Potassium iodide

PLTX standard (from Palythoa tuberculosa) was purchased from Wako Chemicals GmbH (Germany). For quantitative analysis, concentrations of the target compounds (isoPLTX and OVTX -a to -g analogues) were determined as their respective PLTX equivalents. The stock standard solution (100 µg mL⁻¹) was individually prepared by weight in MeOH:H₂O (80:20, v/v) in a precision balance (Mettler Toledo AG425, Columbus, OH, US). For quantification, calibration solutions of PLTX were prepared from the stock standard solution at concentrations ranging from 0.005 to 5 µg mL⁻¹ in MeOH:H₂O (80:20, v/v). All standard solution aliquots were stored at −20 °C until use. LC–MS grade (>99%) water and organic solvents (acetonitrile and formic acid) were from Sigma-Aldrich (Steinheim, Germany). The mobile phases were filtered through 0.22 µm Nylon membrane filters (Whatman, Clifton, NJ, USA) before use. Nitrogen gas (99.95%, from Linde, Barcelona, Spain) was used as sheath gas and auxiliary gas in the ionization source. The 25 mm GF/F glass fiber filters were purchased from Whatman (Clifton, NJ, USA). The Lugol solution used to fix culture samples for Ostreopsis cell counts was prepared following Andersen and Throndsen (2004), with potassium iodide (KI) and iodine (I₂) from Merck (Darmstadt, Germany) [77 ].

Concentrated sulphuric acid, mix catalyst (96% sodium sulphate anhydrous, 3.5% cuprum sulphate sulphate, 0.5% selenium dioxide, sodium hydroxide (NaOH), sulphuric acid (H₂SO₄), boric acid, petroleum ether, n-hexane, iodine reagent, starch, potassium acetate, and potassium iodide were purchased from Merck (Kenilworth, New Jersey, USA). While, ethanol, methanol, acetone, acetic acid (C₂H₄O₂), hydrochloric acid, 1 M phosphate buffer solution, alpha amylase from porcine pancreas, alpha glucosidase enzyme from Saccharomyces cerevisiae, PNPG (4-Nitrophenyl-α-d-glucopranoside), and acarbose were purchased and from Sigma (St. Louis, Missouri, USA). All the authentic standard (HPLC grade) from Sigma. The standards include ellagic acid, kaempferol, chlorogenic acid, apigenin, myricetin, p-coumaric acid, proto-catechuic acid, mangiferin, ethyl gallate, vanillic acid, trans-cinnamic acid, epicatechin, catechin, quercetin hydrate, gallic acid, quercetin, ascorbic acid, and catechin.

Magnesium nitrate hexahydrate (Mg(NO₃)₂ 6H₂O) was obtained from Sigma-Aldrich. Gallium nitrate hydrate (Ga(NO₃)₃ xH₂O, 99.9%) was purchased from Alfa Aesar. Potassium iodide (KI) and sodium carbonate (Na₂CO₃) were supplied by Merck Millipore. Potassium hydroxide (KOH) was obtained from Carlo Erba Reagents. Brucite (Mg(OH)₂) was obtained from Nacalai Tesque. Sodium dodecyl sulfate (C₁₂H₂₅NaO₄S, >95.0%), hexanol (C₆H₁₄O, >98.0%), and benzene (C₆H₆, >99.5%) were supplied by Tokyo Chemical Industry Co., Ltd. These chemicals were used without further purification. Deionized water was obtained from a Milli-Q system (18.2 MΩ-cm, Merck Millipore, Darmstadt, Germany).

Kraft lignin (Sigma-Aldrich, Steinheim, Germany), hexadecyl(trimethyl)ammonium bromide (Sigma-Aldrich, Steinheim, Germany) and ethyl alcohol were used to prepare lignin-based spherical structures. The particles were obtained with the use of three different lignin-to-CTAB ratios: (i) 1 part by weight of Kraft lignin per 1 part by weight of surfactant (1:1), (ii) 2 parts by weight of Kraft lignin per 1 part by weight of surfactant (2:1), and (iii) 4 parts by weight of Kraft lignin per 1 part by weight of surfactant (4:1).
Cilazapril monohydrate (Biofarm; serial number 1621816, Poznan, Poland) was used to prepare the final products. Methanol and acetonitrile (Merck, Darmstadt, Germany) were of HPLC grade. Monobasic potassium phosphate, sodium chloride, sodium nitrate, sodium bromide, potassium iodide, sodium iodide, and orthophosphoric acid (Merck, Darmstadt, Germany) were also used. All reagents and solvents were used as supplied without further purification.

All reagents are used as
received without purification, unless otherwise indicated. 1-Bromododecane,
pentaerythritol, and palladium on activated carbon (10% Pd, unreduced)
were purchased from Acros Organics. triethylene glycol monomethyl
ether, triethylene glycol, p-toluenesulfonyl chloride,
methyl 3,5-dihydroxybenzoate, benzaldehyde, 4-(dimethylamino)pyridine
(DMAP), p-toluenesulfonic acid monohydrate, N,N′-dicyclohexylcarbodiimide (DCC),
and benzyl bromide were products from Sigma-Aldrich. Dimethylformamide
(DMF), potassium carbonate (K₂CO₃), sodium hydroxide
(NaOH), sodium carbonate (Na₂CO₃), dichloromethane
(DCM), and methanol were purchased from Thermo Fisher Scientific.
Methyl 3,4-dihydroxybenzoate was bought from TCI Europe NV. Ethanol
(EtOH) and tetrahydrofuran (THF) were products from VWR International.
Potassium hydroxide (KOH) was bought from J.T.Baker, Avantor. Hydrochloric
acid (HCl, 37%) and potassium iodide (KI) were purchased from Merck.
Dry THF and dry DCM were obtained by passing solvents over activated
alumina columns in a MBraun MB SPS800 under nitrogen and stored under
argon. Ultrapure Milli-Q water (QPOD Milli-Q purification system,
18.2 MΩ) was used for the preparation of all nondeuterated aqueous
solutions.

All chemicals of research grade were used for experimental work. Magnesium chloride, potassium dihydrogen phosphate, sodium bicarbonate, potassium chloride, magnesium sulphate, glucose, sodium dihydrogen phosphate (Merck, Darmstadt, Germany), and sodium chloride (BDH Laboratory Supplies, Poole, England) were used for physiological solution preparation. Carbachol (CCh), acetylcholine chloride (Ach) and loperamide (Sigma Chemical Co., St. Louis, MO) were utilized as standards and castor oil (Marhaba Laboratories, Lahore, Pakistan) for the induction of diarrhoea. Whereas chloroform, hydrochloric acid, benzene, sulphuric acid, iodine, picric acid (BDH Laboratory Supplies, Poole, England), ammonium hydroxide, ferric chloride (Sigma Chemical Co., St. Louis, MO), ethanol, ammonia solution (Saba Saleem Industries and Fine Chemicals, Karachi, Pakistan), sodium hydroxide (Sigma Aldrich Laborchemikalien GmbH, Steinheim am Albuch, Germany), benzene, lead acetate, and potassium iodide (Merck, Darmstadt, Germany) were used in phytochemical analysis of crude extract.
Distilled water was used for the preparation of standard solutions, dilution, and physiological salt solutions (Tyrode’s and Kreb’s solutions). Physiological salt solutions and dilutions of standard drugs were freshly made on the day of the experiment by the method of Naz et al. (2016 ).