The aim of this study is to investigate the technical feasibility of converting macroalgae cellulosic residue (MCR) into bioethanol. An attempt was made to present a novel, environmental friendly and economical pretreatment process that enhances enzymatic conversion of MCR to sugars using Dowex (TM) Dr-G8 as catalyst. The optimum yield of glucose reached 99.8% under the optimal condition for solid acid pretreatment (10%, w/v biomass loading, 4%, w/v catalyst loading, 30min, 120°C) followed by enzymatic hydrolysis (45FPU/g of cellulase, 52CBU/g of β-glucosidase, 50°C, pH 4.8, 30h). The yield of sugar obtained was found more superior than conventional pretreatment process using H2SO4 and NaOH. Biomass loading for the subsequent simultaneous saccharification and fermentation (SSF) of the pretreated MCR was then optimized, giving an optimum bioethanol yield of 81.5%. The catalyst was separated and reused for six times, with only a slight drop in glucose yield.
Superparamagnetic magnetite nanocomposites (Fe3O4-NCs) were successfully synthesized, which comprised of montmorillonite (MMT) as matrix support, Kappaphycus alvarezii (SW) as bio-stabilizer and Fe3O4 as filler in the composites to form MMT/SW/Fe3O4-NCs. Nanocomposite with 0.5 g Fe3O4 (MMT/SW/0.5Fe3O4) was selected for anticancer activity study because it revealed high crystallinity, particle size of 7.2 ± 1.7 nm with majority of spherical shape, and Ms = 5.85 emu/g with negligible coercivity. Drug loading and release studies were carried out using protocatechuic acid (PCA) as the model for anticancer drug, which showed 19% and 87% of PCA release in pH 7.4 and 4.8, respectively. Monolayer anticancer assay showed that PCA-loaded MMT/SW/Fe3O4 (MMT/SW/Fe3O4-PCA) had selectivity towards HCT116 (colorectal cancer cell line). Although MMT/SW/Fe3O4-PCA (0.64 mg/mL) showed higher IC50 than PCA (0.148 mg/mL) and MMT/SW/Fe3O4 (0.306 mg/mL, MMT/SW/Fe3O4-PCA showed more effective killing towards tumour spheroid model generated from HCT116. The IC50 for MMT/SW/Fe3O4-PCA, MMT/SW/Fe3O4 and PCA were 0.132, 0.23 and 0.55 mg/mL, respectively. This suggests the improved penetration efficiency and drug release of MMT/SW/Fe3O4-PCA towards HCT116 spheroids. Moreover, concentration that lower than 2 mg/mL MMT/SW/Fe3O4-PCA did not result any hemolysis in human blood, which suggests them to be ideal for intravenous injection. This study highlights the potential of MMT/SW/Fe3O4-NCs as drug delivery agent.
Candida is the most frequent common causes of invasive fungal infections and associated with high morbidity and mortality. Most of available antifungal agents have side effects. This opened up new avenues to investigate the antifungal efficacy of active extracts from marine algae. So the aim of this study was to evaluate the protective and the curative effect of Ulva fasciata extract against an invasive candidiasis in mice and to study its underlying mechanism. The active ingredients of Ulva fasciata extract were evaluated using HPLC and GC/MS. Fifty mice were included in current work, and the level of inflammatory markers; Interleukin (IL)-4, IL-12, Interferon-gamma (IFN-γ) and Tumor necrosis factor-alpha (TNF-α) were determined using ELISA kits. Hematological, biochemical and oxidative stress parameters were determined using commercial kits. Moreover, the histopathological examinations were carried on liver, kidney and spleen for all groups. The results obtained showed that treatment with U. fasciata either before or after Candida infection significantly improved the hematological, biochemical alterations and antioxidant status caused by this infection. Furthermore, the U. fasciata reduced histopathological changes induced by Candida as well as it could increase the expression of IL-12 and IFN-γ while minimized the expression of TNF-α and IL-4 in all infected mice compared to infected untreated mice. These data propose that U. fasciata can ameliorate inflammatory reactions related to Candida albicans cytotoxicity via its ability to augment cellular antioxidant defenses by its active compounds.
Brown seaweeds are rich source of functional polysaccharides that exhibit various bioactivities. However, Malaysian seaweeds are under-utilised, leading to low revenue throughout the supply chain of the seaweed industry. The aims of this study were to extract the functional polysaccharides, namely fucoidan (F), laminaran (L) and alginate (A) from Malaysian brown seaweeds (Sargassum polycystum, Turbinaria ornata and Padina boryana) and subsequently evaluate the properties of the extracted polysaccharides. P. boryana recorded the significantly (p ≤ 0.05) highest carbohydrate content (74.78 ± 1.63%) with highest fucoidan yield (Fpad = 1.59 ± 0.16%) while T. ornata contained significantly (p ≤ 0.05) highest alginate yield (Atur = 105.19 ± 3.45%). Water activities of these extracted polysaccharides varied from 0.63-0.71 with average score of browning indexes (~40). Fourier transform infrared (FTIR) spectroscopy analysis demonstrated that the extracted polysaccharides exhibited similar spectral pattern of spectra with the respective standards. Meanwhile, laminaran extracts showed the significantly highest (p ≤ 0.05) total phenolic contents (Lsar = 43.29 ± 0.43 mgGAE/g) and superoxide anion scavenging activity (Lsig = 21.7 ± 3.6%). On the other hand, the significantly highest (p ≤ 0.05) DPPH scavenging activity was recorded in alginate with Asar at 85.3 ± 0.8%. These findings reported the properties and bioactivities of natural polysaccharides from Malaysian brown seaweeds that revealed the potential to develop high-value functional ingredients from Malaysian brown seaweeds.
