Encapsulation of polyketide colorants in chitosan and maltodextrin microparticles.

This study aimed to encapsulate Talaromyces amestolkiae colorants in maltodextrin and chitosan microparticles using the spraydrying technique and to evaluate the biopolymers' capacities to protect the fungal colorant against temperature (65 °C) and extreme pH (2.0 and 13.0). The compact microparticles exhibited smooth or indented surfaces with internal diameters ranging between 2.58-4.69 µm and ζ ~ -26 mV. The encapsulation efficiencies were 86 % and 56 % for chitosan and maltodextrin microparticles, respectively. The shifted endothermic peaks of the free colorants indicated their physical stabilization into microparticles. The encapsulated colorants retained most of their absorbance (compared to the 0 h) even after 25 days at 65 °C. Contrary, the free colorant presented almost no absorbance after 1 day under the same conditions. Colorants in chitosan and maltodextrin matrices also partially maintained their colorimetric and fluorometric properties at acidic pH. However, only maltodextrin improved the resistance of the red colorant to alkaline environments. For the first time, the potential of polysaccharide-based microparticles to preserve polyketide colorants was demonstrated using 3D fluorescence. Therefore, this study demonstrated an alternative in developing functional products with natural color additives.

Nanoencapsulation of hybrid crude palm oil Unaué HIE OxG with jackfruit by-products as encapsulants: A study of cellular antioxidant activity and cytotoxicity in Caco-2 cells.

Hybrid crude palm oil (HCPO) HIE OxG is notable for its abundance of carotenoids, tocopherols, and tocotrienols. Investigating cellular antioxidant activity (CAA) and the non-cytotoxicity of oil nanoparticles is crucial for understanding the behavior of these phytochemicals in biological systems and ensuring the safety of products. Nanoparticles of HCPO, encapsulated with jackfruit by-products were produced and characterized for CAA and cytotoxicity in Caco-2 cells. The nanoparticles exhibited nanoscale diameters (<250 nm), uniform distribution and stability (polydispersity index < 0.25; zeta potential JSF-NP -12.46 ± 0.15 mV and JAF-NP -13.73 ± 1.28 mV). JSF-NP and JAF-NP demonstrated superior CAA compared to the free HCPO across all concentrations, without inducing cytotoxic effects on differentiated Caco-2 cells. This study underscores the importance of investigating the CAA of edible oil nanoparticles, with non-cytotoxicity indicating biological safety and the potential to safeguard intestinal epithelial cells. Thus, JSF-NP and JAF-NP emerge as promising delivery systems for future HCPO applications.

Insect residues as an alternative and promising source for the extraction of chitin and chitosan.

This work aimed to obtain and characterize chitin and chitosan extracted from the rearing residues of Tenebrio molitor, Zophobas morio, and Blaptica dubia insects in different growth stages in the same rearing cycles chitin and chitosan yielded 11.21 %-20.89 % and 6.26 %-7.07 %, respectively. The deacetylation degrees of chitosan ranged from 75.75 %-89.21 %, and the solubilities from 69.88 %-94.39 %. Infrared spectroscopy corroborated the acquisition of chitin and chitosan and can be used as a semi-quantitative technique for determining the degree of chitosan deacetylation. The X-ray diffraction profiles revealed the presence of α-chitin, and the relative crystalline indices ranged from 65.9 %-89.2 %. Typical TG profiles with two thermal events are observed for chitin and chitosan samples with different residue contents from the extraction procedure. The chitosan solutions exhibited pseudoplastic behavior, with apparent viscosities ranging from 195.96 to 249.86 mPa.s. The characterization results of the biopolymers extracted from insect residues were similar to those obtained from conventional sources. The growth stage influenced the chitin yield and crystallinity index. The results of this study reinforce the feasibility of using alternative sources of chitin and chitosan, providing the use of waste from insect farms and contributing to sustainability and a circular economy.

Effect of Addition of Cross-Linked Starch on the Properties of Degraded PBAT Poly(butylene adipate-co-terephthalate) Films.

