Algal Extracts Research Articles

Green synthesis of ZnO nanoparticles using marine brown algae (Cystoseira) extract comprising sol–gel, and combustion techniques based on dye-sensitized solar cells application

The ZnO nanoparticles were synthesized using marine brown algae (Cystoseira) extract and calcination. For comparison, combustion, and sol–gel methods were employed to synthesize nanoparticles to use as material in dye-sensitized solar cells (DSSCs) photoanode. The produced nanoparticles were characterized using structural and morphological studies by FTIR, SEM, and XRD experiments, respectively. The results revealed that the net hexagonal crystal structure was achieved with a crystal size of less than 100 nm, good purity, spherical shape, and a suitable dimension for fabricating DSSCs. They exhibit enhanced properties due to the variation in their characteristics such as average size, size distribution, and morphology. The ZnO nanoparticles were used to fabricate the DSSCs by the doctor blade method, and the efficacy of each cell was evaluated using voltage–current measurement. The results were in good agreement with the characteristic curve of the commercialized DSSC. The best performance for the fabricated DSSCs was achieved using green synthesized ZnO nanoparticles, because of the influence of their morphology such as smaller crystal size, more grain boundaries, and bigger surface area. The cell’s solar-to-electricity conversion efficiency, short-circuit current, open-circuit voltage, and fill factor were measured as ∼1.13%, 3.8[Formula: see text]mA/cm2, 620[Formula: see text]mV, and 54.3%, respectively. The enhanced photovoltaic properties were ascribed to the flower-like morphological structures of the ZnO nanoparticles prepared using the green synthesis method.

Photoprotective and Anti-Aging Properties of the Apical Frond Extracts from the Mediterranean Seaweed Ericaria amentacea.

There is a growing interest in using brown algal extracts thanks to the bioactive substances they produce for adaptation to the marine benthic environment. We evaluated the anti-aging and photoprotective properties of two types of extracts (50%-ethanol and DMSO) obtained from different portions, i.e., apices and thalli, of the brown seaweed, Ericaria amentacea. The apices of this alga, which grow and develop reproductive structures during summer when solar radiation is at its peak, were postulated to be rich in antioxidant compounds. We determined the chemical composition and pharmacological effects of their extracts and compared them to the thallus-derived extracts. All the extracts contained polyphenols, flavonoids and antioxidants and showed significant biological activities. The hydroalcoholic apices extracts demonstrated the highest pharmacological potential, likely due to the higher content of meroditerpene molecular species. They blocked toxicity in UV-exposed HaCaT keratinocytes and L929 fibroblasts and abated the oxidative stress and the production of pro-inflammatory cytokines, typically released after sunburns. Furthermore, the extracts showed anti-tyrosinase and anti-hydrolytic skin enzyme activity, counteracting the collagenase and hyaluronidase degrading activities and possibly slowing down the formation of uneven pigmentation and wrinkles in aging skin. In conclusion, the E. amentacea apices derivatives constitute ideal components for counteracting sunburn symptoms and for cosmetic anti-aging lotions.

Spirulina platensis improves growth, oil content, and antioxidant activitiy of rosemary plant under cadmium and lead stress

In the present study, a pot experiment was conducted to investigate the response of rosemary (Rosmarinus officinalis L.) plants to foliar application of Spirulina platensis at 0.0, 0.1, 0.2, and 0.4%; soil irrigation with heavy metals (Cd nitrate, Pb acetate, and Cd + Pb, each at 100 ppm), and Spirulina platensis at 0.1% + heavy metals. Spirulina platensis significantly improved growth parameters, oil yield/fed, photosynthetic pigments, and activity of superoxide dismutase (SOD), glutathione reductase (GR), catalase (CAT), and polyphenol oxidase (PPO) with a maximum promoting effect at 0.2% algal extract. On the other hand, heavy metal stress reduced growth criteria, photosynthetic pigments, and oil yield, while, significantly increased levels of antioxidant enzymes (SOD, CAT, GR) and corresponding non-enzymatic antioxidants (ascorbic acid, total antioxidant capacity, phenolics and flavonoids). Bioaccumulation factor (BF) and translocation factor (TF) indicated that Cd and Pb accumulated largely in the roots, with little transfer to the shoots. Nevertheless, compared with heavy metal treatments, S. platensis at 0.1% significantly increasing growth parameters, oil content, photosynthetic pigments, and the activity of non-enzymatic and enzymatic antioxidants, while, slightly reduced TF of Cd and Pb, alleviated membrane lipid peroxidation, and significantly lowered the content of malondialdehyde, hydrogen peroxide, and indole acetic acid oxidase (IAAO) activity in heavy metal (Cd, Pb, and Cd + Pb)-treated rosemary plants.