Edible seaweeds are valuable because of their organoleptic properties and complex polysaccharide content. A study was conducted to investigate the potential of dried edible seaweed extracts, its potential phenolic compounds and alginates for α-amylase inhibitory effects. The kinetics of inhibition was assessed in comparison with acarbose. The methanol extract of Laminaria digitata and the acetone extract of Undaria pinnatifida showed inhibitory activity against α-amylase, IC50 0.74 ± 0.02 mg/ml and 0.81 ± 0.03 mg/ml, respectively; both showed mixed-type inhibition. Phenolic compound, 2,5-dihydroxybenzoic acid was found to be a potent inhibitor of α-amylase with an IC50 value of 0.046 ± 0.004 mg/ml. Alginates found in brown seaweeds appeared to be potent inhibitors of α-amylase activity with an IC50 of (0.075 ± 0.010-0.103 ± 0.017) mg/ml, also a mixed-type inhibition. Overall, the findings provide information that crude extracts of brown edible seaweeds, phenolic compounds and alginates are potent α-amylase inhibitors, thereby potentially retarding glucose liberation from starches and alleviation of postprandial hyperglycaemia.
Magnetic iron oxide nanoparticles (Fe3O4 MNPs) are among the most useful metal nanoparticles for multiple applications across a broad spectrum in the biomedical field, including the diagnosis and treatment of cancer. In previous work, we synthesized and characterized Fe3O4 MNPs using a simple, rapid, safe, efficient, one-step green method involving reduction of ferric chloride solution using brown seaweed (Sargassum muticum) aqueous extract containing hydroxyl, carboxyl, and amino functional groups mainly relevant to polysaccharides, which acts as a potential stabilizer and metal reductant agent. The aim of this study was to evaluate the in vitro cytotoxic activity and cellular effects of these Fe3O4 MNPs. Their in vitro anticancer activity was demonstrated in human cell lines for leukemia (Jurkat cells), breast cancer (MCF-7 cells), cervical cancer (HeLa cells), and liver cancer (HepG2 cells). The cancer cells were treated with different concentrations of Fe3O4 MNPs, and an MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay was used to test for cytotoxicity, resulting in an inhibitory concentration 50 (IC50) value of 23.83±1.1 μg/mL (HepG2), 18.75±2.1 μg/mL (MCF-7), 12.5±1.7 μg/mL (HeLa), and 6.4±2.3 μg/mL (Jurkat) 72 hours after treatment. Therefore, Jurkat cells were selected for further investigation. The representative dot plots from flow cytometric analysis of apoptosis showed that the percentages of cells in early apoptosis and late apoptosis were increased. Cell cycle analysis showed a significant increase in accumulation of Fe3O4 MNP-treated cells at sub-G1 phase, confirming induction of apoptosis by Fe3O4 MNPs. The Fe3O4 MNPs also activated caspase-3 and caspase-9 in a time-response fashion. The nature of the biosynthesis and therapeutic potential of Fe3O4 MNPs could pave the way for further research on the green synthesis of therapeutic agents, particularly in nanomedicine, to assist in the treatment of cancer.
Malaria, the most widespread mosquito-borne disease, affects 350-500 million people each year. Eco-friendly control tools against malaria vectors are urgently needed. This research proposed a novel method of plant-mediated synthesis of silver nanoparticles (AgNP) using a cheap seaweed extract of Ulva lactuca, acting as a reducing and capping agent. AgNP were characterized by UV-vis spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The U. lactuca extract and the green-synthesized AgNP were tested against larvae and pupae of the malaria vector Anopheles stephensi. In mosquitocidal assays, LC50 values of U. lactuca extract against A. stephensi larvae and pupae were 18.365 ppm (I instar), 23.948 ppm (II), 29.701 ppm (III), 37.517 ppm (IV), and 43.012 ppm (pupae). LC50 values of AgNP against A. stephensi were 2.111 ppm (I), 3.090 ppm (II), 4.629 ppm (III), 5.261 ppm (IV), and 6.860 ppm (pupae). Smoke toxicity experiments conducted against mosquito adults showed that U. lactuca coils evoked mortality rates comparable to the permethrin-based positive control (66, 51, and 41%, respectively). Furthermore, the antiplasmodial activity of U. lactuca extract and U. lactuca-synthesized AgNP was evaluated against CQ-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of Plasmodium falciparum. Fifty percent inhibitory concentration (IC50) values of U. lactuca were 57.26 μg/ml (CQ-s) and 66.36 μg/ml (CQ-r); U. lactuca-synthesized AgNP IC50 values were 76.33 μg/ml (CQ-s) and 79.13 μg/ml (CQ-r). Overall, our results highlighted out that U. lactuca-synthesized AgNP may be employed to develop newer and safer agents for malaria control.
