Frequentin, an antibiotic originally isolated from P. frequentans, is active against bacteria (MICs = 200 and 300 µg ml for B. subtilis and S. aureus, respectively) and fungi.
Ajoene is a disulfide that has been found inA. sativumand has diverse biological activities, including antibacterial, anticancer, antiplatelet, and antioxidant properties.1,2,3,4It is active against Gram-positive (MICs = 5-160 µg ml) and Gram-negative bacteria (MICs = 136-200 µg ml), as well as yeasts (MICs = 10-20 µg ml).1Ajoene is cytotoxic to mouse melanoma cells (IC50= 18 µM), as well as human colon, lung, mammary, and pancreatic cancer cells (IC50s = 7-41 µM).2It reduces tumor growth in a B16 BL6 mouse model of melanoma when administered at a dose of 25 mg kg every other day and decreases the number of lung metastases when administered prior to tumor cell inoculation at doses ranging from 1-25 mg kg. It inhibits ADP- or collagen-induced platelet aggregation in isolated baboon platelets when used at concentrations ranging from 75 to 150 µg ml and in platelet-rich plasma isolated from baboons when administered at a dose of 25 mg kg.3Ajoene (25 mg kg) prevents thrombus formation on damaged arterial walls in heparinized pigs in anin situmodel of thrombogenesis.5It also reduces high-fat diet-induced hepatic steatosis, histopathological markers of liver damage, thiobarbituric acid reactive substances (TBARS) formation, and protein oxidation in a mouse model of non-alcoholic fatty liver disease (NAFLD).4 1.Naganawa, R., Iwata, N., Ishikawa, K., et al.Inhibition of microbial growth by ajoene, a sulfur-containing compound derived from garlicAppl. Environ. Microbiol.62(11)4238-4242(1996) 2.Taylor, P., Noriega, R., Farah, C., et al.Ajoene inhibits both primary tumor growth and metastasis of B16 BL6 melanoma cells in C57BL 6 miceCancer Lett.239(2)298-304(2006) 3.Teranishi, K., Apitz-Castro, R., Robson, S.C., et al.Inhibition of baboon platelet aggregation in vitro and in vivo by the garlic derivative, ajoeneXenotransplantation10(4)374-379(2003) 4.Han, C.Y., Ki, S.H., Kim, Y.W., et al.Ajoene, a stable garlic by-product, inhibits high fat diet-induced hepatic steatosis and oxidative injury through LKB1-dependent AMPK activationAntioxid. Redox Signal.14(2)187-202(2011) 5.Apitz-Castro, R., Badimon, J.J., and Badimon, L.A garlic derivative, ajoene, inhibits platelet deposition on severely damaged vessel wall in an in vivo porcine experimental modelThromb. Res.75(3)243-249(1994)
4’-hydroxy Trazodone is a metabolite of the antidepressant and sedative trazodone.1It is an inhibitor of organic anion transporter 3 (OAT3; Ki= 16.9 μM) and is selective for OAT3 over OAT1 (Ki= >200 μM).2 1.Yamato, C., Takahashi, T., Fujita, T., et al.Studies on metabolism of trazodone, II. Metabolic fate after intravenous administration and effects on liver microsomal drug-metabolizing enzymes in ratsXenobiotica4(12)765-777(1974) 2.Zou, L., Matsson, P., Stecula, A., et al.Drug metabolites potently inhibit renal organic anion transporters, OAT1 and OAT3J. Pharm. Sci.110(1)347-353(2021)
Paraherquamide A is a mycotoxin anthelmintic originally isolated from P. paraherquei. It binds to acetylcholine receptors (IC50 = 0.5 nM for head homogenates of M. domestica) and acts as an antagonist. Paraherquamide A is toxic to C. elegans (LD50 = 2.5 μg/ml) and effective against T. colubriformis infection in gerbils when used at doses ranging from 0.39 to 200 mg/kg. It is toxic to mice (LD50 = 14.9 mg/kg).
