Diversity and Biological Activities of Endophytic Fungi from the Flowers of the Medicinal Plant Vernonia anthelmintica.

Secondary metabolites produced by endophytic fungi are an important source of biologically active compounds. The current research was focused on the biological activities of ethyl acetate extracts of fungi, isolated and identified from Vernonia anthelmintica flowers for the first time. In addition, an investigation of the non-polar chemical composition of dichloromethane-ethyl acetate extracts of the most active fungal strain was carried out. The isolates included Ovatospora senegalensis NR-03, Chaetomium globosum NR-04, Thielavia subthermophila NR-06, Aspergillus calidoustus NR-10, Aspergillus keveii XJF-23 and Aspergillus terreus XJF-3 species. Strains were identified by 18S rRNA gene sequencing methods and were registered in GenBank. Crude extracts of the fungi displayed in vitro biological activities, including antimicrobial and cytotoxic activities. A melanin content assay was performed on murine B16 cells. An ethyl acetate extract of O. senegalensis NR-03 showed high anticancer and antimicrobial activity; therefore, we also studied the non-polar chemical composition of the dichloromethane-ethyl acetate fraction and identified 52 non-polar compounds with the different medium. This investigation discovered that the secondary metabolites of the total extract of endophytic fungi could be a potential source of alternative natural antimicrobial, cytotoxic and melanin synthesis activity in their host plant, and the isolation of bioactive metabolites may provide a lead to new compounds of pharmaceutical significance.

Endophytic Bacteria Associated with Medicinal Plant Vernonia anthelmintica: Diversity and Characterization.

Increasing evidence shows that endophytic bacteria living inside plant tissue may possess similar biological activity and produce similar metabolites to their hosts. This study aimed to determine the diversity of endophytic bacteria associated with Vernonia anthelmintica and to evaluate their biological activity. The bacteria were isolated from the plant tissue using culture-dependent techniques. Comparison of the 16S rRNA gene sequences of endophytic bacteria isolated from V. anthelmintica showed that isolates belong to the species Micrococcus endophyticus VERA1, Bacillus megaterium VERA2, Pseudomonas chlororaphis VERA3, P. kilonensis VERA4, Stenotrophomonas pavanii VERA5, B. endophyticus VERA6, S. maltophilia VERA7, Pantoea ananatis VERA8, B. atrophaeus VERA9 and M. flavus VERA10. Activity studies showed that the endophytic bacteria share several similar biological properties with their host plant including antimicrobial, anti-vitiligo and antidiabetic activities. These findings indicate that plant phytochemical compounds and activity play an important role in the physiological properties of their endophytes.

Modification of natural compounds through biotransformation process by microorganisms and their pharmacological properties.

The biotransformation of natural compounds by fungal microorganisms is a complex biochemical process. Tandem whole-cell biotransformation offers a promising, alternative, and cost-effective method for modifying of bioactive novel compounds. This approach is particularly beneficial for structurally complex natural products that are difficult to be synthesized through traditional synthetic methods. Biotransformation also provides significant regio- and stereoselectivity, making it a valuable tool for the chemical modification of natural compounds. By utilizing microbial conversion reactions, the biological activity and structural diversity of natural products can be enhanced. In this review, we have summarized 282 novel metabolites resulting from microbial transformation by various microorganisms. We discussed the chemical structures and pharmacological properties of these novel biotransformation products. The review would assist scientists working in the fields of biotechnology, organic chemistry, medicinal chemistry, and pharmacology.

Secondary metabolites produced by endophytic Pantoea ananatis derived from roots of Baccharoides anthelmintica and their effect on melanin synthesis in murine B16 cells.

Five indole derivatives, 1H-indol-7-ol (1), tryptophol (2), 3-indolepropionic acid (3), tryptophan (4), 3,3-di(1H-indol-3-yl)propane-1,2-diol (5) and two diketopiperazines, cyclo(L-Pro-L-Tyr) (6), cyclo[L-(4-hydroxyprolinyl)-L-leucine (7) along with one dihydrocinnamic acid (8) were isolated from Pantoea ananatis VERA8, that endophytic bacteria derived from Baccharoides anthelmintica roots. This is a first report towards an isolation of endophytic strains (funji or bacteria) from the B. anthelmintica herb. The synergetic properties of the total extract compositions, as well as effects of the pure isolated secondary metabolites evaluated on their melanin synthesis in murine B16 cells towards for vitiligo treatment.

Synthesis and Characterization of Novel Chickpea Protein Hydrolysate-Vanadium Complexes Having Cell Inhibitory Effects on Lung Cancer A549 Cells Lines.

