Alternative green solvents associated with ultrasound-assisted extraction: A green chemistry approach for the extraction of carotenoids and chlorophylls from microalgae.

This study proposes a method for the ultrasonic extraction of carotenoids and chlorophyll from Scenedesmus obliquus and Arthrospira platensis microalgae with green solvents. Ethanol and ethanolic solutions of ionic liquids were tested with a variety of extraction parameters, including number of extractions, time of extraction, and solid-liquid ratio R(S/L), to determine the optimal conditions. After selecting the most effective green solvent (ethanol), the process conditions were established: R(S/L) of 1:10, three extraction cycles at 3 min each), giving an extraction yield of 2602.36 and 764.21 µgcarotenoids.gdried biomass-1; and 22.01 and 5.81 mgchlorophyll.gdried biomass-1 in S. obliquus and A. platensis, respectively. The carotenoid and chlorophyll extracts obtained using ethanol were shown to be potent scavengers of peroxyl radical, being 5.94 to 26.08 times more potent α-tocopherol. These findings pave the way for a green strategy for valorizing microalgal biocompounds through efficient and environmentally friendly technological processes.

Effect of Inclusion of Arthrospira maxima Microalgae in Laying Hen Diets on Production Parameters and Egg Characteristics

The animal feed industry is continuously researching new feed additives to substitute other materials, reduce costs, or add value to the final product. The microalgae Arthrospira maxima, cultivated using wastewater as a nutritional source, was evaluated as a feed additive by including 2, 4, and 6% in isocaloric and isoprotein diets for laying hens. Five replicates per treatment with 5 hens per cage were used during an experimental period of 28 days. Productive behavior and egg characteristics (quality, fatty acid profile, cholesterol level) were evaluated. The inclusion of microalgae up to 4% in diets for 52-week-old laying hens did not affect productive performance (egg production, egg weight, egg mass, FCR, shell thickness, and Haugh units). No effects were observed on the cholesterol level or the concentration of fatty acids in the eggs, but more information is needed to determine if the microalgae drying or storage process can generate variations of these results. The inclusion of 6% microalgae produced an acceptable egg yolk color for the local market. The results indicate that this material can be used as a protein source up to an inclusion of 4% in the diet, and hens may need an adaptation period to maintain production at the 6% inclusion level.(AU)

Effect of adding Spirulina platensis algae to small ruminant rations on productive, reproductive traits and some blood components

This experiment conducted using 20 Rahmani ewes at the last third of pregnancy in two equal groups. One group served as control, while the other group received Spirulina platensis(SP) at the rate of 0.5 gm 10 kg-1live body weight. The objective was to find out the effect of adding Spirulina platensisalgae to small ruminant rations on reproductive and productive traits and blood components of sheep. The experiments lasted for 120 days for both dams and their lambs after weaning. The findings proved that adding SP in ewes' diets had no effect on the average of live body weight change. Average milk yield was significantly (p <0.01) higher in the treatment group than the control. Lamb's birth weight and daily body gain of the treated group were significantly (p <0.01) higher than the control. Blood and serum picture profile of ewes were significantly higher when fed SP additive than the control.It could be concluded that the addition of SP to the ration of sheep positively preserved their health, productive and reproductive status as well as their lambs' growth rate. Also the additive improved the economic efficiency of treated animals by about 53.13%.(AU)

Bioactive Compounds of Arthrospira spp. (Spirulina) with Potential Anticancer Activities: A Systematic Review.

Arthrospira, a genus of blue-green cyanobacteria, is known for its great biological activity due to the presence of a large number of substances that are potentially active against tumor cells. This review aimed to evaluate the potential of Arthrospira spp. for the treatment or reduction of several types of cancer, in addition to elucidating the mechanism of action by which their compounds act on tumor cells. A systematic review was carried out in PubMed, Science Direct, LILACS, and SciELO databases, including original studies from 2009 to 2020. A total of 1306 articles were independently assessed according to the eligibility criteria, of which 20 articles were selected and assessed for the risk of bias using seven criteria developed by the authors. Arthrospira spp. of cyanobacteria have been evaluated against eight different types of cancer, mainly colon cancer. Among all the compounds, phycocyanin was the most used, followed by peptides and photosensitizers. In general, compounds from Arthrospira spp. act as anticancer agents by inhibiting the proliferation of tumor cells, triggering cell cycle arrest, and inducing apoptosis via different signaling pathways. In addition, these compounds also exhibited antioxidant, antiangiogenic, and antimetastatic activities. Phycocyanin demonstrated better efficacy against several types of cancer via different activities and therapeutic targets. Furthermore, it was the only molecule that functioned in synergy with other drugs that are already well established for the treatment of cancer.

