The prevention of fish spoilage by high antioxidant Australian culinary plants: Shewanella putrefaciens growth inhibition

Abstract

Summary Shewanella putrefaciens is a marine bacterium and a major microbial cause of spoilage in low temperature stored seafood. A survey of fruits and culinary herbs was undertaken on Australian plants with high antioxidant capacities. Twenty‐eight extracts from thirteen plant species were investigated for the ability to inhibit S. putrefaciens growth. Of these, eight extracts (28.6%) substantially inhibited S. putrefaciens growth. The muntries (Kunzea pomifera), lemon aspen (Acronychia acidula) and desert lime (Citrus glauca) extracts were efficient anti‐S. putrefaciens agents, with MIC values ≤3000 μg mL−1. Of these, the muntries methanolic extract was the most potent growth inhibitor (MIC = 2240 μg mL−1). The aqueous desert lime extract was also an effective growth inhibitor (MIC of 3857 μg mL−1), whilst the methanolic bush tomato (Solanum aviculare), aqueous muntries and Davidson's plum (Davidsonia pruriens) extracts displayed moderate S. putrefaciens growth inhibition. All extracts were nontoxic in the Artemia fransiscana bioassay, with LC50 values (>1000 μg mL−1). Nontargeted HPLC‐QTOF mass spectroscopy (with screening against three compound databases) putatively identified twenty compounds that were present in both inhibitory muntries extracts. The low toxicity of these extracts and their inhibitory bioactivity against S. putrefaciens indicates their potential as natural fish and seafood preservatives.

Aleurites moluccanus (l.) Willd. Extracts Inhibit the Growth of Bacterial Triggers of Selected Autoimmune Inflammatory Diseases

“…A high antioxidant capacity has been postulated as being responsible for the medicinal properties of many plants. [26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44] In particular, antioxidants have been linked to antibacterial, antifungal and antiviral activities, as well as anticancer properties. 26-44 . However, other studies have indicated that antioxidants may protect cells from oxidative stress and thus protect against cell death.…”

“…[32][33][34] Briefly, 100 µL of each bacterial culture was grown in 10 mL of fresh nutrient broth until they reached a count of ~10 8 cells/mL. A volume of 100 µL of the bacterial suspension was spread onto nutrient agar plates and extracts were tested for antibacterial activity using 5 mm sterilised filter paper discs.…”

Swainsona Formosa (G.Don) Joy Thomp. Solvent Extractions Inhibit the Growth of a Panel of Pathogenic Bacteria

“…[18][19][20] Briefly, 100 µL of each bacterial culture was grown in 10 mL of fresh nutrient broth until they reached a count of ~10 8 cells/mL. A volume of 100 µL of the bacterial suspension was spread onto nutrient agar plates and extracts were tested for antibacterial activity using 5 mm sterilised filter paper discs.…”

Cinnamomum Oliveri F. M. Bailey Leaf Solvent Extractions Inhibit the Growth of a Panel of Pathogenic Bacteria

“…[12][13][14] Briefly, 100 µL of each bacterial culture was grown in 10 mL of fresh nutrient broth until they reached a count of ~10 8 cells/mL. A volume of 100 µL of the bacterial suspension was spread onto nutrient agar plates and extracts were tested for antibacterial activity using 5 mm sterilised filter paper discs.…”