Hplc grade hexane

The essential oil was extracted by adopting methodology described by El-Seedi et al., 2012 [25 (link)]. Briefly, the fresh twigs of S. persica roots (1.4 kg) were cut into 20–30 mm long pieces and mixed with 700 mL double-distilled water. The resulting mixture was subjected to hydrodistillation for 4-5 h in a glass distillation apparatus. The collected distillate (oil/water mixture) was extracted three times with HPLC grade hexane (VWR International, Sweden) with the help of a separating funnel. Anhydrous MgSO₄ (Alfa Aeser, UK) was added to the hexane extract to remove any trace of water. After filtration, hexane was evaporated using a rotary evaporator (Buchi Rotavapor R-210, Switzerland) at 20°C under reduced pressure. The essential oil obtained was then weighed and the yield calculated as percentage (w/w) of the total plant material. The essential oil was stored at −20°C in a freezer till further experiments and analyses on GC-MS.

Tigriopus californicus was sourced from Reefphyto Ltd. (Newport, UK). Rhodomonas lens was obtained from the Bigelow National Center for Marine Algae and Microbiota (Maine, USA), Tetraselmis chui was obtained from the Culture Collection of Algae and Protozoa (CCAP, Scottish Marine Institute, Argyll, Scotland), and Nannochloropsis oceanica was obtained from the Norwegian Culture Collection of Algae (NORCCA, Oslo, Norway). Dried Brewers’ yeast was provided by Biomax Ltd. (Elvington, UK). Meso-zeaxanthin powder (10% dry biomass) was obtained from XABC Biotech Co Ltd. (Xi’an, China). The carotenoid standards lutein, zeaxanthin, and zeaxanthin racemic mixture were purchased from CaroteneNature (Lupsingen, Switzerland). Butylated hydroxyltoluene (BHT) was purchased from Sigma-Aldrich (Arklow, Ireland). HPLC grade methyl tert-butyl ether (MTBE), water, and isopropanol were supplied by Fisher Scientific (Dublin, Ireland). HPLC grade hexane and ethanol 96% were supplied by VWR (Dublin, Ireland). Artificial Sea Salt (Tropic Marin^® PRO-REEF) and Evolution Aqua K1 Micro media were purchased to McGuire’s Garden Centre (Waterford, Ireland).

To extract essential oils, 300 g of cut pieces of fresh plant materials was mixed with 600 mL of distilled water and the mixture subjected to hydrodistillation for 4-5 hours using glass distillation apparatus. The distillate (oil/water mixture) was collected and the essential oils were extracted from the distillate with HPLC grade hexane (VWR International, Sweden). Anhydrous magnesium sulfate (VWR International, Sweden) was added to the hexane extract to remove any trace of water. After filtration, hexane was evaporated with a rotary evaporator (Buchi Rotavapor R210, Switzerland). The essentials oils obtained were then weighed and the yields calculated as percentage of fresh starting plant materials.