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1.
Carbohydr Polym ; 341: 122347, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-38876717

ABSTRACT

While the extensive utilization of disposable plastic straws has resulted in significant environmental issues such as microplastics and soil and ocean pollution, the quest for alternative straws for versatile use remains a formidable challenge. Here, drawing inspiration from naturally water-resistant materials such as bones and sea urchins, we have developed seaweed-based straws with significantly improved water resistance and mechanical strength via in-situ mineralization of CaCO3 on their surfaces. Specifically, the COO- groups on the G (α-L-guluronate) blocks of alginate were employed to establish a robust cross-linked network, while the COO- groups on the M (ß-D-mannuronate) blocks attracted free Ca2+ through electrostatic forces, thereby promoting CaCO3 nucleation. This effectively prevents COOH groups from hydrating, reducing swelling, and results in the fabrication of nano- to micron-sized CaCO3 particles that reinforce the structure without compromising the cross-linked network. Compared with the control group, the S5% sample (prepared with 5 % Na2CO3 solution) exhibited a 102 % increase in water contact angle, a 35 % decrease in swelling degree, and a 35.5 % and 37.5 % increase in ultimate flexural and tensile stress, respectively. Furthermore, the potential use of these straws as a waste for heavy metal adsorption was investigated, addressing environmental concerns while demonstrating economic feasibility.


Subject(s)
Calcium Carbonate , Seaweed , Calcium Carbonate/chemistry , Seaweed/chemistry , Tensile Strength , Alginates/chemistry , Surface Properties , Water/chemistry
2.
Carbohydr Polym ; 334: 122027, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38553226

ABSTRACT

To investigate the effect of oil additives on improving the water resistance of corn starch straws, corn oil (CO), soybean oil (SO), rapeseed oil (RO), peanut oil (PO), lard (LD) and coconut oil (CCO) were chosen and compared the structure and properties of starch straws with different oil additives. Corn starch straws (CS), and starch straws supplemented with CO, SO, RO, PO, LD and CCO were prepared by thermoplastic extrusion. The results showed that the incorporation of oils effectively enhanced the water resistance of starch straws such as water absorption, water solubility and water swelling performance. Meanwhile, the flexural strength of starch straws significantly increased. There was no significant linear relationship among starch chain length, oil unsaturation and straw performance. Among seven starch straws, S-SO had the strongest hydrogen bond interaction (3289 cm-1) and relaxation time (0.96 ms). The S-CO had the highest relative crystallinity (16.82 %) and degree of double helix (1.535), hence resulting in the lowest water absorption and solubility values, the highest flexural strength (23.43 MPa), the highest ΔT value (9.93 °C) and ΔH value (4.79 J/g). S-RO had the highest thermal transition temperatures.


Subject(s)
Starch , Zea mays , Starch/chemistry , Zea mays/chemistry , Water/chemistry , Soybean Oil , Chemical Phenomena , Rapeseed Oil , Corn Oil
3.
AMB Express ; 14(1): 28, 2024 Feb 24.
Article in English | MEDLINE | ID: mdl-38400878

ABSTRACT

Lignin is main composition of agricultural biomass which can be decomposed through enzymatic hydrolysis by fungi. However, there are still needs to identify more efficient and effective fungal stain for biomass valorization. In this study, lignin degrading fungi from birch forest were screened for sustainable degradation of waste agricultural straws. The most effective strain was identified as Cerrena unicolor GC.u01 using 18 S rDNA gene-sequencing technology. Three different crop straws (corn stalk, rice and wheat straws) were used for the biotreatment studies. The activities of lignin degrading enzymes, laccase (Lac), cellulase and xylanase, secreted by C. unicolor were also determined. Scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR) and thermal gravimetric analyzer (TGA) were further used to monitor the effects of the biotreatment process. The results showed that C. unicolor degraded 34.3% rice straw lignin, a percentage which was higher than other isolated strains after 15 d straw liquid fermentation. The highest Lac activity (8.396 U•mL- 1) was observed with corn stalk on the 7 d. Cellulase and xylanase activities, in the same biomass, were higher than those of wheat and rice straws after 15 d. Furthermore, SEM, FTIR and TGA analyses showed that C. unicolor pretreatment process had significant effects on corn stalk, rice and wheat straws' structures. The newly isolated stain of C. unicolor demonstrated high lignin degradation potential that can provide effective, ecofriendly means of valorizing biomass to industrial useable raw-material.

