Test protimikrobne učinkovitosti izbranih snovi naravnega izvora v dermalni formulaciji z uporabo Aspergillus brasiliensis in Candida albicans

Lah, Nadine (author), Kočevar Glavač, Nina (mentor), Ravnikar, Matjaž (comentor)

Ker se v zadnjih letih pojavljajo tako upravičeni kot tudi neupravičeni dvomi glede varnosti sinteznih konzervansov v kozmetičnih izdelkih in se hkrati dviga trend uporabe naravnih sestavin, kozmetična podjetja iščejo alternativne rešitve konzerviranja z uporabo protimikrobnih snovi naravnega izvora. Eden izmed glavnih izzivov kozmetične industrije je zagotavljanje mikrobiološke neoporečnosti, saj je lahko prevelika vsebnost mikroorganizmov zdravju nevarna. V magistrski nalogi smo preizkusili učinkovitost 33 protimikrobnih snovi naravnega izvora. S preizkusom določanja celokupnega števila aerobnih bakterij, kvasovk in plesni Evropske farmakopeje smo preverili mikrobiološko ustreznost izdelanih emulzij z metodo štetja zraslih kolonij na petrijevkah. Kriterija ni izpolnila le 1,0-odstotna formulacija fermenta Lactobacillus pod tržnim imenom Leucidal® Liquid PT, saj smo opazili kontaminacijo petrijevke, ki je za več kot 8-krat presegala največje sprejemljivo število mikroorganizmov (20 CFU/g). V izzivnem testu po standardu ISO smo v testne dermalne emulzije z različnimi protimikrobnimi snovmi različnih koncentracij inokulirali znano koncentracijo mikroorganizmov A. brasiliensis ali C. albicans in po časovnih točkah opazovali, ali ustrezajo kriterijem sprejemljivosti. Preizkus učinkovitosti konzervansov za A. brasiliensis ni bil uspešen (ne ustreza niti kriteriju A niti kriteriju B) za 3 formulacije s protimikrobnimi snovmi naravnega izvora: 0,2 % Geogard® 221 (benzil alkohol, dehidroocetna kislina), 1,5 % Verstatil® SL (natrijeva sol levulinske kisline, kalijev sorbat) in 3,0 % Verstatil® Synacide (natrijeva sol levulinske, salicilne in janežne kisline). Pri sedmih formulacijah smo opazili organoleptične spremembe: 2,0 % Arborcide® OC (filtrat fermenta Leuconostoc), 4,0 % Arborcide® OC (filtrat fermenta Leuconostoc), 2,0 % Leucidal® Liquid (filtrat fermenta korenine redkvice), 2,0 % Leucidal® Liquid Complete (filtrat fermenta korenine redkvice, izvleček plodu kokosa z Lactobaccilus), 0,25 % PlantservativeTM WSR (izvleček cvetov navadnega in japonskega kovačnika), 2,0 % Dermosoft® 1388 ECO (natrijeva sol levulinske in janežne kisline) in 0,05 % Dermosoft® Anisate ECO (natrijeva sol janežne kisline). Čeprav so vse ustrezale kriteriju A, smo jih označili kot protimikrobne snovi naravnega izvora, ki ne nudijo zadostne zaščite dermalne formulacije pred razrastom mikroorganizmov.

• Language: Slovenian
• Keywords: Aspergillus brasiliensis, Candida albicans, ISO 11930, Eur. Ph. 2.6.12., preizkus mikrobiološke kakovosti nesterilnih farmacevtskih izdelkov, naravni konzervansi, kozmetični izdelki
• Work type: Master's thesis/paper
• Organization: FFA - Faculty of Pharmacy
• Year: 2022
• PID: 20.500.12556/RUL-141637
• Publication date in RUL: 03.10.2022

Secondary language

• Language: English
• Title: Antimicrobial test of selected compounds of natural origin in a dermal formulation using Aspergillus brasiliensis and Candida albicans

Abstract

Since both, justified and unjustified doubts regarding the safety of synthetic preservatives in cosmetic products have appeared in recent years and at the same time the trend of using natural ingredients is rising, cosmetic companies are forced to look for alternative solutions using antimicrobial substances of natural origin. One of the main challenges of the cosmetic industry is the regulation of microbiological integrity, as the content of microorganisms can be too high and dangerous to health. In the master's thesis, we tested the efficacy of 33 antimicrobial substances of natural origin. We checked the microbiological adequacy of the produced emulsions by the method of counting grown colonies on petri dishes with the test of determining the total number of aerobic bacteria, yeasts and moulds of the European Pharmacopoeia. Only the formulation of 1.0 % Lactobacillus ferment under the trade name Leucidal® Liquid PT did not meet the criteria, as we observed contamination of the petri dish that exceeded the maximum acceptable number of microorganisms by more than 8 times. In a challenge test according to the ISO standard, we inoculated dermal emulsions with a known concentration of A. brasiliensis or C. albicans and observed whether they met the acceptance criteria at specific time points. The preservative efficacy test for A. brasiliensis did not meet neither criterion A nor criterion B for 3 formulations with antimicrobial substances of natural origin: 0.2% Geogard® 221 (benzyl alcohol, dehydroacetic acid), 1.5% Verstatil ® SL (sodium salt of levulinic acid, potassium sorbate) and 3.0% Verstatil® Synacide (sodium salt of levulinic, salicylic and aniseic acids). Organoleptic changes were observed in seven formulations: 2.0% Arborcide® OC (Leuconostoc ferment filtrate), 4.0% Arborcide® OC (Leuconostoc ferment filtrate), 2.0% Leucidal® Liquid (radish root ferment filtrate), 2, 0% Leucidal® Liquid Complete (radish root ferment filtrate, coconut fruit extract with Lactobaccilus), 0.25% PlantservativeTM WSR (common and Japanese blackberry flower extract), 2.0% Dermosoft® 1388 ECO (levulinic and anisic acid sodium salt) and 0.05% Dermosoft® Anisate ECO (sodium salt of aniseic acid). Although all seven met criterion A, they are not antimicrobial substances of natural origin that would provide sufficient protection against the growth of microorganisms.

• Keywords: Aspergillus brasiliensis, Candida albicans, ISO 11930, Eur. Ph. 2.6.12., Microbiological examination of non-sterile products, natural preservatives, cosmetic products