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Caffeic acid (CA) is a polyphenol belonging to the phenylpropanoid family, commonly found in plants and vegetables. It was first identified by Hlasiwetz in 1867 as a breakdown product of caffetannic acid. CA is biosynthesized from the amino acids tyrosine or phenylalanine through specific enzyme-catalyzed reactions. Extensive research since its discovery has revealed various health benefits associated with CA, including its antioxidant, anti-inflammatory, and anticancer properties. These effects are attributed to its ability to modulate several pathways, such as inhibiting NFkB, STAT3, and ERK1/2, thereby reducing inflammatory responses, and activating the Nrf2/ARE pathway to enhance antioxidant cell defenses. The consumption of CA has been linked to a reduced risk of certain cancers, mitigation of chemotherapy and radiotherapy-induced toxicity, and reversal of resistance to first-line chemotherapeutic agents. This suggests that CA could serve as a useful adjunct in cancer treatment. Studies have shown CA to be generally safe, with few adverse effects (such as back pain and headaches) reported. This review collates the latest information from Google Scholar, PubMed, the Phenol-Explorer database, and ClinicalTrials.gov, incorporating a total of 154 articles, to underscore the potential of CA in cancer prevention and overcoming chemoresistance. [ABSTRACT FROM AUTHOR]

The root extract of Suregada zanzibariensis Baill. afforded six previously described ent-abietane diterpenoids, namely 7-oxo-ent-abieta-5(6),8(14),13(15)-trien-16,12-olide (1), mangiolide (2), 8,14β:11,12α-diepoxy-13(15)-abietane-16,12-olide (3), 7β,11β,12β-trihydroxy-ent–abieta-8(14),13(15)-diene-16,12-olide (4), 8α,14-dihydro-7-oxo-jolkinolide E (5), jolkinolide A (6), together with 3β-sitosterol (7), scopoletin (8) and vanillin (9). Their structures were deduced through 1D and 2D NMR spectroscopic techniques, and HRESIMS, as well as by comparison of the NMR data with those reported in the literature. The crude extract and compounds 1–9 were evaluated for their antiplasmodial, antifungal and antibacterial activities. Mangiolide (2) showed strong in vitro antiplasmodial activity against chloroquine sensitive (D6) and resistant (W2) strains of Plasmodium falciparum with IC50 values of 0.79 and 0.87 µg/mL, respectively, while 3 (IC50 1.24 and 1.17 µg/mL) was less active than 2. Compound 2 also displayed antimicrobial activity against Cryptococcus neoformans, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VRE) with IC50 values of 1.20, 3.90 and 7.20 µg/mL, respectively. [ABSTRACT FROM AUTHOR]

Species of the genus Garcinia (Clusiaceae) have been used for centuries in different folk medicine for the treatment of several ailments, as well as food supplements. Evidence from previous studies has demonstrated a rich depository of structurally diverse secondary metabolites with a wide array of biological activities. The present chapter summarizes the information on the ethnobotany, phytochemistry, and antibacterial potential of the Garcinia genus against drug-sensitive and multi-drug resistant (MDR) phenotypes. A literature survey of the published information was collected from databases such as Google Scholar, PubMed, SciFinder, Scopus, Web of Science, conference proceedings, books, M.Sc., and Ph.D. dissertations. Phytochemical studies showed that xanthones, benzophenones, and flavonoids as the main secondary metabolites. Pharmacological investigations with crude extracts and isolated compounds from G. kola, G. lucida, G. nobilis as well as other Garcinia species revealed a broad range of antibacterial activity against several drug-sensitive and MDR phenotypes. Among the isolated compounds, a-mangostin, a prenylated xanthone from G. mangostana was found to display the most potent antibacterial effects against both Gram-positive and Gram-negative bacteria while (-)-hydroxycitric acid from some Garcinia fruits is utilized in the pharmaceutical industry as an anti-obesity agent. Thus, this review demonstrated that there are convincing in vitro studies confirming the traditional use of Garcinia species to treat bacterial infections. Furthermore, the reviewed data herein would be a valuable reference tool for future researchers seeking to explore the application potentials of Garcinia species for the development of antibacterial agents. [ABSTRACT FROM AUTHOR]

To overcome the negative impacts of invasive fall armyworm (FAW), this study assessed the laboratory and field efficacy of aqueous and oil-based formulations of Metarhizium anisopliae ICIPE 41 as an alternative source for FAW management. Three oil formulations, including canola, corn, olive and an aqueous formulation of ICIPE 41, were assessed against the second-instar larvae of FAW in the laboratory. Field experiments were also conducted at Mbita and Migori, Kenya, using the best formulation, with four treatments: (a) A corn oil formulation of ICIPE 41; (b) Mazao Achieve® biopesticide, with the M. anisopliae ICIPE 78 strain as the active ingredient; (c) spinetoram-based synthetic pesticide; (d) a control (water + corn oil), where the FAW incidence, infestation, larval mortality and the effects on parasitoids and yield were evaluated. The laboratory results showed no significant differences in the efficacies among the oil-based formulations, with mortality rates of >70% and an LT50 of ~2 days compared to 15.15% in the controls with an LT50 of 8.11 days. Under the field conditions, no significant differences in the FAW infestation were observed between ICIPE 41 and Mazao Achieve®, compared to the control treatments in both agro-ecological zones. From the field-collected samples, both fugal-based biopesticides exhibited high mortality and mycosis rates, with no negative impacts on Cotesia icipe compared to the spinetoram pesticide. There were significant differences in the total grain yields among the treatments in Mbita and Migori. ICIPE41 could, therefore, be formulated in corn oil to promote sustainable FAW management in maize cropping systems. [ABSTRACT FROM AUTHOR]

