• Parasites, Hosts and Diseases
• /
• v.61 no.4
• /
• pp.405-417
• /
• 2023

Chagas disease, caused by Trypanosoma cruzi parasite, is a significant but neglected tropical public health issue in Latin America due to the diversity of its genotypes and pathogenic profiles. This complexity is compounded by the adverse effects of current treatments, underscoring the need for new therapeutic options that employ medicinal plant extracts without negative side effects. Our research aimed to evaluate the trypanocidal activity of Bidens pilosa fractions against epimastigote and trypomastigote stages of T. cruzi, specifically targeting the Brener and Nuevo León strains-the latter isolated from Triatoma gerstaeckeri in General Terán, Nuevo León, México. We processed the plant's aerial parts (stems, leaves, and flowers) to obtain a methanolic extract (Bp-mOH) and fractions with varying solvent polarities. These preparations inhibited more than 90% of growth at concentrations as low as 800 ㎍/ml for both parasite stages. The median lethal concentration (LC₅₀) values for the Bp-mOH extract and its fractions were below 500 ㎍/ml. Tests for cytotoxicity using Artemia salina and Vero cells and hemolytic activity assays for the extract and its fractions yielded negative results. The methanol fraction (BPFC3MOH1) exhibited superior inhibitory activity. Its functional groups, identified as phenols, enols, alkaloids, carbohydrates, and proteins, include compounds such as 2-hydroxy-3-methylbenzaldehyde (50.9%), pentadecyl prop-2-enoate (22.1%), and linalool (15.4%). Eight compounds were identified, with a match confirmed by the National Institute of Standards and Technology (NIST-MS) software through mass spectrometry analysis.

• Journal of Microbiology and Biotechnology
• /
• v.33 no.11
• /
• pp.1437-1447
• /
• 2023

A recently bioinformatic analysis of genomic sequences of fungi indicated that fungi are able to produce more secondary metabolites than expected. Despite their potency, many biosynthetic pathways are silent in the absence of specific culture conditions or chemical cues. To access cryptic metabolism, 108 fungal strains isolated from various sites were cultured with or without Streptomyces sp. 13F051 which mainly produces trichostatin analogues, followed by comparison of metabolic profiles using LC-MS. Among the 108 fungal strains, 14 produced secondary metabolites that were not recognized or were scarcely produced in mono-cultivation. Of these two fungal strains, Myrmecridium schulzeri 15F098 and Scleroconidioma sphagnicola 15S058 produced four new compounds (1-4) along with a known compound (5), demonstrating that all four compounds were produced by physical interaction with Streptomyces sp. 13F051. Bioactivity evaluation indicated that compounds 3-5 impede migration of MDA-MB-231 breast cancer cells.

• FOCUS: LIFE SCIENCE
• /
• no.1
• /
• pp.3.1-3.7
• /
• 2024

The article discusses the critical role of chromatography in the analysis and purification of proteins in biopharmaceuticals, emphasizing the importance of comprehensive characterization for ensuring their safety and efficacy. It highlights the use of Avantor® ACE® HPLC columns for the separation and purification of proteins, focusing on the analysis of intact proteins using reversed-phase liquid chromatography (RPLC) with fully porous particles. This article also details the application of different mobile phase additives, such as TFA and formic acid, and emphasizes the advantages of using type B ultra-pure silica-based columns for efficiency and peak shape in biomolecule analysis. Additionally, it addresses the challenges of analyzing intact proteins due to slow molecular diffusion and introduces the concept of solid-core (or superficially porous) particles, emphasizing their benefits over traditional porous particles for the analysis of therapeutic proteins. Furthermore, it discusses the development of Avantor® ACE® UltraCore BIO columns, specifically designed for the high-efficiency separation of large biomolecules, such as proteins, and demonstrates their effectiveness in achieving high-resolution separations, even for higher molecular weight proteins like monoclonal antibodies (mAbs). In addition, it underscores the complexity of analyzing and characterizing intact protein biopharmaceuticals, requiring a range of analytical techniques and the use of wide-pore stationary phases, operated at elevated temperatures and with relatively shallow gradients. It highlights the comprehensive range of options offered by Avantor® ACE® wide pore columns, including both fully porous and solid-core particles, bonded with a variety of complementary stationary phase chemistries to optimize selectivity during method development. The use of ultrapure and highly inert base silica is emphasized for enabling the use of lower concentrations of mobile phase modifiers without compromising analyte peak shape, particularly beneficial for LC-MS applications. Then the article concludes by emphasizing the significance of reversed-phase liquid chromatography and its compatibility with mass spectrometry as a valuable tool for the separation and analysis of intact proteins and their closely related variants in biopharmaceuticals.