4.
J Hazard Mater ; 467: 133663, 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38325095

ABSTRACT

Incorporating spent coffee grounds into single-use drinking straws for enhanced biodegradability also raises safety concerns due to increased chemical complexity. Here, volatile organic compounds (VOCs) present in coffee ground straws (CGS), polylactic acid straws (PLAS), and polypropylene straws (PPS) were characterized using headspace - solid-phase microextraction and migration assays, by which 430 and 153 VOCs of 10 chemical categories were identified by gas chromatography - mass spectrometry, respectively. Further, the VOCs were assessed for potential genetic toxicity by quantitative structure-activity relationship profiling and estimated daily intake (EDI) calculation, revealing that the VOCs identified in the CGS generally triggered the most structural alerts of genetic toxicity, and the EDIs of 37.9% of which exceeded the threshold of 0.15 µg person-1 d-1, also outnumbering that of the PLAS and PPS. Finally, 14 VOCs were prioritized due to their definite hazards, and generally higher EDIs or detection frequencies in the CGS. Meanwhile, the probability of producing safer CGS was also illustrated. Moreover, it was uncovered by chemical space that the VOCs with higher risk potentials tended to gather in the region defined by the molecular descriptor related to electronegativity or octanol/water partition coefficient. Our results provided valuable references to improve the chemical safety of the CGS, to promote consumer health, and to advance the sustainable development of food contact materials.


Subject(s)
Coffee , Volatile Organic Compounds , Humans , Food , Gas Chromatography-Mass Spectrometry , Octanols , Polypropylenes
5.
Bioresour Technol ; 396: 130442, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38354961

ABSTRACT

This work investigated the effect of oscillation-assisted hydrothermal process on extraction of caffeic acid and ferulic acid from sorghum straws. The results showed that the oscillation-assisted hydrothermal process efficiently improved extraction of caffeic acid and ferulic acid. The oscillation-assisted hydrothermal process resulted in the extraction rates of 1275.48 and 1822.64 mg/L.h for caffeic acid and ferulic acid, respectively. Moreover, the oscillation-assisted hydrothermal process exerted destructive effects on hemicellulose, lignin and the amorphous regions of cellulose, contributing to the release of caffeic acid and ferulic acid in pretreated sorghum straws. The scavenging activities for hydroxyl, 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid radicals of the caffeic acid and ferulic acid extracts obtained by the oscillation-assisted hydrothermal process were determined to be 83.69 %, 84.17 % and 88.45 %, respectively.


Subject(s)
Sorghum , Caffeic Acids , Coumaric Acids
6.
Article in English | MEDLINE | ID: mdl-38397618

ABSTRACT

Plastic straws have become the poster child of waste associated with unnecessary single-use plastics. The visibility of straws littering the land and marine environments has influenced proposals to decrease the use of plastic straws. These include bans on plastic straws at the city, state, and national levels and by many corporations. However, most hospitals continue to use plastic straws in hospital dining areas and for patients. Hospital dining areas are like other public dining areas, so eliminating plastic straws should be straightforward. Regarding the use of straws by patients, we review evidence and propose that patients should not be routinely given straws. Instead, physicians and nursing staff should request straws depending on the patient's medical needs. Plastic straws make up only a tiny fraction of hospital waste but can be a catalyst to create awareness and decrease unnecessary plastic use in other areas of the hospital. Mitigating climate change requires a concerted effort from hospital leadership and healthcare providers. Only then will hospitals be able to fulfill their climate pledge of net zero emissions by 2050.