Mini-Review: brown macroalgae as a promising raw material to produce biostimulants for the agriculture sector

The worldwide growing food demand and the excessive use of synthetic and chemical inputs compel the agricultural sector to find innovative and sustainable solutions to enhance or at least maintain crop yields in times of increased abiotic stresses levels linked to global change. Currently, great research efforts are carried out on brown seaweeds as their environment lead them to produce a broad range of compounds, with osmoregulatory, antioxidant, pro-bacterial, and plant-growth promoting activities. Indeed, numerous studies are looking at different combinations of algal species, extraction processes, plant species and environments of plant culture to highlight the various effects of algal extracts on plant growth and development, and resistance to abiotic stresses. Consequently, a wide variety of novel commercial products are emerging, presenting diversified chemical compositions, formulations and means of application. Such products allow the biostimulation of plants and soil by alleviating abiotic stresses such as drought, frost, and salt. The action of brown macroalgal extracts on plant and soil health has been repeatedly demonstrated, yet the precise relation between the extract chemical composition and its subsequent effect is still to be elucidated, as molecular synergy is suspected to play an important role. In this review, we present the interest of using brown macroalgal extracts to produce biostimulants with beneficial action on soil health, plant growth and development, as well as resistance against abiotic stresses, in relation to the molecular changes occurring.

Sargassum natans I Algae: An Alternative for a Greener Approach for the Synthesis of ZnO Nanostructures with Biological and Environmental Applications.

In this work, the influence of the Sargassum natans I alga extract on the morphological characteristics of synthesized ZnO nanostructures, with potential biological and environmental applications, was evaluated. For this purpose, different ZnO geometries were synthesized by the co-precipitation method, using Sargassum natans I alga extract as stabilizing agent. Four extract volumes (5, 10, 20, and 50 mL) were evaluated to obtain the different nanostructures. Moreover, a sample by chemical synthesis, without the addition of extract, was prepared. The characterization of the ZnO samples was carried out by UV-Vis spectroscopy, FT-IR spectroscopy, X-ray diffraction, and scanning electron microscopy. The results showed that the Sargassum alga extract has a fundamental role in the stabilization process of the ZnO nanoparticles. In addition, it was shown that the increase in the Sargassum alga extract leads to preferential growth and arrangement, obtaining well-defined shaped particles. ZnO nanostructures demonstrated significant anti-inflammatory response by the in vitro egg albumin protein denaturation for biological purposes. Additionally, quantitative antibacterial analysis (AA) showed that the ZnO nanostructures synthesized with 10 and 20 mL of extract demonstrated high AA against Gram (+) S. aureus and moderate AA behavior against Gram (-) P. aeruginosa, depending on the ZnO arrangement induced by the Sargassum natans I alga extract and the nanoparticles' concentration (ca. 3200 µg/mL). Additionally, ZnO samples were evaluated as photocatalytic materials through the degradation of organic dyes. Complete degradation of both methyl violet and malachite green were achieved using the ZnO sample synthesized with 50 mL of extract. In all cases, the well-defined morphology of ZnO induced by the Sargassum natans I alga extract played a key role in the combined biological/environmental performance.

Bioprospection of the trichomonacidal activity of lipid extracts derived from marine macroalgae Gigartina skottsbergii.