• Journal of Microbiology and Biotechnology
• /
• v.34 no.7
• /
• pp.1452-1463
• /
• 2024

Fungi generate different metabolites some of which are intrinsically bioactive and could therefore serve as templates for drug development. In the current study, six endophytic fungi namely Aspergillus flavus, Aspergillus tubigenesis, Aspergillus oryzae, Penicillium oxalicum, Aspergillus niger, and Aspergillus brasiliensis were isolated and identified from the medicinal plant, Silybum marianum. These endophytic fungi were identified through intra transcribed sequence (ITS) gene sequencing. The bioactive potentials of fungal extracts were investigated using several bioassays such as antibacterial activity by well-diffusion, MIC, MBC, anti-biofilm, antioxidant, and haemolysis. The Pseudomonas aeruginosa PAO1 was used to determine the antibiofilm activity. The ethyl acetate extract of Aspergillus flavus showed strong to moderate efficacy against Staphylococcus aureus, Escherichia coli, P. aeruginosa, and Bacillus spizizenii. Aspergillus flavus and Aspergillus brasiliensis exhibited significant antibiofilm activity with IC₅₀ at 4.02 and 3.63 mg/ml, while A. flavus exhibited maximum antioxidant activity of 50.8%. Based on HPLC, LC-MS, and NMR experiments kojic acid (1) and carbamic acid (methylene-4, 1-phenylene) bis-dimethyl ester (2) were identified from A. flavus. Kojic acid exhibited DPPH free radical scavenging activity with an IC₅₀ value of 99.3 ㎍/ml and moderate activity against ovarian teratocarcinoma (CH1), colon carcinoma (SW480), and non-small cell lung cancer (A549) cell lines. These findings suggest that endophytic fungi are able to produce promising bioactive compounds which deserve further investigation.

• Journal of Microbiology and Biotechnology
• /
• v.34 no.9
• /
• pp.1836-1847
• /
• 2024

Polyethylene terephthalate (PET), one of the most widely used plastics in the world, causes serious environmental problems. Recently, scientists have been focused on the enzymatic degradation of PET, an environmentally friendly method that offers an attractive approach to the degradation and recycling of PET. In this work, PET hydrolase from Streptomyces sp. W2061 was biochemically characterized, and the biodegradation of PET was performed using the PET model substrate bis (2-hydroxyethyl terephthalate) (BHET). PET hydrolase has an isoelectric point of 5.84, and a molecular mass of about 50.31 kDa. The optimum pH and temperature were 7.0 and 40℃, respectively. LC-MS analysis of the enzymatic products showed that the PET hydrolase successfully degraded a single ester bond of BHET, leading to the formation of MHET. Furthermore, in silico characterization of the PET hydrolase protein sequence and its predicted three-dimensional structure was designed and compared with the well-characterized IsPETase from Ideonella sakaiensis. The structural analysis showed that the (Gly-x1-Ser-x2-Gly) serine hydrolase motif and the catalytic triad (Ser, Asp, and His) were conserved in all sequences. In addition, we integrated molecular dynamics (MD) simulations to analyze the variation in the structural stability of the PET hydrolase in the absence and presence of BHET. These simulations showed the formation of a stable complex between the PET hydrolase and BHET. To the best of our knowledge, this is the first study on Streptomyces sp. W2061 to investigate the BHET degradation activity of PET hydrolase, which has potential application in the biodegradation of plastics in the environment.

