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Extraction of Martinella obovata bark. Naomi Bryner. Overview - Genus. Bignoniaceae family 120 genera, 800 species Found in Central and South America Tropical rainforests Versatile plant Horticulture, food, crafts, timber, dyes, rituals, and medicine. Overview - Species.
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Extraction of Martinella obovata bark Naomi Bryner
Overview - Genus • Bignoniaceae family • 120 genera, 800 species • Found in Central and South America • Tropical rainforests • Versatile plant • Horticulture, food, crafts, timber, dyes, rituals, and medicine
Overview - Species • Eye medication • 13 ethnolinguistic groups • 8 S. American countries • Amazon Indian tribes • ‘yuquilla’ • From fleshy root bark • Stripped, pounded, and strained • Applications for curing conjunctivitis • Martinelline • Martinellic acid
Research goals • Investigate processes for pre-extraction treatment of root bark • Develop a protocol for extraction • Perform FCC and identify useful fractions via TLC • Isolate martinelline and martinellic acid • Characterize the compounds via spectroscopic methods
Pre-extraction treatment • Dr. Halligan’s provisions • John Beck @ SBC • Stripping bark from twigs and branches • Tedious & timely • 37.3 g bark material obtained • Milling the plant material • Blender & solvent
Extraction • Merck Research Labs 1995 • CH2Cl2/MeOH(1:1) • Bark & solvent • Sat @ rt overnight • Filtered out solids • Evaporated to drier conditions • 6.09 g slimy residue
Fractionation Solvent search FCC Column Length – 30 cm Diameter – 6 cm Silica gel – 18 cm Sand – 1 cm Gradient (Hex/EtOAc) Tubes 1-20 (8:1) Tubes 21-138 (4:1) Tubes 139-156 (1:1) Tubes 157-160 EtOAc • Round 1 • HE/EtOAc (1:1) • CH2Cl2/MeOH (95:5) • Round 2 • HE/EtOAc (2:1) • HE/EtOAc (4:1) • Round 3 • HE/EtOAc (8:1)
TLC Analysis – Hex/EtOAc (4:1) F1 Solvated fractions 111 to 160 turned from pale green to pale then dark yellow. The transition occurred at F6, making F6 visually difficult to classify as either color. F2 F3 F4 F6 F5 Treated with vanillin stain F5
Fraction summary • F1: Fractions 3-12 • Blue/black on TLC plateRf= 0.69 • Oily yellow, 0.9508 g • F2: Fractions 35-49 • Pink on TLC plateRf= 0.33 • Pale green powder, 1.0286 g • F3: Fractions 73-84 • Pink/red on TLC plateRf= 0.13 • Thin yellow film, 0.0471 g • F4: Fractions 111-125 • Discard – same Rf as F5 & F6Much fainter on TLC plate • Solvated fraction pale in color • F6: Fractions 126-130 • Pink/red on TLC plateRf = 0.10 • Dark green powder, 0.2404 g • F5: Fractions 131-160 • Pink/red on TLC plateRf= 0.08 • Yellow/tan powder, 0.9731 g
Final thoughts Conclusions Future Work HPLC to complete isolation UV-vis Identify! LC-MS Complete NMR Antibacterial properties Potency Killing mechanism • IR analysis was inconclusive • NMR study was cut short • F5 & F6 comparison • May be multiple compounds present • May apply to more fractions
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