, 10 days and 35 °C for β-1,3-glucanase production. The improvement of cell wall degrading enzyme production by alginate encapsulated Trichoderma could explain the in vivo inhibitory effect of such formulations on the target phytopathogenic fungi
<i>Garcinia cambogia</i> phenolics as potent anti-COVID-19 agents:phytochemical profiling, biological activities, and molecular docking
COVID-19 is a disease caused by the coronavirus SARS-CoV-2 and became a pandemic in a critically short time. Phenolic secondary metabolites attracted much attention from the pharmaceutical industries for their easily accessible natural sources and proven antiviral activity. In our mission, a metabolomics study of the Garcinia cambogia Roxb. fruit rind was performed using LC-HRESIMS to investigate its chemical profile, especially the polar aspects, followed by a detailed phytochemical analysis, which led to the isolation of eight known compounds. Using spectrometric techniques, the isolated compounds were identified as quercetin, amentoflavone, vitexin, rutin, naringin, catechin, p-coumaric, and gallic acids. The antiviral activities of the isolated compounds were investigated using two assays; the 3CL-Mpro enzyme showed that naringin had a potent effect with IC50 16.62 μg/mL, followed by catechin and gallic acid (IC50 26.2, 30.35 μg/mL, respectively), while the direct antiviral inhibition effect of naringin confirmed the potency with an EC50 of 0.0169 μM. To show the molecular interaction, in situ molecular docking was carried out using a COVID-19 protease enzyme. Both biological effects and docking studies showed the hydrophobic interactions with Gln 189 or Glu 166, per the predicated binding pose of the isolated naringin
Increased prevalence of sleep disturbances and daytime sleepiness in subjects with bronchial asthma: a population study of young adults in three European countries
To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldThe aim of this study was to investigate whether asthma is associated with decreased quality of sleep and increased daytime sleepiness. The study involved a random population of 2,202 subjects supplemented by 459 subjects with suspected asthma, aged 20-45 yrs. The subjects were from Reykjavik (Iceland), Uppsala and Göteborg (Sweden) and Antwerp (Belgium), and participated in the European Community Respiratory Health Survey. The investigation included a structured interview, methacholine challenge, skinprick tests and a questionnaire on sleep disturbances. Participants in Iceland and Sweden also estimated their sleep times and made peak expiratory flow (PEF) recordings during a period of 1 week. Asthma was defined as self-reported physician-diagnosed asthma with current asthma-related symptoms (n = 267). Difficulties inducing sleep (DIS) and early morning awakenings (EMA) were about twice as common, and daytime sleepiness 50% more common, in asthmatics compared with subjects without asthma. After adjusting for possible confounders, a positive association was found between asthma and: DIS (odds ratio (OR) = 1.8); EMA (OR = 2.0); daytime sleepiness (OR = 1.6); snoring (OR = 1.7); and self reported apnoeas (OR = 3.7). Allergic rhinitis, which was reported by 71% of subjects with asthma, was independently related to DIS (OR = 2.0) and daytime sleepiness (OR = 1.3). A significant correlation was found between the number of asthma-related symptoms and sleep disturbances (p < 0.001). Asthma is associated with decreased subjective quality of sleep and increased daytime sleepiness. Concurrent allergic rhinitis may be an important underlying cause of sleep impairment in asthmatic patients
Effect of Benomyl on Chitinase and β-1,3-Glucanase Production by Free and Alginate Encapsulated Trichoderma harzianum
On PDA-benomyl plates growth of Trichoderma harzianum was inhibited by 20 and 30 % at benomyl 1 and 2 μg/mL, respectively, and was completely inhibited at 5 μg/mL. In minimal synthetic medium (MSM) amended with different concentrations of benomyl (1.0, 3.0, 5.0, 7.0 and 10.0 μg/mL), fungal immobilisation improved chitinase and β-1,3-glucanase production at low benomyl concentrations (1, 3 and 5 μg/mL). Further increase in the production of both enzymes was obtained by immobilisation at higher benomyl concentrations (7 and 10 μg/mL). Fungal immobilisation increased bound chitinase by 15- to 30-fold at 3 and 5 μg/mL benomyl concentration, respectively. However, no effect was obtained on the bound β-1,3-glucanase. Different benomyl concentrations (0.3 to 1500 μg/mL) had no significant inhibitory effect on the activities of free or immobilised chitinase and β-1,3-glucanase. It could be suggested that either immobilised Trichoderma or immobilised chitinase and β-1,3-glucanase could be used in combination with benomyl to control plant pathogens