Subject(s)
Hospitals , Plastics , Humans , Patient Care , Patients
7.
Carbohydr Polym ; 321: 121297, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37739530

ABSTRACT

To study the relationship between the number of hydroxyl groups of polyols and the plasticizing effect, the effects of different polyols including ethylene glycol, glycerol, erythritol, xylitol and sorbitol on the structure and properties of corn starch straws were analyzed and compared. The results showed that the addition of plasticizer significantly improved the performance of starch straws, which greatly improved the mechanical properties, water absorption rate (WAR) and thermal stability. However, there was no linear relationship between the plasticizing effect on starch straws and the number of hydroxyl groups in plasticizers. Fourier transform infrared (FTIR) results showed that erythritol formed the strongest intermolecular interaction with starch. Starch straws with erythritol (S-ERY) had the highest bending force (Fb = 25.78 N) and the lowest WAR. Starch straws with glycerol (S-GLY) showed the lowest relative crystallinity (RC = 12.87 %) and the highest temperature of the maximum degradation (Tdmax = 302.1 °C). In addition, after storing for 180 days, S-GLY showed higher modulus of elasticity in bending (Eb = 4.26 N/cm) and a uniform surface.


Subject(s)
Erythritol , Glycerol , Elasticity , Hydroxyl Radical , Plasticizers , Starch , Water
8.
Foods ; 12(12)2023 Jun 06.
Article in English | MEDLINE | ID: mdl-37372491

ABSTRACT

Sugarcane processing produces a significant amount of byproducts in the form of straw and bagasse, which are rich in cellulose, hemicellulose, and lignin. This work aims to provide a valorization approach to sugarcane straw by optimizing a two-step alkaline extraction of arabinoxylans by a response surface methodology to evaluate a potential industrial-scale production. Sugarcane straws were delignified using an alkaline-sulfite pretreatment, followed by alkaline extraction and precipitation of arabinoxylan, a two-step process optimized using a response surface methodology. A KOH concentration of (2.93-17.1%) and temperature (18.8-61.2 °C) were chosen as independent variables, and the arabinoxylan yield (%) as a response variable. The model application shows that KOH concentration, temperature, and the interaction between both independent variables are significant in extracting arabinoxylans from straw. The best-performing condition was further characterized by FTIR, DSC, and chemical and molecular weight evaluation. The straws arabinoxylans presented high purities levels, ca. 69.93%, and an average molecular weight of 231 kDa. The overall estimated production cost of arabinoxylan from straw was 0.239 €/g arabinoxylan. This work demonstrates a two-step alkaline extraction of the arabinoxylans method, as well as their chemical characterization and economic viability analysis, that can be used as a model for industrial scale-up production.

9.
Polymers (Basel) ; 15(12)2023 Jun 14.
Article in English | MEDLINE | ID: mdl-37376318

ABSTRACT

The aim of the study was to assess the usefulness of agricultural biomass residues as reinforcement in recycled polymer matrices. In this study, recycled polypropylene and high-density polyethylene composites (rPPPE) filled with three types of biomass residues, sweet clover straws (SCS), buckwheat straws (BS) and rapeseed straws (RS), are presented. The effects of the fiber type and the fibers content on the rheological behavior, mechanical properties (including tensile, flexural and impact strength), thermal stability and moisture absorbance were determined, in addition to morphological analysis. It was revealed that the addition of SCS, BS or RS increased the materials' stiffness and strength. The reinforcement effect increased as the loading of the fibers was increased, especially for BS composites in the flexural test. After the moisture absorbance test, it was found that the reinforcement effect slightly increased for the composites with 10% fibers but decreases with 40% fibers. The results highlight that the selected fibers are a feasible reinforcement for recycled polyolefin blend matrices.

