Recent Advances of Marine Sponge-Associated Microorganisms as a Source of Commercially Viable Natural Products

Marine Biotechnology - Many industrially significant compounds have been derived from natural products in the environment. Research efforts so far have contributed to the discovery of beneficial...     

Comparative Study on Biological Activities and Chemical Profiling of Mushroom (Pleurotus pulmonarius (Fr.) Quel.) Cultured on Lignocellulosic Agro Wastes

The relevance of the lignocellulosic substrate in the cultivation of mushrooms has lent support to the exploration of several lignocellulosic agro wastes. This study was, thus, aimed at the evaluation of durian peel as an alternative substrate for more sustainable mushroom cultivation and climate change mitigation. The secondary metabolites and biological activities of both aqueous and organic mushroom (Pleurotus pulmonarius (Fr.) Quel.) extract cultured on durian peel and rubberwood sawdust substrate were compared using GCMS, LCMS as well as various biological assays (cytotoxicity, antimicrobial and antioxidant activities). Mushroom extracts from durian peel substrates possess remarkable biological activities. The results showed that the aqueous extracts had poor antimicrobial activities. The organic extracts were more active against cancer cells than the aqueous extracts, while the aqueous extracts were more potent as antioxidants than the organic extracts. Overall, the mushroom extract from the durian substrate was the most effective except against A549 and SW948, while the aqueous extract from the durian substrate was the most effective against the A549 cancer cell lines with 29.53±2.39 % inhibition. On the other hand, the organic mushroom extract from the sawdust substrate was the most effective against SW948 with 60.24±2.45 % inhibition. Further studies, however, are needed to elucidate the molecular mechanism of action of P. pulmonarius extracts against cancer cell proliferation and the effect of the substrates on the nutritional composition, secondary metabolites, and other biological activities of P. pulmonarius extracts.     

Insecticide resistance in dengue vectors from hotspots in Selangor,Malaysia

BackgroundIn Malaysia, dengue remains a top priority disease and usage of insecticides is the main method for dengue vector control. Limited baseline insecticide resistance data in dengue hotspots has prompted us to conduct this study. The present study reports the use of a map on the insecticide susceptibility status of Aedes aegypti and Aedes albopictus to provide a quick visualization and overview of the distribution of insecticide resistance.Method and resultsThe insecticide resistance status of Aedes populations collected from 24 dengue hotspot areas from the period of December 2018 until June 2019 was proactively monitored using the World Health Organization standard protocol for adult and larval susceptibility testing was conducted, together with elucidation of the mechanisms involved in observed resistance. For resistance monitoring, susceptibility to three adulticides (permethrin, deltamethrin, and malathion) was tested, as well as susceptibility to the larvicide, temephos. Data showed significant resistance to both deltamethrin and permethrin (pyrethroid insecticides), and to malathion (organophosphate insecticide) in all sampled Aedes aegypti populations, while variable resistance patterns were found in the sampled Aedes albopictus populations. Temephos resistance was observed when larvae were tested using the diagnostic dosage of 0.012mg/L but not at the operational dosage of 1mg/L for both species.ConclusionThe present study highlights evidence of a potential threat to the effectiveness of insecticides currently used in dengue vector control, and the urgent requirement for insecticide resistance management to be integrated into the National Dengue Control Program.     

Hevea brasiliensis latex proteomics: a review of analytical methods and the way forward

Journal of Plant Research - Natural rubber or latex from the Hevea brasiliensis is an important commodity in various economic sectors in today’s modern society. Proteins have been detected in...     

Plagioneurin B,a potent isolated compound induces apoptotic signalling pathways and cell cycle arrest in ovarian cancer cells

Plagioneurin B belongs to acetogenin group has well-established class of compounds. Acetogenin group has attracted worldwide attention in the past few years due their biological abilities as inhibitors for several types of tumour cells. Plagioneurin B was isolated via conventional chromatography and tested for thorough mechanistic apoptosis activity on human ovarian cancer cells (CAOV-3). Its structure was also docked at several possible targets using Autodock tools software. Our findings showed that plagioneurin B successfully inhibits the growth of CAOV-3 cells at IC₅₀ of 0.62 µM. The existence of apoptotic bodies, cell membrane blebbing and chromatin condensation indicated the hallmark of apoptosis. Increase of Annexin V-FITC bound to phosphatidylserine confirmed the apoptosis induction in the cells. The apoptosis event was triggered through the extrinsic and intrinsic pathways via activation of caspases 8 and 9, respectively. Stimulation of caspase 3 and the presence of DNA ladder suggested downstream apoptotic signalling were initiated. Further confirmation of apoptosis was conducted at the molecular levels where up-regulation in Bax, as well as down-regulation of Bcl-2, Hsp-70 and survivin were observed. Plagioneurin B was also seen to arrest CAOV-3 cells cycle at the G2/M phase. Docking simulation of plagioneurin B with CD95 demonstrated that the high binding affinity and hydrogen bonds formation may explain the capability of plagioneurin B to trigger apoptosis. This study is therefore importance in finding the effective compound that may offer an alternative drug for ovarian cancer treatment.     

Correction to: Hevea brasiliensis latex proteomics: a review of analytical methods and the way forward

Journal of Plant Research -