Rose bengal chloramphenicol agar

The Moringa oleifera leaves were collected in Luanda, Angola (8°57′24.9′’ S, 13°13′02.9′’ E) and ground to obtain a homogeneous powder (particle size < 250 μm). To produce fresh pasta, wheat flour (type 55), medium size eggs, salt, and olive oil were purchased from a supermarket in Porto, Portugal.
To extract the phenolic compounds, ethanol (Ref. 83813.360, C₂H₆O, CAS 64-17-5) was acquired from VWR (Radnor, PA, USA). For the characterisation of the extract, sodium carbonate (Ref. 13418, CNa₂O₃, CAS 497-19-8) was obtained from Honeywell (Charlotte, NC, USA), while Folin–Ciocalteu reagent (Ref. 47641), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (Ref. A1888, C₁₈H₂₄N₆O₆S₄, CAS 30931-67-0) and 2,2-diphenyl-1-picrylhydrazyl (Ref. D9132, C1₈H₁₂N₅O₆, CAS 1898-66-4) were acquired from Sigma-Aldrich (St. Louis, MO, USA). For the microbial analysis, m-Lauryl Sulfate Broth (Ref. 0734) was obtained from Sigma-Aldrich, agar (Ref. J637, CAS 9002-18-0) was purchased from VWR and Rose-Bengal Chloramphenicol Agar (Ref. 1.00467.0500) was acquired from Merck (Darmstadt, Germany). Water purification was performed using a purification equipment (electrical resistance of 18.2 W) from Millipore (Burlington, MA, USA).

Aliquots (10 g) of chopped fresh and dried sea fennel leaves were added to 90 mL of 0.1% (w v⁻¹) sterile peptone water and homogenized using a Stomacher 400 Circulator apparatus (International PBI, Milan, Italy) for 2 min at 230 rpm. The homogenates were ten-fold serially diluted in the same diluent and subjected to enumeration of (i) Enterobacteriaceae on Violet Red Bile Glucose Agar (VRBGA) (VWR, Radnor, PA, USA) incubated at 37 °C for 24 h; (ii) yeasts and molds on Rose Bengal Chloramphenicol agar (VWR) incubated at 25 °C for 5 days; and (iii) mesophilic aerobic bacteria and spore-forming bacteria on Plate Count Agar (PCA) (VWR) incubated at 30 °C for 72 h. For the enumeration of spore formers, prior to analysis, each homogenate was subjected to heat treatment at 80 °C for 10 min, followed by cooling in iced water, to inactivate vegetative cells. The results of viable plate counting were expressed as mean Log CFU g⁻¹ of three replicates per batch ± standard deviation.