10.
Environ Sci Pollut Res Int ; 30(30): 75002-75014, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37208510

ABSTRACT

A new plastic ban has banned the use of single-use non-degradable plastic drinking straws in China's food and beverage industry by the end of 2020. However, this has caused widespread discussion and complaints on social media. What are consumers' reactions and what factors influence consumers to choose bio-straws (substitutes for plastic straws) are unclear. Therefore, this research collected 4367 effective comments (177,832 words in total) on "bio-straws" from social media and extracted keywords based on grounded theory to generate questionnaires. Structural equation modeling was used to analyze the consumption intention and influencing factors of 348 consumers regarding the ban. The results indicate the following: (1) consumer opinion on straws can be summarized into five main categories, namely, consumers' user experience, consumer subjectivity, policy awareness, policy acceptance, and consumption intention; (2) consumer subjectivity, policy awareness, and policy acceptance directly affect consumption intention significantly, while user experience affects consumption intention indirectly; and (3) user experience and consumer subjectivity play significant roles in mediating these relationships. From the perspective of consumers, this study provides an important basis for policymakers to formulate single-use plastic alternative policies in the future.


Subject(s)
Attitude , Intention , Humans , Food , Surveys and Questionnaires , Consumer Behavior
11.
Materials (Basel) ; 16(6)2023 Mar 18.
Article in English | MEDLINE | ID: mdl-36984318

ABSTRACT

Current biodegradable drinking straws suffer from poor heat resistance and rigidity when wet, causing user dissatisfaction. Here, a fully biodegradable straw formed by stereocomplexation of poly (lactic acid) (SC-PLA) is reported. Because of the unique strong interaction and high density of link chains between stereocomplex crystallites (over 70% crystallinity), SC-PLA straws outperform their counterparts on the market. This coupled with the advantages of simple processing (solution casting and annealing) and relatively low cost (~2.06 cents per straw) makes SC-PLA drinking straws a superior substitute for plastic ones. Commercially available PLLA straws lose almost 60% of their flexural strength when wet compared to less than 5% of the SC-PLA straws proposed in this study.

12.
Environ Pollut ; 323: 121332, 2023 Apr 15.
Article in English | MEDLINE | ID: mdl-36822313

ABSTRACT

Nitrated aromatic compounds (NACs) are important components of brown carbon (BrC), and their health and climate effects are of wide concern. Biomass burning is a major contributor to NACs in the atmosphere, yet NACs emitted from biomass burning are poorly constrained. In this study particulate NACs from open burning of corn straws were characterized in terms of their compositions, light absorption and toxic equivalents. 1, 6-dinitropyrene was the most abundant species among the measured nitropolycyclic aromatic hydrocarbons (NPAHs) with a share of 13.4% in total NPAHs, while 4-nitrocatechol was the most abundant nitrophenol (NP) species and accounted for 25.4% of measured NPs. 2-nitropyrene, widely used as a marker of secondary formation of NPAHs, was found to be the second most abundant NPAHs (13.3% of the total NPAHs) in the particulate matter (PM) primarily emitted from corn straw burning, and thus is inappropriate to be an indicator of the secondary formation. The measured primary NACs could only explain a negligible part (0.2%) of the light absorption by BrC. Although the concentrations of 9 toxic NACs were less than one-third of the 16 USEPA priority PAHs, their benzo(a)pyrene toxic equivalency quotients however were approximately 10 times that of the 16 PAHs. This study suggests that in comparison of PAHs from straw burning, NACs should be given greater attention due to their potentially higher toxic effects.