This work aimed to evaluate the properties of butylene adipate-co-terephthalate (PBAT) degraded after 1800 days of storage (DPBAT) by preparing blends (films) with crosslinked starch (Cm) through extrusion and thermocompression. Different ratios of DPBAT:Cm (70:30, 60:40, and 50:50 m/m) were prepared. The incorporation of Cm into DPBAT significantly changed the properties of the films by making them stiffer (increasing Young's modulus by up to 50%) and increasing the thermal resistance of DPBAT. The presence of crosslinked starch in the films made them less hydrophobic (with decreased contact angle and increased moisture content), but these parameters did not vary linearly with changes in the content of crosslinked starch in the blend (DPBAT:Cm). The microscopic images show an inhomogeneous distribution of Cm granules in the DPBAT matrix. Thus, the films prepared with PBAT show a significant decrease in their mechanical parameters and heat resistance after long-term storage. However, the preparation of blends of degraded DPBAT with crosslinked starch promoted changes in the properties of the films prepared by thermocompression, which could be useful for disposable packaging.

Technological and Scientific Prospection on Pigments Produced by Microorganisms.

BACKGROUND: Interest in natural pigments has grown due to the negative aspects caused by synthetic options, which trigger damage to the body and the environment. Research with natural pigments produced by microorganisms becomes viable in relation to other pigments extracted from animals or plants, as microorganisms have advantages in terms of versatility and productivity. Thus, production technologies are protected by patents. METHODS: To evaluate the evolution of research and technological development on producing natural pigments by different microorganisms through scientific and technological prospection. Scientific prospecting was done by searching articles published from 2010 to 2020 in the Scopus, Science Direct, and Web of Science databases. Technological prospecting was carried out with patents obtained from the European Patent Office (ESPACENET) database. RESULTS: The searches were based on the keywords "pigment" and "dye" crossed with microalgae, fungi, bacteria and yeast. A total of 2.811 articles and 451 patents were selected. Scientific prospecting has shown interest in alternative cultivation media, and among the microorganisms that produce pigments, fungi and microalgae are the most studied. CONCLUSION: Technological prospecting showed that 375 (83%) recovered patent documents refer to the protection of pigment extraction and production techniques and that the largest patent holders are private companies, followed by Chinese universities.

Innovation in Alternative Food Sources: A Review of a Technological State-of-the-Art of Insects in Food Products.

Insects present great potential for the food industry due to their easier rearing conditions and high nutritional value, in comparison with traditional livestock. However, there is a lack of evaluation of the technological status of food products developed with edible insects. Therefore, this study aims to analyze the emergent technological and scientific applications of edible insects in the food industry through a prospective study of patent documents and research articles. Espacenet was used as a research tool, applying the terms Insect, Pupa, Larva, or Nymph and the codes A23L33 and A23V2002. A total of 1139 documents were found-341 were related to the study. Orbit® was used to evaluate technological domains and clusters of concepts. Scopus database research was performed to assess the prevalence of insect research, with the term "edible and insect*". The main insects used were silkworms, bees, beetles, mealworms, crickets, and cicadas. Protein isolates were the predominant technology, as they function as an ingredient in food products or supplements. A diverse application possibility for insects was found due to their nutritional composition. The insect market is expected to increase significantly in the next years, representing an opportunity to develop novel high-quality/sustainable products.

Utilization of Agro-Industrial Residues in the Rearing and Nutritional Enrichment of Zophobas atratus Larvae: New Food Raw Materials.

Edible insects are a potential alternative food source of high feed conversion efficiency and protein content. Zophobas atratus is an edible insect that adapts to different diets, enabling sustainable rearing by adding value to by-products and agro-industrial residues. This study aimed to evaluate the performance and nutritional characterization of Zophobas atratus larvae fed with different proportions of grape residue. Physicochemical analysis of the diets and larvae (AOAC procedures), fatty acid profile (chromatographic techniques), metals and non-metals (inductively coupled plasma optical emission spectrometry), larval mass gain, feed conversion efficiency, and mortality rate were assessed. The replacement of 25% of the conventional diet with grape residue increased lipid, ash, and fiber contents and reduced protein, carbohydrates, and energy. It promoted greater mass gain, lower mortality rate, and reduced larval growth time by 51%. Among the replacements, 25% resulted in the second-highest content of calcium, sodium, magnesium, and zinc, and the lowest content of potassium and phosphorus in the larvae. The 100% replacement resulted in the highest amounts of C18:2n6 (27.8%), C18:3n3 (2.2%), and PUFA (30.0%). Replacing 25% of the conventional diet with grape residue is equivalent to the conventional diet in many aspects and improves several larvae performance indices and nutritional values.

Analysis and Modeling of Innovations in the Global Microalgae Lipids Market.

