This tutorial review aims at providing a complete overview of the strategies for the conversion of lignocellulose in current and future biorefineries, with a particular focus on the transformation of lignin toward valuable products.

The stone of Cornus mas L. remains the least known morphological part of this plant, whereas the fruit is appreciated for both consumption purposes and biological activity. The stone is considered to be a byproduct of fruit processing and very little is known about its phytochemical composition and biological properties. In this study, the complete qualitative determination of hydrolyzable tannins, their quantitative analysis, total polyphenolic content, and antioxidant properties of the stone of C. mas are presented for the first time. The 37 identified compounds included the following: various gallotannins (11), monomeric ellagitannins (7), dimeric ellagitannins (10), and trimeric ellagitannins (7). The presence of free gallic acid and ellagic acid was also reported. Our results demonstrate that C. mas stone is a source of various bioactive hydrolyzable tannins and shows high antioxidant activity which could allow potential utilization of this raw material for recovery of valuable pharmaceutical or nutraceutical substances. The principal novelty of our findings is that hydrolyzable tannins, unlike other polyphenols, have been earlier omitted in the evaluation of the biological activities of C. mas. Additionally, the potential recovery of these bioactive chemicals from the byproduct is in line with the ideas of green chemistry and sustainable production.

Residual banana bulbs (RBB) were characterized and assessed as a potential starch and cellulose-based feedstock for bioethanol production. To facilitate the enzymatic digestibility, hydrothermal pretreatment was performed on RBB prior to simultaneous saccharification and fermentation (SSF) with Saccharomyces cerevisiae. Composition of RBB was similar to traditional starch and cellulose-based feedstocks with high glucan (60 g/100 gDM) and relatively low lignin content (7 g/100 gDM). Both amylase and cellulase were needed to efficiently hydrolyze RBB. The highest ethanol yield (310 kg EtOH/ton_DM_RBB, 93% of theoretical production based on total available glucose) was obtained with non-pretreated RBB. SSF can be carried out at lower RBB concentrations. Hydrothermal pretreatment affected negatively the bioethanol potential due to the loss of fermentable carbohydrates. In a case study of an African leading producer of bananas and plantains (Cameroon), the energy derived from bioethanol was 80 GWh ethanol/year and corresponded to 1.6% of the annual transportation requirement. This study shows that RBB is a promising alternative feedstock for bioethanol production.

Polycystic ovarian syndrome (PCOS) is one of the most common heterogeneous endocrine and metabolic disorders in premenopausal women. It is a complex multifactorial disorder with strong epigenetic and environmental influences, including factors related to eating habits and lifestyle. There is a close relationship between obesity and PCOS. Weight gain and obesity are often clinical symptoms manifested by biochemical markers. Moreover, abdominal obesity in women with PCOS is involved in the development of inflammatory changes. A significant share of balanced therapies correcting the lifestyle of patients is suggested, e.g., with the implementation of appropriate diets to minimize exposure to inflammatory factors and prevent abnormal immune system stimulation. In the case of obese patients with PCOS, planning a diet program and supporting the motivation to change eating habits play an important role to lose weight and lower BMI. Probiotics/synbiotic supplementation may enhance weight loss during the diet program and additionally positively affect metabolic and inflammatory factors by improving the intestinal microbiome.

Abiotic stress conditions, such as salinity, affect plant development and productivity and threaten the sustainability of agricultural production. Salt has been proven to accumulate in soil and water over time as a result of various anthropogenic activities and climatic changes. Species of the genus Salicornia thrive in the most saline environments and have a wide climatic tolerance. They can be found in a variety of subtropical, oceanic, and continental environments. This study aims to establish Salicornia europaea as a novel source of plant-based compounds that can grow in areas unsuitable for other crops. The morphological and compositional changes in the tissues of S. europaea in different consecutive developmental stages have not been investigated so far. Therefore, a comprehensive study of changes during the lifecycle of S. europaea was carried out, following changes in the plant’s composition, including biomass yield, and soluble and insoluble compounds. For this, plants were cultivated in hydroponics for 15 weeks and harvested weekly to analyze biomass production, to determine soluble and insoluble compounds, protein content, and polyphenols. According to the results, glucan, xylan, and lignin increase with plant age, while water extractives decrease. Protein content is higher in young plants, while flavonoid content depends on the phenological stage, decreasing in the early flowering stage and then increasing as plants enter early senescence. Our results can aid in finding the optimal harvesting stage of S. europaea, depending on the component of interest.

Three types of phenolic acids (caffeic, ferulic, and chlorogenic acid) were identified and quantified in two halophytic plants (Salicornia bigelovii and Salicornia sinus-persica). Analysis was performed using a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) system via the standard addition method. The matrix effect (ME), recovery efficiency (RE), and process efficiency (PE) parameters were evaluated for S. bigelovii extracts, which revealed a strong ME on the ionization of the three acids. The matrix had little to no effect on the extraction step for all samples. The quantitation results revealed that S. bigelovii was more abundant in the acids analyzed (total of 319.2 µg/g dry water extract) when compared to S. sinus-persica (117.2 µg/g dry water extract), and chlorogenic acid was the dominant component. The extractives content was high in both plants, representing over 35% of the dry plant weight. All the extracts exhibited antioxidant activity toward both DPPH and ABTS radicals at levels comparable to other medicinal plants.