Algal extracts are sources of bioactive substances with applications in the development of novel alternative drugs against several diseases, including trichomoniasis sexually transmitted infection caused by Trichomonas vaginalis. Factors such as clinical failures and resistant strains limit the success of the existing drugs available for treating this disease. Therefore, searching for viable alternatives to these drugs is essential for the treatment of this disease. The present study was conducted for, in vitro and in silico characterization of extracts obtained from marine macroalgae Gigartina skottsbergii at stages gametophidic, cystocarpic, and tetrasporophidic. In addition, antiparasitic activity of these extracts against the ATCC 30236 isolate of T. vaginalis, their cytotoxicity, and gene expression of trophozoites after treatment were evaluated. The minimum inhibitory concentration and 50% inhibition concentration were determined for each extract. Results: In vitro analysis of the extracts' anti-T. vaginalis activity revealed an inhibitory effect of 100%, 89.61%, and 86.95% for Gigartina skottsbergii at stages gametophidic, cystocarpic, and tetrasporophidic, respectively, at 100 μg/mL. In silico analysis revealed the interactions between constituents of the extracts and enzymes from T. vaginalis, with significant free energy values obtained for the binding. None of the extract concentrations exhibited cytotoxic effects on VERO cell line compared to control, while cytotoxicity on HMVII vaginal epithelial cells line was observed at 100 μg/mL (30% inhibition). Gene expression analysis revealed differences in the expression profile of T. vaginalis enzymes between the extract-treated and control groups. According to these results, Gigartina skottsbergii extracts exhibited satisfactory antiparasitic activity.

Oil-Biodegradation Potential of Bacterial Communities by using Algae Extract as Bio-Stimulant

Oil-Biodegradation Potential of Bacterial Communities by using Algae Extract as Bio-Stimulant

Seaweed extracts as biological control of aflatoxins produced by Aspergillus parasiticus and Aspergillus flavus

BackgroundMycotoxins are secondary metabolites made by a variety of molds and fungi. They contaminate a lot of food products and local crops during pre- and post-harvesting under favorable conditions like high temperature and moisture. Aspergillus species are the most common fungi that contaminate food and produce biochemicals known as mycotoxins. Aflatoxins (AFB1, AFB2, AFG1, and AFG2) are the major mycotoxins produced by A. flavus and A. parasiticus that harm animal and human health. These fungi are controlled by chemical fungicides, but these are harmful to the environment. The aim of this study was to determine whether the aflatoxigenic fungi can be exterminated only by marine algal extracts or not.ResultsThe findings showed that the tested seaweed extracts inhibited fungal growth and aflatoxins production to varying degrees. The maximum antifungal activity was recorded in Halimeda opuntia extract against A. parasiticus-24 and A. flavus-18 and Turbunaria decurrens extract against A. flavus-18 (with an inhibition percentage of 77.78%), followed by Jania rubens extract against A. parasiticus-16 with inhibition percentage 75.88% compared to the control. Aqueous extract of H. opuntia effectively eliminated aflatoxins (B1, B2, G1, and G2) in A. parasiticus-16 and A. parasiticus-24. T. decurrens extract could detoxify 100% of aflatoxins in three isolates of A. parasiticus. J. rubens extract eliminated aflatoxins in A. parasiticus-15 and A. parasiticus-16 compared to their normal production using high-performance liquid chromatography.ConclusionsAccording to this study, the macroalgal species with numerous distinctive antifungal properties constituents significantly inhibited the growth and production of aflatoxin in A. parasiticus and A. flavus isolates. The findings supported the use of macroalgae as a biological control agent against fungi and their toxins.

Microbe-assisted seedling crop improvement by a seaweed extract to address fucalean forest restoration

In the Mediterranean, Cystoseira sensu lato (s.l.) (Phaeophyceae) forests have sharply declined and restoration measures are needed to compensate for the loss. Assisted regeneration through the outplanting of seedlings grown ex-situ has proven to be a sustainable option. Optimizing mesocosm culture can maximize survival of the most critical embryonic stages and reduce long-term maintenance costs. Host-microbiome interactions could also play a crucial role in seedling development and welfare. In this context, we aimed to advance a cultivation protocol that stimulates the growth and fitness of Ericaria amentacea (Phaeophyceae) seedlings and identify the associated microbial biofilm communities. Seedlings were cultured in 6 treatments [i.e., filtered seawater (SW, C, Control), von Stoch-enriched SW (VS), VS + algal extract (VSA), algal extract-enriched SW: A1< A2< A3]. After the field, A2 seedlings had the highest cover (1372 ± 53.66 mm2), which was 1.8 and 1.9 times greater than in VS and VSA, respectively. The addition of the algal extract and nutrients significantly affected the structure and composition of the microbial community that shifted over time in each culture medium. We identified a treatment-specific microbial fingerprint. After the mesocosm phase, A2 was characterized by 4 unique taxa: Postechiella, Winogradskyella, Roseovarius and Arenibacter (Bacteria). Given the success of A2 seedlings, we propose the probiotic consortia candidates characterized by the unique treatment-taxa in conjunction with the shared taxon Psychroserpens (Bacteria, present in A1, A2, VSA, VS) and the reminder community. Within the holobiont concept, the effect of algal extract or nutrients on the algae and/or biofilm could have important consequences for tuning the overall interaction networks. Our study has shown that macroalgal restoration could benefit from both the use of commercial algal extract and tailored nutrient enrichment in ex-situ cultures and the identification of probiotic consortia candidates that promote seedling growth.

