Streptococcus pneumoniae is a major pathogen causing pneumonia with over 2 million deaths annually, especially in young children and the elderly. To date, at least 98 different pneumococcal capsular serotypes have been identified. Currently, the vaccines for prevention of S. pneumoniae infections are the 23-valent pneumococcal polysaccharide-based vaccine (PPV23) and the pneumococcal conjugate vaccines (PCV10 and PCV13). These vaccines only cover some pneumococcal serotypes and are unable to protect against non-vaccine serotypes and unencapsulated S. pneumoniae. This has led to a rapid increase in antibiotic-resistant non-vaccine serotypes. Hence, there is an urgent need to develop new, effective, and affordable pneumococcal vaccines, which could cover a wide range of serotypes. This review discusses the new approaches to develop effective vaccines with broad serotype coverage as well as recent development of promising pneumococcal vaccines in clinical trials. New vaccine candidates are the inactivated whole-cell vaccine strain (Δpep27ΔcomD mutant) constructed by mutations of specific genes and several protein-based S. pneumoniae vaccines using conserved pneumococcal antigens, such as lipoprotein and surface-exposed protein (PspA). Among the vaccines in Phase 3 clinical trials are the pneumococcal conjugate vaccines, PCV-15 (V114) and 20vPnC. The inactivated whole-cell and several protein-based vaccines are either in Phase 1 or 2 trials. Furthermore, the recent progress of nanoparticles that play important roles as delivery systems and adjuvants to improve the performance, as well as the immunogenicity of the nanovaccines, are reviewed.

The fluid mosaic model of Singer and Nicolson in 1972 shows how proteins are embedded in membranes. To elucidate the interactions between proteins and the surrounding lipids, stearic acid (SA) and bovine serum albumin (BSA) were used as lipid-protein components to mimic the normal membrane bilayer environment using the Langmuir-Blodgett technique. Surface pressure (π)-molecular area (A) isotherms were recorded for the SA monolayer in the presence of BSA on water. The mixed monolayer was successfully transferred onto an oxidized silicon wafer and imaged by tapping mode atomic force microscopy (AFM). Miscibility, compressibility and thermodynamic stability of the mixed system were examined. A large negative deviation of Aex, together with the minimum value of ΔGex, was observed when the mole fraction of BSA (XBSA) was 0.8, indicating this to be the most stable mixture. In a compressibility analysis, XBSA was observed at below 50 mN m-1, denoting a liquid-expanded phase and showing the occurrence of a strong interaction of SA with BSA molecules in this phase. AFM observations supported the quantitative data indicating that BSA was strongly attracted onto the membrane surface as predicted.

BackgroundApplication of natural resources from the marine environment in the cosmeceutical industry is gaining great attention.AimThis study pursues to discover the cosmeceutical potential of two Malaysian algae, Sargassum sp. and Kappaphycus sp. by determining their antioxidant capacity and assessing the presence of their secondary metabolites with cosmeceutical potential using non‐targeted metabolite profiling.MethodsMetabolite profiling using Quadrupole Time‐of‐Flight (Q‐TOF) liquid chromatography‐mass spectrometry (LC–MS) in the Electrospray Ionization (ESI) mode resulted in 110 putative metabolites in Sargassum sp. and 47 putative metabolites in Kappaphycus sp. and were grouped according to their functions. To the best of our knowledge, the bioactive compounds of both algae have not been studied in any great detail. This is the first report to explore their cosmeceutical potential.ResultsSix antioxidants were detected in Sargassum sp., including fucoxanthin, (3S, 4R, 3'R)‐4‐Hydroxyalloxanthin, enzacamene N‐stearoyl valine, 2‐hydroxy‐hexadecanoic acid, and metalloporphyrins. Meanwhile, three antioxidants detected in Kappahycus sp., namely Tanacetol A, 2‐fluoro palmitic acid and idebenone metabolites. Three antioxidants are found in both algae species, namely, 3‐tert‐Butyl‐5‐methylcatechol, (−)‐isoamijiol, and (6S)‐dehydrovomifoliol. Anti‐inflammatory metabolites such as 5(R)‐HETE, protoverine, phytosphingosine, 4,5‐Leukotriene‐A4, and 5Z‐octadecenoic acid were also found in both species. Sargassum sp. possesses higher antioxidant capacity as compared to Kappahycus sp. which may be linked to its number of antioxidant compounds found through LC–MS.ConclusionsHence, our results conclude that Malaysian Sargassum sp. and Kappaphycus sp. are potential natural cosmeceutical ingredients as we aim to produce algae cosmeceutical products using native algae.

Marine natural products are a good source of antioxidants due to the presence of a wide range of bioactive compounds. Accumulating evidence proves the potential use of seaweed-derived ingredients in skincare products. This study aims to evaluate the ultraviolet (UV) protective activity of the ethanol and water extracts of Padina australis. As the preliminary attempt for this discovery, the total phenolic content (TPC) and total flavonoid content (TFC) were measured, followed by the in vitro antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and reducing the power to shed light on its bioactivity. The UVB protective activity was examined on HaCaT human keratinocyte cells. The findings of this study reveal that the P. australis ethanol extract serves as a promising source of antioxidants, as it exhibits stronger antioxidant activities compared with the water extract in DPPH and the reducing power assays. The P. australis ethanol extract also demonstrated a higher level of total phenolic (76 mg GAE/g) and flavonoid contents (50 mg QE/g). Meanwhile, both the ethanol (400 µg/mL) and water extracts (400 µg/mL) protected the HaCaT cells from UVB-induced cell damage via promoting cell viability. Following that, LCMS analysis reveals that the P. australis ethanol extract consists of sugar alcohol, polysaccharide, carotenoid, terpenoid and fatty acid, whereas the water extract contains compounds from phenol, terpenoid, fatty acid, fatty alcohol and fatty acid amide. In summary, biometabolites derived from P. australis have diverse functional properties, and they could be applied to the developments of cosmeceutical and pharmaceutical products.

In this study, the implication of employing blended solvents during the synthesis of glycerol dioleates (GDO) using Candida antartica lipase was investigated. GDO is an example of diacylglycerol (DAG) that comprises two oleic acid chains esterified to one glycerol backbone. A model system consisting of glycerol and oleic acid was used to determine the effects of different solvent systems exhibiting various viscosities and polarities on conversion, yield, and selectivity of glycerol oleates. The study was carried out at different temperatures. The rheological properties of solventless, acetone, tert-butanol, and blended solvents systems exhibited Newtonian flow behavior, and their viscosities decreased at elevated temperatures. As compared to GMO and GTO, GDO synthesis showed the highest yield (70%) and selectivity (54%) at 40 °C within 2 h in the reaction medium containing blended solvents of tert-butanol/acetone. The rate of reaction and productivity of GDO in tert-butanol/acetone were achieved at 0.27 M h −1 and 0.48 M h −1 , respectively. The tested systems were found to be endothermic and in a disordered manner at all investigated ranges of temperatures studied. The esterification reaction was found to be spontaneous, and the Gibbs energy decreased with increasing temperature.