Value-Added Metabolites from Agricultural Waste and Application of Green Extraction Techniques

Agricultural biomass/waste-based materials could be a potential adsorption-type remediation contributor to environmental pollution induced by pesticides-A critical review

The widespread use of pesticides that are inevitable to keep the production of food grains brings serious environmental pollution problems. Turning agricultural biomass/wastes into materials addressing the issues of pesticide contaminants is a feasible strategy to realize the reuse of wastes. Several works summarized the current applications of agricultural biomass/waste materials in the remediation of environmental pollutants. However, few studies systematically take the pesticides as an unitary target pollutant. This critical review comprehensively described the remediation effects of crop-derived waste (cereal crops, cash crops) and animal-derived waste materials on pesticide pollution. Adsorption is considered a superior and highlighted effect between pesticides and materials. The review generalized the sources, preparation, characterization, condition optimization, removal efficiency and influencing factors analysis of agricultural biomass/waste materials. Our work mainly emphasized the promising results in lab experiments, which helps to clarify the current application status of these materials in the field of pesticide remediation. In the meantime, rigorous pros and cons of the materials guide to understand the research trends more comprehensively. Overall, we hope to achieve a large-scale use of agricultural biomass/wastes.

Potato Berries as a Valuable Source of Compounds Potentially Applicable in Crop Protection and Pharmaceutical Sectors: A Review

Potato (Solanum tuberosum) is a major agricultural crop cultivated worldwide. To meet market demand, breeding programs focus on enhancing important agricultural traits such as disease resistance and improvement of tuber palatability. However, while potato tubers get a lot of attention from research, potato berries are mostly overlooked due to their level of toxicity and lack of usefulness for the food production sector. Generally, they remain unused in the production fields after harvesting the tuber. These berries are toxic due to high levels of glycoalkaloids, which might confer some interesting bioactivities. Berries of various solanaceous species contain bioactive secondary metabolites, suggesting that potato berries might contain similarly valuable metabolites. Therefore, possible applications of potato berries, e.g., in the protection of plants against pests and pathogens, as well as the medical exploitation of their anti-inflammatory, anticarcinogenic, and antifungal properties, are plausible. The presence of valuable compounds in potato berries could also contribute to the bioeconomy by providing a novel use for otherwise discarded agricultural side streams. Here we review the potential use of these berries for the extraction of compounds that can be exploited to produce pharmaceuticals and plant protection products.

Pressurized liquid extraction of glucosinolates from Camelina sativa (L.) Crantz by-products: Process optimization and biological activities of green extract

The cultivation of Camelina sativa (L.) Crantz is rapidly increasing due to oil production resulting in a substantial volume of by-products, which still have an interesting composition in secondary metabolites, especially glucosinolates. Therefore, a green extraction procedure of glucosinolates by Pressurised Liquid Extraction was developed and optimized using a chemometric approach. Furthermore, the glucosinolates were purified by solid phase extraction, and a preliminary study on bioaccessibility and bioavailability study was carried out to evaluate the resistance of the glucosinolates to the digestive process. The application of pressurised liquid extraction to the recovery of glucosinolates from camelina sativa by-product, is a green, automatic, and rapid method, representing a valid alternative to conventional extraction method to obtain ingredients for food industries.

Resource-Efficient Use of Residues from Medicinal and Aromatic Plants for Production of Secondary Plant Metabolites

Although people's interest in green and healthy plant-based products and natural active ingredients in the cosmetic, pharmaceutical, and food industries is steadily increasing, medicinal and aromatic plants (MAPs) represent a niche crop type.It is possible to increase cultivation and sales of MAPs, by utilizing plant components that are usually discarded. This chapter provides an overview of studies concerning material flows and methods used for sustainable production of valuable metabolites from MAPs between 2018 and 2023. Additionally, it describes new developments and strategies for extraction and isolation, as well as innovative applications. In order to use these valuable resources almost completely, a systematic recycling of the plant material is recommended. This would be a profitable way to increase sustainability in the cultivation and usage of MAPs and provide new opportunities for extraction in plant science.

