Green and sustainable antibiofouling coatings: A review

Marine biofouling, the unwanted accumulation of living organisms on man-made structures is worsening every year. Biofouling in marine environment usually occurs in any wetted surface, submerged for a period of time in the seawater. This phenomenon happens in few stages started with conditioning and followed by attachment and colonization. Marine biofouling is a highly cost problem which requires unnecessary waste of financial source especially in fuel consumption and production time as well as safety problems. The currently used antibiofouling paint is reported to be highly toxic and threatening the marine organisms. The most commonly used antibiofouling agents are biocide-based such as the tributyl-n-Tin (TBT), Sea Nine 211, Irgarol 1051, Diuron and the copper-based. The well-developed coating companies such as Hempel USA, SeaCoat Technology, Nippon Paint and many more has started their involvement in making the earths greener by introducing the non-biocide coating that is claimed to be as good as the biocide based antibiofouling coatings. Although the paints did not clearly state the antibiofouling agents used to replace biocide, the paints introduced are however, still has its own drawbacks. The secondary metabolites extractedfrom natural products as a defence mechanism is a potential green antibiofouling agent. Apart of its lower toxicity, natural products are also biodegradable. Further study on development of sustainable antibiofouling coating is crucial. This paper intended to review available green and sustainable antifouling compound used as paint or coating. The effectiveness and toxicity of the antifoulant will be critically reviewed

Relationship between Market Competition and Green Supply Chain Management Practices in Manufacturing Industry

There is a growing market and institutional demands for companies to implement green practices to produce environment friendly products and services. Therefore, more companies are integrating the green practices into their operations, which have increased the market competition. In order to improve their competitiveness in the market, companies are forced to adapt to changing market requirements by implementing practices that could differentiate themselves, such as green supply chain management (GSCM). This study aims to understand the relationship between market competition and GSCM practices among manufacturing companies in Penang and Johor, Malaysia. Data gathered from a survey among the companies were analyzed using descriptive and correlation analysis. The results revealed that the level of market competition in the manufacturing companies’ business environment and the implementation of GSCM practices were relatively moderate. A Spearman’s correlation analysis show that market competition had a moderate positive relationship with all GSCM practices studied, namely green purchasing, product eco-design, cooperation with customers, reverse logistics and internal environmental management. The findings highlight the role of market competition in promoting environment friendly behavior in manufacturing industry. In addition, they also show that more should be done by the industry to improve the sustainability of their supply chain practices

Phytochemical diversity of Clinacanthus nutans extracts and their bioactivity correlations elucidated by NMR based metabolomics

Clinacanthus nutans is a medicinal herb and a traditional remedy for herpes viral infection, cancer, and diabetes mellitus. Despite its popular use, there is limited information on the chemical constituents and their relationship with the bioactivities of the herb. The choice of drying and extraction methods will greatly influence the metabolite profile and the bioactivities of an herbal extract. In order to maximize retention of the original chemical profile of the herb and quality assurance, optimization of processing methods is needed. Using nuclear magnetic resonance (NMR) based metabolomics approach, we have carried out a discriminative analysis of the metabolite profiles of the leaves and stems of the herb when different drying (air, oven, and freeze) and extraction (soaking and sonication) methods were used and correlated the metabolite profiles with the total phenolic content (TPC), antioxidant and α-glucosidase inhibitory activities. Identification of primary and secondary metabolites was performed using 1D- and 2D-NMR techniques as well as ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS). Results showed that the leaf extracts, which were richer in phenolic compounds and terpenoids, showed significantly higher bioactivities compared to the stem extracts. Several newly reported compounds in the herb, identified using tandem mass spectrometry, included gendarucin A, a gendarucin A isomer, 3,3-di-O-methylellagic acid, ascorbic acid, and two isomeric oxoprolinates. From the NMR metabolomics analysis, the PLS biplot model indicated that the presence of some phenolics compounds, terpenoids, and sulfur-containing glucosides in the oven and air dried leaf extracts are the main components responsible for the antioxidant and α-glucosidase inhibitory activities. This study has provided additional information on the chemistry and biology of the herb that may be useful in future development phytomedicinal preparations of C. nutans

Elemen Eko Kritik Dalam Puisi “Permintaan Alam” Karya A. Halim Ali

Manusia dan alam sekitar sentiasa berinteraksi antara satu dengan yang lain. Aktiviti manusia yang berlaku secara seimbang mempu mengekalkan kelestarian alam. Namun begitu, sekiranya aktiviti manusia berlaku secara tidak terkawal akan meyebabkan berlaku kemusnahan sacara besar-besaran terhadap alam ini. Justeru kajian mengupas dan menganalisis elemen-elemen eko kritik yang terdapat dalam puisi “Permintaan Alam” karya A. Halim Ali. Puisi ini dimuatkan dalam antologi puisi “Permintaan Alam” yang merupakan salah sebuah sajak dalam kumpulan puisi sulung penyair yang diterbitkan pada tahun 2000. Kajian ini menggunakan reka bentuk kualitatif dengan mengaplikasikan pendekatan analisis kandungan untuk mengenal pasti elemen-elemen eko kritik dalam puisi yang dipilih. Dapatan kajian menunjukkan terdapat empat tema utama eko kritik dalam puisi ini, iaitu kesan pemanasan global dan perubahan iklim, kemusnahan kepelbagaian biodiversiti, kemusnahan ekosistem lautan dan kemusnahan habitat flora dan fauna akibat proses pembandaran dan aktiviti perindustrian yang tidak terkawal. Dapatan kajian juga menunjukkan wujudnya elemen kritikan, kebimbangan dan keprihatinan penyair terhadap isu alam sekitar yang disuarakan melalui penggunaan metafora, simbolisme dan perlambangan. Dalam puisi ini, penyair menyuarakan kebimbangan dan kritikan dengan menggunakan perlambangan permohonan daripada alam agar manusia menyediakan semula makanan, menggantikan tumbuha-tumbuhan dan mengembalikan habitat flora dan fauna yang telah mengalami kemusnahan akibat aktiviti manusia yang tidak terkawal. Secara keseluruhannya, kajian telah berjaya membuktikan terdapat suntikan elemen eko kritik dalam genre puisi Melayu yang selama ini lebih dikaitkan dengan ciri-ciri estetika. Hasil kajian diharap dapat memperkayakan korpus ilmu dalam bidang kajian eko kritik sastera tempatan

