Background:Ceratonia siliqua L. (Carob tree) is a Mediterranean evergreen, well known for its medicinal properties. The different parts of Carob were proven to exert antidiabetic, antibacterial, antifungal, and antiproliferative effects. Hence, the present paper aims to validate the positive correlation between the high antioxidant activity of carob seed peels and the improvement of negative symptoms of schizophrenia. Materials & Methods: The antioxidant activity was carried out using the β-carotene test. Methionine and carob seed peels (CSP) extracts (50 and 100 mg/kg) were orally administrated to mice for a week. After administration, behavioral tests were assessed using the Y-maze, elevated plus maze, and forced swimming tests, as well as the novel object recognition task. Furthermore, the oxidative stress status was evaluated by analyzing the levels of the antioxidant enzymes: Superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde levels (MDA). Results: Both extracts exhibited remarkable antioxidant activity and showed antibacterial effect against Gram-positive bacteria tested (Bacillus subtilis and Staphylococcus aureus) and against Pseudomonas aeruginosa (Gram-negative). Therefore, Escherichia coli was very resistant. The behavioral tests proved the efficacy of CSP in enhancing the cognitive impairment of animal models of schizophrenia. Hence, the stated correlation between oxidative stress and schizophrenia was confirmed by the increased SOD and GPx activities and the decreased MDA level. Conclusions: The present study gave further confirmation of the potential correlation between oxidative stress and the development of psychiatric disorders and highlighted the use of natural antioxidants, especially Ceratonia siliqua L. in the improvement of cognitive impairment in the dementia of schizophrenia.

The objective of this study was to perform phytochemical screening, estimate the total phenolics and flavonoids, and to evaluate the antioxidant potential of Tomborissa comorensis fruit. The dried and pulverized fruit of Tomborissa comorensis (150 g) were extracted exhaustively by the Soxhlet method with increasing polarity of solvents (hexane, ethyl acetate, and methanol). Folin–Ciocalteu reagent and aluminum chloride colorimetric methods were used to estimate the total phenolic and flavonoid content of the extracts. Three different methods, namely, 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity, reducing power scavenging activity (FRAP), and total antioxidant capacity, were used to determine in vitro antioxidant activity. Phytochemical screening concerns the presence of flavonoids in the ethyl acetate and methanol extracts and tannins only on the methanol extract. The total phenolic and flavonoid content results show greater dominance in the methanol extract. All tests showed significant dose-dependent antioxidant activities. The ethyl acetate extract shows high activity in DPPH radical scavenging activity, but in a reducing power assay, it is the methanol extract that manifested high activity. The results of this study show that the fruit of T. comorensis is a rich source of phenolic compounds that can play an important role in preventing the progression of many diseases.

Stachys mouretii leaf extracts were analyzed for total phenolic and flavonoid contents. These components are responsible for antioxidant activity. The plant material was collected in April 2018 at the forest of Talasemtane in the region of Ouazzane, Morocco. Dried and crushed leaves were subjected to sequential extraction with hexane, ethyl acetate, and methanol in order of increasing polarity. The amount of total phenolic and flavonoid content were determined with Folin–Ciocalteu and aluminum chloride (AlCl₃) reagents, respectively. For the total phenolic content, gallic acid was used as a standard compound and the results were expressed as µg/mL gallic acid equivalent (GAE), while for the total flavonoids, quercetin was used as a standard compound and the results were expressed as mg/mL quercetin equivalent (QE). The total phenolic content of Stachys mouretii leaf extracts varied from 14.13 to 26.91 µg/mL GAE and the total flavonoid content ranges from 0.04 to 0.08 mg/mL QE. The maximum phenolic and flavonoid contents were found in the ethyl acetate extract. The findings suggested that phytochemicals present in Stachys mouretii are potentially beneficial as therapeutic and antioxidative agents in pharmaceuticals, foods and other related industries.