Spirulina platensis Consumption Prevents Obesity and Improves the Deleterious Effects on Intestinal Reactivity in Rats Fed a Hypercaloric Diet.

The consumption of hypercaloric diets is related to the development of obesity, favoring the etiology of gastrointestinal disorders. In this context, Spirulina platensis (SP), some blue-green algae with antioxidant action, appears as a potential therapeutic alternative to prevent obesity and associated intestinal disorders. Thus, the present study is aimed at evaluating the deleterious effects of the hypercaloric diet on the contractile and relaxing reactivity of the ileum of rats, as well as the possible preventive mechanisms of dietary supplementation with SP. Wistar rats were divided into three groups: fed a standard diet (SD), a hypercaloric diet (HCD), and/or supplemented with 25 mg/kg SP (HCD + SP25) for 8 weeks. The hypercaloric diet was effective in promoting obesity in rats, as well as decreasing potency and ileal relaxing and contractile efficacy. In contrast, dietary supplementation with SP was able to prevent some of the parameters of experimental obesity. In addition, SP prevented the reduction of intestinal reactivity, possibly due to a positive modulation of voltage-gated calcium channels (CaV) and negative regulation of muscarinic receptors (M3). Thus, food supplementation with Spirulina platensis becomes a promising alternative in the prevention of gastrointestinal diseases induced and/or aggravated by obesity.

Involvement of Opioid System and TRPM8/TRPA1 Channels in the Antinociceptive Effect of Spirulina platensis.

Spirulina platensis is a "super-food" and has attracted researchers' attention due to its anti-inflammatory, antioxidant, and analgesic properties. Herein, we investigated the antinociceptive effects of Spirulina in different rodent behavior models of inflammatory pain. Male Swiss mice were treated with Spirulina (3-300 mg/kg, p.o.), indomethacin (10 mg/kg, p.o.), or vehicle (0.9% NaCl 10 mL/kg). Behavioral tests were performed with administration of acetic acid (0.6%, i.p.), formalin 2.7% (formaldehyde 1%, i.pl.), menthol (1.2 µmol/paw, i.pl.), cinnamaldehyde (10 nmol/paw, i.pl.), capsaicin (1.6 µg/paw, i.pl.), glutamate (20 µmol/paw, i.pl.), or naloxone (1 mg/kg, i.p.). The animals were also exposed to the rotarod and open field test to determine possible effects of Spirulina on locomotion and motor coordination. The quantitative phytochemical assays exhibited that Spirulina contains significant concentrations of total phenols and flavonoid contents, as well as it showed a powerful antioxidant effect with the highest scavenging activity. Oral administration of Spirulina completely inhibited the abdominal contortions induced by acetic acid (ED50 = 20.51 mg/kg). Spirulina treatment showed significant inhibition of formalin-induced nociceptive behavior during the inflammatory phase, and the opioid-selective antagonist markedly blocked this effect. Furthermore, our data indicate that the mechanisms underlying Spirulina analgesia appear to be related to its ability to modulate TRMP8 and TRPA1, but not by TRPV1 or glutamatergic system. Spirulina represents an orally active and safe natural analgesic that exhibits great therapeutic potential for managing inflammatory pain disorders.

Spirulina sp. LEB 18-extracted phycocyanin: Effects on liposomes' physicochemical parameters and correlation with antiradical/antioxidant properties.

