In recent decades, a lot of attention has been paid to Cannabis sativa L. due to its useful applications, including in fibers, oil, food for humans and animals, and therapeutics. The present study aimed to determine antioxidant activity of cannabinoids in Cannabis sativa L. in vivo, evaluating the possible antioxidative effect of Cannabis sativa L. extract (CE) on malondialdehyde (MDA) and glutathione (GSH) concentrations as well as on catalase (CAT) activity in BALB/c mice. In total, 40 mice were divided into five equal groups: the aluminum group (7.5 mg AlCl₃/kg/d (0.15 LD₅₀), the saline group, the 10% ethanol group (an appropriate amount of the solution for mouse weight), the CE group (1.6 mg CE/g/day), and the aluminum-CE group (7.5 mg AlCl₃ plus 1.6 mg CE/g/day). The results of the study showed that CE significantly decreased (by 26.81%, p < 0.05) the concentration of GSH in blood of the mice and the concentration of MDA in the brain (by 82.12%) and liver (by 53.5%) of the mice compared to the respective concentrations in the AlCl₃ group. CE significantly (p < 0.05) increased CAT activity in the brain (by 64.79%) and liver (by 72.37%) of the mice after the AlCl₃-induced prooxidant effect. The results showed the antioxidant activity of cannabidiolic acid (CBDA) in vitro. The findings in vivo indicate that Cannabis sativa L. is a good source of natural antioxidants and can be used in the management of oxidative stress.

In the present study, the effects of Origanum onites L. extract and essential oil of O. onites L. on the antioxidant status of the liver and brain of mice were investigated. Due to certain disadvantages of essential oils, such as poor solubility, high volatility and sensitivity to UV light and heat, formulation of liposomes with Oregano essentials (OE) was optimized and used in this study. The results demonstrated that the best composition of the lipid carriers and OE were conducted in terms of the polydispersity index (PDI), mean particle size and encapsulation efficiency (EE). For further study the LE4 formulation was used, which contained Lipoid S100 at 45 mg, Lipoid S75 at 45 mg and 90 mg of EO. The administration of O. onites L. extract to mice for 21 days significantly decreased the glutathione (GSH) level in the livers and brains of the mice as well as the malondialdehyde (MDA) concentration in the livers. In the brains of the mice, MDA level significantly increased after this extract consumption. Whereas liposomes with OE significantly decreased GSH concentration in the mouse brain and MDA concentration in the mouse liver, there was an increased (p > 0.05) GSH level in the liver and MDA concentration in the brain of mice compared with the control group. It was found that both O. onites. ethanolic extract as well as liposomes with OE of this plant material affect the antioxidant status in the livers and brains of mice.

Cannabis is one of the oldest plants on earth, which is known and used for medical purposes. There are many articles on hempseed oil research in the scientific databases, while the antioxidant activity of Cannabis sativa L. herb extracts has not been extensively studied yet, to our knowledge. In the present study, antioxidant properties of different Cannabis sativa L. varieties from different regions of Lithuania were examined. Spectrophotometric FRAP (ferric reducing antioxidant power) and CUPRAC (cupric reducing antioxidant capacity) methods were used for determination. It was found that Cannabis sativa L. herb extracts possess antioxidant activity. The strongest antioxidant activity was evaluated in the Futura variety and the lowest in Manoica. The obtained results showed that a statistically significant (p ˂ 0.05) higher reductive power was determined by analysing the raw material by the spectrophotometric FRAP method. According to the hemp growth location in Lithuania, the highest TEAC values were estimated in the samples from the North region.

In the present study the effects of Origanum onites L. extract and essential oil of O. onites L. on the antioxidant status of the liver and brain of mice were investigated. Due to certain disadvantages of essential oils, such as poor solubility, high volatility, sensitivity to UV light and heat, formulation of liposomes with Oregano essentials (OE) was optimized and used in this study. The results demonstrated that the best composition of the lipid carriers and Oregano essentials were conducted in terms of the PDI, mean particle size and EE. The LE4 formulation contained Lipoid S100 of 45 mg, Lipoid S75 of 45 mg and 90 mg of EO. The administration of O. onites L. extract to mice for 21 days significantly decreased glutathione (GSH) level in the liver and brain of mouse as well as malondialdehyde (MDA) concentration in the liver. In the brain of mice MDA level significantly increased after this extract consumption. Whereas liposomes with OE significantly decreased GSH concentration in mouse brain and MDA concentration in mouse liver but increased (p>0.05) GSH level in liver and MDA concentration in brain of mice compared with the control group. It was investigated that both, O. onites L. extract as well as liposomes with OE of this plant material make changes in the antioxidant status in the liver and brain of mice.

The aim of the present work was to improve and validate the HPLC-CUPRAC postcolumn method for the evaluation of active antioxidant markers from the acetonic extracts ofGinkgo bilobaleaves. Improvement of the HPLC online assay was performed by evaluating the suitable loop temperature, the reaction loop length, and the impact of flow rate. Separation of the analytes was performed by the HPLC method on an ACE C18 analytical column using a gradient elution program. The separated antioxidant markers in the extracts reacted with copper(II)-neocuproine (Cu(II)-Nc) reagent in the postcolumn reaction coil. The reagent was reduced by antioxidants to the copper(I)-neocuproine (Cu(I)-Nc) chelate with a maximum absorption at 450 nm. Validation experiments confirmed sufficient precision, sensitivity, and effectiveness of the corresponding method, which could be used for further evaluations of active antioxidant compounds in similar plant materials.

Walnut septum (WS), a major by-product of walnut processing, represents a promising source of bioactive compounds with potential antioxidant and antimicrobial properties. This study aimed to characterise the phytochemical composition of WS extracts from different habitat origins and evaluate their antimicrobial activity. Total amino acids were profiled by gas chromatography–mass spectrometry, while phenolic compounds were analysed using high-performance liquid chromatography. Both methods were evaluated according to ICH Q2 (R2) guidelines for analytical procedure validation. The results showed a complex composition of amino acids and polyphenols, including ellagic acid and quercitrin. However, it was clear that habitat variations in WS samples had a significant impact on the quantities and composition of phenolic compounds and total amino acids in WS extracts. Antimicrobial activity was assessed against Gram-positive and Gram-negative bacterial strains. Variations in antimicrobial efficacy were associated with differences in phenolic composition and content due to habitat differences in WS sample origins. Collectively, this study highlights the WS as a valuable agro-industrial by-product with potential applications as a natural source of antimicrobial compounds in food and pharmaceutical systems.