STONE TOOL FUNCTIONS, HOUSEHOLD ACTIVITIES, AND FORMATIVE LITHIC ECONOMIES IN NORTHERN TLAXCALA, MEXICO

High-magnification use-wear analyses create datasets that enable microeconomic studies of lithic consumption and household activities that complement macroeconomic studies of lithic production and exchange to collectively improve our reconstructions of ancient economies. In recent decades, compositional and technological analyses have revealed how certain obsidian sources and lithic technologies were exploited, produced, and exchanged in Mexico's central highlands region during the Formative period (1500 b.c.–a.d. 100). This article presents use-wear analyses of 275 lithic artifacts from four sites in northern Tlaxcala—Amomoloc (900–650 b.c.), Tetel (750–500 b.c.), Las Mesitas (600–500 b.c.), and La Laguna (600–400 b.c. and 100 b.c.–a.d. 150)—to compare household activities with lithic technologies and evaluate their roles in regional economies. Blades were used for subsistence and domestic crafting; maguey fiber extraction for textile production increased over time, especially in non-elite households. The preparation and consumption of meat acquired by hunting and other methods increased slightly over time, and bipolar tools were used as kitchen utensils. Bloodletting was practiced with two variations of late-series pressure blades, but these and other tools were neither exchanged as nor used to craft prestige goods, often viewed as driving forces of Formative economies in Mesoamerica.

Oligosaccharides production by enzymatic hydrolysis of banana pseudostem pulp

Banana production generates significant amounts of agricultural wastes, being fiber extraction one of the most relevant alternatives for their valorization. This process produces banana’s pseudostem pulp (BPP) as a byproduct, which shows an interesting composition for the biorefinery’s biochemical platform, with high polysaccharides (68%) and low lignin contents. This work deals with the enzymatic hydrolysis (EH) of raw and hydrothermally pre-treated BPP, focusing on the production of oligosaccharides (OS). Raw BPP hydrolysis with cellulase at different dosages rendered only 3.2% OS yields (OSY). Pectinase addition has not affected EH performance. On the other hand, EH of hydrothermally pre-treated BPP at 150 °C and 170 °C (P150 and P170) allowed to increase OSY up to 28% (P150, 1 FPU of cellulase/g dry biomass, 12 h), being 72% of the solubilized sugars in the form of cello-oligosaccharides. This last condition was subjected to a multi-stage EH strategy without improvements in OSY. An endo-glucanase was also tested, but obtained OSY were lower than cellulase results. Finally, obtained OS demonstrated to stimulate the growth of two Lactobacilli strains. The results show that BPP pre-treated under mild operational conditions is a good candidate for cello-oligosaccharides production by EH using 1 FPU/g DB of cellulase with a simple strategy. Graphical abstract

OPTIMIZATION OF RETTING AND EXTRACTION THROUGH CONSTITUTIVE MATERIAL MODELLING OF PLANT STEMS FOR VARIABILITY REDUCTION IN EXTRACTED NATURAL FIBERS

Natural plant fibers compared to glass fibers can provide a cost effective, lightweight and carbon negative reinforcement for polymer composites. However, the current commercial fiber extraction process induces defects including middle lamellae weakening during retting and kink bands during mechanical working. This leads to high variability in mechanical properties, making these fibers less favorable for structural applications at industrial scale. The aim of current research is to reduce this variability by studying the underlying mechanisms of natural fiber extraction to minimize fiber damage occurring at various steps in the process. In this study, flax stems were retted using the conventional dew/field and lab scale controlled enzymatic retting. The hand decorticated fibers from both methods were compared and enzymatic retting showed promising results in producing fine and uniform fibers as compared to fibers extracted by dew retting. To establish the constitutive parameters of the fibers for Finite Element Modeling (FEM), single retted flax stems were compression tested using a Texture Analyzer. This data can serve as the basis for modeling the mechanical deformation of plant stems passing through breaking rollers which is the first step in extraction after retting. The goal is to optimize the roller design and process conditions required to extract fibers with minimal damage and variability.

The Sisal Virome: Uncovering the Viral Diversity of Agave Varieties Reveals New and Organ-Specific Viruses

