A Two-step Strategy for High-Value-Added Utilization of Rapeseed Meal by Concurrent Improvement of Phenolic Extraction and Protein Conversion for Microbial Iturin A Production

Rapeseed meal (RSM) is a major by-product of oil extraction from rapeseed, consists mainly of proteins and phenolic compounds. The use of RSM as protein feedstock for microbial fermentation is always hampered by phenolic compounds, which have antioxidant property with health-promoting benefits but inhibit bacterial growth. However, there is still not any good process that simultaneously improve extraction efficiency of phenolic compounds with conversion efficiency of protein residue into microbial production. Here we established a two-step strategy including fungal pretreatment followed by extraction of phenolic compounds. This could not only increase extraction efficiency and antioxidant property of phenolic compounds by about 2-fold, but also improve conversion efficiency of protein residue into iturin A production by Bacillus amyloliquefaciens CX-20 by about 33%. The antioxidant and antibacterial activities of phenolic extracts were influenced by both total phenolic content and profile, while microbial feedstock value of residue was greatly improved because protein content was increased by ∼5% and phenolic content was decreased by ∼60%. Moreover, this two-step process resulted in isolating more proteins from RSM, bringing iturin A production to 1.95 g/L. In conclusion, high-value-added and graded utilization of phenolic extract and protein residue from RSM with zero waste is realized by a two-step strategy, which combines both benefits of fungal pretreatment and phenolic extraction procedures.

Phenolic Compounds in Tea: Phytochemical, Biological, and Therapeutic Applications

Phenolic compounds are one of the major and most complex groups of phytochemicals found among plant kingdom. Structurally they comprise of aromatic ring along with one or more hydroxyl groups. Based on the structure they are divided into subgroups such as phenolic acids, flavonoids, tannins, coumarins, lignans, quinones, stilbenes and carotenoids. Plant polyphenols are gaining popularity as a result of their potent antioxidant properties and notable effects in the prevention of oxidative stress-related diseases. Extraction, identification and characterisation of phenolic compounds from various plant sources has become a major area of health and medical research in the recent years. The major bioactive compounds responsible for tea’s health benefits are thought to be phenolics. Catechin derivatives make up the majority of the phenolic compounds found in tea, and though flavonols and phenolic acids are also present in smaller amounts. The bioactivity of the compounds has been linked to a lower risk of serious illnesses like cancer, cardiovascular disease, and neurodegenerative disease. This chapter covers phenolic extraction, purification, analysis and quantification, as well as their antioxidant properties in different varieties of tea leaves.

OPTIMIZATION OF PHENOLIC COMPOUNDS EXTRACTION FROM PURPLE BASIL LEAF BY CONVENTIONAL AND MICROWAVE ASSISTED EXTRACTION METHOD

The present study aimed to determine the optimum extraction conditions of conventional solvent extraction (CSE) and microwave-assisted extraction (MAE) techniques to obtain maximum total phenolic (TPC), total flavonoid (TFC), total anthocyanin (TAC) and antioxidant capacity (AA). Response surface methodology (RSM) and central composite design (CCD) were used to determine optimum points of CSE and MAE. Both two extraction methods, all parameters significantly affected TPC, AA, TFC and TAC (p<0.05). MAE showed higher bioactive compounds yield than that of CSE. Optimum point for CSE and MAE was found to be 60°C and 30 min and 591.83 W and 2.98 min respectively. TPC, AA, TFC and TAC were obtained as 33.81mg/g, 160.27 mg/g, 11.89 mg/g and 331.01 mg/kg for CSE and 62.99 mg/g, 214.62 mg/g, 21.80 mg/g and 3462.93 mg/kg for MAE respectively. This study recommended that the MAE should be used for the extraction of PBL to increase phenolic extraction yield.

