Bioactivities and Microbial Quality of Lycium Fruits (Goji) Extracts Derived by Various Solvents and Green Extraction Methods

Comparison of phenotypic and phytochemical profiles of 20 Lycium barbarum L. goji berry varieties during hot air-drying

The variety and drying stage of goji berries (GBs) may affect their final physical and chemical properties. This study investigated the differences in physical phenotypic parameters and major chemical composition parameters of 20 GBs varieties during four stages of hot air-drying (HD). The results indicated that the color difference values L*, a*, and b* decreased during the HD process. The contents of all amino acids decreased, with significant reductions in amino acids involved in the Maillard reaction. Correspondingly, the level of 5-hydroxymethylfurfural, a Maillard chemical reaction intermediates, increased. Furthermore, the decreased L* values were closely linked to the decomposition of carotenoids. Notably, the differences in constituents among different varieties of dried GBs were smaller than those in fresh GBs. These findings provide a theoretical basis for optimization of the GBs drying process, contributing to the expansion of GBs breeding programs and their use in global functional food and pharmaceutical industries.

Comprehensive evaluation on phenolic derivatives and antioxidant activities of diverse yellow maize varieties

The main phenolic derivatives and antioxidant capacity of ninety-three yellow maize varieties were investigated, together with their color parameters. Sixteen phenolics were identified in the free extract by UPLC-ESI-MS/MS, N', N″-diferuloyl putrescine and N', N″-dicoumaryl spermidine were the major phenolic derivatives. Fourteen phenolic compounds were found in the bound extract, with trans-p-coumaric acid, trans- and cis-ferulic acid being the predominant phenolic acids. The orange-yellow maize varieties presented the highest total phenolic content (TPC) and total flavonoid content (TFC), along with significantly higher antioxidant potential. Correlation analysis showed that b* value (corresponding to yellow degree) was positively correlated with the total carotenoid content (TCC), phenolic content, and antioxidant capacity (p < 0.05). Through Hierarchical Clustering Analysis (HCA), the 93 maize varieties could be divided into three categories according to b* value and antioxidant activity. The heatmap visualization further underscored the component differences across various varieties, unveiling the intricate phytochemical profiles of these maize varieties.

Microwave-Assisted Extraction of Secondary Metabolites Using Ethyl Lactate Green Solvent from Ambrosia arborescens: LC/ESI-MS/MS and Antioxidant Activity

Alternative solvents are being tested as green solvents to replace the traditional organic solvents used in both academy and industry. Some of these are already available, such as ethyl lactate, cyrene, limonene, glycerol, and others. This alternative explores eco-friendly processes for extracting secondary metabolites from nature, thus increasing the number of unconventional extraction methods with lower environmental impact over conventional methods. In this context, the Peruvian Ambrosia arborescens was our model while exploring a microwave-assisted extraction (MAE) approach over maceration. The objective of this study was to perform a phytochemical study including UHPLC-ESI-MS/MS and the antioxidant activity of Ambrosia arborescens, using sustainable strategies by mixing both microwaves and ethyl lactate as a green solvent. The results showed that ethyl lactate/MAE (15.07%) achieved a higher extraction yield than methanol/maceration (12.6%). In the case of the isolation of psilostachyin, it was similar to ethyl lactate (0.44%) when compared to methanol (0.40%). Regarding UHPLC-ESI-MS/MS studies, the results were similar. Twenty-eight compounds were identified in the ethyl lactate/MAE and methanol/maceration extracts, except for the tentative identification of two additional amino acids (peaks 4 and 6) in the MeOH extract. In relation to the antioxidant assay, the activity of the ethyl lactate extract was a little higher than the methanol extract in terms of ORAC (715.38 ± 3.2) and DPPH (263.04 ± 2.8). This study on A. arborescens demonstrated that the unconventional techniques, such as MAE related to ethyl lactate, could replace maceration/MeOH for the extraction and isolation of metabolites from diverse sources. This finding showed the potential of unconventional methods with green solvents to provide eco-friendly methods based on green chemistry.

Sustainable Green Extraction of Carotenoid Pigments: Innovative Technologies and Bio-Based Solvents

Carotenoids are ubiquitous and versatile isoprenoid compounds. The intake of foods rich in these pigments is often associated with health benefits, attributable to the provitamin A activity of some of them and different mechanisms. The importance of carotenoids and their derivatives for the production of foods and health-promotion through the diet is beyond doubt. In the new circular economy paradigm, the recovery of carotenoids in the biorefinery process is highly desirable, for which greener processes and solvents are being advocated for, considering the many studies being conducted at the laboratory scale. This review summarizes information on different extraction technologies (ultrasound, microwaves, pulsed electric fields, pressurized liquid extraction, sub- and supercritical fluid extraction, and enzyme-assisted extraction) and green solvents (ethyl lactate, 2-methyltetrahydrofuran, natural deep eutectic solvents, and ionic liquids), which are potential substitutes for more toxic and less environmentally friendly solvents. Additionally, it discusses the results of the latest studies on the sustainable green extraction of carotenoids. The conclusions drawn from the review indicate that while laboratory results are often promising, the scalability to real industrial scenarios poses a significant challenge. Furthermore, incorporating life cycle assessment analyses is crucial for a comprehensive evaluation of the sustainability of innovative extraction processes compared to industry-standard methods.

Microbial Diversity and Bioactive Compounds in Dried Lycium barbarum Fruits (Goji): A Comparative Study

This study compares the microbial diversity and content of bioactive compounds in dried goji berries available on the Polish market to those of the most highly valued goji berries from the Ningxia region in China. The content of phenols, flavonoids, and carotenoids were determined, as well as the antioxidant capacities of the fruits. The quantitative and qualitative composition of the microbiota inhabiting the fruits was assessed using metagenomics by high-throughput sequencing on the Illumina platform. The highest quality was demonstrated by naturally dried fruits from the Ningxia region. These berries were characterized by a high content of polyphenols and high antioxidant activity, as well as high microbial quality. The lowest antioxidant capacity was shown by goji berries cultivated in Poland. However, they contained a high amount of carotenoids. The highest microbial contamination was found in the goji berries available in Poland (>10⁶ CFU/g), which is important in terms of consumer safety. Despite the widely accepted benefits of consuming goji berries, both the country of cultivation and the preservation method may influence their composition, bioactivity, and microbial quality.