A novel 10-hydroxycamptothecin-glucoside from the fruit of Camptotheca acuminata

Polymer lipid hybrid nanoparticles for phytochemical delivery: challenges, progress, and future prospects

Phytochemicals, naturally occurring compounds in plants, possess a wide range of therapeutic properties, including antioxidant, anti-inflammatory, anticancer, and antimicrobial activities. However, their clinical application is often hindered by poor water solubility, low bioavailability, rapid metabolism, and instability under physiological conditions. Polymer lipid hybrid nanoparticles (PLHNPs) have emerged as a novel delivery system that combines the advantages of both polymeric and lipid-based nanoparticles to overcome these challenges. This review explores the potential of PLHNPs to enhance the delivery and efficacy of phytochemicals for biomedical applications. We discuss the obstacles in the conventional delivery of phytochemicals, the fundamental architecture of PLHNPs, and the types of PLHNPs, highlighting their ability to improve encapsulation efficiency, stability, and controlled release of the encapsulated phytochemicals. In addition, the surface modification strategies to improve overall therapeutic efficacy by site-specific delivery of encapsulated phytochemicals are also discussed. Furthermore, we extensively discuss the preclinical studies on phytochemical encapsulated PLHNPs for the management of different diseases. Additionally, we explore the challenges ahead and prospects of PLHNPs regarding their widespread use in clinical settings. Overall, PLHNPs hold strong potential for the effective delivery of phytochemicals for biomedical applications. As per the findings from pre-clinical studies, this may offer a promising strategy for managing various diseases.

Recent Advancement in Chitosan-Based Nanoparticles for Improved Oral Bioavailability and Bioactivity of Phytochemicals: Challenges and Perspectives

The excellent therapeutic potential of a variety of phytochemicals in different diseases has been proven by extensive studies throughout history. However, most phytochemicals are characterized by a high molecular weight, poor aqueous solubility, limited gastrointestinal permeability, extensive pre-systemic metabolism, and poor stability in the harsh gastrointestinal milieu. Therefore, loading of these phytochemicals in biodegradable and biocompatible nanoparticles (NPs) might be an effective approach to improve their bioactivity. Different nanocarrier systems have been developed in recent decades to deliver phytochemicals. Among them, NPs based on chitosan (CS) (CS-NPs), a mucoadhesive, non-toxic, and biodegradable polysaccharide, are considered the best nanoplatform for the oral delivery of phytochemicals. This review highlights the oral delivery of natural products, i.e., phytochemicals, encapsulated in NPs prepared from a natural polymer, i.e., CS, for improved bioavailability and bioactivity. The unique properties of CS for oral delivery such as its mucoadhesiveness, non-toxicity, excellent stability in the harsh environment of the GIT, good solubility in slightly acidic and alkaline conditions, and ability to enhance intestinal permeability are discussed first, and then the outcomes of various phytochemical-loaded CS-NPs after oral administration are discussed in detail. Furthermore, different challenges associated with the oral delivery of phytochemicals with CS-NPs and future directions are also discussed.

The biosynthesis of camptothecin derivatives by Camptotheca acuminata seedlings

10-hydroxycamptothecin and 9-methoxycamptothecin, naturally occurring camptothecin derivatives, are reportedly present in Camptotheca acuminata with a powerful cytotoxic effect and strong antitumor activity. In this paper, we studied the derivatization reaction of camptothecin catalyzed by C. acuminata seedlings. HPLC traced the reaction between exogenous camptothecin and C. acuminata seedlings. The results showed that the exogenous camptothecin was converted into 10-hydroxycamptothecin and 9-methoxycamptothecin by the tender roots and stems of C. acuminata seedlings, which would be a new method for the synthesis of two camptothecin derivatives.

Possible clues for camptothecin biosynthesis from the metabolites in camptothecin-producing plants

The plant derived camptothecin (CPT) is a pentacyclic pyrroloquinoline alkaloid with unique antitumor activity. Successive discoveries of new CPT-producing plants occurred in recent years due to market demands. The scattered distribution among angiosperms drew researchers' attention. The aim of this review is to appraise the literature available to date for CPT distribution and the phytochemistry of these CPT-producing plants. Metabolite comparative analyses between the plants were also conducted for tracking of possible clues for CPT biosynthesis. Forty-three plant species in total were reported to possess CPT-producing capability, and one hundred twenty-five alkaloids classified into three major categories are summarized herein. Metabolite comparative analysis between these plants suggests the probability that the formation of the central intermediate for CPT biosynthesis has multiple origins. A more complete biogenetic reasoning for CPT and its structural homolog was delineated based on this fragmentary phytochemical evidence from a chemical point of view. Furthermore, an in-house compound database was constructed for further metabolomic analysis.

Triterpenes from the fruit of Camptotheca acuminata suppress human hepatocellular carcinoma cell proliferation through apoptosis induction

The fruit of Camptotheca acuminata, a kind of mainly medicinal plant, possesses good antitumor properties. In order to explore the bioactive compounds for the treatment of hepatocellular carcinoma, the study focused on the isolation of cytotoxic compounds from the fruit of Camptotheca acuminata, which led to the discovery of fourteen compounds, including one new triterpene, 3β,20-dihydroxy-30α-methyl,17(29)-β-epoxy-28-norlupane (1), together with thirteen known compounds (2-14). The structures of isolated compounds were demonstrated by spectroscopic methods including 1D and 2D NMR spectroscopy. Moreover, all triterpenes were evaluated for antiproliferative activities against two human hepatocellular carcinoma cell lines, HepG2 and Hep3B. Compound 3 showed the strongest cytotoxic activity against the HepG2 with IC₅₀ value at 29.6 μM. Further study demonstrated that compound 3 exhibited cytotoxic activity through the induction of apoptosis.