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The authors have recently investigated the chemical components and bioactivity of fungus comb from Macrotermes gilvus Hagen mounds. The ethyl acetate, methanol, and water extracts of the fungus comb contained active compounds which are preventing the growth of Aspergillus foeti-dus, one of the most economically important wood-staining fungi in Indonesia. In this present study, the bioactivity of the fungus comb extracts was examined against the white-rot fungus Schizophyllum commune Fr. For the purpose of generating a realistic in-service type of environment, the extracts were evaluated according to modified EN-113 after impregnated into wood samples by the vacuum-pressure method, following in-vitro antimicrobial susceptibility test. The results showed that ethyl acetate extract at concentrations ranging from 2 to 6% and methanol extract at a concentration of 6% presented high bioactivity against S. commune. This result was established through optical microscopy images, which demonstrated the absence of fungal mycelia in the vessels of wood samples treated with EtOAc extract at concentrations of 2%, 4%, and 6%, as well as MeOH extract with a concentration of 6%. The toxic values of the ethyl acetate and methanol extracts were determined to be 6.17% and 7.72%, respectively. Based on UPLC-HRMS analysis, azelaic acid, and erucamide were discovered as the dominant components in ethyl acetate extracts, which are anticipated to be the most active compounds. It appears that ethyl acetate extract, as well as methanol extract, can be considered as novel preservative sources for controlling wood-decaying fungi. [ABSTRACT FROM AUTHOR]

Actinomycetes are an important microbial resource closely related to human production and life. Approximately 70% of the antibiotics currently used are produced by various actinomycetes. Pine wilt disease (PWD) is caused by the pine wood nematode (PWN) (Bursaphelenchus xylophilus), which is a devastating forest pest that can cause the wilting and death of pine trees. The purpose of this work was to screen out, identify, and ferment active actinomycetes with high lethality to pine wood nematodes and study the active compounds in their secondary metabolites. A group of 227 original strains/isolates of actinomycetes was screened, and Streptomyces sp. TCS19-048 was selected for further analyses. The taxonomic characteristics and molecular analysis results indicated that the strain was a member of the genus Streptomyces and exhibited the highest similarity (99.77%) with the 16S rRNA gene sequences of Streptomyces lactacystinicus OM-6519. Furthermore, the active extract was isolated and had an inhibitory effect on the movement behaviour of B. xylophilus and was able to significantly increase the body fluid leakage of B. xylophilus. This study focused on isolating secondary metabolites from various soil actinomycetes to control PWD and identified an extract with nematicidal activity from a selected strain. The nematicidal effect of extract S-3-1 was confirmed, and the strain Streptomyces sp. TCS19-048 showed good inhibitory activity against B. xylophilus, which was reported for the first time at home and abroad.

Background: Schistosomiasis, a neglected tropical disease, imposes substantial health and economic burdens on impoverished groups living in predominantly rural areas. Praziquantel (PZQ) is the only drug available for treatment, and it is not completely efficacious. Artemisia annua and Artemisia afra infusions were proposed to possess antischistosomal activities in a recently retracted publication of a clinical trial, leading to our investigation in vitro. Objective: The objective was to identify the main components of the infusions and evaluate the in vitro antischistosomal activities of traditionally prepared infusions as well as hexane and dichloromethane (DCM) extracts of the infusions of A. afra and A. annua. Methods: Infusions of A. afra and A. annua were submitted to liquid-liquid partitioning with n-hexane and DCM to provide samples for in vitro bioassays using newly transformed schistosomulas (NTS) and adult Schistosoma mansoni worms obtained from infected mice. The viability of the NTS and adult S. mansoni was visually scored via microscopic readout. Results: Nine phytochemicals comprising coumarins and organic acids were identified. A. afra and A. annua infusions and extracts possess potent in vitro antischistosomal activities against NTS, at 100 μg/ml. However, the A. afra infusions exhibited better activities against NTS than the A. annua infusion. The A. afra hexane- and DCM extracts presented IC50 values that are similar to PZQ (1.5 μg/ml) and approximately five times lower than the comparison drug artesunate (11.6 μg/ml) against NTS. Low IC50 values for both these extracts were also obtained in phenotypic assays with adult S. mansoni. Conclusion: A. afra shows greater antischistosomal potential than A. annua. Thus, further studies are necessary to identify the active molecule(s) responsible for the notable antischistosomal activity of A. afra.