Fungal Growth Inhibition of Bipolaris sorokiniana Causal Agent of Wheat Diseases and Activating Defense Systems of Plants Using Algae Extracts

Fungal Growth Inhibition of Bipolaris sorokiniana Causal Agent of Wheat Diseases and Activating Defense Systems of Plants Using Algae Extracts

Leukocyte Differentiation Mice (Mus Musculus) Infected with Plasmodium Berghei after Therapy With Sargassum Duplicatum Extract

Leukocytes are white blood cells produced by hematopoietic tissue that serves to help the body fight various infectious diseases as part of the immune system. Sargassum duplicatum contains steroid, alkaloid, phenol, flavonoid, saponin, and tannin compounds that can be immunomodulatory. The purpose of this research is to know the effect of methane extract of brown algae Sargassum duplicatum on the differentiation of leukocyte mice (Mus musculus) infected with Plasmodium berghei. Mice weighing 20-30 grams in Plasmodium berghei infection as much as 0.1 ml per head and left to the percentage of parasitemia reaches 1-5%. Then the mice (Mus musculus) were given brown algae methanol extract (Sargassum duplicatum) at doses 10, 100, and 200 mg / g BW for 4 consecutive days. From day 0 to 6 also made a blood smear to calculate the number of leukocytes. Data analysis will be done using ANOVA. The results showed that the administration of brown algae extracts of Sargassum duplicatum influenced in increasing the number of neutrophils, monocytes, and basophils and decreased the number of eosinophils and lymphocytes of mice infected with Plasmodium berghei to near normal range. Dose 200 mg/kg BB methanol extract of brown alga Sargassum duplicatum is a dose that can affect the number of neutrophils, eosinophils, lymphocytes, and monocytes of mice infected with Plasmodium berghei most closely to normal range.

Assessment of anticancer, antibacterial, antifungal, and antioxidant activities of Micractinium reisseri (Chlorophyta, Trebouxiophyceae) methanolic extract

This study looked at the anticancer, antimicrobial, and antioxidant properties of a methanolic extract of Micractinium reisseri. In vitro antitumor activity of M. reisseri methanolic extract revealed an inhibitory effect against MCF-7 and HCT-116 (breast carcinoma and colon carcinoma) cell lines. Antimicrobial activity of M. reisseri methanolic extract was estimated against Gram-negative bacteria (Pseudomonas aeruginosa RCMB 010,049 and Escherichia coli RCMB 010,052), Gram-positive bacteria (Streptococcus pneumonia RCMB 010,010 and Bacillus subtilis RCMB 010,067) and fungi (Aspergillus fumigatus RCMB 02,568 and Candida albicans RCMB 05,036). The extract showed promising results against all the tested microbes except C. albicans which gave negative results. The algal extract showed 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing and hydroxyl radical scavenging activity in a concentration-dependent manner with maximum scavenging activity at concentrations (0.001, 0.001, and 5 mg/ml) for each assay, respectively. High-performance liquid chromatography (HPLC) revealed that the active compounds are phenols, alkaloids, and flavonoids. In conclusion, M. reisseri methanolic extract exhibited effective anticancer, antimicrobial, and antioxidant activities.

