Metabolomic Profile and Cytotoxic Activity of Cissus incisa Leaves Extracts

Cissus incisa leaves have been traditionally used in Mexican traditional medicine to treat certain cancerous illness. This study explored the metabolomic profile of this species using untargeted technique. Likewise, it determined the cytotoxic activity and interpreted all data by computational tools. The metabolomic profile was developed through UHPLC-QTOF-MS/MS for dereplication purposes. MetaboAnalyst database was used in metabolic pathway analysis and the network topological analysis. Hexane, chloroform/methanol, and aqueous extracts were evaluated on HepG2, Hep3B, HeLa, PC3, A549, and MCF7 cancer cell lines and IHH immortalized hepatic cells, using Cell Titer proliferation assay kit. Hexane extract was the most active against Hep3B (IC50 = 27 ± 3 μg/mL), while CHCl3/MeOH extract was the most selective (SI = 2.77) on the same cell line. A Principal Component Analysis (PCA) showed similar profiles between the extracts, while a Venn diagram revealed 80 coincident metabolites between the bioactive extracts. The sesquiterpenoid and triterpenoid biosynthesis pathway was the most significant identified. The Network Pharmacology (NP) approach revealed several targets for presqualene diphosphate, phytol, stearic acid, δ-tocopherol, ursolic acid and γ-linolenic acid, involved in cellular processes such as apoptosis. This work highlights the integration of untargeted metabolomic profile and cytotoxic activity to explore plant extracts, and the NP approach to interpreting the experimental results.

Bioassay-Guided Identification of the Antiproliferative Compounds of Cissus trifoliata and the Transcriptomic Effect of Resveratrol in Prostate Cancer Pc3 Cells

The bioassay-guided fractionation of a CHCl₃-MeOH extract from the stems of Cissus trifoliata identified an active fraction against PC3 prostate cancer cells. The treatment for 24 h showed an 80% reduction in cell viability (p ≤ 0.05) by a WST-1 assay at a concentration of 100 μg/mL. The HPLC-QTOF-MS analysis of the fraction showed the presence of coumaric and isoferulic acids, apigenin, kaempferol, chrysoeriol, naringenin, ursolic and betulinic acids, hexadecadienoic and octadecadienoic fatty acids, and the stilbene resveratrol. The exposure of PC3 cells to resveratrol (IC₂₅ = 23 μg/mL) for 24 h induced significant changes in 847 genes (Z-score ≥ ±2). The functional classification tool of the DAVID v6.8 platform indicates that the underlying molecular mechanisms against the proliferation of PC3 cells were associated (p ≤ 0.05) with the process of differentiation and metabolism. These findings provide experimental evidence suggesting the potential of C. trifoliata as a promising natural source of anticancer compounds.

Antibacterial Activity of Cissus incisa Extracts against Multidrug- Resistant Bacteria

Aims:

The need to find new antimicrobial agents to cope with this phenomenon increases.

Background:

Infection diseases are illness caused by different microorganisms, such as bacteria, among those caused by resistant bacteria are associated with greater morbidity, mortality and cost of the treatment than those caused by sensitive bacteria of the same species.

Objective:

Need to find new antimicrobial agents to cope with this phenomenon increases.

Method:

This work carried out the study of biological activities of Cissus incisa, taking account its traditional use. Three extracts were prepared from the leaves of this plant: hexane, chloroform methanol (1:1) and aqueous. Their antibacterial and antitubercular activities were evaluated using microdilution and alamar blue assays; respectively.

Result:

The chloroform/methanol extract (1:1) was the most active of the three tested extracts for antimicrobial activity. In this way, the extract exhibits a broad spectrum of antimicrobial activity, against the Gram positive and Gram negative bacteria tested, with MIC values between 125 to 500 μg/mL.

Conclusion:

This research contributes both to the knowledge of the Mexican flora, as well as the discovery of potential antibacterial agents derivate from plants.