This study describes the physicochemical properties of soybean asolectin (ASO) liposomes loaded with phycocyanin (Phy) extracted from Spirulina sp. LEB 18. The effects of Phy in the liposomes' properties were investigated by Fourier transform infrared spectroscopy (FTIR), 1H and 31P nuclear magnetic resonance (NMR), zeta (ζ)-potential, dynamic light scattering (DLS) and ultraviolet-visible (UV-vis) techniques. Phy restricted the motion of ASO polar and interface groups and disrupted the package arrangement of the lipid hydrophobic regions, as a likely effect of dipolar and π interactions related to its amino acid residues and pyrrole portions. These interactions were correlated to antiradical/antioxidant Phy responses obtained by 2,2-diphenyl-1-picrylhidrazil (DPPH) assay, thiobarbituric acid reactive substances (TBARS) and ferric reducing antioxidant power (FRAP) methods, and discussed to bring new chemical perspectives about Phy-loaded liposomes-related nutraceutical applications in inflammatory and viral infection processes.

Spirulina ameliorates arsenic induced reproductive toxicity in male rats

Spirulina (Spirulina platensis), has numerous health benefits including antioxidant, immunomodulatory, and anti-inflammatory activities, works against heavy metal toxicity, and is often used as a food supplement in human, animals, birds and fishes. This study aimed to evaluate the protective ability of the dietary spirulina against the toxic effects of inorganic arsenic (iAs) on male reproductive parameters in rats. Seventy-two mature Long-Evans male rats, dividing into six groups (T0, T1, T2, T3, T4 and T5) (12 rats/group) were included in this study. The T3, T4 and T5 group rats were treated with three consecutive doses (1.0 g, 1.5 g and 2.0 g/kg feed) of spirulina in feed along with 3.0 mg NaAsO2/kg body weight (BW) in drinking water (DW) daily for 90 days. Each rat of group T1 received NaAsO2 (3.0 mg/kg BW) in DW, and those of T2 group were fed with spirulina (2.0 g/kg feed) daily for 90 days. The rats of group T0 served as the control with normal feed and water. Total arsenic (tAs) contents, reproductive parameters (testicular weight, sperm motility and morphology), and histological changes in the testicles were evaluated in these rats. Arsenic dosing significantly (p=0.003, Kruskal-Wallis test) increased the tAs contents in the testicles, decreased testes weight, sperm morphology and motility compared to the controls. The effect of arsenic dosing was also evidenced by the histological changes like decreased germinal layers in the seminiferous tubules of the treated rats. Moreover, dietary spirulina (2.0 g/kg feed) supplementation significantly (p=0.011, Kruskal-Wallis test) lowered tAs contents in testicles and increases testes weights, sperm motility and morphology. Therefore, spirulina can be used as an effective dietary supplement to ameliorate the adverse effects of arsenic induced reproductive toxicities. However, further study is required to elucidate the underlying molecular mechanisms of reduction of arsenic induced reproductive toxicity by spirulina.(AU)

Beyond Fish Oil Supplementation: The Effects of Alternative Plant Sources of Omega-3 Polyunsaturated Fatty Acids upon Lipid Indexes and Cardiometabolic Biomarkers-An Overview.

Cardiovascular diseases remain a global challenge, and lipid-associated biomarkers can predict cardiovascular events. Extensive research on cardiovascular benefits of omega-3 polyunsaturated fatty acids (n3-PUFAs) is geared towards fish oil supplementation and fish-rich diets. Nevertheless, vegetarianism and veganism are becoming more popular across all segments of society, due to reasons as varied as personal, ethical and religious values, individual preferences and environment-related principles, amongst others. Due to the essentiality of PUFAs, plant sources of n3-PUFAs warrant further consideration. In this review, we have critically appraised the efficacy of plant-derived n3-PUFAs from foodstuffs and supplements upon lipid profile and selected cardiometabolic markers. Walnuts and flaxseed are the most common plant sources of n3-PUFAs, mainly alpha-linolenic acid (ALA), and feature the strongest scientific rationale for applicability into clinical practice. Furthermore, walnuts and flaxseed are sources of fibre, potassium, magnesium, and non-essential substances, including polyphenols and sterols, which in conjunction are known to ameliorate cardiovascular metabolism. ALA levels in rapeseed and soybean oils are only slight when compared to flaxseed oil. Spirulina and Chlorella, biomasses of cyanobacteria and green algae, are important sources of n3-PUFAs; however, their benefits upon cardiometabolic markers are plausibly driven by their antioxidant potential combined with their n3-PUFA content. In humans, ALA is not sufficiently bioconverted into eicosapentaenoic and docosahexaenoic acids. However, evidence suggests that plant sources of ALA are associated with favourable cardiometabolic status. ALA supplementation, or increased consumption of ALA-rich foodstuffs, combined with reduced omega-6 (n6) PUFAs intake, could improve the n3/n6 ratio and improve cardiometabolic and lipid profile.

