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This study was conducted to determine the chemical composition of ink from sea hare (Dolabella auricularia) of Pujada Bay, City of Mati, Davao Oriental. The proximate and mineral composition were determined by using the standard official methods of the Association of Official Analytical Chemists (AOAC).  The presence of secondary metabolites was investigated by using different qualitative tests, namely Froth test (saponins), Libermann-Buchard (sterols), Bate-Smith and Metacalf (flavonoids), Dragendorff and Maeyer (alkaloids), Keller-kiliani (glycoside), ferric chloride (tannins) and Bortnträger (anthraquinones). Its antibacterial activity against Escherichia coli and Staphylococcus aureus was determined by using agar well diffusion method. The results for proximate analyses showed that ink contained 90.4 % moisture, 2.044 % ash, 5.324 % crude fat and 0.75 % protein. The mineral analyses were 0.25 % phosphorous, 578 µg/g potassium, 0.662 % sodium, 310.8 µg/g calcium, 664 µg/g magnesium, 2.146 µg/g iron and 1.898 µg/g zinc. Secondary metabolites screening revealed that ink contained saponins, steroids and flavonoids. Further, the ink extract showed weak antibacterial factor.  This is the first study conducted on the ink of sea hare in Davao region and its preliminary results showed that it is a good source of primary and secondary metabolites. These findings can be added to the potential medicinal value of sea hare and a basis for further chemical studies that will hopefully lead to the discovery of compounds with pharmacological importance.

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Chemical investigation of Euphorbia hirta, a folkloric medicinal plant against dengue in the Philippines, disclosed two known flavonoids (quercetrin and myricitrin) together with seven known triterpenes (taraxerone, taraxerol, β-sitosterol, 24-hydroperoxycycloart-25-en-3β-ol, 25-hydroperoxycycloart-23-en-3β-ol, lupeol, and (23E)-cycloart-23-en-3β, 25-diol). The structures were established mainly with 1H and 13C nuclear magnetic resonance (NMR) spectroscopic analyses in comparison with the literature data. These compounds were tested against Japanese encephalitis virus (JEV). Results showed that myricitrin exhibited good inhibition on the production of the infectious viral particle at 100 µM.

The egg strings of sea hare, Dolabella auricularia are economically important to the local fisher folks in Davao Oriental. These are gathered for food consumption or sold in the market. The province of Davao Oriental is one of the country's tourist destinations. Increasing anthropogenic activities are inevitable which can contribute to the levels of trace metal concentrations in the area. The primary purpose of this study was to determine the concentrations of Fe, Zn, Cd, Hg and Pb using atomic absorption spectrophotometer. Trace metals average concentrations in egg strings were found to be 175.67 µg g -1 for Fe, 282.00 µg g -1 for Zn, 0.98 µg g -1 for Cd, 0.01 µg g -1 for Hg and 6.94 µg g -1 for Pb. The Fe and Zn concentrations can supplement the body's requirement needed for normal growth and development based on the Recommended Energy Nutrient Intakes for Filipinos. Moreover, the mercury concentration was lower than the existing standard set by FAO No. 21 of 2001. However, the amount of Cd and Pb were noticeably higher than the maximum level. This investigation represents the first study so far on the levels of trace metals in egg strings of sea hare from Pujada Bay, Davao Oriental. The results of this study provide baseline information for the conduct of further investigation to monitor and evaluate the trace metal concentrations and the contributing anthropogenic activities. These will help the local government in the formulation of policies for a sustainable development.