Transformation and Characterization of Δ12-Fatty Acid Acetylenase and Δ12-Oleate Desaturase Potentially Involved in the Polyacetylene Biosynthetic Pathway from Bidens pilosa

Disafynol: A polyacetylene dimer from Centaurea schmidii enhancing breast cancer cell apoptosis via oxidative and ER stress pathways

Phytochemical analysis of the aerial parts of Centaurea schmidii Wagenitz (Asteraceae) led to the isolation of disafynol, a novel polyacetylene, for the first time. This study investigated its anti-cancer effects and the mechanisms underlying these effects in MDA-MB-231 (estrogen receptor-negative) and MCF-7 (estrogen receptor-positive) breast cancer cell lines. The cytotoxic effects of disafynol were evaluated using various concentrations to measure cell viability, apoptosis, reactive oxygen species (ROS) levels, mitochondrial membrane potential (MMP), caspases-12/6 activity, and protein aggregation. Expression of apoptotic markers and endoplasmic reticulum (ER) stress-related genes was analyzed by western blot and reverse transcription-PCR analyses, respectively. Disafynol exhibited dose-dependent cytotoxicity, with greater potency in MDA-MB-231 cells (IC50: 10.6 µM) compared to MCF-7 cells (IC50: 30 µM), indicating hormone receptor-independent manner of cell growth inhibition. Treating cells with disafynol caused significant apoptosis, marked by enhanced ROS production and reduced MMP. Meanwhile, disafynol induced Bcl-2 downregulation, Bax upregulation, and caspase-12/6 activities in both breast cancer cells. Additionally, disafynol triggered ER stress, as evidenced by protein aggregation and upregulation of genes related to ER stress, including BIP, ATF4, CHOP, and XBP-1. Overall, disafynol demonstrates significant pro-apoptotic effects on breast cancer cells by inducing oxidative stress and activating the ER stress pathway. Its hormone receptor-independent cytotoxicity suggests potential therapeutic applications for treating breast cancers, including triple-negative subtypes.

Variation on a theme: the structures and biosynthesis of specialized fatty acid natural products in plants

Plants are able to construct lineage-specific natural products from a wide array of their core metabolic pathways. Considerable progress has been made toward documenting and understanding, for example, phenylpropanoid natural products derived from phosphoenolpyruvate via the shikimate pathway, terpenoid compounds built using isopentyl pyrophosphate, and alkaloids generated by the extensive modification of amino acids. By comparison, natural products derived from fatty acids have received little attention, except for unusual fatty acids in seed oils and jasmonate-like oxylipins. However, scattered but numerous reports show that plants are able to generate many structurally diverse compounds from fatty acids, including some with highly elaborate and unique structural features that have novel bioproduct functionalities. Furthermore, although recent work has shed light on multiple new fatty acid natural product biosynthesis pathways and products in diverse plant species, these discoveries have not been reviewed. The aims of this work, therefore, are to (i) review and systematize our current knowledge of the structures and biosynthesis of fatty acid-derived natural products that are not seed oils or jasmonate-type oxylipins, specifically, polyacetylenic, very-long-chain, and aromatic fatty acid-derived natural products, and (ii) suggest priorities for future investigative steps that will bring our knowledge of fatty acid-derived natural products closer to the levels of knowledge that we have attained for other phytochemical classes.

Comparative Analysis and Structural Modeling of Elaeis oleifera FAD2, a Fatty Acid Desaturase Involved in Unsaturated Fatty Acid Composition of American Oil Palm

American oil palm (Elaeis oleifera) is an important source of dietary oil that could fulfill the increasing worldwide demand for cooking oil. Therefore, improving its production is crucial and could be realized through breeding and genetic engineering approaches aiming to obtain high-yielding varieties with improved oil content and quality. The fatty acid composition and particularly the oleic/linoleic acid ratio are major factors influencing oil quality. Our work focused on a fatty acid desaturase (FAD) enzyme involved in the desaturation and conversion of oleic acid to linoleic acid. Following the in silico identification and annotation of Elaeis oleifera FAD2, its molecular and structural features characterization was performed to better understand the mechanistic bases of its enzymatic activity. EoFAD2 is 1173 nucleotides long and encodes a protein of 390 amino acids that shares similarities with other FADs. Interestingly, the phylogenetic study showed three distinguished groups where EoFAD2 clustered among monocotyledonous taxa. EoFAD2 is a membrane-bound protein with five transmembrane domains presumably located in the endoplasmic reticulum. The homodimer organization model of EoFAD2 enzyme and substrates and respective substrate-binding residues were predicted and described. Moreover, the comparison between 24 FAD2 sequences from different species generated two interesting single-nucleotide polymorphisms (SNPs) associated with the oleic/linoleic acid contents.

Analysis of Lipophilic Antioxidants in the Leaves of Kaempferia parviflora Wall. Ex Baker Using LC-MRM-MS and GC-FID/MS

Lipophilic metabolites such as carotenoids, fatty acids, vitamin K1, phytosterols, and tocopherols are important antioxidants that are used in the cosmetics, foods, and nutraceutical industries. Recently, there has been a growing demand for the use of byproducts (wastes) as a potential source of industrially important compounds. The leaves of Kaempferia parviflora (black ginger) (KP-BG) are major byproducts of KP-BG cultivation and have been reported to contain several bioactive metabolites; however, the composition of lipophilic metabolites in KP-BG leaves has not been examined. In this study, the lipophilic antioxidant profile was analyzed in the leaves of KP-BG plants grown in vitro and ex vitro. Lipophilic compounds, namely carotenoids (80.40-93.84 µg/g fresh weight (FW)), tocopherols (42.23-46.22 µg/g FW), phytosterols (37.69-44.40 µg/g FW), and vitamin K1 (7.25-7.31 µg/g FW), were quantified using LC-MRM-MS. The fatty acid profile of the KP-BG leaves was identified using GC-FID/MS. The content of individual lipophilic compounds varied among the KP-BG leaves. Ex vitro KP-BG leaves had high levels of lutein (44.38 µg/g FW), α-carotene (14.79 µg/g FW), neoxanthin (12.30 µg/g FW), β-carotene (11.33 µg/g FW), violaxanthin (11.03 µg/g FW), α-tocopherol (39.70 µg/g FW), α-linolenic acid (43.12%), palmitic acid (23.78%), oleic acid (12.28%), palmitoleic acid (3.64%), total carotenoids (93.84 µg/g FW), and tocopherols (46.22 µg/g FW) compared with in vitro KP-BG leaves. These results indicate that ex-vitro-grown KP-BG leaves could be used as a valuable natural source for extracting important lipophilic antioxidants.