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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 .

Endophytic fungal isolates Hypocrea lixii F3ST1 and Beauveria bassiana G1LU3 were evaluated for their potential to endophytically colonize and induce active compounds in Phaseolus vulgaris , as a defense mechanism against pea leafminer ( Liriomyza huidobrensis ) and fall armyworm ( Spodoptera frugiperda ). Endophytic colonization was achieved through seed inoculation with the volatile emissions from P. vulgaris plants being analyzed using GC-MS. The crude extracts of P. vulgaris obtained using methanol and dichloromethane were assayed against leafminer and fall armyworm larvae using leaf dipping and topical application, respectively. The two isolates successfully colonized the entire host plant (roots, stems, and leaves) with significant variation ( p < 0.001) between fungal isolates and the controls. The results showed qualitative differences in the volatile profiles between the control plants, endophytically colonized and insect-damaged plants attributed to fungal inoculation and leafminer damage. The crude methanol extracts significantly reduced the percentage pupation of 2nd instar leafminer larvae ( p < 0.001) and adult-flies emergence ( p < 0.05). The survival of the 1st instar fall armyworm larvae was also significantly reduced ( p < 0.001) compared to the controls. This study demonstrated the high potential of endophytic fungi H. lixii and B. bassiana in inducing mainly specific defense compounds in the common bean P. vulgaris that can be used against pea leafminer and fall armyworm.

Ethnopharmocological Relevance: Members of 'Mycoplasma mycoides cluster' are important ruminant pathogens in Africa. Diseases caused by these Mycoplasma negatively affect the agricultural sector especially in developing countries through losses in livestock productivity, mortality and international trade restrictions. There is therefore urgent need to develop antimicrobials from alternative sources such as medicinal plants to curb these diseases. In Kenya, smallholder farmers belonging to the Maasai, Kuria and Luo rely on traditional Kenyan herbals to treat respiratory symptoms in ruminants. In the current study extracts from some of these plants were tested against the growth of members of Mycoplasma mycoides cluster., Aim: This study aimed at identifying plants that exhibit antimycoplasmal activities using an ethnobotanical approach., Materials and Methods: Kenyan farmers of Maasai, Luo and Kuria ethnic groups were interviewed for plant remedies given to livestock with respiratory syndromes. The plant materials were thereafter collected and crude extracts prepared using a mixture of 50% of methanol (MeOH) in dichloromethane (CH 2 Cl 2 ), neat methanol (MeOH), ethanol (EtOH) and water to yield four crude extracts per plant part. The extracts were tested in vitro against five strains of Mycoplasma mycoides subsp. capri, five strains of Mycoplasma mycoides subsp. mycoides and one strain of Mycoplasma capricolum subsp capricolum using broth micro-dilution assays with an initial concentration of 1mg/ml. Minimum inhibitory concentration (MIC) of the most active extracts were determined by serial dilution., Results: Extracts from five plants namely: Solanum aculeastrum, Albizia coriaria, Ekebergia capensis, Piliostigma thonningii and Euclea divinorum exhibited the highest activities against the Mycoplasma strains tested. Mycoplasma mycoides subsp. mycoides were more susceptible to these extracts than Mycoplasma mycoides subsp. capri and Mycoplasma capricolum susp. capricolum. The activities of the crude extracts varied with the solvent used for extraction. The MICs mean values of the active extracts varied from 0.02 to 0.6mg/ml., Conclusions: The results suggested that these plants could potentially contain antimicrobial compounds that might be useful for the treatment of respiratory diseases in ruminants. Future work should focus on the isolation and identification of the active compounds from the plant extracts that showed interesting activities and evaluation of their antimicrobial and cytotoxic potential., (Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.)

Introduction: Macaranga species are traditionally used for the treatment and management of coughing, fungal infection, and wounds. In this study, the phytochemical screening and antibacterial activities of nine crude extracts from Macaranga conglomerata, Macaranga kilimandscharica and Macaranga capensis were determined against 13 bacterial strains expressing multi-drug resistance (MDR) phenotypes. Methods: Phytochemical screening of the extracts were carried out according to the standard methods, while the iodonitrotetrazolium chloride (INT) colorimetric assay was used to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of the plants extracts. Results: Flavonoids, terpenoids, saponins and coumarins were the major secondary metabolites found in all the plant extracts. The results of antibacterial studies revealed that all the plant extracts displayed good activities with MIC values ranging from 4 - 128 μg/mL against the tested micro-organisms. Most of the extracts exhibited a bactericidal effect against E. coli, E. aerogenes, K. pneumoniae, P. stuartii, P. aeruginosa, and S. aureus with MBC/MIC ratio ≤ 4. In the presence of efflux pump inhibitor (PaβN), the inhibition potency of all the crude extracts against the tested bacterial strains were substantially enhanced. It is worth noting that the activities of MKL, MCL, and MCR towards P. stuartii (NEA16), E. aerogenes (ATCC13048), and K. pneumoniae (KP55), respectively were improved by more than 8-fold in the presence of PAβN. Conclusion: The findings of this study indicated the possibility of using all the tested plant extracts as a source of therapeutic agents in the fight against multi-drug resistant bacteria. [ABSTRACT FROM AUTHOR]

