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The purpose of this study was to assess the north coasts of the Egyptian Red Sea, including Ras Gharieb, Hurghada, Safaga and Qusier, by evaluating the heavy metal pollution in seawater and benthic flora and fauna in the winter and summer of 2016. The concentrations of heavy metals (Fe, Mn, Zn, Cu, Ni, Cd and Pb) were analysed with an atomic absorption spectrophotometer. The results revealed that the Fe levels in the seawater ranged from 7.86 and 27.95 µg l-1, while the Zn concentrations fell between 1.83 and 5.63 µg l-1. In contrast, the recorded values of Mn, Cu, Ni, Pb and Cd in the seawater were minimal at the study sites. Regarding the biota samples, Porifera species were more adaptable than others to an accumulation of most metals in their tissues. Furthermore, seaweeds and seagrasses demonstrated remarkable adaptation in highly polluted regions, especially those with high turbidity, landfilling, sedimentation and high eutrophication rates – much more than the benthic fauna. Our research highlights the critical need for strict regulation of metal emissions in these coastal regions.

The main objective of this study was to establish a human cell-based platform to assess the effects of sediment toxicity on oxidative damage and cell essential behaviour. Since sediment pollution has increased as a consequence of including but not limited to industrialisation, the contaminants accumulated in sediments have already led to human health concerns. The Hsinchu Science Park is one of the most prominent semiconductor manufacturing centres in the world, and the Ke-Ya River flows through Hsinchu Science Park and the Hsinchu urban district. Because semiconductor wastes potentially contribute to higher-than-normal rates of cancers, birth defects, and serious diseases, the quality assessment of the Ke-Ya River has prompted widespread concerns. While previous studies have shown an association between the degradation of fish populations and sediment pollutants, very little is known about the issues on human health. Herein, the effects of sediment from three sediment sampling sites of the Ke-Ya River on 11 different human cell lines were directly evaluated. The upstream represents the undeveloped zone, the middle-stream represents the household/industrial wastewater zone, and the downstream represents the accumulation zone. Our results indicated that the sediment pollution of the downstream Ke-Ya River was more cytotoxic than that of the middle stream and upstream. Downstream sediment extract (DSE) significantly increased reactive oxygen species (ROS) levels across all cell types. Accordingly, oxidative stress can trigger redox-sensitive pathways and alter essential biological processes such as cell viability, cell adhesion, and cell motility. Importantly, the MTT assay indicated that DSE significantly decreased the viability of brain, oral, lung, breast, liver, pancreatic, cervical, prostate, and colorectal cells. Furthermore, the adhesive ability and wound healing ability of most cells were greatly reduced in the presence of DSE compared to other conditions. Thus, this study shows the results of the first analyses completed on the sediment cytotoxicity in human cells, and stimulated ROS levels are crucial for cellular life. In future research, the detailed cause and effect mechanisms of the abundant ROS generated in DSE will be further investigated. We sincerely hope that our study provides a scientific basis for further investigations with a global perspective on public health challenges.

After decades of strict pollution control and municipal sewage treatment, the water quality of the Tanshui River increased significantly after pollution mitigation as indicated by the River Pollution Index (RPI). The pollution level of the estuarine region decreased from severe pollution to mostly moderately impaired. The most polluted waters are presently restricted to a flow track length between 15–35 km relative to the river mouth. From July 2011 to September 2012, four surveys of fish and benthic macroinvertebrates were conducted at 45 sampling sites around the Tanshui River basin. The pollution level of all the study area indicated by the RPI could also be explained by the Family Biotic Index (FBI) and Biotic Index (BI) from the benthic macroinvertebrate community, and the Index of Biotic Integrity (IBI) of the fish community. The result of canonical correlation analysis between aquatic environmental factors and community structure indicated that the community structure was closely related to the level of water pollution. Fish species richness in the estuarine area has increased significantly in recent years. Some catadromous fish and crustaceans could cross the moderate polluted water into the upstream freshwater, and have re-colonized their populations. The benthic macroinvertebrate community relying on the benthic substrate of the estuarine region is still very poor, and the water layer was still moderately polluted.