• Applied Chemistry for Engineering
• /
• v.28 no.4
• /
• pp.479-484
• /
• 2017

In this study, antioxidative activities and cellular protective effects of 70% ethanol extracts and fractions from lavender were evaluated. The scavenging activity ($FSC_{50}$) of free radical (1,1-phenyl-2-picrylhydrazyl, DPPH) was 46.6, 45.5 and $477.5{\mu}g/mL$ in the 70% ethanol extract, ethyl acetate fraction and aglycone fraction, respectively. The reactive oxygen species scavenging activities (${OSC_{50}$) of 70% ethanol extract, ethyl acetate fraction and aglycone fraction were 8.1, 3.3 and $17.6{\mu}g/mL$, respectively, and they showed lower antioxidative activity than that of using L-ascorbic acid ($1.5{\mu}g/mL$). However, the aglycone fraction showed higher photohemolysis protective effect than that of using the 70% ethanol extract and ethyl acetate fraction. At $50{\mu}M$ concentration, the cellular protective effect (${\tau}_{50}$) of 70% ethanol extract, ethyl acetate fraction and aglycone fraction from lavender was 70.6, 87.2 and 165.2 min, respectively. In particular, the lavender aglycone fraction showed 3.8 times higher cellular protective effect than that of (+)-${\alpha}$-tocopherol. The lavender fractional components including luteolin 7-O-glucuronide, vitextin, rosmarinic acid, luteolin, and apigenin were identified using TLC and LC-MS. However, the lavender aglycone fraction did not show any significant increase in flavonoids (luteolin and apigenin) compared to that of the ethyl acetate fraction. In conclusion, it is suggested that lavender may be applied as an antioxidant material in cosmetic industries.

• Journal of Applied Biological Chemistry
• /
• v.61 no.1
• /
• pp.83-91
• /
• 2018

Advances in bacterial and fungal genome mining uncover a plethora of cryptic secondary metabolite biosynthetic gene clusters. Guided by the genome information, targeted transcriptional derepression could be employed to determine the product of a cryptic gene cluster and to explore its biological role. Monascus spp. are food grade filamentous fungi popular in eastern Asia and several genome data belong to them are now available. We achieved transcription activation of a cryptic fungal polyketide synthase-nonribosomal peptide synthase gene Mpfus1 in Monascus purpureus ${\Delta}MpPKS5$ by inserting Aspergillus gpdA promoter at the upstream of Mpfus1 through double crossover gene replacement. The gene cluster with Mpfus1 show a high similarity to those for the biosynthesis of conjugated polyene derivatives with 2-pyrrolidone ring and the mycotoxin fusarin is the representative member of this group. The ${\Delta}MpPKS5$ is incapable of producing azaphilone pigment, providing an excellent background to identify chromogenic and UV-absorbing compounds. Activation of Mpfus1 resulted in a yellow hue on mycelia and its methanol extract exhibit a maximum absorption at 365 nm. HPLC analysis of the organic extracts indicated the presence of a variety of yellow compounds in the extract. This implies that the product of MpFus1 is metabolically or chemically unstable. LC-MS analysis guided us to predict the MpFus1 product and to propose that the Mpfus1-containing gene cluster encode the biosynthesis of a desmethyl analogue of fusarin. This study showcases the genome mining in Monascus and the possibility to unveil new biological activities embedded in it.

