First report of anti-inflammatory chromenyl derivatives from the spineless cuttlefish Sepiella inermis

Abstract

The spineless cuttlefish Sepiella inermis encompasses a major share in the marine fisheries sector, and represents as a culinary delicacy in many cultures. Bioactivity-guided fractionation of methanol:ethyl acetate (MeOH:EtOAc, 1:1) extract of the edible parts of the species ensued in identification of two hexahydro chromenyl analogues namely, methyl 7-ethyl-hexahydro-8a-methyl-2H-chromene-4-carboxylate (1) and methyl 1-acetoxy-hexahydro-3-methyl-3-propyl-1H-isochromene-4-carboxylate (2). The isolated metabolites were checked for their radical scavenging and anti-inflammatory potentials by selective in vitro models. The isochromenyl derivative exhibited potential 2,2-diphenyl-1-picryl-hydrazil and 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (IC₅₀?<?0.45?mg mL^?1) radical-scavenging capacities along with pro-inflammatory cyclooxygenase-2 (COX-2) (IC₅₀ 0.75?mg mL^?1) and 5-lipoxygenase (5-LOX) (IC₅₀ 0.77?mg mL^?1) inhibitory activities. The titled compounds displayed the selectivity indices (IC₅₀ anti-COX-1/IC₅₀ anti-COX-2) greater than 1.25, in comparison with synthetic anti-inflammatory drug ibuprofen (0.44), which attributed to their greater selectivity towards inducible pro-inflammatory enzyme COX-2.     

Redox activity of melanin from the ink sac of Sepia officinalis by means of colorimetric oxidative assay

The redox properties of natural extract from cuttlefish ink sac (Sepia officinalis) and synthetic melanin used as a biomimetic in melanin structural investigation were determined by comparison of this phenol-based heterogeneous pigment with gallic acid used as a standard in Folin–Ciocalteu colorimetric assay widely employed for characterisation of oxidative properties of biomaterials. Reactivity of sepia melanin reported here is much higher than previously indicated and this protocol should allow the redox characterisation of all melanins irrespective of their origin and composition.     

Solid‐phase extraction of drugs with cuttlefish bone powder as a sorbent

We investigated cuttlefish bone powder for the solid‐phase extraction of naproxen, ibuprofen, and carbamazepine. The basic principles controlling the extraction are presented to aid in the choice of the nature and quantity of the extracting phase according to the sample matrix and the solute properties, based on the mechanisms of phase retention. Their retention mechanism is based on hydrogen bonding and electrostatic interactions. The results show a significant recovery rate for the three drugs, selectivity, and low cost. The method has successfully reduced the amount of tested pharmaceuticals with recoveries >87% at pH 4.