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A TAXONOMIC STUDY OF THE GENUS PADINA (DICTYOTALES, PHAEOPHYCEAE) INCLUDING THE DESCRIPTIONS OF FOUR NEW SPECIES FROM JAPAN, HAWAII, AND THE ANDAMAN SEA(1)

Win NN, Hanyuda T, Arai S, Uchimura M, Prathep A, Draisma SG, et al.

J Phycol, 2011 Oct;47(5):1193-209.
PMID: 27028247 DOI: 10.1111/j.1529-8817.2011.01054.x

A taxonomic study of the genus Padina from Japan, Southeast Asia, and Hawaii based on morphology and gene sequence data (rbcL and cox3) resulted in the recognition of four new species, that is, Padina macrophylla and Padina ishigakiensis from Ryukyu Islands, Japan; Padina maroensis from Hawaii; and Padina usoehtunii from Myanmar and Thailand. All species are bistratose and morphologically different from one another as well as from any known taxa by a combination of characters relating to degree of calcification; the structure, position, and arrangement of hairlines (HLs) and reproductive sori; and the presence or absence of rhizoid-like groups of hairs and an indusium. Molecular phylogenetic analyses demonstrated a close relationship between P. ishigakiensis, P. macrophylla, P. maroensis, and Padina australis Hauck. The position of P. usoehtunii, however, was not fully resolved, being either sister to a clade comprising the other three new species and P. australis in the rbcL tree or more closely related to a clade comprising several other recently described species in the cox3 tree. The finding of the four new species demonstrates high species diversity particularly in southern Japan. The following characters were first recognized here to be useful for species delimitation: the presence or absence of small rhizoid-like groups of hairs on the thallus surface, structure and arrangement of HLs on both surfaces either alternate or irregular, and arrangement of the alternating HLs between both surfaces in equal or unequal distance. The evolutionary trajectory of these and six other morphological characters used in species delineation was traced on the phylogenetic tree.
Fulltext Optimised spectral effects of programmable LED arrays (PLA)s on bioelectricity generation from algal-biophotovoltaic devices

Ng FL, Phang SM, Lan BL, Kalavally V, Thong CH, Chong KT, et al.

Sci Rep, 2020 09 30;10(1):16105.
PMID: 32999346 DOI: 10.1038/s41598-020-72823-9

The biophotovoltaic cell (BPV) is deemed to be a potent green energy device as it demonstrates the generation of renewable energy from microalgae; however, inadequate electron generation from microalgae is a significant impediment for functional employment of these cells. The photosynthetic process is not only affected by the temperature, CO2 concentration and light intensity but also the spectrum of light. Thus, a detailed understanding of the influences of light spectrum is essential. Accordingly, we developed spectrally optimized light using programmable LED arrays (PLA)s to study the effect on algae growth and bioelectricity generation. Chlorella is a green microalga and contains chlorophyll-a (chl-a), which is the major light harvesting pigment that absorbs light in the blue and red spectrum. In this study, Chlorella is grown under a PLA which can optimally simulate the absorption spectrum of the pigments in Chlorella. This experiment investigated the growth, photosynthetic performance and bioelectricity generation of Chlorella when exposed to an optimally-tuned light spectrum. The algal BPV performed better under PLA with a peak power output of 0.581 mW m-2 for immobilized BPV device on day 8, which is an increase of 188% compared to operation under a conventional white LED light source. The photosynthetic performance, as measured using pulse amplitude modulation (PAM) fluorometry, showed that the optimized spectrum from the PLA gave an increase of 72% in the rETRmax value (190.5 μmol electrons m-2 s-1), compared with the conventional white light source. Highest algal biomass (1100 mg L-1) was achieved in the immobilized system on day eight, which translates to a carbon fixation of 550 mg carbon L-1. When artificial light is used for the BPV system, it should be optimized with the light spectrum and intensity best suited to the absorption capability of the pigments in the cells. Optimum artificial light source with algal BPV device can be integrated into a power management system for low power application (eg. environment sensor for indoor agriculture system).
Fulltext Publisher Correction: Electronic Properties of Synthetic Shrimp Pathogens-derived DNA Schottky Diodes

Rizan N, Yew CY, Niknam MR, Krishnasamy J, Bhassu S, Hong GZ, et al.

Sci Rep, 2018 Apr 12;8(1):6009.
PMID: 29651139 DOI: 10.1038/s41598-018-24116-5

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Fulltext Electronic Properties of Synthetic Shrimp Pathogens-derived DNA Schottky Diodes

Rizan N, Yew CY, Niknam MR, Krishnasamy J, Bhassu S, Hong GZ, et al.