Antiviral activity of red algae phycocolloids against herpes simplex virus type 2 in vitro

Herpes simplex virus type 2 (HSV-2) is a human infectious agent with significant impact on public health due to its high prevalence in the population and its ability to elicit a wide range of diseases, from mild to severe. Although several antiviral drugs, such as acyclovir, are currently available to treat HSV-2-related clinical manifestations, their effectiveness is poor. Therefore, the identification and development of new antiviral drugs against HSV-2 is necessary. Seaweeds are attractive candidates for such purposes because they are a vast source of natural products due to their highly diverse compounds, many with demonstrated biological activity. In this study, we evaluated the in vitro antiviral potential of red algae extracts obtained from Agarophyton chilense, Mazzaella laminarioides, Porphyridium cruentum, and Porphyridium purpureum against HSV-2. The phycocolloids agar and carrageenan obtained from the macroalgae dry biomass of A. chilense and M. laminarioides and the exopolysaccharides from P. cruentum and P. purpureum were evaluated. The cytotoxicity of these extracts and the surpluses obtained in the extraction process of the agar and carrageenans were evaluated in human epithelial cells (HeLa cells) in addition to their antiviral activity against HSV-2, which were used to calculate selectivity indexes (SIs). Several compounds displayed antiviral activity against HSV-2, but carrageenans were not considered as a potential antiviral therapeutic agent when compared to the other algae extracts with a SI of 23.3. Future assays in vivo models for HSV-2 infection should reveal the therapeutic potential of these algae compounds as new antivirals against this virus.

Antimicrobial and anti-biofilm activity of silver nanoparticles biosynthesized with Cystoseira algae extracts

Antimicrobial resistance is an ever-growing global concern to public health with no clear or immediate solution. Silver nanoparticles (AgNPs) have long been proposed as efficient agents to fight the growing number of antibiotic-resistant strains. However, the synthesis of these particles is often linked to high costs and the use of toxic, hazardous chemicals, with environmental and health impact. In this study, we successfully produced AgNPs by green synthesis with the aid of the extract of two brown algae—Cystoseira baccata (CB) and Cystoseira tamariscifolia (CT)—and characterized their physico-chemical properties. The NPs produced in both cases (Ag@CB and Ag@CT) present similar sizes, with mean diameters of around 22 nm. The antioxidant activity of the extracts and the NPs was evaluated, with the extracts showing important antioxidant activity. The bacteriostatic and bactericidal properties of both Ag@CB and Ag@CT were tested and compared with gold NPs produced in the same algae extracts as previously reported. AgNPs demonstrated the strongest bacteriostatic and bactericidal properties, at concentrations as low as 2.16 µg/mL against Pseudomonas aeruginosa and Escherichia coli. Finally, the capacity of these samples to prevent the formation of biofilms characteristic of infections with a poorer outcome was assessed, obtaining similar results. This work points towards an alternative for the treatment of bacterial infections, even biofilm-inducing, with the possibility of minimizing the risk of drug resistance, albeit the necessary caution implied using metallic NPs.Graphical abstract

Roles of Marine Macroalgae or Seaweeds and Their Bioactive Compounds in Combating Overweight, Obesity and Diabetes: A Comprehensive Review

Obesity and diabetes are matters of serious concern in the health sector due to their rapid increase in prevalence over the last three decades. Obesity is a severe metabolic problem that results in energy imbalance that is persistent over a long period of time, and it is characterized by insulin resistance, suggesting a strong association with type 2 diabetes (T2D). The available therapies for these diseases have side effects and some still need to be approved by the Food and Drug Administration (FDA), and they are expensive for underdeveloped countries. Hence, the need for natural anti-obesity and anti-diabetic drugs has increased in recent years due to their lower costs and having virtually no or negligible side effects. This review thoroughly examined the anti-obesity and anti-diabetic effects of various marine macroalgae or seaweeds and their bioactive compounds in different experimental settings. According to the findings of this review, seaweeds and their bioactive compounds have been shown to have strong potential to alleviate obesity and diabetes in both in vitro and in vivo or animal-model studies. However, the number of clinical trials in this regard is limited. Hence, further studies investigating the effects of marine algal extracts and their bioactive compounds in clinical settings are required for developing anti-obesity and anti-diabetic medicines with better efficacy but lower or no side effects.

Anti-Steatotic Effects of Chlorella vulgaris, Nannochloropsis gaditana and Gracilaria vermiculophylla Algae Extracts in AML-12 Hepatocytes.

