Biological activity and chemical profile of Brazilian jackfruit seed extracts obtained by supercritical CO2 and low pressure techniques

Green-based methods to obtain bioactive compounds from Ilex guayusa Loes. using polar solvent

Many biological activities have been reported for the Ilex genus. However, few studies in the literature have reported on guayusa. To address this gap in our knowledge, chemical analysis of guayusa leaves was made. Extracts were obtained by applying Soxhlet, maceration, supercritical CO2 and pressurised liquid extraction techniques, using water and ethanol as solvent/cosolvent. Extracts were evaluated for their phenolic content and antioxidant capacity. The chemical profile was obtained from HPLC. In raw guayusa leaves were identified caffeine (2.27 ± 0.05%), protein (15.31 ± 0.07%) and lipids (11.81 ± 0.14%). Extracts presented the highest phenolic content (156.56 ± 1.32 mg GAE g-1) and the best antioxidant activity (EC50= 61.85 ± 0.21 µg mL-1) when water was used as solvent/cosolvent. Through HPLC, three main substances were determined and quantified in the extracts: caffeine, theobromine and 5-caffeoylquinic acid. Based on these results, guayusa may be considered a natural source of compounds with potential application in the food and pharmaceutical industries.

Prospecting Plant Extracts and Bioactive Molecules with Antimicrobial Activity in Brazilian Biomes: A Review

Antimicrobial resistance is currently one of the greatest threats to global health, food security, and development. In this aspect, medicinal plants have been studied to support the development of viable alternatives to prevent and treat infectious diseases. This study aimed to perform a review of the literature comprising the antimicrobial activity of vegetable species from Brazilian biomes. We selected 67 original scientific publications about extracts, fractions, or isolated molecules from plants in the Brazilian biomes, published between 2016 and 2020 in Pubmed, ScienceDirect, and Scielo. Data demonstrated that 98 plant species, especially collected in the Cerrado, Atlantic Forest, and Caatinga biomes, were tested against 40 fungi and 78 bacterial strains. Bioactive fractions of Eucalyptus globulus methanolic stump wood extract were active against Candida albicans and C. tropicalis (MIC 2.50 µg/mL). The catechin purified from Banisteriopsis argyrophylla leaves had activity against C. glabrata (MIC 2.83 µg/mL) and ethanolic extract obtained from Caryocar coriaceum bark and fruit pulp exhibited MIC of 4.1 µg/mL on Microsporum canis. For bacteria, compounds isolated from the dichloromethane extract of Peritassa campestris, lectin extracted from a saline extract of Portulaca elatior and essential oils of Myrciaria pilosa exhibited significant effect against Bacillus megaterium (MIC 0.78 µg/mL), Pseudomonas aeruginosa (MIC 4.06 µg/mL) and Staphylococcus aureus strains (MIC 5.0 µg/mL), respectively. The findings support the antimicrobial and bioeconomic potential of plants from Brazilian biodiversity and their promising health applications.

Response surface methodology (RSM) to evaluate both the extraction of triterpenes and sterols from jackfruit seed with supercritical CO2 and the biological activity of the extracts

Jackfruit seeds are an underestimate residue having important biological activity such as anti-inflammatory, cytotoxicity and antimicrobial effects. However few researches have been done for this material using alternative extraction technologies, so this study aimed to evaluate the extraction of triterpenes and sterols from jackfruit seed by applying high- and low-pressure techniques. Response surface methodology (RSM) was used to determine the best conditions of pressure, temperature and CO2 flow rate for extraction with supercritical CO2. The yield and profile of these compounds were compared with the low pressure technique, which was considered as a reference. In vitro biological tests of anti-inflammatory activity and cytotoxicity in L929 and RAW 264.7 cells were also performed. The best extraction conditions in SFE for sterols were 40 °C/20 MPa/4 mL min-1 (0.832 ± 0.007 mgSR g-1 sample) and 40 °C/20 MPa/3 mL min-1 (0.800 ± 0.009 mgSR g-1 sample), for triterpenes were 50 °C/12 MPa/4 mL min-1 (1.501 ± 0.004 mgTT g-1 sample) and 45 °C/9.3 MPa/3.5 mL min-1 (1.485 ± 0.004 mgTT g-1 sample). No cytotoxic activity was detected in L929 cells in the extracts obtained from ethanol up to concentration of 100 μg mL-1 of extract. The Pearson's coefficient indicated that the reduction in cell viability was related to the concentration of triterpenes. Anti-inflammatory assays showed that some extracts could inhibit the inflammatory action induced in RAW 264.7 cells at concentration of 30 μg mL-1 of extract. Our results justify the further exploration of these characteristics to obtain natural products for the pharmaceutical and food industries.

Valorization of byproducts from tropical fruits: A review, Part 2: Applications, economic, and environmental aspects of biorefinery via supercritical fluid extraction

The global trade of tropical fruits is expected to increase significantly in the coming years. In 2018, the production was approximately 100 million tones, an increase of 3.3% compared to the previous year. Nevertheless, according to the Food and Agricultural Organization, every year one-third of the food produced in the world for human consumption is lost or wasted. More specifically, around 45% of the fruits, constituted mainly by peels, seeds, and pulps after juice extraction, are discarded mainly in the agricultural and processing steps. Therefore, decreasing and/or using these byproducts, which are often rich in bioactive components, have become an important focus for both the scientific community and the fruit processing industry. In this line, supercritical fluid extraction (SFE) technology is expected to play a significant role in the valorization of these byproducts. This review presents the concepts of a tropical fruit biorefinery using supercritical CO₂ extraction and the potential applications of the isolated fractions. There is a specific focus on the extraction of bioactive compounds, that is, carotenoids and phenolics, but also oils and other valuable molecules. Moreover, the techno-economic and environmental performance is assessed. Overall, the biorefinery of tropical fruits via SFE provides new opportunities for development of food and pharmaceutical products with improved economic and environmental performance.