Effects of poplar buds as an alternative to propolis on postharvest diseases control of strawberry fruits

Galangin: A Promising Flavonoid for the Treatment of Rheumatoid Arthritis-Mechanisms, Evidence, and Therapeutic Potential

Rheumatoid Arthritis (RA) is a chronic autoimmune disease characterized by progressive joint inflammation and damage. Oxidative stress plays a critical role in the onset and progression of RA, significantly contributing to the disease's symptoms. The complex nature of RA and the role of oxidative stress make it particularly challenging to treat effectively. This article presents a comprehensive review of RA's development, progression, and the emergence of novel treatments, introducing Galangin (GAL), a natural flavonoid compound sourced from various plants, as a promising candidate. The bioactive properties of GAL, including its anti-inflammatory, antioxidant, and immunomodulatory effects, are discussed in detail. The review elucidates GAL's mechanisms of action, focusing on its interactions with key targets such as inflammatory cytokines (e.g., TNF-α, IL-6), enzymes (e.g., SOD, MMPs), and signaling pathways (e.g., NF-κB, MAPK), which impact inflammatory responses, immune cell activation, and joint damage. The review also addresses the lack of comprehensive understanding of potential treatment options for RA, particularly in relation to the role of GAL as a therapeutic candidate. It highlights the need for further research and clinical studies to ascertain the effectiveness of GAL in RA treatment and to elucidate its mechanisms of action. Overall, this review provides valuable insights into the potential of GAL as a therapeutic option for RA, shedding light on its multifaceted pharmacological properties and mechanisms of action, while suggesting avenues for future research and clinical applications.

Inorganic Element Determination of Romanian Populus nigra L. Buds Extract and In Vitro Antiproliferative and Pro-Apoptotic Evaluation on A549 Human Lung Cancer Cell Line

Populus nigra L. is a plant from Salicaceae family, native in Europe. Many parts of this tree can be used as active ingredients, but the most valuable are the buds. In recent years, a growing number of studies reported their activity in the development of a wide range of pharmacological activities including diabetes, cardiovascular diseases, and cancer. The aim of this study was to determine the phytochemical composition and to evaluate the inorganic elements’ concentration as well as the in vitro antiproliferative and pro-apoptotic potential of a Populus nigra L. buds extract collected from Timișoara (Romania) against A549 human lung cancer cell line. Populus nigra L. bud extract was found to contain twelve different phenolic compounds. The inorganic elements concentrations were below the limit of detection for Co, Pb, and As, whereas Cu = 6.66 µg/g; Cr = 0.79 µg/g; Ni = 3.28 µg/g; Fe = 39.00 µg/g; Zn = 14.84 µg/g; Mn = 0.59 µg/g; Al = 2109.87 µg/g; and Cd = 0.019 µg/g. The extract was tested for the in vitro antiproliferative and pro-apoptotic potential on A549 human lung cancer cell line using different concentrations, namely 10, 25, 50, 75, 100, and 150 μg/mL. Results have shown that poplar bud extract induced a significant decrease of tumor cell viability in a dose-dependent manner with an IC₅₀ = 72.49 μg/mL and blocked the cells in the G0/G1 phase of the cell cycle. Phenomena of early apoptosis (from 1.34 ± 0.33% control cells to 2.68 ± 0.62% at 150 µg/mL) and late apoptosis (from 1.43 ± 0.14% control cells to 5.15 ± 1.02% at 150 µg/mL) were detected by Annexin V-PI double staining. Poplar bud extract can be regarded as a promising candidate for future studies involving lung cancer.

Pinocembrin-7-Glucoside (P7G) Reduced Postharvest Blue Mold of Navel Orange by Suppressing Penicillium italicum Growth

The current study aimed to examine the in vitro and in vivo antifungal potential of pinocembrin-7-glucoside (P7G). P7G is an antifungal flavanone glycoside isolated from Ficus hirta Vahl. fruit against Penicillium italicum, a causative pathogen of blue mold disease in citrus fruit, and this study elucidates its possible action mechanism. P7G had a prominent mycelial growth inhibitory activity against P. italicum, with an observed half maximal effective concentration, minimum inhibitory concentration and minimum fungicidal concentration of 0.08, 0.2, and 0.8 g/L, respectively. The data from the in vivo test show that P7G significantly reduced blue mold symptoms and disease development of P. italicum in artificially inoculated "Newhall" navel orange. Compared to the control, increases in the cell membrane permeability of P. italicum supernatant and decreases in the intracellular constituent (e.g., soluble protein, reducing sugar, and total lipid) contents of P. italicum mycelia were identified, supporting scanning electron microscopy and transmission electron microscopy observations. Furthermore, a marked decline in both chitin and glucanase contents of P. italicum mycelia treated with P7G was induced by increasing its related degrading enzyme activities, suggesting that the cell wall structure was destroyed. The current study indicated that P7G may be a novel alternative for reducing blue mold by suppressing mycelial growth of P. italicum via a cell membrane/wall-targeting mechanism.

Laccase-Mediated Enhancement of the Antioxidant Activity of Propolis and Poplar Bud Exudates

The treatment of propolis and poplar bud exudates with laccase from Trametes versicolor and 2,2,6,6-tetramethyl-1-piperidinyloxy free radical increased the antioxidant activity, as evaluated by the 2,2'-diphenyl picrylhydrazyl (DPPH)- and t-butyl-OOH-induced DNA breakage comet assay analyses. The effect was highest for shorter reaction times. Propolis showed the highest antioxidant activity in the DPPH test, whereas poplar bud exudates were more active in reducing the t-butyl-OOH-induced lesions in the Chinese hamster ovary cell line. Even if the concentration of polyphenols decreased during the oxidation, the formation of low-molecular-weight phenols phloroglucinol 4 (1,3,5-trihydroxy benzene), hydroquinone 5 (1,4-dihydroxy benzene), and catechol 6 (1,2-dihydroxy benzene), characterized by the radical-scavenging activity, can account for the observed increase in the antioxidant activity.