The Effect of Gelatine Packaging Film Containing a Spirulina platensis Protein Concentrate on Atlantic Mackerel Shelf Life.

The use of packaging films containing natural preservative compounds attracts great attention for the quality improvement of seafood. Microalga spirulina (Spirulina platensis) represents a potential source of high added-value and preservative biocompounds. The goal of this study was to enhance the quality of refrigerated Atlantic mackerel (Scomber scombrus) by including a protein concentrate (PC) of spirulina in a gelatine-based film. Quality changes in fish muscle were monitored by microbial and chemical analyses throughout an 11-day refrigerated storage (4 °C). As a result of the presence of spirulina PC in the film, an antimicrobial effect (p < 0.05) was concluded as determined by comparative evolution of aerobes and psychrotrophs, while no effect (p > 0.05) was concluded for Enterobacteriaceae, proteolytics and lipolytics counts. Furthermore, a lower (p < 0.05) formation of trimethylamine and free fatty acids was detected. Lipid oxidation, measured by fluorescent compounds formation, also exhibited lower average values in fish corresponding to the batch containing spirulina concentrate. The preservative effects observed can be explained on the basis of the presence of antimicrobial and antioxidant compounds in the microalga concentrate. It is proposed that the current packaging system may constitute a novel and promising strategy to enhance the quality of commercial refrigerated fatty fish.

Potential Therapeutic Role of Dietary Supplementation with Spirulina platensis on the Erectile Function of Obese Rats Fed a Hypercaloric Diet.

Spirulina platensis, an important source of bioactive compounds, is a multicellular, filamentous cyanobacterium rich in high-quality proteins, vitamins, minerals, and antioxidants. Due to its nutrient composition, the alga is considered a complete food and is recognized for its anti-inflammatory, antioxidant, antiobesity, and reproprotective effects. All of which are important for prevention and treatment of organic and metabolic disorders such as obesity and erectile dysfunction. The aim of this study was to investigate the modulatory role of Spirulina platensis food supplementation and the mechanisms of action involved in reversing the damage caused by a hypercaloric diet on the erectile function of rats. The animals were divided into a standard diet group (SD, n = 5); a hypercaloric diet group (HCD, n = 5); a hypercaloric diet group supplemented with S. platensis at doses of 25 (HCD+SP25, n = 5), 50 (HCD+SP50, n = 5), and 100 mg/kg (HCD+SP100, n = 5); and a hypercaloric diet group subsequently fed a standard diet (HCD+SD, n = 5). In the rats fed a hypercaloric diet, dietary supplementation with S. platensis effectively increased the number of erections while decreasing latency to initiate penile erection. Additionally, S. platensis increases NO bioavailability, reduces inflammation by reducing the release of contractile prostanoids, enhances the relaxation effect promoted by acetylcholine (ACh), restores contractile reactivity damage and cavernous relaxation, reduces reactive oxygen species (ROS), and increases cavernous total antioxidant capacity (TAC). Food supplementation with S. platensis thus restores erectile function in obese rats, reduces production of contractile prostanoids, reduces oxidative stress, and increases NO bioavailability. Food supplementation with S. platensis thus emerges as a promising new therapeutic alternative for the treatment of erectile dysfunction as induced by obesity.

Development of chitosan/Spirulina sp. blend films as biosorbents for Cr6+ and Pb2+ removal.