Designing new types of drugs with preferred properties against cancer is a great issue for scientists dealing with synthesis and study of biological activity. Several organometallic compounds used in chemotherapy reveal side effects. Peptides from edible sources having no side effects may play a transport role in the delivery of anticancer metal ions into targeted tumor cells. For the last two decades, peptide-metal complexes have been considered as potential anticancer agents. In this work, oxovanadium complexes of peptides from Chickpea (Cicer arietinum L.) seeds' protein hydrolysate were investigated. The albumin fraction of Chickpea seeds protein was hydrolyzed with a combination of enzymes papain, trypsin, and alcalase. The hydrolysate was combined with vanadyl ions and obtained oxovanadium complexes were studied by FTIR, SEM-EDX, and TG-DSC analyses, and cell inhibition activity against A549 cells was detected by MTT Assay. In a result, activity of the complexes (IC50 = 14.39 µg/mL) increased 1.7-fold compared to the activity of inorganic salt of vanadium (IC50 = 24.75 µg/mL) against A549 cells. The complexes (CPH-V) were fractionated through Sephadex G-15, and the second active fraction, named CPH-V G15-II was studied by nano-Q-TOF LC/MS. Nine peptides with a molecular mass range of 437-1864 Da were identified. Seven of them were theoretically considered as cell-penetrating peptides. These results could serve first steps for deeper fundamental research on food-derived peptide-vanadium complexes.

Biological Activity of Endophytic Fungi from the Roots of the Medicinal Plant Vernonia anthelmintica.

Endophytic fungi were first isolated from the fresh root of the Chinese medicinal plant Vernonia anthelmintica collected from the Hotan Prefecture within the Xinjiang Autonomous region of the People's Republic of China. This plant has been used in Uyghur traditional medicine to treat vitiligo, a skin condition characterized by patches of the skin losing their pigment. In total, fifteen fungal strains were isolated. Among these, four endophytic fungi were identified by their DNA sequences and registered to GenBank with accession numbers. The isolates were identified as Schizophyllum commune XJA1, Talaromyces sp. XJA4, Aspergillus sp. XJA6, Aspergillus terreus XJA8. Ethyl acetate extracts of all fungal strains were used to quantify melanin content and to identify in vitro biological activity assays including antimicrobial, antioxidant, cytotoxic, antidiabetic and tyrosinase activity on B16 cells. Among the extracts of all four identified strains, the ethyl acetate extract of the Aspergillus sp. XJA6 was chosen for further characterization because it presented the highest biological activity against these tests. In addition, twenty four volatile compounds from the petroleum ether fraction were characterized by GC-MS.

Optimization of ultrasonic-assisted extraction, characterization and biological activities of polysaccharides from Orchis chusua D. Don (Salep).

In the present study, ultrasonic-assisted extraction (UAE) of polysaccharides from Orchis chusua D. Don (salep) was optimized by response surface methodology (RSM) combined with a Box-Behnken design (BBD), the optimum conditions were determined to be: ultrasonic power of 390 W, extraction temperature of 60 °C, extraction time of 50 min and water/raw material ratio of 40 mL/g. Based on it, 48.30 ±â€¯0.6% yield of crude polysaccharide was obtained. After purification, the chemical compositions, physicochemical and structural property was investigated based on the GC-MS, TGA, XRD, SEM and Congo red test. The results showed that USP-U and USP-N were hetero-polysaccharides, mainly composed of mannose and glucose, and the average molecular weight was 25.57 kDa and 11.64 kDa, respectively. FT-IR spectra and NMR results indicated that the presence of α-linkage glycopyranose via typical peaks. Furthermore, reducing power and antioxidant activities of both purified fractions showed a relatively high ability to scavenge free radicals. Lastly, the cytotoxicity assay showed that purified polysaccharides have no obvious cytotoxicity against RAW267.4 and L6 cells at their effective concentration and had potent anti-inflammatory activity in a concentration-dependent manner. Salep polysaccharide is expected to be developed as a new efficacy factor in the pharmaceutical and food industry.

Synthesis of silver nanoparticles on the basis of low and high molar mass exopolysaccharides of Bradyrhizobium japonicum 36 and its antimicrobial activity against some pathogens.

Silver nanoparticles (SNPs) were synthesized on the basis of exopolysaccharides (low and high molar mass) of diazotrophic Bradyrhizobium japonicum 36 strain. The synthesis of SNPs was carried out by direct reduction of silver nitrate with ethanol-insoluble (high molar mass, HMW) and ethanol-soluble (low molar mass, LMW) fractions of exopolysaccharides (EPS), produced by diazotrophic strain B. japonicum 36. SNPs were characterized using UV-vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). SNPs synthesized on the basis of LMW EPS absorbed radiation in the visible regions of 420 nm, whereas SNPs based on the HMW EPS have a wavelength maximum at 450 nm because of the strong SPR transition. Moreover, the antibacterial and antifungal activities of the SNPs were examined in vitro against Escherichia coli, Staphylococcus aureus, and Candida albicans. SNPs synthesized on the basis of LMW EPS were active than those synthesized on the basis of HMW EPS. Besides, UV-visible spectroscopic evaluation confirmed that SNPs synthesized on the basis of LMW EPS were far more stable than those obtained on the basis of HMW EPS.