Sisal is a common name for different plant varieties in the genus Agave (especially Agave sisalana) used for high-quality natural leaf fiber extraction. Despite the economic value of these plants, we still lack information about the diversity of viruses (virome) in non-tequilana species from the genus Agave. In this work, by associating RNA and DNA deep sequencing we were able to identify 25 putative viral species infecting A. sisalana, A. fourcroydes, and Agave hybrid 11648, including one strain of Cowpea Mild Mottle Virus (CPMMV) and 24 elements likely representing new viruses. Phylogenetic analysis indicated they belong to at least six viral families: Alphaflexiviridae, Betaflexiviridae, Botourmiaviridae, Closteroviridae, Partitiviridae, Virgaviridae, and three distinct unclassified groups. We observed higher viral taxa richness in roots when compared to leaves and stems. Furthermore, leaves and stems are very similar diversity-wise, with a lower number of taxa and dominance of a single viral species. Finally, approximately 50% of the identified viruses were found in all Agave organs investigated, which suggests that they likely produce a systemic infection. This is the first metatranscriptomics study focused on viral identification in species from the genus Agave. Despite having analyzed symptomless individuals, we identified several viruses supposedly infecting Agave species, including organ-specific and systemic species. Surprisingly, some of these putative viruses are probably infecting microorganisms composing the plant microbiota. Altogether, our results reinforce the importance of unbiased strategies for the identification and monitoring of viruses in plant species, including those with asymptomatic phenotypes.

Extraction of cellulose fibers from flax and hemp: a review

The paper is a review on the extraction processes of cellulosic fibers from flax and hemp. The two lignocellulosic crops have a long history of use by humans for extraction of the bast fibers among other purposes. The utility of bast fibers declined over time with industrial advances and changes to the economy, but of late, with an increase of focus on environmental impact and sustainability, there is a renewed interest in these resources. The use of biomass-based resource requires an appreciation of plant anatomy and the agronomical variables in their cultivation and harvesting. This review provides an overview of these aspects as well as of the processes of retting for initial weakening of the plant structure in preparation for fiber extraction, degumming to isolate fiber bundles, and delignification.

Design, Development, and Performance Evaluation of a Power-Operated Jute Fiber Extraction Machine

Jute is the golden fiber of Bangladesh, but its production is declining due to the involvement of higher production and processing costs, where a major portion of the cost is needed for fiber extraction. Labor unavailability and increasing labor cost have led to higher jute fiber production cost. To address these issues, this study looks at the development of a power-operated and cost-effective fiber extraction machine aiming at reducing the production cost. The study was conducted at the Rangpur regional office premises of Practical Action in Bangladesh, and the developed machine was branded as “Aashkol”, which had the following major parts: a feeding tray, a primary extraction roller, a secondary extraction roller, grabbing rollers, fiber collection stand, base frame, protection cover, and a spring-loaded tray under the primary extraction roller. The Aashkol can extract green ribbon from the jute stem, but jute sticks were broken down into smaller pieces (3–6 cm). The performance evaluation of the machine was conducted using different types of jute (Deshi, Kenaf, and Tossa) and compared with another jute extraction machine (KP model, introduced by Karupannya Rangpur Ltd.). The Aashkol-based extraction and improved retting systems were also evaluated and compared with traditional jute extraction systems. The jute stem input capacity (4.99 t h−1) of the Aashkol was 47.6% higher than the KP model (3.38 t h−1). Compared with the traditional system, across jute types, the Aashkol produced a 9% higher fiber yield and saved 46% retting time. Overall, the Aashkol reduced 90% of the labor requirement and saved 11.6 USD t−1 in jute fiber extraction and retting than the traditional method.

Research on the Physical Characteristic Parameters of Banana Bunches for the Design and Development of Postharvesting Machinery and Equipment

In the operations of the banana postharvesting process, the design and development related to the dehanding machine, the cutting and crushing machine of bunch stalks, and the fiber extraction machine of bunch stalks are in the initial stages. In addition, with the development of society and urbanization, the aging populations in hilly and mountainous areas, where bananas are planted, are becoming a more and more serious problem. The basic physical characteristic parameters of banana bunches, banana hands, and bunch stalks are the basis for studying their biomechanical properties and designing and developing the corresponding mechanical equipment. We measured the diameter, thickness of rind, curvature, density, moisture content, diameter of vascular bundle, weight of bunch stalk, and axial distance and circumferential angle of Brazilian and plantain banana hands using experiments and statistical analysis. Through the combination of physical experiments and numerical statistics, we obtained the value range and changing law of the physical characteristic parameters of banana bunches.

The Potential of Grape Pomace Varieties as a Dietary Source of Pectic Substances

Grape pomace is one of the most abundant solid by-products generated during winemaking. A lot of products, such as ethanol, tartrates, citric acid, grape seed oil, hydrocolloids, bioactive compounds and dietary fiber are recovered from grape pomace. Grape pomace represents a major interest in the field of fiber extraction, especially pectin, as an alternative source to conventional ones, such as apple pomace and citrus peels, from which pectin is obtained by acid extraction and precipitation using alcohols. Understanding the structural and functional components of grape pomace will significantly aid in developing efficient extraction of pectin from unconventional sources. In recent years, natural biodegradable polymers, like pectin has invoked a big interest due to versatile properties and diverse applications in food industry and other fields. Thus, pectin extraction from grape pomace could afford a new reason for the decrease of environmental pollution and waste generation. This paper briefly describes the structure and composition of grape pomace of different varieties for the utilization of grape pomace as a source of pectin in food industry.