Flumequine-13C3is intended for use as an internal standard for the quantification of flumequine by GC- or LC-MS. Flumequine is a fluoroquinolone antibiotic.1It is active againstS. aureus, S. pyogenes, B. subtilis, E. coli, P. aeruginosa, S. faecalis, andK. pneumoniae(MICs = 1-100 μg ml). Flumequine is also active against field isolates of B. hyodysenteriae (MICs = 6.25-200 μg ml).2It inhibits DNA gyrase, disrupting supercoiling of bacterial DNA to block transcription and replication.3In vivo, flumequine (50 mg kg) increases survival in rat models ofP. vulgaris-induced urinary tract infection andP. mirabilis-induced prostatitis.1Formulations containing flumequine have been used in the treatment of urinary tract infections in veterinary medicine. 1.Rohlfing, S.R., Gerster, J.R., and Kvam, D.C.Bioevaluation of the antibacterial flumequine for urinary tract useAntimicrob. Agents Chemother.10(1)20-24(1976) 2.Aller-Morán, L.M., Martínez-Lobo, F.J., Rubio, P., et al.Evaluation of the in vitro activity of flumequine against field isolates of Brachyspira hyodysenteriaeRes. Vet. Sci.10351-53(2015) 3.Smith, J.T.The mode of action of 4-quinolones and possible mechanisms of resistanceJ. Antimicrob. Chemother.18 (Suppl. D)21-29(1986)
Terpendole I is a fungal metabolite that has been found in A. yamanashiensis.1 It is a weak inhibitor of acyl-coenzyme A:cholesterol acyltransferase (ACAT; IC50 = 145 μM) and is active against the bacteria B. cereus and B. subtilis (MICs = 100 μg/ml for both) but not S. aureus, P. aeruginosa, or K. pneumoniae (MICs = >200 μg/ml for all) or the fungus C. albicans (MIC = 200 μg/ml).1,2 It is cytotoxic to HeLa cells with an IC50 value of 52.6 μM.3 |1. Tomoda, H., Tabata, N., Yang, D.-J., et al. Terpendoles, novel ACAT inhibitors produced by Albophoma yamanashiensis. III. Production, isolation and structure elucidation of new components. J. Antibiot. (Tokyo) 48(8), 793-804 (1995).|2. Zhao, J.-C., Wang, Y.-L., Zhang, T.-Y., et al. Indole diterpenoids from the endophytic fungus Drechmeria sp. as natural antimicrobial agents. Phytochemistry 148, 21-28 (2018).|3. Nagumo, Y., Motoyama, T., Hayashi, T., et al. Structure-activity relationships of terpendole E and its natural derivatives. ChemistrySelect 2(4), 1533-1536 (2017).
Enopeptin A, originally isolated from a culture broth of Streptomyces sp. RK-1051, is a depsipeptide antibiotic that contains two unusual amino acids (N-methylalanine and 4-methylproline) and features a pentaenone side chain. It is effective against Gram-positive bacteria, including methicillin-resistant S. aureus (MIC = 25 μg ml), and Gram-negative bacteria, including mutant forms of E. coli and P. aeruginosa (MICs = 200 μg ml); however, it is not inhibitory to fungi.
Givinostat (ITF-2357) is a HDAC inhibitor with an IC50 of 198 and 157 nM for HDAC1 and HDAC3, respectively. Givinostat (ITF2357) suppresses total LPS-induced IL-1β production robustly compared with the reduction by ITF3056. At 25, 50, and 100 nM, Givinostat reduced IL-1β secretion more than 70%. Givinostat (ITF-2357) suppresses the production of IL-6 in PBMCs stimulated with TLR agonists as well as the combination of IL-12 plus IL-18. IL-6 secretion decreases to 50% at 50 nM Givinostat, but at 100 and 200 nM, there is no reduction[1]. As shown by the CCK-8 assay, Givinostat (ITF-2357) inhibits JS-1 cell proliferation in a concentration-dependent manner. Treatment with Givinostat ≥500 nM is associated with significant inhibition of JS-1 cell proliferation (P<0.01). Also, the cell inhibition rate significantly differs between the group cotreated with Givinostat ≥250 nM plus LPS and the group without LPS treatment (same Givinostat concentration) (P<0.05)[2]. Givinostat (ITF2357) at 10 mg kg is used as a positive control and, as expected, reduced serum TNFα by 60%. Strikingly, pretreatment of ITF3056 starting at 0.1 mg kg significantly reduces the circulating TNFα by nearly 90%. To achieve a significant increase in serum IL-1β production, a higher dose of LPS is injected (10 mg kg), and blood is collected after 4 h. Similarly, when pretreated with lower doses of Givinostat (ITF-2357) (1 or 5 mg kg), there is a 22% reduction for 1 mg kg and 40% for 5 mg kg[1]. [1]. Li S, et al. Specific inhibition of histone deacetylase 8 reduces gene expression and production of proinflammatory cytokines in vitro and in vivo. J Biol Chem. 2015 Jan 23;290(4):2368-78. [2]. Wang YG, et al. Givinostat inhibition of hepatic stellate cell proliferation and protein acetylation. World J Gastroenterol. 2015 Jul 21;21(27):8326-39. [3]. Leoni F, et al. The histone deacetylase inhibitor ITF2357 reduces production of pro-inflammatory cytokines in vitro and systemic inflammation in vivo. Mol Med. 2005 Jan-Dec;11(1-12):1-15.