Evaluation of Some Plant-derived Secondary Metabolites Against Sensitive and Multidrug-resistant Mycobacterium tuberculosis

The results on the bioevaluation of thirty five plant-derived secondary metabolites against one sensitive and three multidrugresistant clinical isolates of Mycobacterium tuberculosis are reported. Results toward the sensitive strain showed that five products gave MIC values of 12.5 µg/mL: the alkaloids 6-methoxydihydrochelerytrine (2) and 6-methoxy-dihydrochelirubine (6), the flavanone pinostrobin (17), 1-hydroxy-benzoisochromanquinone (23) and 23-hydroxy-5a-lanosta7,9(11),24-triene-3-one (33). These were followed by the peracetylstrictosidine lactam (12) and the quinone aloe-emodin (24) which displayed MICs of 6.25 µg/mL. Finally, liriodenine (8) was the most active (MIC: 3.125 µg/mL) of all secondary metabolites. Results with the multidrug-resistant clinical isolates showed that 6-methoxy-dihydrochelirubine (6) was the most active (MIC: 12.5 µg/mL).

Nuclear magnetic resonance spectroscopy data of isolated compounds from Acacia farnesiana (L) Willd fruits and two esterified derivatives

In the present article we describe the spectroscopic data of ¹H and ¹³C Nuclear Magnetic Resonance of 11 compounds including: Nine natural products from the hexanic-chloroformic and methanolic extracts of Acacia farnesiana fruit and two esterified derivatives (22E-stimasta-5,22-dien- 3β-acetyl and methyl 3,4,5-triacetyloxybenzoate). Data linked to the research work entitled "Chemical composition of fruits of Acacia farnesiana (L) Willd and its activity against Mycobacterium tuberculosis and dysentery bacteria" (Hernández et al., 2019) [1].

Potential Mechanism of Action of 3'-Demethoxy-6-O-demethyl-isoguaiacin on Methicillin Resistant Staphylococcus aureus

Bacterial infections represent one of the main threats to global public health. One of the major causative agents associated with high morbidity and mortality infections in hospitals worldwide is methicillin-resistant Staphylococcus aureus. Therefore, there is a need to develop new antibacterial agents to treat these infections, and natural products are a rich source of them. In previous studies, we reported that lignan 3'-demethoxy-6-O-demethylisoguaiacin, isolated and characterized from Larrea tridentate, showed the best activity towards methicillin-resistant S. aureus. Thus, the aim of this study was to determine the potential molecular mechanism of the antibacterial activity of 3'-demethoxy-6-O-demethylisoguaiacin against methicillin-resistant S. aureus using microarray technology. Results of microarray genome expression were validated by real-time polymerase chain reaction (RT-PCR). The genetic profile expression results showed that lignan 3'-demethoxy-6-O-demethylisoguaiacin had activity on cell membrane affecting proteins of the ATP-binding cassette (ABC) transport system causing bacteria death. This molecular mechanism is not present in any antibacterial commercial drug and could be a new target for the development of novel antibacterial agents.

Potential mechanism of action of meso-dihydroguaiaretic acid on Mycobacterium tuberculosis H37Rv

The isolation and characterization of the lignan meso-dihydroguaiaretic acid (MDGA) from Larrea tridentata and its activity against Mycobacterial tuberculosis has been demonstrated, but no information regarding its mechanism of action has been documented. Therefore, in this study we carry out the gene expression from total RNA obtained from M. tuberculosis H37Rv treated with MDGA using microarray technology, which was validated by quantitative real time polymerase chain reaction. Results showed that the alpha subunit of coenzyme A transferase of M. tuberculosis H37Rv is present in both geraniol and 1-and 2-methylnaphthalene degradation pathways, which are targeted by MDGA. This assumption was supported by molecular docking which showed stable interaction between MDGA with the active site of the enzyme. We propose that inhibition of coenzyme A transferase of M. tuberculosis H37Rv results in the accumulation of geraniol and 1-and 2-methylnaphtalene inside bacteria, causing membrane destabilization and death of the pathogen. The natural product MDGA is thus an attractive template to develop new anti-tuberculosis drugs, because its target is different from those of known anti-tubercular agents.