Microalgae lipids offer numerous advantages over those of plants and animals, enabling the sustainable commercialization of high value-added products in different markets. Although these markets are in a vertiginous annual expansion, technological life cycle modeling is a tool that has been rarely used for microalgae. Life cycle modeling is capable of assisting with decision-making based on data and is considered as a versatile model, usable in multiple software analyzing and diagnostic tasks. Modeling technological trends makes it possible to categorize the development level of the market and predict phase changes, reducing uncertainties and increasing investments. This study aims to fill this gap by performing a global analysis and modeling of microalgal lipid innovations. The Espacenet and Orbit platforms were used by crossing the keywords "microalgae", "lipid*", and the IPC code C12 (biochemistry and microbiology). Different sigmoid growth models were used in the present study. A successive repetition of the Chlorella genus category was found in the keyword clusters regarding extraction and separation of lipids. The life cycle S curve indicates a market starting at the maturity phase, where the BiDoseResp model stands out. The main countries and institutions at the technological forefront are shown, as well as potential technological domains for opening new markets.

Lithium bioaccumulation in Lentinus crinitus mycelia grown in media with different lithium sources and pH values.

Lentinus crinitus bioaccumulates lithium in mycelia, but bioaccumulation may be affected by pH of the culture medium. Lithium is used in clinical practice as a mood stabilizer and antidepressant. This study aimed to assess the effect of culture medium pH and lithium source (LiCl or Li2CO3) on lithium bioaccumulation in vegetative mycelia of L. crinitus grown in malt extract broth. Lentinus crinitus U9-1 was cultured in malt extract broth supplemented with Li2CO3 or LiCl (50 mg L-1 lithium) in the pH range of 3.0 to 6.0. The pH was adjusted using HCl solution. The results showed that medium pH affected mycelial biomass production, lithium bioaccumulation in mycelial biomass, and lithium transfer from the culture medium to mycelial biomass. The effect of lithium source on the bioaccumulation capacity of mycelial biomass varied according to pH. At pH 4.0, both lithium sources stimulated mycelial biomass production compared to the control without the addition of lithium. At pH 5.5, Li2CO3 provided the highest lithium bioaccumulation in mycelial biomass. Lithium transfer from the culture medium to mycelia was highest in Li2CO3-supplemented cultures at pH 4.5. LiCl reduced hyphal width compared with Li2CO3 and the control. However, pH and lithium sources did not affect the formation of clamp connections in hyphae. For the first time, the influence of the pH of the culture medium on lithium bioaccumulation by Lentinus crinitus is reported. Finally, we conclude that the culture medium pH affected lithium transfer and bioaccumulation in mycelial biomass differently depending on the lithium source. Additionally, we report the presence of clamp connections in the hyphae of L. crinitus as an indicator of even growth.

Long-term cryopreservation of Lentinus crinitus strains by wheat grain technique.

Lentinus crinitus (Basidiomycota: Polyporales) is a saprophytic fungus with biotechnological importance described more than 20 years ago. However, there are few studies on the long-term preservation of this basidiomycete. Cryopreservation is a long-term storage technique that reduces the metabolic activity of microorganisms, but its success depends on the adjustment of the freezing process, the cryoprotectants, and the protective substrates for each species. This study aimed to assess the mycelial viability and genetic stability of L. crinitus strains cryopreserved at -86 °C for two years by the wheat grain technique using different cryoprotectants and freezing methods. Three strains of L. crinitus (U9-1, U13-5, and U15-12) were subjected to different concentrations and types of cryoprotectants (dimethyl sulfoxide, glycerol, glucose, and sucrose), freezing methods such as immediate freezing from 25 to -86 °C and progressing freezing from 25 to -86 °C in a freezing container with isopropyl alcohol to control the rate of cell freezing at -1 °C min-1, protective substrate (wheat grain and 2% malt extract agar), and cryopreservation period (1, 6, 12, and 24 months). After thawing, samples were evaluated for mycelial viability, time to mycelial recovery, mycelial stability, and genetic stability of the fungus. All techniques achieved effective cryopreservation at -86 °C, mainly with the wheat grain technique. All cryoprotectants (3.5% glycerol, 1.5% dimethyl sulfoxide, 25% sucrose, and 5% glucose), freezing methods (immediate and gradual), and protective substrate (wheat grain and malt extract agar) were effective for cryopreservation of the three L.crinitus strains in an ultra-low temperature freezer for two years. Mycelial viability, mycelial stability, and genetic stability of the fungus were not affected after two-year cryopreservation, evidencing the robustness of the long-term cryopreservation technique and the fungus.