Introduction: Plants from Kenyan flora are traditionally used to manage a number of ailments including; chronic and infectious disease, to bolster the body immunity and for general health protections. The current investigation was designed to validate the quality with respect to the pharmacological significance of 156 fresh plant materials resulting from 27 ethno-medicinal plants, from Ngong forest, Kenya. Materials and Methods: Pharmacological screening was carried out using the field deployable GIBEX Screens- To-Nature (STN) validated assays. The plant extracts were screened for antifungal; general protozoal lethality; round worm lethality and antioxidant potential. Results: Different plant parts exhibited a range of activities; related to their traditional uses; with eleven out of twenty-seven extracts exhibiting highest activities in only one out of four categories of assays studied. All plant parts of only one plant C. axillaris exhibited high activities in all (4/4) the categories of assays evaluated. The other plants that exhibited high activities in three out of four (3/4) categories of assays studied included; A. oppositifolia, B. huillensis and T. trichocarpa. Conclusion: The current investigation provided additional data in relation to the usefulness of the studied ethno-medicinal plants, mostly of the following plants; C. axillaris, A. oppositifolia, B. huillensis and T. trichocarpa in the management of diseases that are infectious and to bolster the immunity. The reported data will contribute towards authenticating the claimed traditional use of these plants. The extracts that exhibited high activities should be investigated further to determine their effective concentrations. [ABSTRACT FROM AUTHOR]

Four new steroidal sapogenins, dracaenogenins C F (1 – 4), a new conjugated chalcone-stilbene, 3′′-methoxycochinchinenene H (5) together with eight known compounds namely, (25 S)-spirosta-1,4-dien-3-one (6), trans -resveratrol (7), 4,4′-dihydroxy-3′-methoxychalcone (8), N - trans -coumaroyltyramine (9), N - trans - p -coumaroyloctopamine (10), N - trans -feruloyloctopamine (11), 7-hydroxy-1-(4-hydroxy-3-methoxyphenyl)- N 2 , N 3 - bis (4-hydroxyphenethyl)-6-methoxy-1,2-dihydronaphthalene-2,3-dicarboxamide (12) and grossamide (13) were isolated from the stems of Dracaena usambarensis Engl. from Kenya. It is important to note that compounds 12 and 13 are being reported from this genus for the first time. Structural elucidation of the isolated compounds was done using spectroscopic (NMR, UV, IR, optical rotation) and spectrometric (HRESIMS) techniques. The absolute and relative configurations of the isolated compounds were determined by employing single crystal X-ray crystallography analysis, NOESY correlations and coupling constants. The anti-inflammatory potencies of the isolated compounds were evaluated by measuring the levels of four cytokines (IL-1β, IL-2, GM-CSF and TNF-α) in the supernatant media of human peripheral blood mononuclear cells (PBMCs) stimulated by lipopolysaccharide (LPS). At the tested concentration of 100 μM, the new conjugated chalcone-stilbene 5 , the dihydrochalcone, 8 and the lignanamide, 13 were substantially more potent than the standard drug, ibuprofen, inhibiting the release of all the cytokines, IL-1β , IL-2, GM-CSF and TNF-α from 0.06–58.04% compared to LPS control. These compounds should therefore be considered for development into anti-inflammatory drug candidates. Compound 7 significantly decreased the release of GM-CSF (6.11% of LPS control) and TNF-α (18.35% of LPS control). The cytokine TNF-α was sensitive to all the tested compounds 1 - 13. Unlabelled Image • Thirteen secondary metabolites isolated from the stem bark of Dracaena usambarensis. • Four new steroidal sapogenins, 1 - 4 and a new conjugated chalcone-stilbene, 5. • The relative configuration of 1 was confirmed with X-ray analysis. • Inhibitory activity of 5 , 8 and 13 , was higher than ibuprofen against all cytokines. [ABSTRACT FROM AUTHOR]

Two new norhopane derivatives namely 3β,6β,22-trihydroxy-7β,11α-di[(4-hydroxybenzoyl)oxy]-21αH-24-norhopa-4(23)-ene (1) and 3β,6β,22-trihydroxy-7β-[(4-hydroxybenzoyl)oxy]-21αH-24-norhopa-4(23)-ene (2) together with two previously reported compounds, including a norhopane, 3β,6β,11α-trihydroxy-7β-[(4-hydroxybenzoyl)oxy]-24-norhopa-4(23),17(21)-diene (3) and a norneohopane, (21αH)-24-norneohopa-4(23), 22(29)-diene-3β,6β,7β-triol 7-caffeate (4) were isolated from the root bark of Fagaropsis angolensis. Elucidation of their structures was achieved by spectroscopic (NMR, IR and UV) and spectrometric (HRESIMS) data and by comparison of these data with those of related compounds in the literature. Compounds 1–4 were evaluated for their anti-inflammatory activity by measuring the levels of cytokines, IL-1β, IL-2, GM-CSF and TNF-α in lipopolysaccharide (LPS) stimulated peripheral blood mononuclear cells (PBMC). All tested compounds decreased secretion of IL-1β and TNF-α. Compounds 2 and 4 caused significant decrease of the production of IL-2, GM-CSF and TNF-α compared to the reference drug, ibuprofen. These findings showed that the root barks of F. angolensis are rich source of norhopane derivatives and further provide a scientific rationale of using this plant in Kenyan folk medicine to relieve pain. Unlabelled Image [ABSTRACT FROM AUTHOR]