This study identified the antifungal metabolites produced by Bacillus altitudinis Q7 against Alternaria alternata and investigated the antifungal activity and antifungal action. Lipopeptide, the important secondary metabolites were identified by Fourier transform infrared (FTIR) and liquid chromatography‐mass spectrometry as lichenysin. The antifungal activity of lipopeptide on A. alternata was determined by microdilution technique, and its minimum inhibitory concentration was 1.2 mg/ml. Stability test showed that lipopeptide had excellent temperature and pH resistance. To investigate whether lichenysin acted on the cell membrane and changed its permeability, the ultra‐violet absorption of protein and nucleic acid were measured using a colorimetric method. The antifungal metabolites produced by B. altitudinis Q7 was lichenysin, which showed stable antifungal activity in the extreme environments. Lichenysin could inhibit A. alternata by altering the permeability of cell membrane, leading to the outflow of proteins and nucleic acids from the cytoplasm. This research suggests the lipopeptide from B. altitudinis Q7 is a potential biological control agent against A. alternata.

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The current study was performed to evaluate the beneficial effect in the power output of microbial fuel cells (MFCs) through supplementation of dried red pepper (Capsicum annuum) powder into the anodic chamber. Mediator-less H-type MFCs were set up where the anode chamber contained rumen microorganisms as inocula on cellulose (Avicel) and the cathode chamber of phosphate buffered saline (pH 7.4), both separated by cation exchange membrane. Electrical power generation in MFC was monitored daily over a 10-day period and the accumulated amounts and components of gaseous byproducts were measured at the end of 10 d operation of MFC. For both groups of MFCs with red pepper and the control, the head space gases collected were methane and CO 2 , and its volume and composition were similar between treatments. Methane and CO 2 produced for 10 d operation were 210.7 and 106.5 mL, respectively, in MFC. The addition of red pepper powder caused an average power density to increase from 24.0 mW/m 2 to 39.6 mW/m 2 (P < 0.0001). The greatest power density was 25.9 and 35.6 mW/m 2 for control and bellflower, respectively. This study provides the strong evidence that red pepper (Capsicum annuum) supplementation might modify the anaerobic fermentation characteristics of rumen microorganisms in anode chamber and improve the cellulosic bioenergy production in MFC.