Basidiocarp structures of Lentinus crinitus: an antimicrobial source against foodborne pathogens and food spoilage microorganisms.

Lentinus crinitus basidiocarps are an alternative to antimicrobials, but the stipe (24% basidiocarp) is discarded even with potential antimicrobial activity. This study evaluated the antimicrobial activity of L. crinitus basidiocarp pileus and stipe extracts against foodborne pathogens and food spoilage microorganisms. Basidiocarps of L. crinitus were grown in sugarcane bagasse and rice husks and the pileus and stipe methanolic extract was analyzed by broth microdilution method for antimicrobial activity against eight bacteria and eight fungi. The minimum bactericidal concentration values for pileus and stipe ranged from 0.40 to 0.50 mg mL- 1, for streptomycin from 0.10 to 0.50 mg mL- 1, and for ampicillin from 0.40 to 1.20 mg mL- 1. The minimum fungicidal concentration values for pileus and stipe ranged from 0.06 to 0.60 mg mL- 1, for bifonazole from 0.20 to 0.25 mg mL- 1, and for ketoconazole from 0.30 to 3.50 mg mL- 1. Extracts had bacteriostatic, bactericidal, fungistatic and fungicidal activity against all microorganisms, but with greater efficiency and specificity for some microorganisms. Both pileus and stipe are promising and sustainable alternatives for use in food, agricultural, and pharmaceutical industries.

Physicochemical composition, fatty acid profile and sensory attributes of meat (longissimus lumborum muscle) from Nellore and Nellore-cross bulls.

This study aimed to compare the physicochemical characteristics, fatty acid composition, and sensory attributes of the meat from three genetic groups: Nellore (Nell), ½ Nellore × ½ Angus (NeAn), and » Nellore × » Angus × ½ Senepol (NASe). Longissimus lumborum muscle from 30 slaughtered bulls with a body weight of 549 ± 32.5 kg was used. The water holding capacity was greater for the Nell and NeAn groups than for the NASe group. Meat samples from the NASe group exhibited a higher L* index than those from the NeAn group and lower a* and b* color indexes than those from the Nell group. The meat fatty acid profiles showed that the Nell group had higher concentrations of 12:0, 14:0, 18:1 t11, 14:1 c9, 16:1 c9, 18:1 c9, 18:1 c11, 18:2 c9, t11 (conjugated linoleic acid (CLA)), and 20:3 n-6 polyunsaturated fatty acid (PUFA) than the NeAn and NASe groups. The total saturated (ΣSFA), unsaturated (ΣUFA), and monounsaturated (ΣMUFA) fatty acid concentrations were higher and the ΣPUFA:ΣSFA ratio was lower in the Nell group than in the NeAn group. The Δ9-desaturase C16 activity was significantly higher in the Nell and NASe groups than in the NeAn group. The atherogenicity index (AI) tended to be lower in the crossbreeds than in the Nell breed. The NASe group presented meat with better tenderness, juiciness, and overall acceptance than the Nell and NeAn groups and was therefore the best genetic group for beef production of the tested groups.

Starch chemical modifications applied to drug delivery systems: From fundamentals to FDA-approved raw materials.

Starch derivatives are versatile compounds that are widely used in the pharmaceutical industry. This article reviews the advances in the research on hydrophilic and hydrophobic starch derivatives used to develop drug delivery systems over the last ten years, specifically microparticles, nanoparticles, nanocrystals, hydrogels, and scaffolds using these materials. The fundamentals of drug delivery systems, regulatory aspects, and chemical modifications are also discussed, along with the synthesis of starch derivatives via oxidation, etherification, acid hydrolysis, esterification, and cross-linking. The chemical modification of starch as a means to overcome the challenges in obtaining solid dosage forms is also reviewed. In particular, dialdehyde starches are potential derivatives for direct drug attachment; carboxymethyl starches are used for drug encapsulation and release, giving rise to pH-sensitive devices through electrostatic interactions; and starch nanocrystals have high potential as hydrogel fillers to improve mechanical properties and control drug release through hydrophilic interactions. Starch esterification with alginate and acidic drugs could be very useful for site-specific, controlled release. Starch cross-linking with other biopolymers such as xanthan gum is promising for obtaining novel polyelectrolyte hydrogels with improved functional properties. Surface modification of starch nanoparticles by cross-linking and esterification reactions is a potential approach to obtain novel, smart solid dosages.

