Glacial acetic acid

Single component Sudan dye standards (purity >96.0%) for Sudan I, II, III, and IV (Sigma Aldrich). GC grade acetone (purity >99.0%), and LC grade acetonitrile (purity >99.9%) were purchased from Merck KGaA, Darmstadt, Germany. The glacial acetic acid (purity >99.7%) was from Daejung Chemicals, Siheung, Korea. MilliQ ultrapure deionized water (18.2 MΩ) filtered through MilliQ polisher (DI water), AOAC Method 2007.01 roQ QuEChERS extraction salts (6.0 g MgSO₄ + 1.5 g NaOAc) were purchase from Phenomenex Inc.

The peroxide value was measured according to method of Cho et al. [23 (link)] and expressed in meq of peroxide/kg. Briefly, 1 g of each oleogel was dissolved with the solution of glacial acetic acid (15 mL) and chloroform (10 mL) (Daejung Chemicals and Metals Co., Ltd., Siheung, Korea), followed by the addition of saturated potassium iodine solution (1 mL). After left for 10 min in the dark, the mixture was blended with 30 mL of distilled water and then titrated against 0.01 N Na₂S₂O₃ including 1% starch solution as an indicator. The end point was determined when the coloration by starch disappeared. The peroxide value of oleogel was analyzed every 7 days while stored at 60 °C for 28 days.

Pitavastatin was obtained as a gift sample from CCL Laboratories Pvt., Ltd., Lahore, Pakistan. PEG 200, PEG 400, PEG 600, cinnamon oil, olive oil, ginger oil, sesame oil, virgin coconut oil, and castor oil were purchased from Sigma–Aldrich Gmbh, Darmstadt, Germany. Methanol, acetonitrile, Tween 20, Tween 40, Tween 60, and Tween 80 were acquired from Merck, Darmstadt, Germany. Triton X-100 was obtained from Daejung Chemicals, Korea. Sodium hydroxide, glacial acetic acid, and potassium dihydrogen phosphate were obtained from Daejung Chemicals, Korea. Dimethyl sulfoxide (DMSO) and 4-bromophenylboronic acid were purchased from Merck, Darmstadt, Germany.

Oleanolic acid, hederagenin, and cholesterol were purchased from Sigma‐Aldrich. Phytolaccagenic acid was purchased from Carbosynth. Oleanolic acid and phytolaccagenic acid were dissolved in Ethyl acetate while hederagenin was dissolved in methanol. Then, each standard was prepared at a concentration of 1 mg/ml. Ammonia water, N,O‐Bis(trimethylsilyl) trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane (TMCS), anhydrous pyridine, ethanol, rutin, gallic acid, folin–ciocalteu reagent, 2,2‐diphenyl‐1‐picrylhydrazyl, 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) diammonium salt, phosphate buffer (pH 6.6), potassium hexacyanoferrate(III), trichloroacetic acid, and iron(III) chloride were purchased from Sigma‐Aldrich. Sodium sulfate anhydrous, hydrochloric acid, sodium carbonate, sodium hydroxide, petroleum ether, glacial acetic acid, and sulfuric acid were purchased from Daejung Chemicals & Metals. Ethyl acetate and methanol were purchased from J. T Baker.

For enumeration of Lactobacillus species, when their presence was indicated on the product specification, 0.1 mL of the product cell suspension was spread on de Man Rogosa Sharpe (MRS) agar (BD Difco, Detroit, MI, USA) and let dry. Only the highest three dilutions were used per sample and plated by duplicate. The plates were incubated for 48 h at 37 °C in anaerobic chamber (Whitley DG250 Anaerobic Workstation, Don Whitley Scientific Limited, Bingley, West Yorkshire, UK). For products indicating Lactobacillus acidophilus as part of its formulation, the sample suspensions were plated on Modified Rogosa agar pH 5.5 and incubated under the same conditions following the same approaches. The formulation for one liter of Modified Rogosa agar consisted of 10 g Bacto™ tryptone, 5 g yeast extract (BD Difco), 20 g D-glucose, 6 g KH₂PO₄, 1 g Tween 80, 2 g triammonium citrate, 0.575 g MgSO₄·7H₂O, FeSO₄·7H₂O (Sigma-Aldrich, St. Louis, MO, USA), 0.110 g MnSO₄·H₂O (Duksan Chemicals) and 15 g agar (LPS Solution, Daejeon, South Korea). The pH was adjusted to 5.5 using glacial acetic acid (Daejung Chemicals, Siheung, South Korea) prior autoclaving at 121 °C for 10 min to avoid hydrolyzation of agar due to low pH. Based on the colony counts the CFU/g was were determined for each product.