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Highlights • Eight polyhydroxylated naphthoquinone compounds were identified from New Zealand sea urchin species Evechinus chloroticus. • Organic solvent extraction was better in extracting PHNQ than the macroporous resins. • The stability of the E. chloroticus PHNQ pigments is reported for the first time. • The degradation of amino PHNQ under the natural light was more remarkable than PHNQ pigments. Abstract The extraction of polyhydroxylated naphthoquinone (PHNQ) pigments from the shell and spines of the New Zealand sea urchin Evechinus chloroticus was evaluated using six different macroporous resins as an alternative to using organic solvent extraction alone. Four of the resins evaluated in this study (D4006, D4020, D101 and NKA-9) provided the best extraction of PHNQ pigments in terms of the overall adsorption and desorption of E. chloroticus PHNQ pigments from the resins. Organic solvents alone had a higher yield of PHNQs than the resins. The PHNQ composition was characterised by high-performance liquid chromatography (HPLC) with diode‐array detection and mass spectrometry. Five PHNQ compounds (spinochromes E, B, C, A and echinochrome A), and three aminated PHNQ compounds (spinamine E, echinamines A and B) were identified. The pigments were found to be prone to degradation on exposure to light, with the aminated PHNQ pigments being the least stable. [ABSTRACT FROM AUTHOR]

This study investigated the polyhydroxyl-1,4-naphthoquinone (PHNQ) composition and bioactivities of Evechinus chloroticus sea urchin shell and spine waste extracted using the macroporous resins NKA-9, D4020, D4006, and D101. The mineral and protein contents in the shell and spine were found to be 85.21% and 84.14%, 3.85% and 8.96%, respectively. Spine PHNQs extracted using the D4006 resin had the highest total phenolic content (TPC) while the D101 and D4020 resin extracts had a lower TPC (p < 0.05). The best extraction was obtained with the D4006 resin and spine extracts had higher antioxidant activity (DPPH, ABTS, ORAC and FRAP) than shell extracts (p < 0.05). The Minimum Inhibitory Concentration of PHNQ extracts against Escherichia coli and Staphylococcus aureus ranged from 2.5 to 10 mg/mL, with the D4006 resin extract having the best activity. An in silico docking study of spinochrome A and B that is present in the PHNQ extracts, suggested a potent anti-inflammatory activity. The results suggest that macroporous resin extraction of PHNQs from E. chloroticus shell and spine is an effective way to obtain natural bioactives. • Polyhydroxyl-1,4-naphthoquinones (PHNQs) were extracted using macroporous resins. • In vitro antioxidant activities were determined by ORAC, DPPH and FRAP assays. • PHNQ exhibited antimicrobial activity. • Dimer PHNQs exhibited better anti-inflammatory activity than celecoxib. [ABSTRACT FROM AUTHOR]

• E. chloroticus polyhydroxyl-1,4-naphthoquinones were extracted and fractionated. • In vitro antioxidant activities were determined by ORAC, DPPH and FRAP assays. • E. chloroticus PHNQ extracts exhibited antimicrobial activity. • The extracts exhibited anti-inflammatory activity comparable to Celecoxib. This study investigated the bioactivities of polyhydroxyl-1,4-naphthoquinone (PHNQ) extracts from Evechinus chloroticus shell waste. PHNQs were extracted from E. chloroticus shells and spines using different solvents and the crude extracts were fractionated by HPLC. The antioxidant activity of the PHNQ extracts were evaluated by the DPPH, ABTS, ORAC and FRAP assays. Ethyl acetate was the best extraction solvent and spine extracts showed better antioxidant activity than shell extracts (p < 0.05). The HPLC fraction containing spinochrome E showed the highest antioxidant activity (p < 0.05). The Minimum Inhibitory Concentration of the PHNQ crude extracts and the HPLC fractions ranged from 250 to 2500 µg/mL depending on the PHNQ extract and microbial species tested. Treatment by PHNQ extracts resulted in alteration of the morphology of the microbial cell wall as observed by transmission electron microscopy. PHNQ extracts also exhibited anti-inflammatory activity in rats (ED 50 = 8.26 ± 0.22 µg), comparable to that of Celecoxib (6.12 ± 0.18 µg). [ABSTRACT FROM AUTHOR]