Cigarette smoke (CS) is a common environmental irritant and a risk factor for asthma, as it induces as well as aggravates asthmatic attacks. The injured airway epithelial tight junctions (TJs) aggravate asthma. CS can aggravate asthma by activating the transient receptor potential ankyrin A1 (TRPA1) channel and enhancing TJs destruction. Houpo Mahuang decoction (HPMHD) is a classic traditional Chinese prescription for the treatment of asthma. However, its underlying action mechanism is unclear. The present study aimed to evaluate the effect of HPMHD on the asthma phenotype and the regulation of TRPA1 and TJs in a CS-induced mouse model of aggravated asthma. Under optimized chromatographic and mass spectrometry conditions, the ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) technique was used to detect and analyze the major chemical components of HPMHD. C57BL/6 female mice were randomly divided into seven groups, viz, normal saline (NS) group, ovalbumin (OVA) + CS group, dexamethasone group, HPMHD high-dose group and low-dose groups, n-butanol extract group, and ethyl acetate extract group, with 10 mice in each group. OVA sensitization and challenge, and CS exposure were used to establish the aggravated asthma model. As the main indices to evaluate the protective effect of HPMHD, the eosinophils count in peripheral blood, percentages of inflammatory cells classified and the levels of interleukin (IL)-4, IL-5, IL-13 in the bronchoalveolar lavage fluid (BALF), airway responsiveness enhanced pause (Penh), and changes in lung histopathology were determined and compared among the groups. The mRNA and protein expression of TRPA1 and TJs in lung tissue was also examined. Using UPLC-QTOF-MS, the chemical components of HPMHD, including ephedrine, pseudoephedrine, laetrile, and amygdalin amide, were identified by 51 signal peaks. Compared with those in the NS group, the eosinophil number in the peripheral blood and the eosinophils and neutrophils percentages in BALF of the OVA + CS group were remarkably increased. Following the inhalation of 50 μl of acetylcholine chloride (ACH) at doses of 25 and 50 mg/mL, the Penh increased significantly (p < 0.01). Moreover, in the OVA + CS group, hematoxylin and eosin (H&E) staining of lung tissue showed a significant number of infiltrated inflammatory cells, increased mucus secretion in the lumen, damaged bronchial mucosa, increased thickness of tracheal wall, and increased score of lung damage (p < 0.01). The IL-4/5/13 levels were also remarkably increased (p < 0.01). The protein as well as gene expression of both ZO-1 and occludin decreased markedly in the lung tissue, while the expression of TRPA1 and claudin-2 was increased (p < 0.05, p < 0.01). Next, the OVA + CS group and the treatment groups were compared. The inflammatory cells, Penh value, and levels of IL-4/5/13 were significantly reduced, and less lung injury was observed in the treatment groups. The gene and protein levels of TRPA1 and TJs were corrected (p < 0.05, p < 0.01); the effects on the HPMHD high-dose and ethyl acetate extract groups were particularly remarkable. HPMHD reduced airway hyperresponsiveness, inflammatory cell recruitment and Th2 cytokine secretion in CS-induced aggravated asthma mice, in a manner potentially dependent on regulation of the expression of TRPA1 and TJ proteins. Both the n-butanol and ethyl acetate extracts contained the active ingredients, especially the ethyl acetate extract. [Display omitted] • HPMHD could relieve aggravated asthma phenotype induced by cigarette smoke. • HPMHD could protect the expressions of tight junctions in asthmatic mice. • The mechanism might be related to the regulation of TRPA1 expression. • The n-butanol and ethyl acetate extract of HPMHD played effective roles. [ABSTRACT FROM AUTHOR]