Chitosan film, Spirulina sp. film and its blend were developed as biosorbents to remove Cr6+ and Pb2+ ions from aqueous solutions. The kinetic study and the pH effect on biosorption efficiency were evaluated to comprehend the interactions between the ions and biosorbents. The characterization analyses pointed out that occurred interaction between both biomaterials, which resulted in structural alterations through the blend. The Spirulina sp. film exhibited the highest biosorption capacities for Cr6+ (43.2 mg g-1) and Pb2+ (35.6 mg g-1) ions, however, its physical integrity was not kept in acid medium. The blend film showed results slightly lower (35.8 mg g-1 for Cr6+ and 31.6 mg g-1 for Pb2+), but its physical integrity remained intact in all assays. Chitosan film presented the lower biosorption capacities (15.4 mg g-1 for Cr6+ and 20.9 mg g-1 for Pb2+). Elovich and pseudo-second order models were the most suitable to express the kinetic behaviors for Cr6+ and Pb2+, respectively. Therefore, chitosan/Spirulina sp. blend could be a green alternative for Cr6+ and Pb2+ removal, because this biosorbent showed high biosorption capacity obtained from Spirulina sp. and great physical integrity obtained of chitosan.

The Antihypertensive, Antimicrobial and Anticancer Peptides from Arthrospira with Therapeutic Potential: A Mini Review.

The interest in biological peptides from Arthrospira sp. (syn Spirulina) is increasing due to its Generally Recognised as Safe "GRAS" status, the high concentration of proteins and the history of its use as a supplement and nutraceutical agent. Arthrospira peptides can be generated by the controlled hydrolysis of proteins, using proteases, followed by fractionation. The peptides obtained have a range of therapeutic effects. Amongst these bioactive peptides, three classes are of major importance: the antihypertensive (AHP), antimicrobial (AMP) and anticancer (ACP) peptides. AHPs have the ability to work as inhibitors of angiotensin-converting enzyme (ACE), and help to control several diseases such as hypertension, obesity, and cardiovascular issues, AMPs play a crucial role in the immune response, inhibiting the development of pathogens such as bacteria, fungi, viruses and others, while ACPs can aid in tumour control by the induction of apoptosis or necrosis, or the inhibition of angiogenesis. Thus, bioactive peptides are of great significance to the pharmaceutical industry. However, they can show secondary effects. This paper reviews the inhibition mechanism of antimicrobial, hypertensive and anticancer peptides from Arthrospira sp., and the possible structures of the peptides according to the type of activity and its intensity. In addition, this paper describes the purification methods of absorption mechanisms, and reviews databases for designing peptides.

Analysis of the use of a non-conventional rotary drum for dehydration of microalga Spirulina platensis.

The high content of bioactive compounds in the microalga Spirulina platensis has recently attracted attention from food and pharmaceutical industries. However, for its application an effective preservation technique must be developed. In this paper, we investigated the use of a non-conventional rotary dryer (with an inert bed) for drying the microalga Spirulina biomass and the effects of the operational conditions (air temperature, intermittent feeding interval, filling degree of inert particles, and rotation speed) on its bioactive compounds. The results indicated that this non-conventional drying system offers an effective alternative for expanding the use of this biomass in an adequate form. We identified the conditions in which the dried material had maintained satisfactory contents of phenolics (air temperature of 70 °C and intermittent feeding interval of 10 min), flavonoids (intermittent feeding interval of 17.4 min), and phycocyanin compounds (air temperature of 40 °C), which were near to those present in fresh microalga.

Polymethoxy-1-Alkenes Screening of Chlorella and Spirulina Food Supplements Coupled with In Vivo Toxicity Studies.

