Stress influenced increase in phenolic content and radical scavenging capacity of Rhodotorula glutinis CCY 20-2-26

Fermentative Production of β-Carotene from Sugarcane Bagasse Hydrolysate by Rhodotorula glutinis CCT-2186

Β-Carotene is a red-orange pigment that serves as a precursor to important pharmaceutical molecules like vitamin A and retinol, making it highly significant in the industrial sector. Consequently, there is an ongoing quest for more sustainable production methods. In this study, glucose and xylose, two primary sugars derived from sugarcane bagasse (SCB), were utilized as substrates for β-carotene production by Rhodotorula glutinis CCT-2186. To achieve this, SCB underwent pretreatment using NaOH, involved different concentrations of total solids (TS) (10%, 15%, and 20%) to remove lignin. Each sample was enzymatically hydrolyzed using two substrate loadings (5% and 10%). The pretreated SCB with 10%, 15%, and 20% TS exhibited glucose hydrolysis yields (%wt) of 93.10%, 91.88%, and 90.77%, respectively. The resulting hydrolysate was employed for β-carotene production under batch fermentation. After 72 h of fermentation, the SCB hydrolysate yielded a β-carotene concentration of 118.56 ± 3.01 mg/L. These findings showcase the robustness of R. glutinis as a biocatalyst for converting SCB into β-carotene.

Bioactive compounds and antioxidant activities in the agro-industrial residues of acerola (Malpighia emarginata L.), guava (Psidium guajava L.), genipap (Genipa americana L.) and umbu (Spondias tuberosa L.) fruits assisted by ultrasonic or shaker extraction

The aim of this study was to analyze the residue powders of Malpighia emarginata L., Psidium guajava L., Genipa americana L. and Spondias tuberosa L. regarding their total phenolic compounds contents, antioxidant activity (ABTS, DPPH and FRAP), soluble sugars, carotenoids, organic acids by HPLC-DAD/RID and individual phenolic compounds by the UPLC-QDa-MS system. The genipap residue had a high content of soluble sugars (422.72 ± 19.15 mg.g^-1 DW), with a higher content of sucrose (170.83 ± 10.89 mg.g^-1 DW). Nystose was found in the residues of guava (6.59 ± 0.56 mg.g^-1 DW) and umbu (65.61 ± 2.31 mg.g^-1 DW). The residues of acerola and umbu showed contents of β-carotene of 5.84 ± 0.01 mg.g^-1 DW and 0.10 ± 0.05 mg.g^-1 DW, respectively while high concentration (1116.00 ± 2.00 mg.100 g^-1 DW) of tartaric acid was found in acerola residue and quinic acid (6340 ± 104.00 mg.100 g^-1 DW) in umbu residue. Acetone (80%) and ultrasonic extraction were the best conditions for the residues of acerola, guava and genipap, however, for the umbu residue, extraction with shaker showed better results. The acerola and umbu residues showed higher yields of total phenolics, the values being 378.69-444.05 mg GAE.100 g^-1 DW and 326.14-404.36 mg GAE.100 g^-1 DW, respectively, as well as antioxidant activity. Naringenin was the individual phenolic compound with the highest concentration in the residue of acerola and genipap, vanillin in guava and rutin in umbu. Thus, residues powders from acerola, guava, genipap and umbu constitute potential sources of bioactive compounds, which could be used in the food, pharmaceutical and cosmetic industries.

Bioactive profile, free-radical scavenging potential, DNA damage protection activity, and mycochemicals in Aspergillus awamori (MTCC 548) extracts: a novel report on filamentous fungi

Biomass of Aspergillus awamori was investigated for mycochemicals, total phenolic compounds (TPC), condensed tannin content (CTC), free-radical scavenging potential (FRSP), and DNA damage protection activity. FRSP was determined using DPPH, ABTS, FRAP (Ferric reducing antioxidant power), metal chelating activity, and cupric reducing antioxidant capacity) assays. Water (Aq), aqueous ethanol 50% (AqE), and methanol were used as extraction phase at 44.5 °C for 23.8 min. AqE shows the presence of maximum mycochemicals (coumarins, glucose, saponins, flavonoids, and tannin). Further quantitative analysis shows maximum TPC (23.17 mg GAE/g dwb) in AqE and CTC (.89 mg CE/g dwb) in ME. Qualitative and quantitative analysis for identification of specific bioactive compound in AqE was carried out using HPLC. HPLC analysis confirmed the presence of bioactive compounds: p'-Coumaric acid (5.96 mg/g dwb), cinnamic acid (4.31 mg/g dwb), gallic acid (2.27 mg/g dwb), and ascorbic acid (.98 mg/g dwb). All the extracts show significant DNA damage protection activity; however, AqE showed the maximum activity. Pearson correlations were also calculated to find the relationships between bioactive compounds and antioxidant potential.