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Pollution from crude oil and its derivatives poses a serious threat to human health and ecosystems, with accidental spills causing substantial damage. Biodegradation, using microorganisms to break down these contaminants, presents a promising and cost-effective solution. Exploring and utilizing new bacterial strains from underexplored habitats could improve remediation efforts at contaminated sites. This study aimed to evaluate the hydrocarbon biodegradation capacity of bacteria isolated from agricultural soils in Huamachuco, Peru. Soil samples from Oca crops were collected and bacteria were isolated. Biodegradation assays were conducted using diesel as the sole carbon source in the Bushnell Haas Mineral medium. Molecular characterization of the 16S rRNA gene identified four strains. Diesel biodegradation assays at 1% concentration were performed under agitation conditions at 150 rpm and 30 °C, and monitored on day 10 by measuring cellular biomass (OD600), with hydrocarbons analyzed by gas chromatography. The results showed Pseudomonas protegens (PROM2) achieved the highest efficiency in removing total hydrocarbons (91.5 ± 0.7%). Additionally, Pseudomonas citri PROM3 and Acinetobacter guillouiae ClyRoM5 also demonstrated high capacity in removing several individual hydrocarbons. Indigenous bacteria from uncontaminated agricultural soils present a high potential for hydrocarbon bioremediation, offering an ecological and effective solution for soil decontamination. [ABSTRACT FROM AUTHOR]

Chitin, an abundant biopolymer with potential applications in agriculture, medicine, and bioremediation, is conventionally extracted using chemical methods that have environmental disadvantages. This study investigates the extraction of chitin from Litopenaeus vannamei shrimp waste by one-step fermentation using the bacterial strains Pseudomonas aeruginosa QF50 and Serratia sp. QCS23. A total of 4 kg of shrimp waste was treated by fermentation with culture media enriched with different concentrations of glucose (1, 5, and 10%) for 7 days at 25 °C, followed by purification and characterization processes using infrared spectroscopy and X-ray diffraction. The results demonstrated an increase in the yield of crude chitin proportional to the glucose concentration, reaching a maximum of 76.81 ± 7.64% for Pseudomonas aeruginosa QF50 and 71.30 ± 1.16% for Serratia sp. QCS23. Both strains showed high efficiencies in deproteinization (80–87%) and demineralization, with significant improvements especially shown at high glucose concentrations. Structural characterization confirmed the presence of the spectral characteristics of α-chitin, with crystallinity indices of 81% and 71% for chitins obtained with Pseudomonas aeruginosa QF50 and Serratia sp. QCS23, respectively. This study concludes that single-step fermentation with Pseudomonas aeruginosa QF50 and Serratia sp. QCS23 is an effective and sustainable method for the extraction of high-quality chitin from shrimp exoskeleton waste, offering a promising alternative to traditional chemical methods. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoate (PHA) has unique physicochemical and mechanical properties like conventional plastics; however, its high production cost makes it unsuitable for commercial use. Therefore, the purpose of the present study is to use low-cost and bioavailable raw materials such as agro-industrial waste of asparagus husk, as substrate for obtaining PHA by Bacillus thuringiensis. The proximal characteristics and structural carbohydrates of the waste were previously determined using HPLC. The pretreatment conditions were optimized using a Plackett-Burman design and response surface of the central compounds, evaluating temperature, %NaOH, time, % solid/liquid and solvent. Likewise, the enzymatic hydrolysates of the optimal conditions of the pretreatment were used, using an enzymatic solution with cellulase activity at 45°C at 100 rpm for 72 h. To produce PHA, a mineral-based medium, supplemented with enzymatic hydrolysate from the optimal pretreatment, was utilized. This study examined the effects of varying initial inoculum concentrations (0.25, 0.5, and 0.75 g/L) and percentages of enzymatic hydrolysate supplement (%, v/v). The process was conducted at 30°C and agitated at 125 rpm for 72 h. Maximum production of PHA was obtained with 0.138 g/L from an initial inoculum of 0.75 g/L of B. thuringiensis and a 47% supplement of the enzymatic hydrolysate. The PHA biopolymer was identified by its chemical characteristics by FTIR and correlated by HPLC with a standard. This study contributes to the use of agro-industrial waste to obtain biologically-based bioplastic through a low-cost process aligned with the circular economy strategy. [ABSTRACT FROM AUTHOR]

Bacterial cellulose is a biomaterial known for its physical and mechanical properties, including its high mechanical strength, water retention capacity, and biocompatibility. Its production from various carbohydrates has been widely studied, aiming to find more efficient and cost-effective culture media. This study investigated the production of bacterial cellulose from agroindustrial asparagus peel waste by Komagataeibacter rhaeticus QK23. A strain of QK23 was isolated and cultivated from a kombucha tea, identified based on morphological and molecular characteristics using the 16S rRNA gene. The waste was hydrolyzed and converted into fermentable sugars. Using the response surface methodology, the inoculum dose (1–20%) and incubation time (3–25 days) were evaluated concerning bacterial cellulose yield. The results demonstrated that with an optimal inoculum dose of 10.5% and an incubation time of 25 days, a production of 2.57 g/L was achieved. It was characterized as similar to type I cellulose, exhibiting a high degree of crystallinity (81.89%) and suitable morphological properties, evidenced by a fiber size of 178 nm and a surface roughness of 27.05 nm. Converting asparagus waste into bacterial cellulose is a sustainable and effective strategy that promotes the development of advanced biomaterials in biotechnology research. [ABSTRACT FROM AUTHOR]

