Sargassum polycystum (S. polycystum) is a brown macroalga with a high phytochemical content, making it a nutritious and bioactive food source. However, information on factors contributing to health benefits, like antioxidants and cytotoxicity, is less explored for Malaysian S. polycystum. In this study, three extracts of S. polycystum were characterized using a combination of analytical techniques. Despite similar carbohydrate content across all extracts, water extract exhibited the highest protein [21.90 ± 1.01 albumin equivalent (μg/mg)] and phenolic [7.73 ± 1.95 gallic acid equivalent (μg/mg)] contents. However, it displayed the lowest antioxidant and anticancer activities [half-maximal inhibitory concentration (IC50) of > 2000 μg/mL]. Interestingly, ethanolic extract demonstrated the strongest scavenging activity (IC50 of 397.90 ± 20.43 μg/mL) and selective anticancer activity against MCF7 breast cancer cells (IC50 of 338.63 ± 48.98 μg/mL). Untargeted metabolomic profiling confirmed the differences in the chemical composition of the extracts. Subsequently, correlation and docking analyses were used to identify the potential bioactive compounds within the extracts. The ethanolic extract is a rich source of these bioactive compounds with superior antioxidant and anticancer properties, highlighting the need for further research on its potential utility in the food industry.
Due to the restrictions in accessing research laboratories and the challenges in providing proper storage and transportation of cells during the COVID-19 pandemic, having an effective and feasible mean to solve these challenges would be of immense help. Therefore, we developed a 3D culture setting of cancer cells using alginate beads and tested its effectiveness in different storage and transportation conditions. The viability and proliferation of cancer cells were assessed using trypan blue staining and quantitative CCK-8 kit, respectively. The developed beads allowed cancer cells survival up to 4 weeks with less frequent maintenance measures such as change of the culture media or subculture of cells. In addition, the recovery of cancer cells and proliferation pattern were significantly faster with better outcomes in the developed 3D alginate beads compared to the standard cryopreservation of cells or the 2D culture conditions. The 3D alginate beads also supported the viability of cells while the shipment at room temperature for a duration of up to 5 days with no humidity or CO2 support. Therefore, 3D culture in alginate beads can be used to store or ship biological cells with ease at room temperature with minimal preparations.
Clinacanthus nutans (C. nutans) is a plant in tropical Asia with proven biological activities. The optimized extraction method of C. nutans crude polysaccharide (CNP) uses water in the presence of an ultrasound-assisted mechanical method (UL_CNP). However, the use of UL_CNP for the synthesis and optimization of silver nanoparticles (AgNP), particularly their anticancer and photocatalytic properties, remains unexplored. Hence, this research aimed to employ a green method using UL_CNP and silver nitrate to produce AgNP (UL_AgNP) with a small size and assess its potential toxicity, anticancer, and photocatalytic activities. The synthesis condition was optimized using the Box-Behnken design method. The synthesized UL_AgNP showed the surface plasmon resonance peak at 458 nm. The optimized synthesis condition produced spherically shaped UL_AgNP with a size of 5.21 ± 1.92 nm and a zeta potential of -26.33 ± 0.93 mV. An X-ray diffraction analysis exhibited intense Bragg's reflection peaks at (111), (200), (220), and (311), having a face-centered cubic structure of AgNP. Attenuated total reflectance-Fourier-transform infrared spectroscopy and energy-dispersive X-ray spectroscopy further confirmed the presence of silver in the synthesized UL_AgNP. The brine shrimp lethality test of UL_AgNP reported a lethal concentration 50 value of <7.8 μg/mL after 24 h. The UL_AgNP exhibited antiproliferative activity against MCF-7 cells with a half-maximal inhibitory concentration value of 4.96 ± 0.31 μg/mL by inducing S-phase cell cycle arrest, apoptotic effect, and reduction of cell migration. Furthermore, UL_AgNP proved its efficient photocatalytic activity against methylene blue dye (50.22 % ± 0.06 %, after 10 min at a concentration of 50 μg/mL). Therefore, the UL_AgNP exhibited promising antiproliferative activity against MCF-7 cells, highlighting their potential as a therapeutic agent. Further investigations are needed to elucidate the precise mechanism of their action.
As per the WHO, colorectal cancer (CRC) caused around 935,173 deaths worldwide in 2020 in both sexes and at all ages. The available anticancer therapies including chemotherapy, radiotherapy and anticancer drugs are all associated with limited therapeutic efficacy, adverse effects and low chances. This has urged to emerge several novel therapeutic agents as potential therapies for CRC including synthetic and natural materials. Orally administrable and targeted drug delivery systems are attractive strategies for CRC therapy as they minimize the side effects, enhance the efficacy of anticancer drugs. Nevertheless, oral drug delivery till today faces several challenges like poor drug solubility, stability, and permeability. Various oral nano-based approaches and targeted drug delivery systems have been developed recently, as a result of the ability of nanoparticles to control the release of the encapsulant, drug targeting and reduce the number of dosages administered. The unique physicochemical properties of chitosan polymer assist to overcome oral drug delivery barriers and target the colon tumour cells. Chitosan-based nanocarriers offered additional improvements by enhancing the stability, targeting and bioavailability of several anti-colorectal cancer agents. Modified chitosan derivatives also facilitated CRC targeting through strengthening the protection of encapsulant against acidic and enzyme degradation of gastrointestinal track (GIT). This review aims to provide an overview of CRC pathology, therapy and the barriers against oral drug delivery. It also emphasizes the role of nanotechnology in oral drug targeted delivery system and the growing interest towards chitosan and its derivatives. The present review summarizes the relevant works to date that have studied the potential applications of chitosan-based nanocarrier towards CRC treatment.