AN3661, a potent antimalarial lead compound, targets a Plasmodium falciparum cleavage and polyadenylation specificity factor homologue subunit 3 (PfCPSF3). AN3661 inhibits Plasmodium falciparum laboratory-adapted strains, Ugandan field isolates, and murine P. berghei and P. falciparum infections[1]. AN3661 is active at nanomolar (IC50=20-56 nM) concentrations against P. falciparum laboratory strains known to be sensitive (3D7) or resistant (W2, Dd2, K1, HB3, FCR3 and TM90C2B), and AN3661 is similarly active in ex vivo studies of fresh Ugandan field isolates (mean ex vivo IC50=64 nM). AN3661 shows minimal cytotoxicity against mammalian cell lines, with the CC50 60.5 μM against Jurkat cells, and all other CC50 values greater than the highest concentrations tested (25 μM or above)[1].AN3661 inhibits the stability of P. falciparum transcripts[1]. AN3661 (50-200 mg.kg; p.o.; daily for 4 days) inhibits murine P. berghei infections with ED90 (4 days) 0.34 mg kg[1].AN3661 is administered orally for 4 days, beginning on the third day of infection, the ED90 4 days after initiation of treatment is 0.57 mg kg[1]. Animal Model: P. berghei-infected mice (malaria model)[1] [1]. Sonoiki E, et al. A potent antimalarial benzoxaborole targets a Plasmodium falciparum cleavage and polyadenylation specificity factor homologue. Nat Commun. 2017;8:14574. Published 2017 Mar 6.
N-3-oxo-pentanoyl-L-Homoserine lactone is a chain-shortened derivative of the bacterial quorum sensing signaling molecule N-3-oxo-octanoyl-L-homoserine lactone .1It inhibits binding of the autoinducer N-3-oxo-hexanoyl homoserine lactone toE. colicontaining the transcription factor LuxR when used at a concentration of 230 nM.2It acts as an autoinducer to activate theV. fischeriluminescence system inE. coliwhen used at concentrations ranging from 20 to 200 nM. 1.Chhabra, S.R., Stead, P., Bainton, N.J., et al.Autoregulation of carbapenem biosynthesis in Erwinia carotovora by analogues of N-(3-oxohexanoyl)-L-homoserine lactoneJ. Antibiot. (Tokyo)46(3)441-454(1993) 2.Schaefer, A.L., Hanzelka, B.L., Eberhard, A., et al.Quorum sensing in Vibrio fischeri: Probing autoinducer-LuxR interactions with autoinducer analogsJ. Bacteriol.178(10)2897-2901(1996)
CP21 is an iron chelator that binds to iron in a 3:1 (ligand:iron) ratio. It is active against P. falciparum when used at concentrations of 10 and 100 µM. CP21 inhibits production of prostaglandin I2 induced by epinephrine, arachidonic acid, or A23187 in isolated rat aortic rings with IC50 values of 1.3, 1.3, and 1.4 mM, respectively. It inhibits glutamate-induced oxytosis, as well as decreases iodoacetic acid-induced cytotoxicity in an in vitro model of ischemia, in HT22 mouse hippocampal cells (EC50s = 13 and 9.5 µM, respectively). CP21 (200 mg kg) increases the excretion of iron, but not copper, zinc, calcium, or magnesium, in rabbits.
Dihydroaeruginoic acid, an antibiotic sourced originally from P. fluorescens, exhibits antimicrobial efficacy in disc assays against diverse pathogens, including R. solani, P. ultimum, B. cinerea, S. rolfsii, C. gloeosporioides, F. oxysporum, and S. tritici fungi, along with B. subtilis, E. herbicola, and S. albus bacteria, at a concentration of 200 μg disc.