Edible seaweeds are a good source of antioxidants, dietary fibers, essential amino acids, vitamins, phytochemicals, polyunsaturated fatty acids, and minerals. Many studies have evaluated the gelling, thickening and therapeutic properties of seaweeds when they are used individually. This review gives an overview on the nutritional, textural, sensorial, and health-related properties of food products enriched with seaweeds and seaweed extracts. The effect of seaweed incorporation on properties of meat, fish, bakery, and other food products were highlighted in depth. Moreover, the positive effects of foods enriched with seaweeds and seaweed extracts on different lifestyle diseases such as obesity, dyslipidemia, hypertension, and diabetes were also discussed. The results of the studies demonstrated that the addition of seaweeds, in powder or extract form, can improve the nutritional and textural properties of food products. Additionally, low-fat products with less calories and less saturated fatty acids can be prepared using seaweeds. Moreover, the addition of seaweeds also affected the health properties of food products. The results of these studies demonstrated that the health value, shelf-life and overall quality of foods can be improved through the addition of either seaweeds or seaweed extracts.
This study was designed to investigate the comparative in vivo cardiovascular protective effects of red, green, and brown tropical seaweeds, namely, Kappaphycus alvarezii (or Eucheuma cottonii), Caulerpa lentillifera, and Sargassum polycystum, in rats fed on high-cholesterol/high-fat (HCF) diets. Male Sprague-Dawley rats (weighing 260-300 g) on the HCF diet had significantly increased body weight, plasma total cholesterol (TC), plasma low-density lipoprotein cholesterol (LDL-C), plasma triglycerides (TG), lipid peroxidation, and erythrocyte glutathione peroxidase (GSH-Px) and superoxide dismutase levels after 16 weeks. Supplementing 5% seaweeds to HCF diet significantly reduced plasma TC (-11.4% to -18.5%), LDL-C (-22% to -49.3%), and TG (-33.7% to -36.1%) levels and significantly increased HDL-C levels (16.3-55%). Among the seaweeds, S. polycystum showed the best anti-obesity and blood GSH-Px properties, K. alvarezii showed the best antihyperlipemic and in vivo antioxidation effects, and C. lentillifera was most effective at reducing plasma TC. All seaweeds significantly reduced body weight gain, erythrocyte GSH-Px, and plasma lipid peroxidation of HCF diet rats towards the values of normal rats.
In the present study, we evaluated the effect of brown seaweeds Sargassum muticum methanolic extract (SMME), against MCF-7 and MDA-MB-231 breast cancer cell lines proliferation. This algae extract was also evaluated for reducing activity and total polyphenol content. The MTT assay results indicated that the extracts were cytotoxic against breast cancer cell lines in a dose-dependent manner, with IC50 of 22 μg/ml for MCF-7 and 55 μg/ml for MDA-MB-231 cell lines. The percentages of apoptotic MCF-7-treated cells increased from 13% to 67% by increasing the concentration of the SMME. The antiproliferative efficacy of this algal extract was positively correlated with the total polyphenol contents, suggesting a causal link related to extract content of phenolic acids. Cell cycle analysis showed a significant increase in the accumulation of SMME-treated cells at sub-G1 phase, indicating the induction of apoptosis by SMME. Further apoptosis induction was confirmed by Hoechst 33342 and AO/PI staining. Also SMME implanted in vivo into fertilized chicken eggs induced dose-related antiangiogenic activity in the chorioallantoic membrane (CAM). Our results imply a new insight on the novel function of Sargassum muticum polyphenol-rich seaweed in cancer research by induction of apoptosis, antioxidant, and antiangiogenesis effects.
Cosmetics are widely used by people around the world to protect the skin from external stimuli. Consumer preference towards natural cosmetic products has increased as the synthetic cosmetic products caused adverse side effects and resulted in low absorption rate due to the chemicals' larger molecular size. The cosmetic industry uses the term "cosmeceutical", referring to a cosmetic product that is claimed to have medicinal or drug-like benefits. Marine algae have gained tremendous attention in cosmeceuticals. They are one of the richest marine resources considered safe and possessed negligible cytotoxicity effects on humans. Marine algae are rich in bioactive substances that have shown to exhibit strong benefits to the skin, particularly in overcoming rashes, pigmentation, aging, and cancer. The current review provides a detailed survey of the literature on cosmeceutical potentials and applications of algae as skin whitening, anti-aging, anticancer, antioxidant, anti-inflammation, and antimicrobial agents. The biological functions of algae and the underlying mechanisms of all these activities are included in this review. In addition, the challenges of using algae in cosmeceutical applications, such as the effectiveness of different extraction methods and processing, quality assurance, and regulations concerning extracts of algae in this sector were also discussed.