The synergistic bioactive effect of polyphenols can enhance the development of functional foods to prevent chronic diseases such as cancer. Curcumin and quercetin have been shown to possess anticancer properties. The combination of curcumin and quercetin has been shown to provide synergistic effects against cancer cell proliferation. The prospect of exhibiting a synergistic antitumor effect is to target a multi-pathway approach, reduce dosage, and minimize potential side effects. However, their effectiveness is limited by poor bioavailability. Nanoscale delivery systems are promising strategies for the delivery of polyphenols. Nevertheless, many of these nanomaterials are yet to be commercialized owing to their lack of versatility or manufacturing costs. Thus, developing a formulation that responds to body conditions is a great challenge and would provide a better way to orally administer polyphenols. Therefore, this study aimed to develop a dual-responsive disulfide-linked core-shell nanohybrid for oral delivery and targeted release of polyphenols in the colon. The nanohybrid had monodispersed structures with a size of 9.5 nm), surface area of > 700 m2/g, and zeta potential of - 30.71 ± 0.71 mV. The polyphenols were encapsulated into the nanohybrid in their amorphous state, with a loading capacity of 20.49%. The coating enhanced the release of polyphenols into the intestinal fluid, potentially improving their delivery to the colon. The nanohybrid demonstrated a better anticancer effect than the free polyphenols against HT29 cancer cells. This study explores the use of a dual-sensitive alginate-coated mesoporous silica nanohybrid as a carrier for the enhanced delivery of polyphenols.
Therapeutic gene editing is becoming more feasible with the emergence of the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein (Cas) system. However, the successful implementation of CRISPR/Cas9-based therapeutics requires a safe and efficient in vivo delivery of the CRISPR components, which remains challenging. This study presents successful preparation, optimization, and characterization of alginate nanoparticles (ALG NPs), loaded with two CRISPR plasmids, using electrospray technique. The aim of this delivery system is to edit a target gene in another plasmid (green fluorescent protein (GFP)). The effect of formulation and process variables were evaluated. CRISPR ALG NPs showed mean size and zeta potential of 228 nm and -4.42 mV, respectively. Over 99.0% encapsulation efficiency was achieved while preserving payload integrity. The presence of CRISPR plasmids in the ALG NPs was confirmed by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy. The tests revealed that the nanoparticles were cytocompatible and successfully introduced the Cas9 transgene in HepG2 cells. Nanoparticles-transfected HepG2 was able to edit its target plasmid by introducing double-strand break (DSB) in GFP gene, indicating the bioactivity of CRISPR plasmids encapsulated in alginate nanoparticles. This suggests that this method is suitable for biomedical application in vitro or ex vivo. Future investigation of theses nanoparticles might result in nanocarrier suitable for in vivo delivery of CRISPR/Cas9 system.
The performance of water as a heat transfer medium in numerous applications is limited by its effective thermal conductivity. To improve the thermal conductivity of water, herein, we report the development and thermophysical characterization of novel metal-metal-oxide-carbon-based ternary-hybrid nanoparticles (THNp) GO-TiO2-Ag and rGO-TiO2-Ag. The results indicate that the graphene oxide- and reduced graphene oxide-based ternary-hybrid nanoparticles dispersed in water enhance the base fluid (H2O) thermal conductivity by 66% and 83%, respectively, even at very low concentrations. Mechanisms contributing to this significant enhancement are discussed. The experimental thermal conductivity is plotted against the existing empirical hybrid thermal conductivity correlations. We found that those correlations are not suitable for the metal-metal-oxide-carbon combinations, calling for new thermal conductivity models. Furthermore, the rheological measurements of the nanofluids display non-Newtonian behavior, and the viscosity reduces with the increase in temperature. Such behavior is possibly due to the non-uniform shapes of the ternary-hybrid nanoparticles.
Malaysian seaweed, particularly Sargassum polycystum, has potential for alginate production, yet an extraction protocol for this seaweed remains lacking. This study aimed to optimize the extraction process to maximize alginate yield while characterizing the physicochemical properties of the extracted alginate and its potential applications. An alkali-based extraction method was employed, with key parameters, including alkali concentration, extraction temperature, and time, carefully optimized to yield 30.17 ± 0.76 % (g alginate/100 g dry seaweed biomass) of alginate. Sodium alginate extracted from Sargassum polycystum has a viscosity-average molecular weight of 4.73 ± 0.001 × 104 g/mol and an M/G ratio of 2.87. The physicochemical properties and biochemical composition of the extracted alginate revealed its capacity to be utilized as a natural antioxidant. An alginate-based nanohybrid for polyphenol delivery was developed to explore the potential applications of extracted alginate. This nanohybrid showed favorable properties (hydrodynamic particle size: 415 nm, PDI: 0.3, zeta potential: -44.7 mV), high encapsulation (80.13 %), and loading efficiency (19.21 ± 1.69 %). Alginate coating on the nanohybrid protected polyphenol from premature release, significantly enhancing its antioxidant activity. These findings suggest that alginate extracted from Malaysian Sargassum polycystum could be a valuable natural material for developing controlled-release delivery systems.