Purification and Identification of Flavonoid Molecules from Rosa setate x Rosa rugosa Waste Extracts and Evaluation of Antioxidant, Antiproliferative and Antimicrobial Activities

Optimization of total flavonoids purification process in rose by uniform design method

This study aims to establish a method for purifying total flavonoids in roses using macroporous resin columns, intending to leverage and harness their potential. We screened six macroporous resins to evaluate their capacity for their adsorption and desorption, ultimately identifying X5 macroporous resin as the most effective. To comprehensively understand the adsorption behavior, we analyzed it using various models, such as pseudo-first-order and pseudo-second-order kinetic models, particle diffusion models, and Langmuir, Freundlich, and Temkin isotherm models. Employing both single-factor and uniform design, approaches, the focus of this work was on maximizing the total flavonoid recovery rate. A 3-factor and 10-level uniform design table was utilized for optimizing the optimal process parameters and exploring the antioxidant properties of the purified flavonoids. The optimal process conditions for purifying total flavonoids from roses can be summarized as follows: a sample concentration of 2 mg/mL, pH at 2, 55 mL sample volume, eluent ethanol concentration of 75%, eluent volume of 5 BV, and the elution rate set at 1 mL/min. Following purification, the total flavonoid content peaked at 57.82%, achieving an 84.93% recovery rate, signifying substantial antioxidant potential. Consequently, the method established for purifying TFR using X5 macroporous resin in this study proves to be a dependable and reliable method consistent approach.

A Study of the Chemical Composition and Biological Activity of Michelia macclurei Dandy Heartwood: New Sources of Natural Antioxidants, Enzyme Inhibitors and Bacterial Inhibitors

The wood of Michelia macclurei Dandy (MD) is an excellent material that is widely used in the furniture, handicraft, and construction industries. However, less research has been conducted on the chemical composition and biological activity of heartwood, which is the main valuable part of the wood. This study aimed to investigate the chemical composition and biological activities of the heartwood of Michelia macclurei Dandy (MDHW) and to confirm the active ingredients. Triple quadrupole gas chromatography-mass spectrometry (GC-MS) was used to characterize the volatile components of MDHW, while ultra-performance liquid chromatography-mass spectrometry was used to analyze the non-volatile components (UPLC-MS). The total reducing power, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging assays, acetylcholinesterase and α-glucosidase inhibition assays, and an antimicrobial test of 4 gram bacteria were used to describe the in vitro bioactivities. The GC-MS analysis showed that the volatile components of MDHW were mainly fatty compounds and terpenoids, with sesquiterpenes and their derivatives dominating the terpene composition. β-elemene was the main terpene component in the steam distillation (11.88%) and ultrasonic extraction (8.2%) methods. A total of 67 compounds, comprising 45 alkaloids, 9 flavonoids, 6 lignans, and others, were found by UPLC-MS analysis. The primary structural kinds of the non-volatile components were 35 isoquinoline alkaloids. Alkaloids were the predominant active constituent in all MDHW extracts, including crude extracts, alkaloid fractions, and non-alkaloid fractions. These extracts all demonstrate some biological effects in terms of antioxidant, enzyme inhibition, and bacterial inhibition. The findings of this study show that MDHW is abundant in chemical structure types, has great bioactivity assessment, and has the potential to be used to create natural antioxidants, products that postpone Alzheimer's disease and lower blood sugar levels and antibacterial agents.