Phenolic compounds have gained international interest due to their carcinogenic, toxic, and bioaccumulative properties, causing adverse effects in both animals and humans. As a result, there is a growing interest in finding alternative and eco-friendly treatment routes for phenol by exploring new microbial cultures with potential adaptation and biodegradation capabilities. In this study, the phenol removal efficiency of Yarrowia lipolytica YQ22 under laboratory conditions was determined. The YQ22 strain was obtained from diesel samples from a fuel station in Trujillo, Peru, isolated through serial dilutions on Sabouraud agar, and identified through its morphological characteristics using microscopy and molecular analysis by polymerase chain reaction of the ribosomal DNA internal transcribed spacer (ITS) and 5.8S regions. In the treatment, the effect of pH (5, 6 and 7) and temperature (25°C, 30°C and 35°C) on phenol removal with 2% (v/v) inoculum of Yarrowia lipolytica from 48-hour growth was evaluated. Phenol concentration was measured by high-performance liquid chromatography. A maximum phenol removal percentage of 61.18 was obtained for YQ22 at 30°C, pH 5 and 120 rpm during 48 hours. These findings demonstrate the ability of Yarrowia lipolytica to remove phenol and suggest its potential use in the field of bioremediation of phenolic compounds and their derivatives. [ABSTRACT FROM AUTHOR]

Microorganisms' degradation of agro-industrial waste produces bad odors and greenhouse gases that contribute to global warming. Consequently, eco-friendly, sustainable biotechnological alternatives to this waste are sought to provide additional value, which is why this study's objective was to develop a method of producing unicellular proteins from artichoke and asparagus agro-industrial waste using Rhodotorula mucilaginosa as a producer organism. Agricultural soil was collected from the Universidad Nacional de Trujillo (Peru), and R. mucilaginosa was isolated and identified using biochemical tests. Proteins and carotenoids were produced from artichokes and asparagus residues using the R. mucilaginosa yeast. Four substrate concentrations (10, 20, 30, and 40%) and a pH range (5–8.1) were used. They were incubated at 30 °C for 72 h. The results showed that protein and carotenoid yield varied according to pH and substrate concentration. Artichoke residues reached a maximum protein yield of 25.98 mg/g and carotenoids of 159.26 μg/g at pH 5–6.6, respectively. Likewise, the asparagus residue showed a maximum protein yield of 20.22 mg/g and a carotenoid yield of 358.05 μg/g at a pH of 7.1 and 6.6, respectively. This study demonstrated the potential of artichoke and asparagus agro-industrial residues for the production of unicellular proteins and carotenoids using R. mucilaginosa. Further, it represents an appropriate alternative to properly managing agro-industrial waste, giving it an economic value. [ABSTRACT FROM AUTHOR]

The carotenoids have vast medical, industrial, dietary, and pharmaceutical importance due to their provitamin A precursor, immunomodulator, antioxidant and photoprotective activity. The purpose of the research was to optimize the production of carotenoids using Rhodotorula mucilaginosa from artichoke agroindustrial waste as a low-cost substrate. The artichokes bracts waste was bleached by sodium hypochlorite (NaClO 2%) and was characterized through whiteness index and FTIR. The bleached artichoke waste (BABW) used in the fermentation went through acid hydrolysis, applying 8% of the bleached artichokes residue and sulfuric acid (2.5%) for 1 h at 90°C, obtaining a greater reduced sugars content at 3.1 g/L. Rhodotorula mucilaginosa was isolated and molecularly identified. The production of carotenoids from a culture media based on hydrolyzed BABW, peptone (0.5%), yeast extract (0.1%) and sodium chloride (0.5%) was evaluated at different conditions of pH (5-8) and agitation speed (80-160 rpm) applying the surface response methodology by a rotational central compound design. The best carotenoids performance obtained had 2968.95 µg/L VVC and 1228.53 µg/g TFC at pH 5, 120 rpm and 30°C for 72 h. The chemical characterization of the extracted carotenoids was confirmed by UV-VIS and Raman spectroscopy methods. The results suggest that Rhodotorula mucilaginosa is capable of producing carotenoids from artichoke waste fermentation, providing a low-cost and sustainable alternative route for use in the global market. [ABSTRACT FROM AUTHOR]

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Copyright of Revista del Cuerpo Médico del Hospital Nacional Almanzor Aguinaga Asenjo is the property of Cuerpo Medico del Hospital Nacional Almanzor Aguinaga Asenjo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Equisetum arvense (Equisetaceae) is a plant that has anti-inflammatory effects due to its phytochemical compounds such as flavonoids, which act at the level of proinflammatory cytokines, mainly TNF-α. However, other species of Equisetum are known in Peru, of which these effects have not been demonstrated. One of these species is Equisetum bogotense, from which the flavonoids were extracted and inoculated in Mus musculus BALB / c. These flavonoids acted on the levels of TNF-α produced in the inflammation experimentally induced in Mus musculus BALB / c by the inoculation of carrageenans. For the quantification of TNF-α levels the ELISA test was performed, obtaining that the flavonoids reduced the levels of TNF-α, however there was no significant difference between the concentrations used. [ABSTRACT FROM AUTHOR]