Antioxidant compounds produced by endolichenic fungus Penicillium sp.-strain 1322P isolated from Pyxine subcinerea.

Endolichenic fungi are expecting for new bioresources of pharmacological compounds. However, the number of investigations targeting antioxidant compounds produced by endolichenic fungi remains limited. To discover new antioxidant compounds, we analyzed the antioxidant activity of the methanol extracts derived from isolated lichen mycobionts or endolichenic fungi induced from Pyxine subcinerea. We performed this analysis using the oxygen radical absorbance capacity (ORAC) method. As a result, we isolated from an endolichenic fungus identified as Penicillium sp.-stain 1322P in Pyxine subcinerea. This fungus produced a red pigment, and its chemical structure was determined to be sclerotioramine based on the analytical data obtained from NMR, LC-MS/MS, and HPLC-PDA. Sclerotioramine exhibited high antioxidant activity, and the ORAC values (mean ± SD) of sclerotioramine and sclerotiorin were 11.4 ± 0.36 and 4.86 ± 0.70 mmol TE per gram of the respective pure compound. Thus, the antioxidant activity of sclerotioramine was greater than twice that of sclerotiorin. This work represents the first report that the antioxidant activity of sclerotioramine is higher than that of the sclerotiorin.

A needle-type micro-sampling device for collecting nanoliter sap sample from plants.

In plant research, measuring the physiological parameters of plants is vital for understanding the behavior and response of plants to changes in the external environment. Plant sap analysis provides an approach for elucidating the physiological condition of plants. However, to facilitate accurate sap analysis, a sampling device capable of collecting sap samples from plants is required. In this paper, a minimally invasive, needle-type micro-sampling device capable of collecting nanoliter (~ 91 nL) quantities of sap from plants is described. The developed micro-sampling system showed great reproducibility (3%) in experiments designed to assess sampling performance. As a proof of concept, sap samples were collected continuously from target plants with the micro-sampling system, and the dynamic changes in potassium ions, plant hormones and sugar levels inside plants were analyzed. The results demonstrated the feasibility of the micro-sampling device and its potential for developing a measurement system for plant research in the future.

Norlichexanthone produced by cultured endolichenic fungus induced from Pertusaria laeviganda and its antioxidant activity.

Endolichenic fungi, nonobligate microfungi that live in lichen, are promising as new bioresources of pharmacological compounds. We found that norlichexanthone isolated from the endolichenic fungus in Pertusaria laeviganda exhibited high antioxidant activity. Norlichexanthone produced by endolichenic fungus had the antioxidant activity with same level of ascorbic acid. This is the first report of high antioxidant activity of norlichexanthone. Abbreviations: AAPH: 2,2'-azobis (2-methylpropionamidine) dihydrochloride; DPPH: 2,2-diphenyl-1-picrylhydrazyl; FL: fluorescein sodium salt; HPLC-PDA: high-performance liquid chromatography with photodiode array; LC-ESI-MS: liquid chromatography with electrospray ionization mass spectrometry; ORAC: oxygen radical absorbance capacity; PB: phosphate buffer; ROS: reactive oxygen species; TLC: thin-layer chromatography.