This research aimed to investigate the chemical composition of seed oils extracted from three Vietnamese Dalbergia species (D. tonkinensis, D. mammosa, and D. entadoides). The fatty acid profiles and contents of tocopherols and sterols of the seed oils, and total phenolic compounds extracted from the fresh seeds were characterized using different methods. Among the examined samples, D. tonkinensis seed oils showed high contents of linoleic acid (64.7%), whereas in D. mammosa, oleic acid (51.2%) was predominant. In addition, α- and γ-tocopherol and β-sitosterol were major ingredients in the seed oils, whereas ferulic acid and rosmarinic acid are usually predominant in the seeds of these species. Regarding sterol composition, the D. entadoides seed oil figured for remarkably high content of Δ5,23-stigmastadienol (1735 mg/kg) and Δ7-stigmastenol (1298 mg/kg). In addition, extracts with methanol/water (80:20, v/v) of seeds displayed significant in vitro antioxidant activity which was determined by DPPH free radical scavenging assay.

Phytochemicals, including flavonoids, stilbenoids, alkaloids, terpenoids, and structurally related synthetic small molecules, exhibit a broad spectrum of beneficial pharmacological effects. These effects stem not only from interactions with specific protein targets but also from their capacity to modify the physical properties of biological membranes. A key membrane property influenced by these plant-derived compounds is the electrical potential drop at the membrane–water interface, which plays a crucial role in numerous cellular processes. Changes in membrane potential impact the function of embedded proteins and ion channels, thereby modulating cell signaling, transport, and pharmacological responses. This review compiles data on how diverse plant and synthetic small molecules alter membrane physical characteristics, particularly the dipole component of the boundary potential in lipid bilayers primarily composed of phosphatidylcholine, a predominant membrane lipid in mammals and fungi. In-depth analysis of structure–activity relationships in this context elucidates how various structural modifications affect the compounds’ ability to shift membrane electrical potential. Understanding these relationships can pinpoint molecular features that drive membrane interactions and facilitate the discovery and design of more potent dipole-modifying agents with therapeutic potential.

Here we elucidated the effects of natural protoberberine alkaloids (rotundine, berberine, and nitidine) and cinnamic acid derivatives (ethyl-4-methoxycinnamate and osthole) found in Vietnamese medicinal plants, on the boundary potential of lipid bilayers and phase behavior of membrane lipids. Lipid bilayers were composed of neutral phosphatidylcholines (PC) and negatively charged phosphatidylserines (PS). Tested compounds did not produce any noticeable changes in the boundary potential with the exception of osthole, which caused a potential drop by about 30 mV independently of the membrane phospholipid composition. Protoberberine alkaloids did not demonstrate an ability to greatly influence phase transition of PC, while they dramatically disturbed PS melting by integrating two different lipid states by merging the low-melting component into the higher one. Ethyl-4-methoxycinnamate and osthole were able to decrease the temperature and sharpness of the PC and PS phase transition, although the effect on PS was higher. We also revealed that ethyl-4-methoxycinnamate and osthole diminished the melting point of both components of PS transition without the changes in their relative impacts. The observed membrane activity of the tested compounds may be related to their physiological and pharmacological potential.