Preparation and characterization of C-phycocyanin coated with STMP/STPP cross-linked starches from different botanical sources.

This work aimed to use sodium trimetaphosphate/sodium tripolyphosphate cross-linked potato, banana, corn, cassava, and breadfruit starches as wall materials for C-phycocyanin encapsulation, characterize them and evaluate their in vivo pharmacological effects in an inflammation model. The cross-linked starches were successfully obtained, characterized, and submitted to C-phycocyanin encapsulation by freeze-drying. The characterization of cross-linked starches-C-phycocyanin composites by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetry, and differential scanning calorimetry demonstrated that the C-phycocyanin was encapsulated between amorphous chains of cross-linked starches. Among the five preparations, the cross-linked potato starch presented the highest phosphorous content (0.084%), substitution degree (0.004), water uptake capacity (0.88 g g-1), and C-phycocyanin encapsulation efficiency (67.58%), thus was tested in vivo. The cross-linked potato starch-C-phycocyanin prolonged the antihyperalgesic effects attributed to C-phycocyanin, evaluated by complete Freund's adjuvant (CFA) model. Starch cross-linking promoted the formation of a hydrogel network in swollen state entrapping C-phycocyanin, thus, acting as a barrier to its release to the medium and promoting long-lasting in vivo effects. The combination of chemical modification of starches followed by physical treatment presented itself as a useful tool for the development of pharmaceutical formulations.

Brackish Groundwater from Brazilian Backlands in Spirulina Cultures: Potential of Carbohydrate and Polyunsaturated Fatty Acid Production.

The composition of brackish groundwater from Brazilian backlands contains important elements necessary for metabolism in microalgae. This study evaluated the use of 100% brackish groundwater with different amounts of Zarrouk nutrients for Spirulina sp. LEB 18 cultivation. The growth parameters and biomass composition, including the concentrations of proteins, carbohydrates, ash, lipids, and fatty acids, were evaluated. The best growth parameter results were obtained in the assay using 100% brackish groundwater and only 25% of Zarrouk nutrients, which were equal to those obtained for the control culture. The concentrations of carbohydrates and polyunsaturated fatty acids were increased by as much as 4- and 3.3-fold, respectively, when brackish groundwater was used in the cultures. The lipid profile demonstrated that the biomass had the potential for use in biodiesel production. The use of brackish groundwater is a sustainable, economical way to obtain high-quality biomass for different applications during Spirulina sp. LEB 18 cultivation.

Grape peel (Syrah var.) jam as a polyphenol-enriched functional food ingredient.

In this study, we evaluated the effects of the storage time on the physicochemical properties, bioactive compound content, and antioxidant capacity of jam prepared from grape peel extract to explore its potential as a supplementary food and/or functional ingredient. The ethanolic extract from Syrah var. grape peel exhibited high bioactive compound concentrations and antioxidant activity. The jam stability (prepared with 8.9% of extract) at 14°C was evaluated at 0, 15, 30, 45, and 60 days. The jam was found to contain high concentrations of polyphenolic compounds (137.0 ± 3.2 mg of gallic acid equivalent/100 g), total flavonoids (128.5 ± 23.0 mg of equivalent/100 g), and total anthocyanins (92.5 ± 4.0 mg of cyanidin equivalent/100 g). However, a large reduction in the flavonoid (70%-90%), anthocyanin (29%-35%), and phenolic (23%-30%) content was observed during storage. The free radical-scavenging activity (DPPH-), ferric reducing antioxidant power (FRAP), and ß-carotene-linoleic acid assays revealed the great antioxidant potential of the jam prepared from grape peel extract, which exhibited significant levels of radical-neutralizing activity, especially as determined by the DPPH method with EC50 values ranging from 2.3 ± 0.1 to 3.9 ± 0.1 µg/ml. High R 2 values (p > 0.90) were obtained for the correlation between the DPPH results and the concentrations of the compounds of interest. In summary, the high bioactive compound contents and antioxidant capacity of the jam produced from grape peel suggest that it may provide health benefits as a source of natural antioxidants upon incorporation to several food industry products.

Light emitting diodes applied in Synechococcus nidulans cultures: Effect on growth, pigments production and lipid profiles.