Selected species of cyanobacteria and green algae have been reported to produce lipophilic polymethoxy-1-alkenes (PMAs) which were shown to exhibit in vivo teratogenicity. Considering that information on PMAs in Arthospira sp. (known commercially as Spirulina) and Chlorella sp. cultivated for food supplement production was essentially lacking, the present study screened Chlorella (n = 10) and Spirulina (n = 13) food supplements registered in the European Union. Mass spectrometry analysis of column fractionated extracts was performed. None of the four variants previously reported in some cyanobacteria and green algae, nor any potentially related structures were detected in the studied samples. Since the isolated lipophilic fractions contained various compounds, they were further screened for in vivo teratogenicity in Danio rerio embryo, and for the potential to induce oxidative stress and genotoxicity in the liver and neurotoxicity in the brain of adult zebrafish. None of the tested food supplements had detectable levels of PMAs or any potentially related structures. No teratogenicity was revealed except for spinal curvature induced by fractions obtained from two Chlorella products. Selected fractions revealed cytotoxicity as indicated by an increased level of reactive oxygen species, catalase activity, lipid peroxidation and increased frequency of DNA strand breaks in hepatic tissue. The majority (60%) of Chlorella fractions induced an increase in cholinesterase activity in zebrafish brain homogenate while exposure to 61.5% of Spirulina fractions was associated with its decrease. The present study confirms that Chlorella and Spirulina food supplements are free of teratogenic PMAs, although the observed in vivo toxicities raise questions regarding the quality of selected products.

Development of functional pasta with microencapsulated Spirulina: technological and sensorial effects.

BACKGROUND: Spirulina microalgae have been added to food; however, there have been few reports on the methods used to protect the antioxidant potential against process conditions, and the effects on the sensory characteristics of products need to be better described. The aim of this study was to evaluate the influence on the technological properties, sensory profile, and acceptability of the pasta with free or microencapsulated Spirulina biomass added. Pasta formulations included: free Spirulina (FSP), microencapsulated Spirulina (MSP), and empty microspheres (EMP), which were compared with the control pasta (CP). RESULTS: The microencapsulation protected the antioxidant potential of Spirulina in 37.8% of the pasta cooking conditions. The microspheres presented low solubility in water (86 g.kg-1 ) and high encapsulation efficiency (87.6%), this being appropriate for addition to products that need cooking in water. The technological properties of pasta (water absorption, weight gain, firmness, and adhesiveness) were affected, but the overall acceptability index (85.13%) was not influenced by the addition of microspheres, despite changes observed in the sensory profile obtained by the CATA (check-all-that-apply). CONCLUSIONS: Spirulina could be added to pasta even without microencapsulation but the microencapsulation in alginate allows for the protection of the antioxidant potential of the biomass, representing a potential alternative for the bakery industry. © 2019 Society of Chemical Industry.

Arthrospira (Spirulina) Platensis Can Be Considered as a Probiotic Alternative to Reduce Heat Stress in Laying Japanese Quails

This study was conducted to investigate the effects of Arthrospira platensis (Spirulina platensis, SP) on feed intake, feed conversion ratio, egg weight, hen day egg production, intestinal microflora, heat stress biomarkers, and HSP70 gene expression in laying Japanese quails (Coturnix coturnix japonica) suffering heat stress condition. A total of 250 female quails were allocated to 5 treatments, 5 replicates and 10 birds in each replicate in a completely randomized design. Experimental treatments included: 1) basal diet, 2) basal diet+ 0.03 % probiotic, 3) basal diet+ 0.1 % SP, 4) basal diet+ 0.3 % SP, 5) basal diet+ 0.5 % SP. During the last 6 days of the experiment, the quails were exposed to 8h of 34±1°C. The birds had free access to feed and water during the experiment. The results showed that using probiotic and different levels of Spirulina had no significant effect on laying performance of Japanese quails (p>0.05). Probiotic supplement increased Lactobacil bacteria population in laying quails ileum under heat stress (p 0.05). Different levels of SP decreased Escherichia coli population in laying quails ileum suffering heat stress (p 0.05).SP at the level of 0.5% caused the lowest blood Malondialdehyde level, heterophil, and H/L ratio (p 0.05).However, HSP70 gene expression in the heart or the liver of laying quails was not different (p>0.05). In conclusion, the results of the present study revealed that SP at the level of 0.5 % has the potential to be considered as a probiotic alternative in the diet of laying quails suffering heat stress condition.(AU)

Arthrospira (Spirulina) Platensis Can Be Considered as a Probiotic Alternative to Reduce Heat Stress in Laying Japanese Quails

