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The Physic Nut seed oil extracted by screw pressing was assayed for free radical scavenging activity by DPPH and tyrosinase inhibition activity by the dopachrome methods. The oils gave both activities similar to vitamin C. The maximum loading of the oil in niosomes composed of Tween 61/cholesterol at 3:7 molar ratio prepared by chloroform film method with sonication was 1%w/v. The niosomes were stable at 28ºC for 8 weeks with an average size determined by dynamic light scattering (DLS) of about 120 nm. The oil entrapped in niosomes gave higher scavenging and tyrosinase inhibition activity than the unentrapped oil of about 3-5 and 1-2 times (p < 0.1), respectively. This study has indicated the potential enhancement of free radical scavenging activity and tyrosinase inhibition activity of Physic Nut oil by entrapping in niosomes.

A new species of the genus Pinctada is described from samples collected from the east coast of Phuket Island, Thailand in the Andaman Sea. Pinctada phuketensissp. nov. is distinguished from other species on both molecular and morphological data. Morphologically, the valves of P. phuketensis are characterized by a slightly developed to undeveloped posterior auricle, a small, narrow slit-like byssal notch, the absence of hinge teeth, and a pale to transparent non-nacreous border, with a few dark brown or red blotches. This new species resembles P. fucata but differs by its smaller size and the absence of hinge teeth. Phylogenetic analyses based on both mitochondrial (COI) and nuclear (18S rDNA, ITS1 and ITS2) genes and species delimitation using COI data strongly support that P. phuketensis is a distinct species, which is closely related to Pinctada albina and Pinctada nigra.