Researches about light emitting diodes (LEDs) as energy source in microalgae cultivations has been growing in recent years due to its spectral quality, durability and reduced energy consumption. In this study, green, red and yellow LEDs were evaluated as energy source in Synechococcus nidulans LEB 115 cultures. Productivities and specific growth rates were up to 2.5 times greater than in cultures using fluorescent light. The different LED colors evaluated did not influence the chlorophyll, carotenoid or lipid productions. Biomass cultivated with LEDs showed high amounts of saturated fatty acids (above 48%), which is desirable for biodiesel production. In addition to the Synechococcus nidulans LEB 115 growth stimulation, the application of green, red and yellow LEDs in the cultivations produces potential biomass for biodiesel synthesis and other industrial interest biomolecules utilization.

Valorization of crude glycerol based on biological processes for accumulation of lipophilic compounds.

Bacteria that are capable of accumulating lipids in their cells as storage compounds can also produce polyhydroxyalkanoates of high technological value, depending on the specific culture conditions. The objective of this study was to utilize crude glycerol from biodiesel (CGB) as a substrate, which is a major byproduct from biodiesel production, to produce lipophilic compounds. Bacillus megaterium INCQS 425 was cultivated and evaluated for the production of lipophilic compounds and the properties of these compounds were investigated. Cultivation of the bacteria in a medium with a C:N ratio of 0.60:1 favored the accumulation of lipids by (17.5%) comprising mainly palmitic acid (13.08%), palmitoleic (39.48%), and especially oleic acid (37.02%), which imparts good characteristics to biodiesel. Meanwhile, cultivation of the bacteria in a medium with a C:N ratio of 4:1 favored the accumulation of polyhydroxyalkanoates (PHA) (3.31gL-1) mainly comprising medium and long chain PHA. Low crystallinity (<30%) and excellent thermal properties make them suitable for processes that demand high temperatures, such as extrusion. The lipids produced in the present study had satisfactory oxidative stability for the production of quality biodiesel. The polyhydroxyalkanoates produced in the study are of low cost and have promising thermal properties that justify its technological potential, thereby configuring highly competitive bioproducts.

Effects of spinal cord stimulation on postural control in Parkinson's disease patients with freezing of gait.

Freezing of gait (FoG) in Parkinson's disease (PD) is an incapacitating transient phenomenon, followed by continuous postural disorders. Spinal cord stimulation (SCS) is a promising intervention for FoG in patients with PD, however, its effects on distinct domains of postural control is not well known. The aim of this study is to assess the effects of SCS on FoG and distinct domains of postural control. Four patients with FoG were implanted with SCS systems in the upper thoracic spine. Anticipatory postural adjustment (APA), reactive postural responses, gait and FoG were biomechanically assessed. In general, the results showed that SCS improved FoG and APA. However, SCS failed to improve reactive postural responses. SCS seems to influence cortical motor circuits, involving the supplementary motor area. On the other hand, reactive posture control to external perturbation that mainly relies on neuronal circuitries involving the brainstem and spinal cord, is less influenced by SCS.

Influence of nitrogen on growth, biomass composition, production, and properties of polyhydroxyalkanoates (PHAs) by microalgae.

This study sought to evaluate influence of nitrogen availability on cell growth, biomass composition, production, and the properties of polyhydroxyalkanoates during cultivation of microalgae Chlorella minutissima, Synechococcus subsalsus, and Spirulina sp. LEB-18. The cellular growth of microalgae reduced with the use of limited nitrogen medium, demonstrating that nitrogen deficiency interferes with the metabolism of microorganisms and the production of biomass. The biochemical composition of microalgae was also altered, which was most notable in the degradation of proteins and chlorophylls and the accumulation of carbonaceous storage molecules such as lipids and polyhydroxyalkanoates. Chlorella minutissima did not produce these polymers even in a nitrogen deficient environment. The largest accumulations of the polyhydroxyalkanoates occurred after a 15 days culture, with a concentration of 16% (dry cell weight) produced by the Synechococcus subsalsus strain and 12% by Spirulina sp. LEB-18. Polyhydroxyalkanoates produced by Synechococcus subsalsus and Spirulina sp. LEB-18 presented different thermal and physical properties, indicating the influence of producing strain on polyhydroxyalkanoates properties. The polymers obtained consisted of long chain monomers with 14 to 18 carbon atoms. This composition is novel, as it has not previously been found in PHAs obtained from Synechococcus subsalsus and Spirulina sp. LEB-18.