Emerging trends in the appliance of ultrasonic technology for valorization of agricultural residue into versatile products

The utilization of agricultural residues to obtain biocompounds of high-added value has significantly increased in the past decades. The conversion of agro-based residues into valuable products appears to be an economically efficient, environment-friendly, and protracted waste management practice. The implementation of ultrasonic technologies in the conversion of value-added goods from agricultural waste materials through pre-treatment and valorization processes has imparted many advantageous effects including rapid processing, effective process performance, minimization of processing steps, minimal dependency on harmful chemicals, and an increased yield and properties of bio-products. To further enliven the literature and inspire new research investigations, this review covers the comprehensive work including theoretical principles, processes, and potential benefits of ultrasonic treatment technologies to assist the production of bio-products which emphasize the extraction yield and the characteristic of the end-product extracted from agriculture residues. A detailed evaluation of these methods and key aspects impacting their performance as well as the features and shortcomings of each ultrasound-assisted approach is also discussed. This review also addressed some of the challenges associated with using ultrasonic irradiation and proposed several potential techniques to maximize productivity. Understanding the concept of ultrasonication technique allow the academician and industrial practitioners to explore the possibility of applying a greener and sustainable approach of biomass extraction to be translated into higher scale production of commercial products.

A residue management machine for chopping paddy residues in combine harvested paddy field

Nowadays, Combine Harvesters are the most commonly used device for harvesting crops; as a result, a large amount of plant material and crop residue is concentrated into a narrow band of plant material that exits the combine, challenging the residue management task. This paper aims to develop a crop residue management machine that can chop paddy residues and mix them with the soil of the combined harvested paddy field. For this purpose, two important units are attached to the developed machine: the chopping and incorporation units. The tractor operates this machine as the main source, with a power range of about 55.95 kW. The four independent parameters selected for the study were rotary speed (R₁ = 900 & R₂ = 1100 rpm), forward speed (F₁ = 2.1 & F₂ = 3.0 Kmph), horizontal adjustment (H₁ = 550 & H₂ = 650 mm), and vertical adjustment (V₁ = 100 & V₂ = 200 mm) between the straw chopper shaft and rotavator shaft and its effect was found on incorporation efficiency, shredding efficiency, and trash size reduction of chopped paddy residues. The incorporation of residue and shredding efficiency was highest at V₁H₂F₁R₂ (95.31%) and V₁H₂F₁R₂ (61.92%) arrangements. The trash reduction of chopped paddy residue was recorded maximum at V₁H₂F₂R₂ (40.58%). Therefore, this study concludes that the developed residue management machine with some modifications in power transmission can be suggested to the farmers to overcome the paddy residue issue in combined harvested paddy fields.

Temporal variations in soil aggregation following olive pomace and vineyard pruning waste compost applications on clay, loam, and sandy loam soils

This study was aimed to determine the temporal effects of olive pomace (OPC) and vineyard pruning waste (VPC) composts on soil aggregation of three different textured soils. Both OPC and VPC are the most common agricultural wastes in the Mediterranean Region. The application of these composts to soils with different textures (clay, loam, and sandy loam) at different rates and knowing how long after the application the aggregate stability (AS) reaches the maximum (for different compost, texture, and rate) increases the novelty value of this study. Composts were prepared in automatic temperature and aeration-controlled reactors. The experiment consisted of three different soil textures (clay, loam, and sandy loam), five different treatments (control, 3% and 6% OPC, 3% and 6% VPC), 10 different incubation times, and four replications. The highest AS values were obtained with 6% VPC application on the 210th day of incubation for clay and loam soils while it was the highest for 6%OPC on the 120th day of incubation for sandy loam soil. Soil carbon (TC) was the strongest and positively correlated with AS 90 days after VPC and OPC applications in all soils. Final TC stocks increased by 131% and 417% in clay, 72% and 251% in loam, and 21 to 257% in sandy loam soil, compared to 15 days of incubation. OPC and VPC amendments to clay, loam, and sandy loam soils increased AS while reducing the mean weight diameter (MWD) of aggregates. It took a shorter time (90 days) for the VPC application to increase the amount of TC in soils.