Development of simple and cost effective method for arsenic (III) removal

In the present study, eight locally available low cost adsorbents (raw and heat treated) have been screening for its capability to remove As(III). The shale sedimentary rock (SSR) was selected as a good adsorbent based on high As(III) removal. The activation of adsorbent was carried out by heat (250 - 550°C) and acid treatment (0.1 - 1 M H2SO4) in order to chose the best treatment method for As(III) removal. Sorption experiments were conducted to examine the effect of initial As(III) concentration, contact time and initial pH on As(III) removal by SSR. Results show that, only by heating the adsorbent at 500°C for 1h, 0.2 g of SSR adsorbent capable to reduce the residual As(III) concentration below than maximum concentration limit (10μg/L)for initial concentration from 100 to 700 μg/L and optimum pH ranges between 3 to 9 after 24 h of contact time.The adsorption data fits well with Langmuir isotherm and yielded Langmuir mono layer capacity of 0.987 mgAs(III)/g of SSR at pH 7. The SSR adsorbent has been successfully used for the removal of arsenic from seven real groundwater samples containing arsenic in the range of 20.2 to 697.34 μg/L with 86.73 to 97.86% removal efficiency

Metabolites and biological activities of Phoenix dactylifera L. pulp and seeds: a comparative MS and NMR based metabolomics approach

Phoenix dactylifera L. (date palm) is an essential agricultural crop in many arid regions of the world and has been used in traditional medicine to treat illnesses. Extracts of P. dactylifera are reported to possess valuable pharmacological attributes. This study aims to evaluate the metabolite profiles of date pulp and seeds utilizing 1H nuclear magnetic resonance (NMR) and ultra-high performance liquid chromatography mass spectrometry (UHPLC-MS) techniques. The nitric oxide (NO) inhibitory activity of extracts were assessed using stimulated RAW 264.7 cells along with the NO and DPPH scavenging activities, and total phenolic contents (TPC). Multivariate data analysis (MVDA) was used to examine the similarities and variation between samples of date palms. Principal component analysis (PCA) score plots showed distinct clustering of date seeds and pulp. Examination of the S-plot analysis revealed that ascorbic acid, catechin and glucose were the metabolites that significantly discriminated the date pulp group from the seed group. The seeds of Deglet dates demonstrated significantly higher NO inhibitory and DPPH scavenging activities, with IC50 values of 107.99 μg/mL and 12.58 μg/mL, respectively. The metabolites that prominently contributed to the observed bioactivities included catechin, ascorbic acid and serine. The proposed metabolic pathway indicated that higher amounts of several metabolites are present in date seeds than in date pulp. The presented data suggest possible applications of seeds and pulp of P. dactylifera that may increase the productivity of this fruit crop

Two extraction-free reverse transcription loop-mediated isothermal amplification assays for detection of SARS-CoV-2

Abstract Background Current assays for detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rely on time consuming, costly and laboratory based methods for virus isolation, purification and removing inhibitors. To address this limitation, we propose a simple method for testing RNA from nasopharyngeal swab samples that bypasses the RNA purification step. Methods In the current project, we have described two extraction-free reverse transcription loop-mediated isothermal amplification (RT-LAMP) assays for the detection of SARS-CoV-2 by using E gene and RdRp gene as the targets. Results Here, results showed that reverse transcription loop-mediated isothermal amplification assays with 88.4% sensitive (95% CI: 74.9–96.1%) and 67.4% sensitive (95% CI: 51.5–80.9%) for E gene and RdRp gene, respectively. Conclusion Without the need of RNA purification, our developed RT-LAMP assays for direct detection of SARS-CoV-2 from nasopharyngeal swab samples could be turned into alternatives to qRT-PCR for rapid screening

Clinical testing on SARS-CoV-2 swab samples using reverse-transcription loop-mediated isothermal amplification (RT-LAMP)

Abstract Background High cost of commercial RNA extraction kits limits the testing efficiency of SARS-CoV-2. Here, we developed a simple nucleic acid extraction method for the detection of SARS-CoV-2 directly from nasopharyngeal swab samples. Methods A pH sensitive dye was used as the end point detection method. The obvious colour changes between positive and negative reactions eliminates the need of other equipment. Results Clinical testing using 260 samples showed 92.7% sensitivity (95% CI 87.3–96.3%) and 93.6% specificity (95% CI 87.3–97.4%) of RT-LAMP. Conclusions The simple RNA extraction method minimizes the need for any extensive laboratory set-up. We suggest combining this simple nucleic acid extraction method and RT-LAMP technology as the point-of care diagnostic tool