Use of Natural Antioxidants from Newfoundland Wild Berries to Improve the Shelf Life of Natural Herbal Soaps
Oludoyin Adigun,
Charles Manful,
Natalia Prieto Vidal,
Abira Mumtaz,
Thu Huong Pham,
Peter Stewart,
Muhammad Nadeem,
Dwayne Keough,
Raymond Thomas
Affiliations
Oludoyin Adigun
School of Science and the Environment/Boreal Ecosystem Research Initiative, Grenfell Campus, Memorial University of Newfoundland, 20 University Drive, Corner Brook, NL A2H 5G4, Canada
Charles Manful
School of Science and the Environment/Boreal Ecosystem Research Initiative, Grenfell Campus, Memorial University of Newfoundland, 20 University Drive, Corner Brook, NL A2H 5G4, Canada
Natalia Prieto Vidal
School of Science and the Environment/Boreal Ecosystem Research Initiative, Grenfell Campus, Memorial University of Newfoundland, 20 University Drive, Corner Brook, NL A2H 5G4, Canada
Abira Mumtaz
School of Science and the Environment/Boreal Ecosystem Research Initiative, Grenfell Campus, Memorial University of Newfoundland, 20 University Drive, Corner Brook, NL A2H 5G4, Canada
Thu Huong Pham
School of Science and the Environment/Boreal Ecosystem Research Initiative, Grenfell Campus, Memorial University of Newfoundland, 20 University Drive, Corner Brook, NL A2H 5G4, Canada
Peter Stewart
School of Science and the Environment/Boreal Ecosystem Research Initiative, Grenfell Campus, Memorial University of Newfoundland, 20 University Drive, Corner Brook, NL A2H 5G4, Canada
Muhammad Nadeem
School of Science and the Environment/Boreal Ecosystem Research Initiative, Grenfell Campus, Memorial University of Newfoundland, 20 University Drive, Corner Brook, NL A2H 5G4, Canada
Dwayne Keough
School of Life Sciences and Environment, Algoma University 1520 Queen St E., Sault Ste. Marie, ON P6A 2G4, Canada
Raymond Thomas
School of Science and the Environment/Boreal Ecosystem Research Initiative, Grenfell Campus, Memorial University of Newfoundland, 20 University Drive, Corner Brook, NL A2H 5G4, Canada
Antioxidants are important bio-regulators and suppressors of oxidation and are useful in enhancing the shelf life of consumer products. Formulated natural herbal soaps contain ingredients with antioxidant activities, but it is unknown how this influences shelf life. Herein, we evaluated whether natural additives or wild berry extracts were effective in improving the quality of natural herbal soaps. Three natural soaps, base bar (BB), forest grove (FG), and hibiscus rosehip (HR), were formulated using several wild berry extracts or natural additives and evaluated against similar commercial brands. The total phenolic content (TPC) of BB and FG infused with partridgeberry and HR with rosemary was 35.22, 44.72, and 33.26 µmole quercetin equivalent/g soap, while the total antioxidant activity (TAA) was 125.20, 119.23, and 126.94 µmole Trolox equivalent/g soap, respectively. Conversely, the commercial brand (BSG) with the highest TPC (56.24 µmole) contained lower TAA (59.68 µmole). As expected, the TPC and TAA of natural soaps were strongly correlated, and the majority (55−82%) of the polyunsaturated di/triacylglycerols remained unsaponified. Some extracts were inhibitory, while others promoted microbial growth. The results indicate that natural antioxidants from some Newfoundland wild berries have applications in improving the shelf life of natural herbal soaps, but care must be taken with the choice of berry used in the final soap formulation.
