It is expected that 84% of the global energy demands will be met through fossil fuels in 2030 due to increasing energy needs. However, due to their impact on the environment through the emission of anthropogenic green house gases, biofuels were introduced as alternative sources of energy. Biofuels of plant origin for the transport sector proved to be controversial due to competition for food production, fertile land and expensive production processes. As a secondary alternative, microalgae such as Scenedesmus obliquus, Chlorella vulgaris and Nannochloropsis sp. were found to be suitable candidates for liquid biofuels production. This review describes the production of transportation liquid biofuels from plant biomass and microalgae. Information is provided on how the controversies related to plant biomass lead to the use of algal biomass. The production processes involved in both generations are discussed and highlighted. Furthermore, details on the production of secondary products such as pigments, feed additives and valuable secondary metabolites are also provided.

Fluid chemistry and microbial community patterns in chimney habitats were investigated in two hydrothermal fields located at the Central Indian Ridge. Endmember hydrothermal fluid of the Solitaire field, located ~3 km away from the spreading center, was characterized by moderately high temperature (307°C), Cl depletion (489 mm), mildly acidic pH (≥4.40), and low metal concentrations (Fe ≤ 105 μm and Mn = 78 μm). Chloride depletion indicates that the subseafloor source fluid had undergone phase separation at temperatures higher than ~390°C while the metal depletion was likely attributable to fluid alteration occurring at a venting temperature of around 307°C. These different temperature conditions suggested from fluid chemistry might be associated with an off‐spreading center location of the field that allows subseafloor fluid cooling prior to seafloor discharge. The microbial community in the chimney habitat seemed comparable to previously known patterns in typical basalt‐hosted hydrothermal systems. Endmember hydrothermal fluid of the Dodo field, standing on center of the spreading axis, was characterized by high H₂ concentration of 2.7 mm. The H₂ enrichment was likely attributable to fresh basalt–fluid interaction, as suggested by the nondeformed sheet lava flow expansion around the vents. Thermodynamic calculation of the reducing pyrite–pyrrhotite–magnetite (PPM) redox buffer indeed reproduced the H₂ enrichment. The quantitative cultivation test revealed that the microbial community associated with the hydrothermal fluid hosted abundant populations of (hyper)thermophilic hydrogenotrophic chemolithoautotrophs such as methanogens. The function of subseafloor hydrogenotrophic methanogenic populations dwelling around the H₂‐enriched hydrothermal fluid flows was also inferred from the ¹³C‐ and D‐depleted signature of CH₄ in the collected fluids. It was observed that the hydrothermal activity of the Dodo field had ceased until 2013.

Piton du Milieu (PdM) impounding reservoir is suspected to be eutrophic based on the elevated level of orthophosphate and nitrate. Water supplies from three adjacent rivers are primarily thought to contribute to the nutrient enrichment of the reservoir. It is also suspected that there is leaching of orthophosphate, nitrate and organic matter into the rivers during rainfall events and also as a result of anthropogenic activities within the catchment area. The aim of this study was to ascertain the impact of nutrient loading on the water quality of PdM water and on the population of freshwater microalgae in the reservoir. The enumeration and identification of algae from PdM were performed by differential interference contrast microscopy. Dissolved oxygen (DO) and pH were determined by electrometric methods, whereas nutrient levels, silica and total organic carbon (TOC) were determined by instrumentation techniques. Annual mean orthophosphate, nitrate and total organic carbon input from the three feeders within the catchment area of PdM reached levels as high as 0.09 mg/L, 0.4 mg/L and 2.62 ppm respectively. Over a 12-month period, mean TOC concentration in the reservoir was 2.32 ppm while the mean algal cell count was 4601 cells/mL. The dominant algal species identified were Oscillatoria, Cyclotella, Navicula and Cosmarium. This study highlights the trophic state of the reservoir water and clearly points to the need for constant monitoring in order to avoid the occurrence of an impending harmful algal bloom.

Background: Fusarium species, a group of economically destructive phytopathogens, are poorly studied in Mauritius where agriculture holds much significance. Furthermore, the increasing popularity of organic farming has prompted interest in alternatives to chemical fungicides. Methods: After gaining an overview of Fusarium prevalence in Mauritius fields through a survey, the pathogen was isolated from infected crops and identified based on morphological and molecular characteristics. Methanol and water extracts were then prepared from Melia azedarach, Ocimum gratissimum, cinnamon and cloves before determining their phytochemical profiles. Additionally, the antioxidant and antifungal effects of different concentrations of aqueous extracts were assessed. Results: The isolate was confirmed as Fusarium oxysporum, and cloves inhibited its growth by up to 100%, especially at 60 and 90 g/L, with the results being significantly higher than those of the synthetic fungicide mancozeb. Over 50% inhibition was also noted for cinnamon and Ocimum gratissimum, and these effects could be linked to the flavonoids, phenols and terpenoids in the extracts. Conclusion: This study presented the aqueous extracts of cloves, cinnamon and Ocimum gratissimum as potential alternatives to chemical fungicides. It also confirmed the prevalence of Fusarium infection in Mauritius fields, thereby highlighting the need for additional studies on the pathogen.

A novel yeast-like species was isolated from the rhizosphere of tobacco root collected in Guizhou province, China. Sequence analysis of the large subunit (LSU) rDNA gene indicates that the isolate represents a novel species and most closely related to Meira siamensis. The phylogenetic analysis based on the Internal Transcribed Spacer (ITS) rDNA gene also confirmed the placement of the novel species within Meira. However, the novel species differs from M. siamensis by 9.1% bp difference in the LSU rDNA sequence region and also in terms of physiological characteristics as compared to other species. This species is proposed as M. nicotianae sp. nov. Co-incubation of M. nicotianae strain CY-1 and tobacco plantlets demonstrates that this fungal strain can promote growth of tobacco plant. Scanning electron micrographs and other morphological illustrations along with phylogenies are presented in this paper.

Botryosphaeriaceous fungi cause stem blight, canker and dieback in woody plants. During a survey on the fungal pathogens associated with blueberries in China, 135 blighted, cankered or dead blueberry branches were collected from Fujian and Shandong Provinces. Based on the morphological characterization and phylogenetic analyses of a concatenated ITS rDNA, tef1-α, TUB, and RPB2 loci, five new species of Lasiodiplodia, viz., L. clavispora, L. fujianensis, L. henanica, L. nanpingensis and L. paraphysoides were recognized. Detailed descriptions and illustrations, as well as multigene phylogenies, are provided in this paper. The diversity of plant pathogens on agriculturally and economically important plants is higher than anticipated.