Characterization of Forage Quality, Phenolic Profiles, and Antioxidant Activity in Alfalfa (Medicago sativa L.)

Abstract

Alfalfa (Medicago sativa L.) is one of the most important forage species and is recently more in focus for human consumption mainly due to its content of bioactive phenolics. Samples of the seventeen alfalfa cultivars/populations were collected at the Agricultural Institute Osijek with the aim to evaluate their forage quality, phenolic profiles, and antioxidant potential. Significant differences (p < 0.05) existed among studied alfalfa in all analyzed traits. The cultivar OS 99 and populations L7 and L20 were characterized by high crude protein content (22.5–24.7%) and the lowest neutral (40.2–42.9%) and acid detergent fibres (33–35.5%). The soluble-free phenolics from alfalfa leaves were extracted by methanol while insoluble cell-wall bound phenolics were released by alkaline hydrolysis. The bound phenolic extract showed a stronger DPPH scavenging capacity (20.8 mg TE/g dm) than the soluble (11.4 mg TE/g dm). The HPLC data revealed that more phenolics were found in the bound (3638.0 μg/g dm) than in the soluble form (912.3 μg/g dm). In the soluble extract of the alfalfa leaves, the major compound was catechin (338.3 μg/g dm), while rutin, epicatechin, and ferulic acid were minor ones. In the bound phenolic extract, the most abundant was ferulic (2198.2 μg/g dm) and p-coumaric acid (983.7 μg/g dm), followed by myricetin, apigenin, and quercetin. The principal component analysis revealed that alfalfa cultivars/populations were better discriminated based on the data on phenolics, rather than on forage quality. The cultivars/populations Florida 66, OS 66, L 40, L 42, Seed Force 4, and Torlesse were the most interesting in terms of phenolic health-promoting characteristics.

The effect of diet composition on the diversity of active gut bacteria and on the growth of Spodoptera exigua (Lepidoptera: Noctuidae)

“…These include detoxification of plant defense chemicals ( Cile et al 2001 ); its presence in the gut of the gypsy moth is linked to tolerance of diets with high levels of monoterpenes ( Powell and Raffa 1999 , Broderick et al 2004 ). Alfalfa diet used in this study contained minimally processed recalcitrant plant materials which are rich in a variety of anti-herbivory phenolic compounds ( Horvat et al 2022 ), leading us to hypothesize that S. exigua larvae consuming this diet may benefit from harboring detoxifying symbionts. Furthermore, Rhodococcus has been implicated in other roles such as B-vitamin synthesis for diet supplementation in kissing bugs ( Gilliland et al 2023 ) and in pesticide degradation, where Rhodococcus isolates from Helicoverpa armigera degraded up to 43% chlorpyriphos insecticide, a potential factor in the pest’s resistance to insecticides ( Madhusudan et al 2021 ).…”

Validations of sensory overall acceptability optimizations on response surface methodology through just-about-right technique for coffee-leaf tea at different brewing methods

“…0.1 mL of each tea extract was combined with 10 mL of chloroform and transferred onto a quartz cuvette. The absorbance at a wavelength of 275.8 nm was recorded (Horvat et al, 2022).…”

The Role of Potential Oxidative Biomarkers in the Prognosis of Acute Ischemic Stroke and the Exploration of Antioxidants as Possible Preventive and Treatment Options

“…These were all shown to exhibit positive effects in acute ischemic stroke animal models by mostly interacting with the oxidative stress pathways [ 207 ]. Similarly, Medicago sativa extract was found to improve antioxidant enzymes (SOD and GPx) and anti-inflammatory cytokines (TNFa and IL1) activities due to its increased content of phenols, flavonoids, isoflavones, phytoestrogens, and vitamin C [ 207 , 208 , 209 ].…”