This study was conducted to investigate the effects of Arthrospira platensis (Spirulina platensis, SP) on feed intake, feed conversion ratio, egg weight, hen day egg production, intestinal microflora, heat stress biomarkers, and HSP70 gene expression in laying Japanese quails (Coturnix coturnix japonica) suffering heat stress condition. A total of 250 female quails were allocated to 5 treatments, 5 replicates and 10 birds in each replicate in a completely randomized design. Experimental treatments included: 1) basal diet, 2) basal diet+ 0.03 % probiotic, 3) basal diet+ 0.1 % SP, 4) basal diet+ 0.3 % SP, 5) basal diet+ 0.5 % SP. During the last 6 days of the experiment, the quails were exposed to 8h of 34±1°C. The birds had free access to feed and water during the experiment. The results showed that using probiotic and different levels of Spirulina had no significant effect on laying performance of Japanese quails (p>0.05). Probiotic supplement increased Lactobacil bacteria population in laying quails ileum under heat stress (p 0.05). Different levels of SP decreased Escherichia coli population in laying quails ileum suffering heat stress (p 0.05).SP at the level of 0.5% caused the lowest blood Malondialdehyde level, heterophil, and H/L ratio (p 0.05).However, HSP70 gene expression in the heart or the liver of laying quails was not different (p>0.05). In conclusion, the results of the present study revealed that SP at the level of 0.5 % has the potential to be considered as a probiotic alternative in the diet of laying quails suffering heat stress condition.

Supplementation with Spirulina platensis Modulates Aortic Vascular Reactivity through Nitric Oxide and Antioxidant Activity.

The possible mechanism is involved in the effects of Spirulina platensis on vascular reactivity. Animals were divided into sedentary group (SG) and sedentary groups supplemented with S. platensis at doses of 50 (SG50), 150 (SG150), and 500 mg/kg (SG500). To evaluate reactivity, cumulative concentration-response curves were constructed for phenylephrine and acetylcholine. To evaluate the involvement of the nitric oxide (NO) pathway, aorta tissue was preincubated with L-NAME and a new curve was then obtained for phenylephrine. Biochemical analyses were performed to evaluate nitrite levels, lipid peroxidation, and antioxidant activity. To contractile reactivity, only SG500 (pD2 = 5.6 ± 0.04 vs. 6.1 ± 0.06, 6.2 ± 0.02, and 6.2 ± 0.04) showed reduction in phenylephrine contractile potency. L-NAME caused a higher contractile response to phenylephrine in SG150 and SG500. To relaxation, curves for SG150 (pD2 = 7.0 ± 0.08 vs. 6.4 ± 0.06) and SG500 (pD2 = 7.3 ± 0.02 vs. 6.4 ± 0.06) were shifted to the left, more so in SG500. Nitrite was increased in SG150 and SG500. Lipid peroxidation was reduced, and oxidation inhibition was increased in all supplemented groups, indicating enhanced antioxidant activity. Chronic supplementation with S. platensis (150/500 mg/kg) caused a decrease in contractile response and increase in relaxation and nitrite levels, indicating greater NO production, due to decreased oxidative stress and increased antioxidant activity.

Nannochloropsis sp. and Spirulina sp. as a Source of Antifungal Compounds to Mitigate Contamination by Fusarium graminearum Species Complex.

Phenolic (free, conjugated and bound) and carotenoid extracts from microalgae Nannochloropsis sp. and Spirulina sp. were investigated regarding their potential to mitigate contamination by Fusarium complex fungal pathogens. Free phenolic acid extracts from both microalgae were the most efficient, promoting the lowest mycelial growth rates of 0.51 cm day- 1 (Spirulina sp.) and 0.78 cm day- 1 (Nannochloropsis sp.). An experiment involving natural free phenolic acid extracts and synthetic solutions was carried out based on the natural phenolic acid profile. The results revealed that the synthetic mixtures of phenolic acids from both microalgae were less efficient than the natural extracts at inhibiting fungal growth, indicating that no purification is required. The half-maximal effective concentration (EC50) values of 49.6 µg mL- 1 and 33.9 µg mL- 1 were determined for the Nannochloropsis and Spirulina phenolic acid extracts, respectively. The use of phenolic extracts represents a new perspective regarding the application of compounds produced by marine biotechnology to prevent Fusarium species contamination.