A modern concept for Helicascus with a Pleurophomopsis-like asexual state

Helicascus presently comprises two marine species, H. kanaloanus and H. nypae. During investigations of freshwater ascomycetes in Egypt, Malaysia and northern Thailand, we collected two new species of Helicascus from freshwater, which is a new habitat for the genus. Helicascus aegyptiacus sp. nov. is characterised by its smaller asci and ascospores with verruculose walls. Helicascus aquaticus sp. nov. is distinct in having 1-3-septate ascospores and producing a Pleurophomopsis-like anamorph when grown in water agar with sterilized pine needles. During this study we also collected Massarina thalassioidea from freshwater and molecular data confirm this as a species of Helicascus. Thus, we combine this species under Helicascus. All Helicascus species, Massarina thalassioidea and Morosphaeria elaterascus form a strongly supported monophyletic clade and the latter species is also transferred to Helicascus. A key to Helicascus species is provided

Biohydrogen Production by Antarctic Psychrotolerant Klebsiella sp. ABZ11

Lower temperature biohydrogen production has always been attractive, due to the lower energy requirements. However, the slow metabolic rate of psychrotolerant biohydrogen-producing bacteria is a common problem that affects their biohydrogen yield. This study reports on the improved substrate synthesis and biohydrogen productivity by the psychrotolerant Klebsiella sp. strain ABZ11, isolated from Antarctic seawater sample. The isolate was screened for biohydrogen production at 30°C, under facultative anaerobic condition. The isolate is able to ferment glucose, fructose and sucrose with biohydrogen production rate and yield of 0.8 mol/l/h and 3.8 mol/g, respectively at 10 g/l glucose concentration. It also showed 74% carbohydrate uptake and 95% oxygen uptake ability, and a wide growth temperature range with optimum at 37°C. Klebsiella sp. ABZ11 has a short biohydrogen production lag phase, fast substrate uptake and is able to tolerate the presence of oxygen in the culture medium. Thus, the isolate has a potential to be used for lower temperature biohydrogen production process

Isoprene hotspots at the Western Coast of Antarctic Peninsula during MASEC′16

Isoprene (C5H8) plays an important role in the formation of surface ozone (O3) and the secondary organic aerosol (SOA) which contributed to the climate change. This study aims to determine hourly distribution of tropospheric isoprene over the Western Coast of Antarctic Peninsula (WCAP) during the Malaysian Antarctic Scientific Expedition Cruise 2016 (MASEC′16). In-situ measurements of isoprene were taken using a custom-built gas chromatography with photoionization detector, known as iDirac. Biological parameters such as chlorophyll a (chl-a) and particulate organic carbon (POC) were compared to the in-situ isoprene measurements. Significant positive correlation was observed between isoprene and POC concentrations (r2 = 0.67, p < 0.001), but not between isoprene and chl-a. The hotspots of isoprene over maritime Antarctic were then were investigated using NAME dispersion model reanalysis. Measurements showed that isoprene mixing ratio were the highest over region of King George Island, Deception Island and Booth Island with values of ∼5.0, ∼0.9 and ∼5.2 ppb, respectively. Backward trajectory analysis showed that air masses may have lifted the isoprene emitted by marine algae. We believe our findings provide valuable data set of isoprene estimation over the under sampled WCAP. © 2018 Elsevier B.V. and NIP