Antimycobacterial and anti-inflammatory activities of fractions and substances from Erythrina verna Vell focusing on dual severe TB treatment approach.

Tuberculosis remains a major health problem worldwide. Drug-resistant and hypervirulent Mycobacterium tuberculosis (Mtb) strains can lead to a hyperinflammatory response and necrotic pathology in hyper-reactive individuals that require adjunctive treatment. Plant-derived substances have been investigated for TB treatment, among which flavonoids stand out. We evaluate the anti-Mtb, anti-inflammatory and cytotoxicity activities of fractions and substances 1, 2 and 3 isolated from Erythrina verna through a bioassay guided fractionation. Seven fractions (1, 3-5 and 7-9) obtained from dichloromethane E. verna extract inhibited NO production (IC50 ≤ 15 µg/mL) with none or poor cytotoxic effect, while the fractions 4 and 5 notably reduced TNF-a production. Fractions 4, 6 and 9 suppressed Mycobacterium growth with MIC50 ≤ 20 µg/mL. Fraction 4 was the most potent due to dual biological activities. Erythratidinone and alpinumisoflavone inhibited the growth of Mtb H37Rv and hypervirulent strain in bacterial cultures (MIC50 ≤ 20 µg/mL), with erythratidinone standing out in reducing intracellular growth of Mtb H37Rv (5.8 ± 1.1 µg/mL). Alpinumisoflavone and erythratidinone were capable of inhibiting NO and TNF-α production besides showing significant inhibitory effects against Mycobacterium tuberculosis strains with low toxicity in macrophages. Both substances are promising for further studies focusing on an anti-TB dual treatment approach.

Methodology for porphyrin isolation by high-performance countercurrent chromatography.

Countercurrent chromatography is a versatile technique for the isolation of a wide variety of plant substances. However, little attention has been devoted to the application of this technique for the isolation of porphyrins. This class of compounds are of great importance in the medical area and in photocatalysis due to their heterocyclic structure, composed of four modified pyrrol subunits interconnected on their a carbon atoms by methinic bridges. The methanol extract of Gallesia integrifolia was partitioned using different solvents; the dichloromethane fraction was then submitted to countercurrent chromatography. The solvent system composed of n-hexane, ethyl acetate, methanol, and water (1:2.5:2.5:1) was chosen to perform the chromatographic analysis due to the enhanced solubility and the best distribution coefficients of the target compounds. Two porphyrins were isolated by this method and identified as 13(2)-hydroxypheophorbide a methyl ester and pheophorbide a, methyl ester. The solvent system proposed provided good distribution coefficients for both substances (1.27 and 1.87, respectively), and a high resolution factor.