We used the mitochondria DNA COI (cytochrome c oxidase subunit I) sequence as a genetic marker to analyze the population genetic structure of two species of freshwater copepods, Neodiaptomus schmackeri (Poppe and Richard, 1892) and Mongolodiaptomus birulai (Rylov, 1922) from Taiwan. Four populations with 51 individuals of N. schmackeri and five populations with 65 individuals of M. birulai were included. We compared the nucleotide sequences of a 635-bp fragment of the COI gene of N. schmackeri and a 655-bp fragment of the COI gene of M. birulai, and eight and 14 unique haplotypes were recorded, respectively. Tseng-Wen reservoir and Wu-San-Tao reservoir are linked by a channel, and the gene flow between them was unrestricted (Fst = 0.058; Nm = 4.04; Fst, population differentiation parameter; Nm, the number of succesfull migrants per generation); the gene flow between all other populations of both species was restricted (Fst = 0.4–0.99; Nm = 0–0.37). Based on the COI gene diversification pattern, we suggest that most populations of N. schmackeri and M. birulai are isolated from each other. According to the neighbor-joining tree and the minimum spanning network (MSN), the species have similar metapopulation genetic structures. Genetic distance was not found to be correlated with geographical distance. The genetic diversification pattern was not shown to be comparable with geographical isolation owing to long-distance separation. The genetic structure of the present populations may result from serial extinction and redistribution of the populations formed in each reservoir relative to time. Human activity in the reservoirs with regards to water resource management and the fishery industry also exerts an effect on population redistribution.

During surveys on yeast diversity in forest soils from Taiwan and Thailand, ten yeast strains isolated from different samples were found to have similar molecular and physiological characteristics. Sequence analysis of small subunit (SSU) rDNA, the D1/D2 domain of large subunit (LSU) rDNA and internal transcribed spacer (ITS)-5.8S rDNA demonstrated that these strains were closely related to Scheffersomyces spartinae. The novel strains could be differentiated from S. spartinae by a 0.9 % sequence divergence (5 substitutions, 0 gaps) in the D1/D2 domain of LSU rDNA, a 1.5 % divergence (8 substitutions, 0 gaps) in the ITS-5.8S rDNA and a 0.7 % divergence (12 substitutions, 2 gaps) in the SSU rDNA. The novel strains also showed specific patterns of electrophoretic karyotypes that differed from that of S. spartinae. Therefore, a novel yeast species, Candida gosingica sp. nov., is proposed to accommodate these strains. The type strain SJ7S11T (=BCRC 23194T=CBS 11433T) was assigned and deposited in the Bioresource Collection and Research Center (BCRC), Food Industry Development and Research Institute, Hsinchu, Taiwan, and Centraalbureau voor Schimmelcultures (CBS), Utrecht, The Netherlands.

A new yeast species, Kazachstania wufongensis, is proposed in this paper based on six strains isolated from soil in Taiwan. The species may produce one to four ellipsoidal ascospores in each ascus, directly transformed from diploid cells. Genus assignment and distinction of the species from other recognized species of Kazachstania is based on morphological and physiological characteristics, and on phylogenetic analysis of nucleotide sequences of the D1/D2 domains of the large subunit (LSU) rRNA gene. Sequence analysis of the D1/D2 domains of the LSU rRNA gene reveals that K. wufongensis is a member of the Kazachstania exigua complex, and its phylogenetically closest relatives are K. exigua, K. barnettii, K. bulderi, and K. turicensis. The species can be further differentiated from the other phylogenetically related species based on internal transcribed spacer sequence and electrophoretic karyotype. Therefore, the new species Kazachstania wufongensis sp. nov. is proposed. The type strain of this new species, which was isolated from forest soil in Wufong, Hsinchu, Taiwan, is FN21S03(T) (=CBS 10886(T) = BCRC 23138(T)).

Seven yeast strains isolated from the soil in Northern Taiwan were identified as Kazachstania africana, Kazachstania exigua and Kazachstania yakushimaensis, based on morphological, physiological, and molecular characteristics. This discovery marked the first finding of this genus, which is represented by these three species, in Taiwan. The DNA sequences of the D1/D2 domain of the large subunit (LSU) rRNA genes were identical to or less than three nucleotides different from that of the respective type strains. In this paper, morphological, physiological and molecular characteristics of the strains representing these three species are described.

In the mountain area of Taiwan, we investigated 10 subpopulations of Neutrodiaptomus tumidus Kiefer 1937 living in isolated alpine ponds or lakes. We used mitochondrial DNA cytochrome C oxidase subunit I (COI) sequence as molecular marker to investigate the population genetic structure and their phylogeographical relationships. We obtained 179 sequences from 10 subpopulations and found 94 haplotypes. Nucleotide composition was AT-rich. Haplotype diversity (Hd) and nucleotide diversity (π) indicated significant genetic differences between subpopulations (Hd = 0.131 ~ 0.990; π = 0.0002 ~ 0.0084); genetic differentiation index (F st) and gene flow index (N m) also exhibited significant genetic diversification between subpopulations (F st = 0.334 ~ 0.997; N m = 0 ~ 1). Using Tajima’s D and Fu and Li’s D* and F* as neutrality tests, we found that the nucleotide variation within the population was consistent with the neutral theory except in the JiaLuoHu subpopulation. The JiaLuoHu subpopulation significantly deviated from the neutral theory and was speculated to have experienced a bottleneck effect. According to the phylogenetic tree, these alpine lake subpopulations could be divided into four phylogroups (northern region, Xueshan group, central region, and southwestern region). Xueshan group contains one subpopulation, DuRongTan, which is a unique group relative to other groups. It is close to northern group geographically but closer to southwestern group genetically. According to AMOVA, the major genetic variation came from different geographical distribution of subpopulations. Molecular clock estimates that the northern and southern regional divergence time was about 2.2 ~ 3.9 MYA, when the Central Mountain Range uplift (3 ~ 5 MYA) caused the population of N. tumidus to be segregated into northern and southern parts. Significant genetic divergence between each subpopulation of N. tumidus was found in this study. This result indicated the low dispersion ability of planktonic copepods with limited gene flow between each subpopulation.

