Evaluating seasonal variations of fecal coliform colonization in Magallana hongkongensis and Crassostrea rhizophorae: A preliminary study of oyster quality grown in Hong Kong aquacultural farms.

The objective of this research is to investigate the spatial and temporal patterns of bacteriological quality in raw oysters sampled from different aquacultural farms located in Aberdeen Typhoon Shelter, Carp Gates, Lau Fau Shan, Ma Wan, and Mui Wo in Hong Kong. Magallana hongkongensis and Crassostrea rhizophorae were collected and analyzed for fecal coliforms. Throughout the 13-month monitoring period, all samples had generally high bacterial loads, ranging from 1.4 × 107 cfu/g to 8.9 × 107 cfu/g and exceeded the guideline suggested by the HKSAR government (i.e. 700 MPN/100 g). Besides, a linear regression analysis showed that the amount of fecal coliforms in raw oysters had strong correlations (p < 0.05) to the monthly rainfall records throughout the monitoring period. Such findings illustrate the high loading of pathogenic microorganisms in the tissue of oysters which represent a potential threat of people contracting foodborne diseases.

An assessment of heavy metal contamination in the marine soil/sediment of Coles Bay Area, Svalbard, and Greater Bay Area, China: a baseline survey from a rapidly developing bay.

The objective of this research is to investigate the pollution levels of tin (Sn), arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), mercury (Hg), and zinc (Zn) of soil/sediment taken in Coles Bay Area (CBA), Svalbard, and Great Bay Area (GBA), China, in an attempt to evaluate the pollution potential related to recent development in the areas. A total of 150 soil/sediment samples were collected in each location. Heavy metal concentrations were detectable levels at all sites and the values of Cd of all soil/sediment samples were higher than Dutch Target and Intervention Values. Heavy metal concentration in soil/sediment was further analyzed by principal component analysis (PCA). It was revealed that three components were found in two studying sites and contributed 60.2% and 75.9% of variations to reflect soil/sediment quality in CBA and GBA, respectively. Based on the results of KMO (0.52) and Bartlett's test (p < 0.000), there are 32.1%, 15.6%, and 11.1% and 39.45%, 19.01%, and 17.52% of the variance in the first, second, and third component explained that the metal concentration of Pb, Cd, and Sn was highly correlated with the soil/sediment quality in CBA and GBA, respectively. Among these three heavy metals, Cd concentration was the common dominant factor to affect soil/sediment quality in these two study sites. It is recommended that investigation of the sources of pollution (either point or non-point source) during CBA or GBA development and management together with consideration of abiotic (soil)-biotic (organisms) interactions should be taken into account when choosing suitable remediation strategies in the future.

Feasibility of Sijunzi Tang (Chinese medicine) to enhance protein disulfide isomerase activities for reactivating malate dehydrogenase deactivated by polycyclic aromatic hydrocarbons.

The objective of this research is to investigate the enzymatic activities between protein disulfide isomerase (PDI) found in animals and plants and the properties found in a commonly used Chinese medicine called Sijunzi Tang. During the investigation, PDI, which is a monomer with a molecular mass of 57.0 kDa, was used to reactivate malate dehydrogenase (MDH). However, with the interference of polycyclic aromatic hydrocarbons (PAHs), evidence indicates that such chemicals are carcinogenic, mutagenic, and toxic to humans. The enzymatic activity of PDI found in animal's liver and plant was 1657 folds of purification; 0.284 unit/mg of enzyme activity, and 5694.4 folds of purification; 1.00 unit/mg of enzyme activity, respectively. PDI extracted in treated animal and plant tissue revealed 2.40% and 80.44% of regaining MDH enzymatic activity, respectively. Although in its initial phase of investigation, it is assumed that the properties found in Sijunzi Tang can help regain enzymatic activity in those affected by xenobiotic substances, thus, making it a potential ingredient in assisting with PDI functions.

Behavioural toxicity studies of Cyclope neritea and Nassarius mutabilis exposed to polycyclic aromatic hydrocarbons.

The objective of the work was to study behavioural change of Cyclope neritea (sea snail) and Nassarius mutabilis (land snail) upon exposure to different levels of PAHs. Snail's behaviour was translated and expressed in Behavioural State Score (BSS) where the score ranged from "0" to "5" points refers to the ascending level of locomotion of a snail. A significant difference was found in snail's behaviour in 25.0 mg/L than in 0.5 mg/L with p value smaller than 0.01. BSS scores appear most frequent on the treatment and control group were 5 (61.5-64.5%) and 2 (41.0-45.0%), respectively. Intersex behaviour was found in all species (i.e. the same sex was grouped together) regardless of PAH concentrations. This is the first reported to study the behavioural change of snail sampled in Hong Kong area when exposed to PAHs. Further studies should be carried on the impact of snail's behaviour exposure on each congener in the family of PAHs.

The potential of Mikania micrantha (Chinese creeper) to hyperaccumulate heavy metals in soil contaminated by electronic waste.

The objective of this study is to investigate the contributions of Mikania micrantha (chinese creeper) to remediate heavy metal pollutants present in an e-waste-contaminated soil. Different proportions of e-waste soil (0%, 25%, 50%, 75%, and 100% w/w) planted with Cynodon dactylon together with the test species were prepared for testing relative seed germination (RSG), relative root growth (RRG), and germination index (GI) tests. A significant higher value of GI (77.8%) was found in M. micrantha than that of the other species when planting in 100% e-waste-contaminated soil. A significant correlation (< 0.05) was found between heavy metal concentration and germination assays in M. micrantha. A significant decrease in heavy metal concentration of the polluted soil after the experiment indicated that biomolecule development studies to determine the aggregate benefit of M. micrantha for phytoremediation remain to be studied in future.