4,4'-[(2R*,3R*,4R*,5R*)-3,4-Dimethyl-tetra-hydro-furan-2,5-di-yl]diphenol

The title mol-ecule, C(18)H(20)O(3), is a furan-oid lignan extracted from the leaves of Larrea tridentata. The relative absolute configuration for the four chiral centers was established, showing that this compound is 4-epi-larreatricin, which has been previously reported in the literature. The mol-ecule displays noncrystallographic C(2) symmetry, with the methyl and phenol substituents alternating above and below the mean plane of the furan ring. The conformation of this ring is described by the pseudorotation phase angle P = 171.3° and the maximum out-of-plane pucker ν(m) = 37.7°. These parameters indicate that the furan ring adopts the same conformation as the ribose residues in B-DNA. The packing is dominated by inter-molecular O-H⋯O hydrogen bonds. The phenol hy-droxy groups form chains in the [110] direction and these chains inter-act via O-H⋯O(furan) contacts.

Chemical composition of hexane extract of Citrus aurantifolia and anti-Mycobacterium tuberculosis activity of some of its constituents

The main aim of this study was to isolate and characterize the active compounds from the hexane extract of the fruit peels of Citrus aurantiifolia, which showed activity against one sensitive and three monoresistant (isoniazid, streptomycin or ethambutol) strains of Mycobacterium tuberculosis H37Rv. The active extract was fractionated by column chromatography, yielding the following major compounds: 5-geranyloxypsoralen (1); 5-geranyloxy-7-methoxycoumarin (2); 5,7-dimethoxycoumarin (3); 5-methoxypsoralen (4); and 5,8-dimethoxypsoralen (5). The structures of these compounds were elucidated by 1D and 2D NMR spectroscopy. In addition, GC-MS analysis of the hexane extract allowed the identification of 44 volatile compounds, being 5,7-dimethoxycoumarin (15.79%), 3-methyl-1,2-cyclopentanedione (8.27%), 1-methoxy-ciclohexene (8.0%), corylone (6.93%), palmitic acid (6.89%), 5,8-dimethoxypsoralen (6.08%), a-terpineol (5.97%), and umbelliferone (4.36%), the major constituents. Four isolated coumarins and 16 commercial compounds identified by GC-MS were tested against M. tuberculosis H37Rv and three multidrug-resistant M. tuberculosis strains using the Microplate Alamar Blue Assay. The constituents that showed activity against all strains were 5 (MICs = 25-50 mg/mL), 1 (MICs = 50-100 mg/mL), palmitic acid (MICs = 25-50 mg/mL), linoleic acid (MICs = 50-100 mg/mL), oleic acid (MICs = 100 mg/mL), 4-hexen-3-one (MICs = 50-100 mg/mL), and citral (MICs = 50-100 mg/mL). Compound 5 and palmitic acid were the most active ones. The antimycobacterial activity of the hexane extract of C. aurantifolia could be attributed to these compounds.

2,2'-Dimethoxy-4,4'-[rel-(2R,3S)-2,3-di-methylbutane-1,4-diyl]diphenol

The title mol-ecule, C(20)H(26)O(4), commonly known as meso-dihydro-guaiaretic acid, is a naturally occurring lignan extracted from Larrea tridentata and other plants. The mol-ecule has a noncrystallographic inversion center situated at the midpoint of the central C-C bond, generating the meso stereoisomer. The central C-C-C-C alkyl chain displays an all-trans conformation, allowing an almost parallel arrangement of the benzene rings, which make a dihedral angle of 5.0 (3)°. Both hydr-oxy groups form weak O-H⋯O-H chains of hydrogen bonds along [100]. The resulting supra-molecular structure is an undulating plane parallel to (010).