Purification of the aerial parts of Vernonia auriculifera Hiern afforded steroids (1–2), flavonoids (3–5), and polyalcohol (6). Their structures were determined using spectral evidences as well as by comparison with reported data. Iodonitrotetrazolium chloride (INT) colorimetric assay was used to assess the antibacterial activity of the extract and isolates against 13 pathogenic strains. The crude extract showed strong antibacterial activity (MIC < 100 µg/mL) against the tested bacterial strains. When combined with an efflux pump inhibitor phenylalanine beta naphthylamide (PAβN), the inhibition potency of the extract was substantially enhanced with the lowest MIC value at 4 µg/mL. Compounds 5 and 6 showed moderate activity (MIC < 100 µg/mL) against 12/13 (92.3%), and 8/13 (61.5%) bacterial strains, respectively. A minimal bactericidal concentration (MBC)/minimal inhibitory concentration (MIC) ratio ≤ 4 indicated their bactericidal effect against Escherichia coli, Enterbacter aerogenes, Klebsiella pneumoniae, Providencia stuartii, Pseudomonas aeruginosa, and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Chemical investigation of the root of Zanthoxylum paracanthum afforded 1 new alkamide derivative, (2E,4E)-6-oxo-N-isobutyldeca-2,4-dienamide (1) together with 10 known congeners including one phenolic amide (2), four benzophenanthridines (3 − 6), three indolonaphthyridines (7 − 9) and two lignans (10 and 11). Their structures were elucidated by a combination of spectroscopic and spectrometric data. Using resazurin reduction assay, the crude extract (10 µg/mL) and isolates (10 µM) were screened for their cytotoxic activities against the drug-sensitive (CCRF-CEM) leukemia cell line and its multidrug-resistant counterpart (CEM/ADR5000). Compounds 3, 4 and 6 showed cytotoxicity against CCRF-CEM with IC50 values of 2.00 ± 0.33, 2.31 ± 0.20 and 0.11 ± 0.04 µM, respectively. Only compound 6 exhibited strong cytotoxic activity against CEM/ADR5000 with an IC50 value of 2.34 ± 0.34 µM in comparison with the standard drug doxorubicin which showed IC50 values of 0.01 ± 0.14 (CCRF-CEM) and 26.78 ± 3.30 µM (CEM/ADR5000). [ABSTRACT FROM AUTHOR]

The present chapter highlights the antibacterial potential of nine highly active compounds isolated from the African medicinal plants: 8,8-bis-(dihydroconiferyl)-diferulate, buesgenine, candidone, diospyrone, ferruginin A, isobavachalcone, neobavaisoflavone, neocyclomorusin, and plumbagin. Their botanical source as well as their hypothetical biosynthetic pathways have also been discussed. Regarding their inhibitory potential towards the Gram-negative and Gram-positive bacteria, and mycobacteria, the above phytochemicals constitute potential pharmaceuticals that deserve clinical studies to develop antibacterial drugs to combat bacterial infections involving both drug-sensitive and drug-resistant phenotypes. [ABSTRACT FROM AUTHOR]

The root extract of Suregada zanzibariensis Baill. afforded six previously described ent -abietane diterpenoids, namely 7-oxo- ent -abieta-5(6),8(14),13(15)-trien-16,12-olide ( 1 ), mangiolide ( 2 ), 8,14 β :11,12 α -diepoxy-13(15)-abietane-16,12-olide ( 3 ), 7 β ,11 β ,12 β -trihydroxy- ent -abieta-8(14),13(15)-diene-16,12-olide ( 4 ), 8α,14-dihydro-7-oxo-jolkinolide E ( 5 ), jolkinolide A ( 6 ), together with 3 β -sitosterol ( 7 ), scopoletin ( 8 ) and vanillin ( 9 ). Their structures were deduced through 1D and 2D NMR spectroscopic techniques, and HRESIMS, as well as by comparison of the NMR data with those reported in the literature. The crude extract and compounds 1 - 9 were evaluated for their antiplasmodial, antifungal and antibacterial activities. Mangiolide ( 2 ) showed strong in vitro antiplasmodial activity against chloroquine sensitive (D6) and resistant (W2) strains of Plasmodium falciparum with IC 50 values of 0.79 and 0.87 µg/mL, respectively, while 3 (IC 50 1.24 and 1.17 µg/mL) was less active than 2 . Compound 2 also displayed antimicrobial activity against Cryptococcus neoformans , methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VRE) with IC 50 values of 1.20, 3.90 and 7.20 µg/mL, respectively.