Make more knowledge even in less time every day. You may not always spend your time and money to go abroad and get the experience and knowledge by yourself. Reading is a good alternative to do in getting this desirable knowledge and experience. You may gain many things from experiencing directly, but of course it will spend much money. So here, by reading a textbook of oral pathology, you can take more advantages with limited budget.

A textbook of oral pathology: William G. Shafer, D.D.S., Maynard K. Hine, D.D.S., Barnet M. Levy, D.D.S., and Charles E. Tomich, D.D.S., ed. 4, Philadelphia, 1983, W. B. Saunders Co. 917 pages. $36.50

Naringenin is a flavonoid belonging to flavanones subclass. It is widely distributed in several Citrus fruits, bergamot, tomatoes and other fruits, being also found in its glycosides form (mainly naringin). Several biological activities have been ascribed to this phytochemical, among them antioxidant, antitumor, antiviral, antibacterial, anti-inflammatory, antiadipogenic and cardioprotective effects. Nonetheless, most of the data reported have been obtained from in vitro or in vivo studies. Although some clinical studies have also been performed, the main focus is on naringenin bioavailability and cardioprotective action. In addition, these studies were done in compromised patients (i.e., hypercholesterolemic and overweight), with a dosage ranging between 600 and 800 μM/day, whereas the effect on healthy volunteers is still debatable. In fact, naringenin ability to improve endothelial function has been well-established. Indeed, the currently available data are very promising, but further research on pharmacokinetic and pharmacodynamic aspects is encouraged to improve both available production and delivery methods and to achieve feasible naringenin-based clinical formulations.

The Therapeutic Potential of Naringenin: A Review of Clinical Trials.

Flavonoids are phytochemical compounds present in many plants, fruits, vegetables, and leaves, with potential applications in medicinal chemistry. Flavonoids possess a number of medicinal benefits, including anticancer, antioxidant, anti-inflammatory, and antiviral properties. They also have neuroprotective and cardio-protective effects. These biological activities depend upon the type of flavonoid, its (possible) mode of action, and its bioavailability. These cost-effective medicinal components have significant biological activities, and their effectiveness has been proved for a variety of diseases. The most recent work is focused on their isolation, synthesis of their analogs, and their effects on human health using a variety of techniques and animal models. Thousands of flavonoids have been successfully isolated, and this number increases steadily. We have therefore made an effort to summarize the isolated flavonoids with useful activities in order to gain a better understanding of their effects on human health.

https://www.mdpi.com/1420-3049/25/22/5243/pdf

Important Flavonoids and Their Role as a Therapeutic Agent.

Effects of the wine polyphenolics quercetin and resveratrol on pro-inflammatory cytokine expression in RAW 264.7 macrophages - Ten years after

Flavonoid biosynthetic pathways in plants: Versatile targets for metabolic engineering.

Characterization of regioselective flavonoid O-methyltransferase from the Streptomyces sp. KCTC 0041BP.

Methylation is a common post-modification reaction that is observed during the biosynthesis of secondary metabolites produced by plants and microorganisms. Based on the sequence information from Streptomyces peucetius ATCC27952, a putative O-methyltransferase (OMT) gene SpOMT7740 was polymerase chain reaction amplified and cloned into E. coli BL21 (DE3) host to test the substrate promiscuity and conduct functional characterization. In vitro and in vivo reaction assays were carried out over various classes of substrates: flavonoids (flavonol, flavones, and isoflavonoid), chalcones, anthraquinones, anthracyclines, and sterol molecules, and the applications in synthesizing diverse classes of O-methoxy natural products were also illustrated. SpOMT7740 catalyzed the O-methylation reaction to form various natural and non-natural O-methoxides, includes 7-hydroxy-8-O-methoxy flavone, 3-O-methoxy flavone, three mono-, di-, and tri-O-methoxy genistein, mono-O-methoxy phloretin, mono-O-methoxy luteolin, 3-O-methoxy β-sitosterol, and O-methoxy anthraquinones (emodin and aloe emodin) and O-methoxy anthracycline (daunorubicin) exhibiting diverse substrate flexibility. Daunorubicin is a native secondary metabolite of S. peucetius. Among the compounds tested, 7,8-dihydroxyflavone was the best substrate for bioconversion to 7-hydroxy-8-O-methoxy flavone, and it was structurally elucidated. This enzyme showed a flexible catalysis over the given ranges of temperature, pH, and divalent cationic conditions for O-methylation.

