Comparison of the respiratory effects of commonly utilized general anaesthesia regimes in male Sprague-Dawley rats.

Background: Respiratory parameters in experimental animals are often characterised under general anaesthesia. However, anaesthesia regimes may alter the functional and mechanical properties of the respiratory system. While most anaesthesia regimes have been shown to affect the respiratory system, the effects of general anaesthesia protocols commonly used in animal models on lung function have not been systematically compared. Methods: The present study comprised 40 male Sprague-Dawley rats divided into five groups (N = 8 in each) according to anaesthesia regime applied: intravenous (iv) Na-pentobarbital, intraperitoneal (ip) ketamine-xylazine, iv propofol-fentanyl, inhaled sevoflurane, and ip urethane. All drugs were administered at commonly used doses. End-expiratory lung volume (EELV), airway resistance (Raw) and tissue mechanics were measured in addition to arterial blood gas parameters during mechanical ventilation while maintaining positive end-expiratory pressure (PEEP) values of 0, 3, and 6 cm H2O. Respiratory mechanics were also measured during iv methacholine (MCh) challenges to assess bronchial responsiveness. Results: While PEEP influenced baseline respiratory mechanics, EELV and blood gas parameters (p < 0.001), no between-group differences were observed (p > 0.10). Conversely, significantly lower doses of MCh were required to achieve the same elevation in Raw under ketamine-xylazine anaesthesia compared to the other groups. Conclusion: In the most frequent rodent model of respiratory disorders, no differences in baseline respiratory mechanics or function were observed between commonly used anaesthesia regimes. Bronchial hyperresponsiveness in response to ketamine-xylazine anaesthesia should be considered when designing experiments using this regime. The findings of the present study indicate commonly used anaesthetic regimes allow fair comparison of respiratory mechanics in experimental animals undergoing any of the examined anaesthesia protocols.

Bioactive metabolite profile and antioxidant properties of brown juice, a processed alfalfa (Medicago sativa) by-product.

Recently, leaf protein concentrate (LPC) has gained increased attention in response to the constantly growing protein demand. Green biorefineries can become more economical by valorizing their by-products and reducing environmental risks. The current study describes the variations in the antioxidant capacity and phytochemical composition of a liquid by-product (referred to as brown juice (BJ)) obtained during the extraction of leaf protein concentrate (LPC) from the fresh biomass of alfalfa (Medicago sativa L.). Four varieties of alfalfa were investigated during three harvest times, i.e., August 2017 (first harvest), September 2017 (second harvest), and June 2018 (third harvest). Also, the fresh BJ was lacto-fermented to extend its preservation period but also modifying its composition. The results of different general phytochemical composition analyses and antioxidant assays revealed similar tendencies across different alfalfa varieties and harvest times. Most of the phytochemicals in the BJ identified by HPLC-MS/MS can be classified as flavonoids/flavonoid derivatives, e.g., apigenin, naringenin, luteolin, formononetin. Substantially, the lacto-fermentation process induced a switch into aglycones, e.g., apigenin content increased by an order of magnitude, while apigenin-7-O-glucuronide content was halved after lacto-fermentation. Additionally, several B vitamins were detected, including B2, B3, and B7. These results could provide a basis for various ways of industrial valorization but need to be strengthened by data generated from large-scale production.

Raw and Fermented Alfalfa Brown Juice Induces Changes in the Germination and Development of French Marigold (Tagetes patula L.) Plants.

Organic and ecological farming programs require new and efficient biostimulants with beneficial properties for the sustainable and safe production of seedlings and ornamental plants. We examined the effect of non-fermented and lacto-fermented alfalfa brown juice (BJ) on seed germination and the vegetative, physiological, and anatomical properties of French marigold (Tagetes patula L. 'Csemo') plants which were treated with 0.5-10% fermented and non-fermented BJ, with tap water applied as a control. Applying 0.5% fermented BJ significantly improved seed germination compared with non-fermented BJ, resulting in an increase of 9.6, 11.2, 10.9, and 41.7% in the final germination percent, germination rate index, germination index, and vigor index, respectively. In addition, it increased the root and shoot length by 7.9 and 16.1%, respectively, root and shoot dry mass by 20 and 47.6%, respectively, and the number of leaves by 28.8% compared to the control. Furthermore, an increase in contents of water-soluble phenol, chlorophyll a and b, and carotenoid was reported upon the application of 0.5% fermented BJ, while peroxidase activity decreased. Our results prove that alfalfa BJ can be enrolled as a biostimulant as part of the circular farming approach which supports the sustainable horticultural practice.