Latest Insights on Novel Deep Eutectic Solvents (DES) for Sustainable Extraction of Phenolic Compounds from Natural Sources

Phenolic compounds have long been of great importance in the pharmaceutical, food, and cosmetic industries. Unfortunately, conventional extraction procedures have a high cost and are time consuming, and the solvents used can represent a safety risk for operators, consumers, and the environment. Deep eutectic solvents (DESs) are green alternatives for extraction processes, given their low or non-toxicity, biodegradability, and reusability. This review discusses the latest research (in the last two years) employing DESs for phenolic extraction, solvent components, extraction yields, extraction method characteristics, and reviewing the phenolic sources (natural products, by-products, wastes, etc.). This work also analyzes and discusses the most relevant DES-based studies for phenolic extraction from natural sources, their extraction strategies using DESs, their molecular mechanisms, and potential applications.

Optimization of methodology for the extraction of polyphenolic compounds with antioxidant potential and α-glucosidase inhibitory activity from Jamun (Syzygium cumini L.) seeds

Jamun (Syzygium cumini L.) seed is one of the rich sources of polyphenolic compounds​ ​with antioxidant potential and α-glucosidase inhibitory activity. A study was conducted to​ ​optimize the methodology for the extraction of polyphenolic compounds (total phenolic​ ​and flavonoid contents) with antioxidant potential and α-glucosidase inhibitory activity​ ​from Jamun seed powder. The study showed that the nature of solvent and extraction​ ​conditions had a significant effect on total phenolic content (TPC), total flavonoid content​ ​(TFC), antioxidant potential, and α-glucosidase inhibitory activity. The TPC varied between​ ​6.0 (mg/g Jamun seed powder) for the acetone extract to 119.2 (mg/g) for 80% aqueous​ ​acetone extract and TFC varied between 1.06 mg/g for the acetone to 10.81 mg/g for the​ ​80% aqueous methanol. From the study, it was apparent that an aqueous form of acetone​ ​(acetone: water 80:20, v/v) is a better solvent system for extraction of polyphenolic​ ​compounds with high antioxidant potential and α-glucosidase inhibitory activity.​ ​Ultrasonication for 60 min increased the efficiency of phenolic extraction.

Environmental Impact of Food Preparations Enriched with Phenolic Extracts from Olive Oil Mill Waste

Reducing food waste as well as converting waste products into second-life products are global challenges to promote the circular economy business model. In this context, the aim of this study is to quantify the environmental impact of lab-scale food preparations enriched with phenolic extracts from olive oil mill waste, i.e., wastewater and olive leaves. Technological (oxidation induction time) and nutritional (total phenols content) parameters were considered to assess the environmental performance based on benefits deriving by adding the extracts in vegan mayonnaise, salad dressing, biscuits, and gluten-free breadsticks. Phenolic extraction, encapsulation, and addiction to the four food preparations were analyzed, and the input and output processes were identified in order to apply the life cycle assessment to quantify the potential environmental impact of the system analyzed. Extraction and encapsulation processes characterized by low production yields, energy-intensive and complex operations, and the partial use of chemical reagents have a non-negligible environmental impact contribution on the food preparation, ranging from 0.71% to 73.51%. Considering technological and nutritional aspects, the extraction/encapsulation process contributions tend to cancel out. Impacts could be reduced approaching to a scale-up process.

PCR Development for the Diagnosis of Dermatophytes in Equines

Development and standardize of PCR for diagnose of most common equine dermatophytes was carried out. We used one reference strain and four isolates characterized by routinely methods from clinical samples. Sabouraud broth was used to obtain the fungal mass by long 8 days incubation. Once the mass was dried, it was pulverized with liquid nitrogen in a mortar and deposited in tubes to obtained DNA by phenolic extraction. NCBI GenBank data were used for the primer design, the sequences were aligned manually and once the initiators were selected, they were placed in the DNAMAN program, in order to differentiate the five species involved. We diagnosed successfully common dermatophytes in Equidae by standardized PCR test. A total of 50 samples were used for the challenge test, 22 have been declared positive by conventional diagnostic methods, and the remaining samples were selected randomly the obtained results were similar compared with conventional test. M. canis primers were highly sensitive. For the others species we need more samples to corroborate the usefulness of the test.