Phytochemistry Reviews最新文献

Indole alkaloids, predominantly found in plants, are a large group of natural product-derived compounds characterized by a remarkable chemical diversity associated with significant biological properties. Among these, terpenoid indole alkaloids are the largest group of secondary metabolites. Tabernaemontana species (Apocynaceae) are widely distributed in tropical and subtropical regions of the world and used in traditional medicine to treat a variety of illnesses, including tumours. These species biosynthesize large quantities of structurally complex monoterpene indole and bisindole alkaloids. Given the compelling biological properties of indole alkaloids, the phytochemical study of Tabernaemontana species has been widely addressed to identify potential anticancer compounds. Several indole alkaloids have shown antiproliferative effect due to different mechanisms, namely by inducing apoptosis or arresting cell cycle, in diverse cancer cell lines, including multidrug-resistant phenotypes. This review primarily aims to underscore the anticancer activity of indole and bisindole alkaloids isolated from several Tabernaemontana species. Moreover, our recent contributions to the field are also highlighted, focusing on the study of Tabernaemontana elegans. The anticancer evaluation, namely the reversion of P-glycoprotein-mediated multidrug resistance, of two sets of monoterpene indole alkaloid derivatives, obtained by modification of some functional groups of two major monoterpene indole alkaloids, is reviewed, as well as the results obtained for a derivative that targeted homologous recombination DNA repair defects.

The challenge of antimicrobial resistance requires new solutions, and Rhodiola sp. is a promising candidate due to its rich medicinal history. This review focuses on Rhodiola sp., especially R. rosea, highlighting its phytochemical constituents, such as salidroside, rosavins, and other phenolics, and their antimicrobial potential. We investigate the efficacy of Rhodiola sp. against various pathogenic bacteria, suggesting their value in combating antimicrobial resistance. Additionally, Rhodiola compounds are being investigated both as direct antimicrobials and as resistance modifiers that increase the efficacy of antibiotics. Rhodiola extracts and salidroside modulate gut microbiota, thereby affecting health and physiological and metabolic disorders. This illustrates the comprehensive therapeutic potential of Rhodiola sp. We emphasize the importance of understanding the complex interactions between Rhodiola phytochemicals, their antimicrobial effects, and their effects on gut microbiota as well as the need for in-depth research. Further studies will be crucial for the development of holistic treatment approaches. Finally, Rhodiola sp. is highlighted as an important natural resource in the fight against microbial pathogens and antibiotic resistance. Research on Rhodiola sp. should continue to further unravel pharmacological and health-promoting potential and thus address an important public health challenge.

The immune system is a complex and fundamental network for organism protection. A minimal unbalance in the host defense system homeostasis can originate severe repercussions in human health. Fundamentally, immune-related diseases can arise from its compromise (immunodeficiency diseases), overactivation against itself (autoimmune diseases) or harmless substances (allergies), and failure of eliminating the harmful agent (chronic inflammation). The notable advances and achievements in the immune system diseases pathophysiology have been allowing for a dramatic improvement of the available treatments. Nevertheless, they present some drawbacks, including the inappropriate benefit/risk ratio. Therefore, there is a strong and urgent need to develop effective therapeutic strategies. Nature is a valuable source of bioactive compounds that can be explored for the development of new drugs. Particularly, plants produce a broad spectrum of secondary metabolites that can be potential prototypes for innovative therapeutic agents. This review describes the immune system and the inflammatory response and examines the current knowledge of eight plants traditionally used as immunomodulatory medicines (Boswellia serrata, Echinacea purpurea, Laurus nobilis, Lavandula angustifolia, Olea europaea, Salvia officinalis, Salvia rosmarinus, and Taraxacum officinale). Moreover, the issues responsible for possible biologic readout inconsistencies (plant species, age, selected organ, developmental stage, growth conditions, geographical location, drying methods, storage conditions, solvent of extraction, and extraction method) will also be discussed. Furthermore, a detailed list of the chemical composition and the immunomodulatory mechanism of action of the bioactive compounds of the selected plant extracts are presented. This review also includes future perspectives and proposes potential new avenues for further investigation.

Polyphenols are a large class of plant specialized metabolites with interesting biological properties. Among them, the stilbene phytoalexins are particularly abundant in grapevine gaining considerable applications in the cosmetic and nutraceutical industry. The well-studied stilbene biosynthetic pathway uses phenylalanine to generate resveratrol, the primary stilbene core synthetized in grapevine. A set of enzymes further metabolize resveratrol producing a diversity of stilbenes with different properties, activities and stabilities. In grapevine, 13 enzymes have been identified with the ability to use resveratrol as a substrate, including ten peroxidases, two glycosyltransferases and one O-methyltransferase. Peroxidases and methyltransferases are the most studied enzymes in grapevine, especially under stress conditions while the role of plant laccases and hydroxylases in stilbene metabolism is still poorly described. This article provides an overview of the key enzymes involved in the synthesis of resveratrol-based derivatives in Vitis spp. Perspectives to identify new enzymes are discussed, which could be further used for stilbene bioproduction using biotechnologies.