The Use of Baikal Psychrophilic Actinobacteria for Synthesis of Biologically Active Natural Products from Sawdust Waste

One of the relevant areas in microbiology and biotechnology is the study of microorganisms that induce the destruction of different materials, buildings, and machines and lead to negative effects. At the same time, the positive ecological effects of degradation can be explained by the detoxication of industrial and agricultural wastes, chemical substances, petroleum products, xenobiotics, pesticides, and other chemical pollutants. Many of these industrial wastes include hard-to-degrade components, such as lignocellulose or plastics. The biosynthesis of natural products based on the transformation of lignocellulosic wastes is of particular interest. One of the world’s unique ecosystems is presented by Lake Baikal. This ecosystem is characterized by the highest level of biodiversity, low temperatures, and a high purity of the water. Here, we studied the ability of several psychrophilic representatives of Baikal Actinobacteria to grow on sawdust wastes and transform them into bioactive natural products. Different strains of both widely spread genus of Actinobacteria and rare genera of Actinobacteria were tested. We used the LC-MS methods to show that Actinobacteria living in sawmill wastes can produce both known and novel natural products with antibiotic activity. We demonstrated that the type of sawmill wastes and their concentration influence the Actinobacteria biosynthetic potential. We have shown for the first time that the use of Baikal psychrophilic microorganisms as a factory for biodegradation is applicable for the transformation of lignocellulosic wastes. Thus, the development of techniques for screening novel natural products leads to an elaboration on the active ingredients for novel drugs.

White Grape Pomace Valorization for Remediating Purposes

The present investigation focuses on a possible alternative to reduce grape pomace’s negative impact on the environment by exploiting its capacities for wastewater remediation. Therefore, three directions are followed: (1) the characterization of white grape byproducts’ antioxidant and antiradical properties; (2) the determination of organophosphorus compound concentration that might be present in the samples; and (3) the evaluation of the possible use for wastewater remediation. The grape pomace was used for obtaining different extracts considering different extraction conditions. The hydroalcoholic extracts have an increased amount of total phenolic content. The lyophilized hydroalcoholic extract showed high total phenolic content (159.52 mg/100 g) and low organophosphorus content (0.257 ± 0.015 nmol). The lowest DPPH antiradical-scavenging activities were obtained for the extracts in ethanol obtained from refrigerated pomace (0.055) and for dried pomace (0.045).

Polysaccharides in Agro-Industrial Biomass Residues

The large-scale industrial use of polysaccharides to obtain energy is one of the most discussed subjects in science. However, modern concepts of biorefinery have promoted the diversification of the use of these polymers in several bioproducts incorporating concepts of sustainability and the circular economy. This work summarizes the major sources of agro-industrial residues, physico-chemical properties, and recent application trends of cellulose, chitin, hyaluronic acid, inulin, and pectin. These macromolecules were selected due to their industrial importance and valuable functional and biological applications that have aroused market interests, such as for the production of medicines, cosmetics, and sustainable packaging. Estimations of global industrial residue production based on major crop data from the United States Department of Agriculture were performed for cellulose content from maize, rice, and wheat, showing that these residues may contain up to 18%, 44%, and 35% of cellulose and 45%, 22%, and 22% of hemicellulose, respectively. The United States (~32%), China (~20%), and the European Union (~18%) are the main countries producing cellulose and hemicellulose-rich residues from maize, rice, and wheat crops, respectively. Pectin and inulin are commonly obtained from fruit (~30%) and vegetable (~28%) residues, while chitin and hyaluronic acid are primarily found in animal waste, e.g., seafood (~3%) and poultry (~4%).