Substrate Scope of O-Methyltransferase from Streptomyces peucetius for Biosynthesis of Diverse Natural Products Methoxides

Mupirocin is a commercially available antibiotic that acts on bacterial isoleucyl-tRNA synthetase, thereby inhibiting protein synthesis and preventing bacterial infection. An in vitro glycosylation approach was applied to synthesize glycoside derivatives of mupirocin using different NDP-sugars and glycosyltransferase from Bacillus licheniformis. Ultra pressure liquid chromatography-photo diode array analyses of the reaction mixtures revealed the generation of product peak(s). The results were further supported by high-resolution quadruple time of flight electrospray ionization mass spectrometry analyses. The product purified from the reaction mixture with UDP-D-glucose was subjected to NMR analysis, and the structure was determined to be mupirocin 6-O-β-D-glucoside. Other glycoside analogs of mupirocin were determined based on high-resolution mass analyses. Antibacterial activity assays against Staphylococcus aureus demonstrated complete loss of antibacterial activity after glucosylation of mupirocin at the 6-hydroxyl position.

Enzymatic glycosylation of the topical antibiotic mupirocin

Regiospecific biosynthesis of tamarixetin derivatives in Escherichia coli

Genistein is the principal isoflavone constituent of soybean. It has attracted more attention than other plant polyphenols because of its significant affinity with medical interests. Herein, we biosynthesized and structurally characterized ten different natural and non-natural analogues of genistein glycopyranosides using versatile glycosyltransferases (GTs) and sugar-O-methyltransferases (SOMTs). Two GTs, AtUGT89C1 from the Arabidopsis thaliana plant and YjiC from Bacillus licheniformis DSM-13 bacteria, catalyzed the glycosylation reaction. Two SOMTs transferred the methyl group to two specific hydroxy positions in the sugar moiety of genistein rhamnopyranoside, thus diversifying the sugar attached to genistein. Among the biosynthesized compounds, four of the 2-deoxy-D-glycopyranosides, 7-O-(2-deoxy-β-D-arabino-hexopyranosyl)genistein, 4′-O-(2-deoxy-β-D-arabino-hexopyranosyl)genistein, 4′,7-bis-O-(2-deoxy-β-D-arabino-hexopyranosyl)genistein, and 4′,5,7-tri-O-(2-deoxy-β-D-arabino-hexopyranosyl)genistein, and two of the O-methyl rhamnopyranosides, 7-O-(3-O-methyl-α-L-rhamnopyranosyl)genistein and 7-O-(4-O-methyl-α-L-rhamnopyranosyl)genistein, are novel compounds that have not been previously reported. The other glycopyranosides are 7-O-(α-L-rhamnopyranosyl)genistein, 7-O-(β-D-glucopyranosyl)genistein, 4′-O-(β-D-glucopyranosyl)genistein, and 4′,7-O-(β-D-glucopyranosyl)genistein. Microbial production of these novel compounds and other glucopyranosides is appreciable in shake flask culture. This study highlights the application of versatile enzymes in the production of diverse glycosides of medicinally important genistein, which can have positive impacts on a variety of molecular targets in future studies, as shown by genistein with remedied drawbacks.

/pdf/biosynthesis-of-natural-and-non-natural-genistein-glycosides-3ih66tutku.pdf

Prakash Parajuli

Papers

Characterization of regioselective flavonoid O-methyltransferase from the Streptomyces sp. KCTC 0041BP.

Substrate Scope of O-Methyltransferase from Streptomyces peucetius for Biosynthesis of Diverse Natural Products Methoxides

Enzymatic glycosylation of the topical antibiotic mupirocin

Regiospecific biosynthesis of tamarixetin derivatives in Escherichia coli

Biosynthesis of natural and non-natural genistein glycosides