In our comprehensive review, we delve into the critical steps of isolation of lutein and zeaxanthin from marigold flowers focusing on several pre-treatment technologies for marigold flower hydrolysis, non-green and green solvent-based extraction techniques of hydrolyzed solid biomass, and saponification of oleoresin while addressing the associated challenges and limitations. The review highlights the varying effects of different pre-treatments on the degradation of pectin, lignin, cellulose, and hemicellulose as well as on lutein and zeaxanthin ester yield. Notably, the enzymatic pre-treatment emerges as the most efficacious approach, despite its reliance on costly commercial enzymes. Based on the literature review, it is determined that supercritical fluid extraction, combined with ultrasound and various co-solvents gives off better yields of lutein as compared to the other extraction methods. This review also covers the saponification, purification, and recovery process. The applications of marigold flowers and lutein are also summarized.

Hydroxycinnamoylamides are specialised metabolites widely distributed in the plant kingdom. These are phenolic moieties covalently linked to mono- or polyamines through amide bonds. Their oxidative coupling (dimerisation) leads to neolignanamides, a group of compounds showing high chemical, structural and functional diversity. Typical to barley, dehydro dimers of hydroxycinnamoylagmatines, hordatines are primarily found in germinated seeds and at the seedling stage. The first step in the biosynthesis of hordatines is catalysed by acyl-coenzyme A-dependent N-hydroxycinnamoyltransferases, and lead to the formation of hydroxycinnamoylagmatines (HCAgms). The oxidative homo- or hetero-dimerisation of the latter results in different hordatines (A, B, C or D). Hordatines can also undergo various types of conjugation and form hydroxylated, methylated or glycosylated derivatives. Although the research on the bioactivities of the hordatines is still nascent, the in planta antifungal properties have long been recognised. While hordatines are naturally and uniquely synthesised in barley plants, these molecules or lead compounds derived therefrom, also exhibit medicinal and pharmaceutical uses important for human health, stimulating research into the utilisation of biotechnology in alternative production hosts and to enhance agricultural yields and value-added production. This review summarises the older and recent knowledge about hordatines and derivatives and may serve as a springboard for future research on this intriguing class of secondary plant metabolites.

Quercus, an essential genus within the Fagaceae family, comprises roughly 500 plant species. Over the past 5 years (2019–2023), there has been a noticeable increase in the production of high-quality research papers focusing on this genus, marking it as an emerging research area of interest. However, despite this growing body of work, there has yet to be a comprehensive and systematic review addressing the metabolites, pharmacological effects, and underlying mechanisms associated with Quercus. To bridge this knowledge gap, the current study performed an exhaustive literature review. A total of 64 relevant papers published in high-impact journals (classified as JCR Q1–Q3) between January 2019 and April 2023 were meticulously selected through comprehensive searches of the ACS, PubMed, Web of Science, and Science Direct databases. The chemical analysis encompassed the identification of 217 compounds, spanning categories like terpenoids, flavonoids, tannins, and phenols, among others. Within this set, 11 previously undisclosed compounds emerged, comprising 6 terpenoids and 5 esters. The study primarily delved into the internal and external pharmacological properties of 23 distinct plant species, including antioxidant, antibacterial, anti-inflammatory, antidiabetic effects, and even the assessment of its potential for mitigating the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This paper offers a comprehensive evaluation of the findings and provides insightful recommendations for guiding future research on this plant genus. The ultimate aim is to facilitate a solid foundation for the modern research and development of Quercus spp., thereby contributing to scientific advancement and enhancing the existing literature in this field.

In Qatar, three main species of Pulicaria (from Asteraceae) such as Pulicaria undulata (L.) C.A.Mey, Pulicaria gnaphalodes (Vent.) Boiss. and Pulicaria sicula (L.) Moris are reported. Traditionally, these species have almost the same ethnomedical uses, including their use as herbal tea. This could be because of morphological similarities among some of these species, which also results in taxonomic ambiguity. Altogether, this indicates that these species need to be reviewed comparatively, to understand the phytochemical uniqueness and therapeutic significance of each species individually, including species differentiation at the subspecies level. Hence, this review aims to comparatively review the available literature about traditional uses, phytochemistry, and bio-activities of these species. Being aromatic plants, the chemical composition of essential oils of these species has been extensively studied and reported over 300 volatile organic compounds. Among these, oxygenated monoterpenes and sesquiterpenes are dominant. The diverse and distinguishable composition of essential oils can differentiate P. undulata and Pulicaria crispa (Forssk.) Oliv. (Synonyme: Pulicaria undulata subsp. undulata). Likewise, flavonoids and sesquiterpenes are the most reported classes of compounds in non-essential oil fractions. Various biological and pharmacological activities are reported to the essential oils, crude extracts, and their fractions, or isolated compounds of these species. Among these, antimicrobial, anticancer, and anti-oxidant activities were mostly investigated, mainly under in vitro conditions. Several distinguishable compounds are listed for each species that can potentially be used as chemical markers while characterizing these species. Most of the traditional claims of these species are validated in recent scientific studies. However, further detailed in vivo clinical interventions are needed for their potential use as therapeutic agents.