Abstract: Although in vivo models give a more accurate reflection of the activity of substances used in traditional medicine, their use in many countries is severely restricted due to economic and ethical concerns, and this has resulted in the widespread use of in vitro tests in ethnopharmacological studies. Such tests are very useful where the identity of compounds responsible for the biological activity of an extract is being investigated and where limited supplies of material are available, but it is important to consider a variety of factors before making over-predictive claims of that activity in one particular system explains the traditional use. The use of only one bioassay gives a very incomplete picture of the effect of the extract on the whole system involved. A symptom may be due to a number of disease states and, consequently, a variety of mechanisms may serve as targets for bioassays. In a similar way, it is very unusual for there to be only one target for a particular disease so a variety of test systems must be employed. Examples are given of batteries of test systems used to test plants and other materials with a reputation of being useful in wound-healing, diabetes, cancer and to treat cognitive decline associated with old age. In addition, consideration must be given to factors such as absorption into the body and metabolism of any substances present, either to decrease or increase the effect of the ‘actives’. [Copyright &y& Elsevier]

Recently, the architectural and physical properties of the fungus comb from subterranean termite Macrotermes gilvus Hagen (Isoptera: Termitidae) mounds had been studied and it is important to determine its chemical profile as well as to evaluate its anti-staining-fungi activity. The results showed that fungus comb of M. gilvus has a high crude ash (30.57%), fiber (25.46%), starch (7.76%), protein (5.80%, 5.53% amino acid), acid-insoluble ash (3.45%), and fat (0.73%). It also contained phenol hydroquinone, steroids, terpenoids, and saponin compounds. Seventeen amino acids were identified via high-performance liquid chromatography analysis, of which arginine, leucine, glutamate, and aspartic acid were the majority. According to gas chromatography-mass spectrometry analysis, the n-hexane extract consists of several types of fatty acid derivatives. Meanwhile, the ethyl acetate (EtOAc) extracts were primarily phenol groups with 1,2,3-propanetriol (glycerol) at the highest relative concentration. Four fungus-comb extracts (n-hexane, EtOAc, MeOH, and water) inhibited the Aspergillus foetidus fungus, with inhibition rates ranging from 24.17% to 100% and EtOAc extract as the most active extract. It appears that EtOAc extracts from the M. gilvus fungus comb can be considered an active ingredient source of novel organic fungicide in preventing wood-staining fungi attacks on susceptible wood. [ABSTRACT FROM AUTHOR]

Phytophthora infestans is the pathogen causing potato late blight, one of the most serious diseases of potato. Myxobacteria have become a valuable biological control resource due to their preponderant abilities to produce various secondary metabolites with novel structure and remarkable biological activity. In this study, Myxococcus xanthus strain B25-I-1, which exhibited strong antagonistic activity against P. infestans , was isolated from soil sample and identified by 16S rRNA sequence analysis. The strain exhibited antagonistic activity against several species of fungus and bacteria. Analysis of the biocontrol mechanism showed that the active extract produced by strain B25-I-1 had strong inhibitory effects on mycelium and the asexual and sexual reproductive structures of P. infestans. Furthermore, these active extract decreased the content of soluble proteins and activity of the protective enzymes (PPO, POD, PAL, and SOD), increased the oxidative damage and the permeability of the cell membrane in P. infestans. All of these mechanisms might be the biocontrol mechanism of B25-I-1 against P. infestans. The active extract of strain B25-I-1 was separated by TLC and HPLC, and the components with antibiotic activity were detected by HPLC-MS. It was found that the antagonistic components of B25-I-1 contained methyl (2 R)-2-azido-3-hydroxyl-2-methylpropanoate and N-(3-Amino-2-hydroxypropyl)- N -methylsulfuric diamide. The active extract significantly inhibited the infection on detached potato leaves by P. infestans , and these substances did not cause damage to the potato leaves. In conclusion, M. xanthus B25-I-1 produced active extract against P. infestans and might potentially be a candidate to develop into biological pesticides for the control of potato late blight. This study adds to the literature on the isolation and identification of active extracts from myxobacteria, and B25-I-1 in particular, for cures or treatments to potato late blight. [Display omitted] • Myxococcus xanthus B25-I-1, isolated from soil, showed a strong antagonistic against Phytophthora infestans. • Active extract of strain B25-I-1 had strong inhibitory effect on the somatic and reproductive structures of P. infestans. • Active extract reduced the content of soluble proteins and the activity of the protective enzymes in P. infestans. • Active extract increased the oxidative damage and permeability of cell membrane. • Methyl (2 R)-2-azido-3-hydroxyl-2-methylpropanoate and N-(3-Amino-2-hydroxypropyl)- N -methylsulfuric diamide were antagonitistic components. [ABSTRACT FROM AUTHOR]