Non-alcoholic fatty liver disease (NAFLD) is considered the most common chronic liver alteration whose prevalence is increasing in Western countries. Microalgae and macroalgae have attracted great interest due to the high content in bioactive compounds with beneficial effects on health. The aim of the present study is to assess the potential interest of extracts rich in proteins obtained from the microalgae Chlorella vulgaris and Nannochloropsis gaditana and the macroalga Gracilaria vermiculophylla in the prevention of lipid accumulation in AML-12 hepatocytes. Toxicity was not observed at any of the tested doses. Both microalgae and the macroalga were effective in preventing triglyceride accumulation, with Nannochloropsis gaditana being the most effective one. Although the three algae extracts were able to increase different catabolic pathways involved in triglyceride metabolism, the mechanisms underlying the anti-steatotic effect were different in each algae extract. In conclusion, the present study demonstrates that Chlorella vulgaris, Nannochloropsis gaditana and Gracilaria vermiculophylla extracts are able to partially prevent the accumulation of triglycerides induced by palmitic acid in cultured hepatocytes, a model used to mimic the steatosis induced in liver by dietary patterns rich in saturated fat.

In Vitro and In Vivo Antidiabetic, α-Glucosidase Inhibition and Antibacterial Activities of Three Brown Algae, Polycladia myrica, Padina antillarum, and Sargassum boveanum, and a Red Alga, Palisada perforata from the Persian Gulf.

In recent decades, algae have attracted worldwide attention for their great biological activities, such as antidiabetic and antibacterial properties. We measured antibacterial and α-glucosidase inhibition potential of methanol and 80% methanol extracts of three brown algae species, Polycladia myrica, Padina antillarum, and Sargassum boveanum, and a red alga, Palisada perforata, from the Persian Gulf coasts. Antibacterial activity of the algal extracts was assessed by broth dilution method against three gram-negative and -positive bacteria, including Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa; Staphylococcus epidermidis, Staphylococcus aureus, and Bacillus subtilis, respectively. Furthermore, the yeast's α-glucosidase inhibition of the algal extracts was measured via colorimetric assay. In addition, we investigated the beneficial effect of 80% MeOH extract of S. boveanum on the blood glucose levels in streptozotocin-induced diabetic rats. The MeOH extract of S. boveanum was the best antibacterial extract with MIC = 2.5 mg/mL against all bacterial strains except for E. coli. The MeOH and 80% MeOH extracts of P. myrica and P. antillarum inhibited α-glucosidase at most with IC50 values of 12.70 ± 1.88 µg/mL and 13.06 ± 4.44 µg/mL, respectively. The oral gavage of S. boveanum extract in streptozotocin- (STZ-) induced diabetic rats resulted in decreasing their postprandial blood glucose levels. The algae and acarbose decreased blood glucose levels after sucrose administration in 60 minutes, compared to the non-drug-treated animals, with p values of 0.03 and 0.007, respectively. Overall, due to the in vitro and in vivo antidiabetic potential of S. boveanum, we suggest the alga as a new source for the isolation and identification of potential antidiabetic and antibacterial compounds.

Suppression of hepatocellular carcinoma by Ulva lactuca ulvan via gut microbiota and metabolite interactions

IntroductionUlva lactuca polysaccharide (ULP) is green algae extract with numerous biological activities, including anticoagulant, anti-inflammatory, and antiviral effects. However, the inhibitory ability of ULP in the development of hepatocellular carcinoma warrants further studies. ObjectivesTo elucidate the anti-tumor mechanism of ULP action and evaluate its regulatory effect on gut microbiota and metabolism in H22 hepatocellular carcinoma tumor-bearing mice. MethodsAn H22 tumor-bearing mouse model was established by subcutaneously injecting H22 hepatoma cells. The gut microbiota composition in cecal feces was assessed and subjected to untargeted metabolomic sequencing. The antitumor activity of ULP was verified further by western blot, RT-qPCR, and reactive oxygen species (ROS) assays. ResultsAdministration of ULP alleviated tumor growth by modulating the compositions of the gut microbial communities (Tenericutes, Agathobacter, Ruminiclostridium, Parabacteroides, Lactobacillus, and Holdemania) and metabolites (docosahexaenoic acid, uric acid, N-Oleoyl Dopamine, and L-Kynurenine). Mechanistically, ULP promoted ROS production by inhibiting the protein levels of JNK, c-JUN, PI3K, Akt, and Bcl-6, thereby delaying the growth of HepG2 cells. ConclusionULP attenuates tumor growth in H22 tumor-bearing mice by modulating gut microbial composition and metabolism. ULP inhibits tumor growth mainly by promoting ROS generation.

