Search Results (4)

Efficient biomass harvesting remains one of the primary barriers to the commercial feasibility of large-scale microalgal production. This study investigates the effect of different culture media on the surface physicochemical properties of Tetradesmus sp., with emphasis on their role in natural aggregation. Cultures were grown for 30 days under controlled light and temperature conditions using Blue Green 11 (BG11), Tris–acetate–phosphate (TAP), and deionized water supplemented with Bayfolan^® fertilizer. Surface hydrophobicity was assessed through microbial adhesion to solvents (MATS) and contact angle analysis, electrokinetic properties were evaluated by zeta potential measurements, and cell surface chemistry was characterized by attenuated total reflectance (ATR) sampling methodology for Fourier Transform Infrared (FTIR) spectroscopy. Across all treatments, Tetradesmus sp. exhibited inherent hydrophobicity, but Bayfolan^® supplementation yielded the highest contact angle (49.0 ± 0.9°) and the least negative free energy of interaction (ΔGsws = −26.36 mJ·m⁻²), indicating a stronger tendency toward self-aggregation. Zeta potential values remained consistently negative (−10 to −14 mV), with no significant variation among media, suggesting that hydrophobic interactions rather than electrostatic forces govern aggregation. ATR-FTIR spectra confirmed the presence of lipids, proteins, and carbohydrates, with changes in peak intensities reflecting metabolic adjustments to media composition. These results demonstrate that low-cost Bayfolan^® supplementation enhances surface hydrophobicity and aggregation, providing a sustainable strategy to facilitate biomass recovery and reduce harvesting costs in microalgal biorefineries. Full article

The alga Chondracanthus chamissoi, commonly known as “yuyo” or “mococho” is found along the coasts of Peru and Chile. Due to its multiple applications in industrial, health, pharmaceutical, and productive sectors, its demand has increased, leading to the uncontrolled exploitation of natural banks and negatively impacting marine ecosystems. This experimental study evaluated the viability of propagating C. chamissoi propagules using the foliar fertilizer Bayfolan^® from Bayer, as well as its continuous, non-seasonal cultivation in La Ramada. This initiative aims to establish a productive area in La Libertad to meet the needs of national and international markets, reducing the indiscriminate exploitation of seaweed in natural banks. The results indicated that continuous cultivation is feasible, with growth rates of 0.0369 and 0.0388 g.day⁻¹ (0% Bayfolan) and 0.0397 and 0.0399 g.day⁻¹ (1% Bayfolan) during propagule propagation. Slight statistically significant differences were observed in final biomass between 0% and 1% Bayfolan treatments, and Bayfolan use reduced healing time by seven days. Nutritional and microbiological assays confirmed that fresh “yuyo” is suitable for human consumption; hence, La Ramada provides suitable physical–chemical and microbiological conditions for extracting and cultivating hydrobiological species, offering a viable alternative to the seasonal overexploitation of the algae and potential economic benefits for coastal families. Full article

Given the need to improve bioenergy production processes, it is necessary to focus on low-cost culture media and environmental conditions of radiation and temperature. The Scenedesmus dimorphus species was cultured in eutrophicated lagoon water and Bayfolan 0.3% as culture media under four photoperiods with the objective of evaluating the biomass productivity, bioremediation capacity and influence of illumination on the composition and lipid content. It is concluded that the increase of light hours in the culture with eutrophicated lagoon water produces a decrease in the biomass productivity and COD removal percentage. The highest biomass productivity was obtained in photoperiod F1 (10.5:13.5) hours L:O, 0.053 ± 0.0015 g/L day and a removal of 95.6%. Bayfolan 0.3% with F2 (11.5:12.5) and F3 (12.5:11.5) did not show significant differences in the biomass productivity and COD removal. The increase in light hours in the photoperiod induced an increase of 1.01% and 2.84% of saturated fatty acids and 0.8% and 2.14% of monounsaturated fatty acids, as well as a decrease of 3.85% and 2.88% of polyunsaturated fatty acids in eutrophicated lagoon water and Bayfolan 0.3%, respectively. Full article

Chondracanthus chamissoi is an edible red seaweed with a high hydrocolloid content and food industry demand. This situation has led to a decline in their populations, especially in Peru. An alternative culture method based on the formation of secondary attachment discs (SADs) has shown several advantages over traditional spore strategies. However, there are still scarce reports of the SAD method in Peru. This work aimed to evaluate the best conditions for C. chamissoi maintenance prior to SAD development and the effect of locality on SAD formation using scallop shells as a substratum. Experiments were conducted with material collected from five localities in Pisco (Ica, Peru). Our results showed that the best conditions for C. chamissoi maintenance were: (1) fertilized seawater with Bayfolan^® (0.2 mL L⁻¹); and (2) medium exchange every two days or weekly. These conditions reduced the biomass loss to 9.36–11.14%. Most localities showed a similar capacity to produce SADs (7–17 SADs shell⁻¹). However, vegetative algae, especially Mendieta, tended to present a higher number of SADs. Vegetative fronds also showed lower levels of necrosis and deterioration compared to cystocarpic and tetrasporophytic samples. This study shows the technical feasibility of culturing C. chamissoi through SADs for developing repopulation and/or intensive cultivation projects in Peru. Full article