• Applied Chemistry for Engineering
• /
• v.29 no.2
• /
• pp.176-184
• /
• 2018

In the present study, we investigated the antioxidative properties, cellular protective effects and component analyses of 50% ethanol extract, ethyl acetate fraction and aglycone fraction obtained from Lysimachia christinae Hance (L. christinae Hance). In the evaluation of antioxidative properties, the free radical scavenging activities ($FSC_{50}$) of 50% ethanol extract, ethyl acetate fraction and aglycone fraction were 146.8, 22.2 and $27.2{\mu}g/mL$, respectively and total antioxidant capacities ($OSC_{50}$) were 29.3, 2.9 and $4.5{\mu}g/mL$, respectively. The ethyl acetate fraction showed the highest free radical scavenging activity and total antioxidant capacity. Also, the cellular protective effects (${\tau}_{50}$) of 50% ethanol extract, ethyl acetate fraction and aglycone fraction on $^1O_2$ induced photohemolysis of human erythrocytes were 26.9, 57.5 and 103.9 min at $5{\mu}g/mL$, respectively. In particular, ${\tau}_{50}$ of the aglycone fraction exhibited a higher cellular protective effect than that of (+)-${\alpha}$-tocopherol (37.7 min). The cell viability of the ethyl acetate fraction on the UVB-induced cell damage increased up to 90.1%. In addition, the ethyl acetate fraction ($5-25{\mu}g/mL$) showed cellular protective effects on the $H_2O_2-induced$ cell damages in a dose-dependent manner. TLC, HPLC, UV-vis spectroscopy and LC-MS were used to analyse components of the ethyl acetate fraction and the main components were quercetin, kaempferol and their glycosides. In conclusion, L. christinae Hance extract/fraction can function as antioxidants to protect the skin exposed to UV radiation and may also be used as a novel functional cosmetic material, for example, an antioxidant against skin photoaging.

• Journal of Veterinary Clinics
• /
• v.29 no.3
• /
• pp.233-236
• /
• 2012

Cefquinome, a fourth generation cephalosporin, has been solely used for veterinary medicine and has a broad antibacterial spectrum against gram-negatives and gram-positives being very stable to ${\beta}$-lactamases. This study was conducted to evaluate the bioequivalence of two cefquinome 2.5% products in piglets. Plasma cefquinome concentrations were analyzed by liquid chromatography-mass spectrometry (LC/MS). Mean maximum concentration ($C_{max}$) of test product ($Cequus^{(R)}$) and reference product ($Cobactan^{(R)}$) were $4.34{\pm}0.58$ and $4.22{\pm}0.47{\mu}g/mL$, and mean area under the concentration time curve ($AUC_{0{\rightarrow}{\infty}}$) values were $10.43{\pm}1.96$ and $10.25{\pm}2.98{\mu}g{\cdot}h/mL$, respectively. The 90% confidence intervals for the ratio of $C_{max}$ (0.941-1.115), and $AUC_{0{\rightarrow}{\infty}}$ (0.927-1.172) values for the test and reference products were within the acceptable bioequivalence limit of 0.80-1.25. It is concluded that two commercial cefquinome injectable solutions are bioequivalent in their extent of drug absorption in piglets.

• Food Science of Animal Resources
• /
• v.26 no.4
• /
• pp.418-425
• /
• 2006

This study was conducted to evaluate extraction properties of crude saponin and ginsenosides, and their effects on sensory properties of emulsified pork sausage. Non-dried ginseng root was boiled in 0 (e.g., 100% distilled water), 20, 40, 60, 80 or 100% ethanol, and powdered by a freezing dry method. Weight of dried powder for the 0% ethanol extraction was 20% of initial non-dried ginseng weight, while $20{\sim}80%$ and 100% ethanol extractions resulted in approximately 15 and 10% of their initial weights, respectively. On the other hand, crude saponin content in the dried powder was linearly increased for a higher ethanol content where 100% ethanol extraction resulted in 123.52 mg/g. LC/MS analysis of crude saponin for quantifying ginsenosides showed that Rb1, Rb2 and Rc were significantly (p<0.05) higher levels for both 80 and 100% ethanol extractions. In the case of Rg1 ginsenoside, 60, 80 and 100% ethanol extractions resulted in significantly (p<0.05) higher levels. Emulsified pork sausages containing 0, 1 or 2% ginseng extracts were smoked or non-smoked and their sensory characteristics and preference were evaluated. Smoking process significantly (p<0.05) decreased juiciness and tenderness, but the treatment significantly (p<0.05) improved flavor and consumer preference. It was particularly noticed that a 2% addition of ginseng extract prevented the adverse effects of smoking process on juiciness and tenderness while the 2% addition significantly (p<0.05) improved consumer preference. The current results implied that addition of ginseng extract in emulsified pork sausage could improve sensory quality.