Sci Rep, 2018 01 17;8(1):896.
PMID: 29343758 DOI: 10.1038/s41598-017-18825-6

The exciting discovery of the semiconducting-like properties of deoxyribonucleic acid (DNA) and its potential applications in molecular genetics and diagnostics in recent times has resulted in a paradigm shift in biophysics research. Recent studies in our laboratory provide a platform towards detecting charge transfer mechanism and understanding the electronic properties of DNA based on the sequence-specific electronic response, which can be applied as an alternative to identify or detect DNA. In this study, we demonstrate a novel method for identification of DNA from different shrimp viruses and bacteria using electronic properties of DNA obtained from both negative and positive bias regions in current-voltage (I-V) profiles. Characteristic electronic properties were calculated and used for quantification and further understanding in the identification process. Aquaculture in shrimp industry is a fast-growing food sector throughout the world. However, shrimp culture in many Asian countries faced a huge economic loss due to disease outbreaks. Scientists have been using specific established methods for detecting shrimp infection, but those methods do have their significant drawbacks due to many inherent factors. As such, we believe that this simple, rapid, sensitive and cost-effective tool can be used for detection and identification of DNA from different shrimp viruses and bacteria.
In vitro and in silico cholinesterase inhibitory potential of metabolites from Laurencia snackeyi (Weber-van Bosse) M. Masuda

Palaniveloo K, Ong KH, Satriawan H, Abdul Razak S, Suciati S, Hung HY, et al.

3 Biotech, 2023 Oct;13(10):337.
PMID: 37701628 DOI: 10.1007/s13205-023-03725-6

Alzheimer's disease (AD) is a neurodegenerative disease that causes deterioration in intelligence and psychological activities. Yet, till today, no cure is available for AD. The marine environment is an important sink of bioactive compounds with neuroprotective potential with reduced adverse effects. Recently, we collected the red algae Laurencia snackeyi from Terumbu Island, Malaysia which is known to be rich in halogenated metabolites making it the most sought-after red algae for pharmaceutical studies. The red alga was identified based on basic morphological characteristics, microscopic observation and chemical data from literature. The purplish-brown algae was confirmed a new record. In Malaysia, this species is poorly documented in Peninsular Malaysia as compared to its eastern continent Borneo. Thus, this study intended to investigate the diversity of secondary metabolites present in the alga and its cholinesterase inhibiting potential for AD. The extract inhibited both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with IC50 values of 14.45 ± 0.34 μg mL-1 and 39.59 ± 0.24 μg mL-1, respectively. Subsequently, we isolated the synderanes, palisadin A (1), aplysistatin (2) and 5-acetoxypalisadin B (3) that was not exhibit potential. Mass spectrometry analysis detected at total of 33 additional metabolites. The computational aided molecular docking using the AChE and BChE receptors on all metabolites shortlisted 5,8,11,14-eicosatetraynoic acid (31) and 15-hydroxy-1-[2-(hydroxymethyl)-1-piperidinyl]prost-13-ene-1,9-dione (42) with best inhibitory properties, respectively with the lowest optimal combination of S-score and RMSD values. This study shows the unexplored potential of marine natural resources, however, obtaining sufficient biomass for detailed investigation is an uphill task. Regardless, there is a lot of potential for future prospects with a wide range of marine natural resources to study and the incorporation of synthetic chemistry, in vivo studies in experimental design.
SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-023-03725-6.
Fulltext The impact of local surface changes in Borneo on atmospheric composition at wider spatial scales: coastal processes, land-use change and air quality

Pyle JA, Warwick NJ, Harris NR, Abas MR, Archibald AT, Ashfold MJ, et al.

Philos Trans R Soc Lond B Biol Sci, 2011 Nov 27;366(1582):3210-24.
PMID: 22006963 DOI: 10.1098/rstb.2011.0060

We present results from the OP3 campaign in Sabah during 2008 that allow us to study the impact of local emission changes over Borneo on atmospheric composition at the regional and wider scale. OP3 constituent data provide an important constraint on model performance. Treatment of boundary layer processes is highlighted as an important area of model uncertainty. Model studies of land-use change confirm earlier work, indicating that further changes to intensive oil palm agriculture in South East Asia, and the tropics in general, could have important impacts on air quality, with the biggest factor being the concomitant changes in NO(x) emissions. With the model scenarios used here, local increases in ozone of around 50 per cent could occur. We also report measurements of short-lived brominated compounds around Sabah suggesting that oceanic (and, especially, coastal) emission sources dominate locally. The concentration of bromine in short-lived halocarbons measured at the surface during OP3 amounted to about 7 ppt, setting an upper limit on the amount of these species that can reach the lower stratosphere.