Green biosynthesis, characterization of silver nanoparticles using a green alga Spirogyra sp., and their antioxidant and enzyme activities

A simple, environmentally friendly, inexpensive, and one-step alternative method was reported for the green biosynthesis of silver nanoparticles (AgNPs) operating the Spirogyra sp. extract as a reducing and stabilizing substance. Concentration of AgNO3 and reaction time were optimized to prepare AgNPs under controlled conditions. The synthesized silver nanoparticles were characterized by UV-Vis absorption spectroscopy, fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), and elemental mapping. The TEM analysis showed that the average particle size of AgNPs was 18.3 nm. Structural details of silver nanoparticles elucidated by Selected Area Electron Diffraction (SAED) based on TEM images. In addition, biological activity tests were applied to nanoparticles and algal extracts to determine antioxidant activity (3 different tests: DPPH (1,1-diphenyl-2-picrylhydrazil) radical scavenging activity, total phenolic content (TPC) and total flavonoid content (TFC)) and α-glucosidase enzyme inhibition. Antioxidant activity and α-glucosidase enzyme inhibition values of silver nanoparticles are higher than the values of Spirogyra sp. extracts.

Effect of Algae Chlorella extracts for treatment of intestinal tissues of mice infected with Cryptosporidium spp.

Cryptosporidium is a protozoan parasite of medical importance that causes gastroenteritis in a variety of vertebrate hosts, so the study was conducted to evaluate the anti-cryptosporidiosis efficacy of alcoholic and aqueous Chlorella algae extracts in comparison with Azithromycin in the intestines of infected mice. Fecal samples were collected from patients at Al-Kut Hospital suffering from diarrhea in the period December 2021 to end of March 2022, and 90 microscopic samples of both sexes were examined using a modified Ziell-Nelson stain to detect oocysts infected with the parasite. Isolation and flotation purification with Sheather's sugar solution and preservation in potassium dichromate for the purpose of infection in mice. The Experimental study was on groups of 57 mice by dealing with oral parasite oral oocysts within 104 oocyst/ ml except for the negative group addressed by a fishery saline solution. To strict injury, the detailed mice has been examined with microscopic parasites using Ziehl-Nelson Stain, and molecular screening was performed using Multiplex PCR technology. After the mice were divided into five groups with the uninfected and untreated group kept as a healthy negative control. The first group which included 21 mice was treated after it was divided into three subgroups A, B, C for each secondary group 7 mice they were treated with alcoholic extract of Chlorella at different concentrations 50, 100, 150 mg/ml on the respectively, while the second group which included 21 mice on three groups A, B, and C was treated with aqueous extract of Chlorella at the previous concentrations for three consecutive days for each concentration. The third group was treated with azithromycin at a concentration of 500 ml, and the positive control group remained infected with the parasite and was not treated. After treatment a microscopic examination was performed by evaluating the excretion average of parasite oocysts using a hematocytometer slide. The results of histological examination showed that treatment with alcoholic and aqueous Chlorella algae extracts led to remarkable repair and regeneration with restructuring in all sections of the small intestine infected with Cryptosporidium spp. parasite to varying degrees according to the concentrations used. Whereas the groups treated with Chlorella algae extracts showed epithelial layers renewed with the formation of non-enlarged cells and less edema, in addition less infiltration of inflammatory cells was observed in the submucosal layer. There was a slight inflammation in the tissues of the duodenum, jejunum, and ileum with a clear decrease in inflation and the degree of inflammation as well as less severe lesions in the intestinal tissues treated with alcoholic and aqueous extract of Chlorella algae in the highest concentrations with complete disappearance of parasite oocysts.Key words: Intestine, Cryptosporidium spp., Chlorella