The authors found five species of freshwater calanoids (Copepoda, Calanoida), in Taiwan, i.e., Sinocalanus laevidactylus, Pseudodiaptomus annandalei, Mongolodiaptomus birulai, Neutrodiaptomus tumidus, and Neodiaptomus schmackeri. S. laevidactylus and P. annandalei live in freshwater ponds near coastal areas. M. birulai, N. tumidus, and N. schmackeri primarily inhabit pools, ponds, reservoirs, and lakes. S. laevidactylus, P. annandalei, and N. schmackeri constitute new records of freshwater elements for the Taiwanese fauna. Allodiaptomus ueno, reported as Diaptomus ueno by Kikuchi (1936a) and Tropodiaptomus oryzanus reported by Kiefer (1937) were not found in our extensive collecting programme, and are believed to be now extinct in Taiwan.

A novel yeast species, Lachancea dasiensis sp. nov., is proposed in this paper based on two strains isolated from leaves and one strain from soil in Taiwan. The strains produce one or two spherical ascospores in each ascus, preceded by conjugation of individual cells. Genus assignment and distinction of the species from other recognized species of Lachancea are based on morphological and physiological characteristics and on phylogenetic analysis of nucleotide sequences of the D1/D2 domains of the large subunit (LSU) rRNA gene. Sequence analysis of the D1/D2 domains of the LSU rRNA gene reveals that the phylogenetically closest relatives of L. dasiensis sp. nov. are Lachancea thermotolerans and Lachancea waltii. The novel species could be differentiated from the latter two species based on electrophoretic karyotypes. The type strain of Lachancea dasiensis sp. nov. is SC5L02(T) (=CBS 10888(T) =BCRC 23139(T)), which was isolated from a leaf of Angiopteris lygodiifolia Rosenst. in Dasi, Taoyuan, Taiwan.

Nine anamorphic, ascomycetous yeast strains belonging to the Pichia anomala clade were recovered from forest soil in 2006 in Taiwan. The nine yeast strains represent four novel yeast species based on the sequences of their D1/D2 domain of the large subunit (LSU) rRNA gene and their physiological characteristics. The scientific names of Candida dajiaensis sp. nov., Candida yuanshanicus sp. nov., Candida jianshihensis sp. nov., and Candida sanyiensis sp. nov. are proposed for these novel yeast species. The type strains are C. dajiaensis SM11S03(T) (=CBS 10590(T)=BCRC 23099(T)), C. yuanshanicus SY3S02(T) (=CBS 10589(T)=BCRC 23100(T)), C. jianshihensis SM8S04(T) (=CBS 10591(T)=BCRC 23096(T)), and C. sanyiensis SA1S06(T) (=CBS 10592(T)=BCRC 23094(T)). Sequence analysis of the D1/D2 of the LSU rRNA gene revealed that the three species, C. dajiaensis, C. yuanshanicus and Pichia onychis, shared a separate branch in the phylogenetic tree, C. jianshihensis is phylogenetically related to Candida ulmi and Pichia alni, and the phylogenetically closest relative of C. sanyiensis is Pichia populi.

A new ascomycetous yeast species, Kazachstania jiainicus, is proposed based on two strains isolated from soil in Taiwan. The species is characterized by forming one or two globose spores in each ascus, fermenting glucose and galactose and assimilating few carbon and nitrogen compounds. Genus assignment and distinction of the strains from recognized species is based on ascosporulation and phylogenetic analysis of nucleotide sequences from domains D1/D2 of the large subunit (26S) rRNA gene. Sequence analysis showed that the species was phylogenetically related to the genus Kazachstania. The species was distinct from recognized species of Kazachstania on the basis of carbon and nitrogen assimilation patterns. Based on the characteristics described above, the species is recognized as a novel species of the genus Kazachstania, and the name Kazachstania jiainicus sp. nov. is proposed. The type strain is SF1S05T (=CBS10587T=NBRC 102655T=BCRC 23098T), which was isolated from soil in Jiain, Hualein, Taiwan.