Associations between the Bacterial Composition of Farm Bulk Milk and the Microbiota in the Resulting Swedish Long-Ripened Cheese
The maturation of a traditional Swedish long-ripened cheese has shown increasing variation in recent years and the ripening time is now generally longer than in the past. While the cheese is reliant on non-starter lactic acid bacteria for the development of its characteristic flavour, we hypothesised that the observed changes could be due to variations in the microbiota composition and number of bacteria in the raw milk used for production of the cheese. To evaluate associations between microbiota in the raw milk and the resulting cheese, three clusters of commercial farms were created to increase variation in the microbiota of dairy silo milk used for cheese production. Cheese production was performed in three periods over one year. Within each period, milk from the three farm clusters was collected separately and transported to the cheese production facility. Following pasteurisation, the milk was processed into the granular-eyed cheese and matured at a dedicated cheese-ripening facility. For each cheese batch, farm bulk and dairy silo milk samples, a starter culture, early process samples and cheese samples from different stages of maturation (7-20 months) were collected and their microbiota characterised using 16S rRNA amplicon sequencing. The microbiota in the farm bulk milk differed significantly between periods and clusters. Differences in microbiota in dairy silo milk were observed between periods, but not between farm clusters, while the cheese microbiota differed between periods and clusters. The top 13 amplicon sequence variants were dominant in early process samples and the resulting cheese, making up at least 93.3% of the relative abundance (RA). Lactococcus was the dominant genus in the early process samples and, together with Leuconostoc, also dominated in the cheese samples. Contradicting expectations, the RA of the aroma-producing genus Lactobacillus was low in cheese during ripening and there was an unexpected dominance of starter lactic acid bacteria even at the later stages of cheese ripening. To identify factors behind the recent variations in ripening time of this cheese, future studies should address the effects of process variables and the dairy environment
Milking system and premilking routines have strong effect on the microbial community in bulk tank milk
In this study, we investigated the variation in the microbial community present in bulk tank milk samples and the potential effect of different farm management factors. Bulk tank milk samples were collected repeatedly over one year from 42 farms located in northern Sweden. Total and thermoresistant bacteria counts and 16S rRNA gene-based amplicon sequencing were used to characterize microbial community composition. The microbial community was in general heterogeneous both within and between different farms and the community composition in the bulk tank milk was commonly dominated by Pseudomonas, Acinetobacter, Streptococcus, unclassified Peptostreptococcaceae, and Staphylococcus. Principal component analysis including farm factor variables and microbial taxa data revealed that the microbial community in milk was affected by type of milking system. Milk from farms using an automatic (robot) milking system (AMS) and loose housing showed different microbial community composition compared with milk from tiestall farms. A discriminant analysis model revealed that this difference was dependent on several microbial taxa. Among farms using an automatic milking system, there were further differences in the microbial community composition depending on the brand of the milking robot used. On tiestall farms, routines for teat preparation and cleaning of the milking equipment affected the microbial community composition in milk. Total bacteria count (TBC) in milk differed between the farm types, and TBC were higher on AMS than tiestall farms (log 4.05 vs. log 3.79 TBC/mL for AMS and tiestalls, respectively). Among tiestall farms, milk from farms using a chemical agent in connection to teat preparation and a more frequent use of acid to clean the milking equipment had lower TBC in milk, than milk from farms using water for teat preparation and a less frequent use of acid to clean the milking equipment (log 3.68 vs. 4.02 TBC/mL). There were no significant differences in the number of thermoresistant bacteria between farm types. The evaluated factors explained only a small proportion of total variation in the microbiota data, however, despite this, the study highlights the effect of routines associated with teat preparation and cleaning of the milking equipment on raw milk microbiota, irrespective of type of milking system used
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