Subject(s)
Air Pollutants , Polycyclic Aromatic Hydrocarbons , Air Pollutants/analysis , Nitro Compounds , Zea mays , Particulate Matter/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Dust , Coal/analysis , Environmental Monitoring , China
13.
Polymers (Basel) ; 15(2)2023 Jan 12.
Article in English | MEDLINE | ID: mdl-36679291

ABSTRACT

The chemical recycling of end-of-life polylactic acid (PLA) plays roles in mitigating environmental pressure and developing circular economy. In this regard, one-pot tandem alcoholysis and hydrogenation of PLA was carried out to produce 1,2-propanediol, which is a bulk chemical in polymer chemistry. In more detail, the commercially available Raney Co was employed as the catalyst, and transformation was conducted in ethanol, which acted as nucleophilic reagent and solvent. Single-factor analysis and Box-Behnken design were used to optimize the reaction conditions. Under the optimized condition, three kinds of PLA materials were subjected to degradation. Additionally, 74.8 ± 5.5%, 76.5 ± 6.2%, and 71.4 ± 5.7% of 1,2-propanediol was yielded from PLA powder, particle, and straws, respectively, which provided a recycle protocol to convert polylactic acid waste into value-added chemicals.

14.
Int J Speech Lang Pathol ; 25(1): 15-19, 2023 02.
Article in English | MEDLINE | ID: mdl-36503285

ABSTRACT

PURPOSE: This paper relates to the Sustainable Development Goal (SDG) Life Below Water (SDG 14) and the need to consider Better Health and Well-Being (SDG 3) in interventions designed to reduce plastic straw waste. The aim of this paper is to explore the competing demands of saving the world's oceans and sea life from plastic straw waste, and simultaneously meeting the health and social needs of people with swallowing or physical disability who use plastic straws for drinking. RESULT: In order to meet both SDG 14 and not compromise SDG 3 there is a need for collaborative and interdisciplinary, person-centred, inclusive innovation approaches to finding suitable and acceptable alternatives to plastic straws. Many people with swallowing disability will need a durable, flexible, and single-use straw that is resilient enough to withstand jaw closure without breaking. Co-design considerations include the alternative straw being (a) soft and flexible so as not to damage the teeth of people who bite to stabilise the jaw or who have a bite reflex; (b) suitable for both hot and cold drinks; (c) flexible for angling to the mouth; (d) readily, thoroughly and easily cleaned to a high standard of hygiene; (e) widely available for low or no cost wherever drinks are served; and (f) safe for people to use while reducing impact on the environment and being sustainable. CONCLUSION: Plastic straws are an assistive technology critical for the social inclusion of people with disability. In an inclusive society, reaching a policy position on the provision of plastic straws must include seeking out and listening to the voices of people with sensory, intellectual, physical, or multiple disabilities who use plastic straws.


Subject(s)
Disabled Persons , Turtles , Humans , Animals , Sustainable Development , Water , Deglutition
15.
Adv Sci (Weinh) ; : e2205554, 2022 Nov 20.
Article in English | MEDLINE | ID: mdl-36403230

ABSTRACT

Among plastic items, single-use straws are particularly detrimental to marine ecosystems because such straws, including those made of poly(lactic acid) (PLA), are sharp and extremely slowly degradable in the ocean. While paper straws are promising alternatives, they exhibit hydration-induced swelling even when coated with a non-degradable plastic coating and promote effervescence (fizzing) in soft drinks owing to their surface heterogeneities. In this study, upgraded paper straw is coated with poly(butylene succinate) cellulose nanocrystal (PBS/CNC) composites. CNC increases adhesion to paper owing to their similar chemical structures, optimizes crystalline PBS spherulites through effective nucleation, and reinforces the matrix through its anisotropic and rigid features. The straws are not only anti-fizzing when used with soft drinks owing to their homogeneous and seamless surface coatings, but also highly water-resistant and tough owing to their watertight surfaces. All degradable components effectively decompose under aerobic composting and in the marine environment. This technology contributes to United Nations Sustainable Development Goal 14 (Life Below Water).

16.
J Voice ; 2022 Nov 07.
Article in English | MEDLINE | ID: mdl-36357237

ABSTRACT

OBJECTIVE: The objective was to quantify the range of airflow resistance and oral pressure attainable with variation of length, diameter, and water immersion depth of tubes and straws. STUDY DESIGN: Pressure-flow equations for tubes, determined previously for variable tube geometries, were used to calculate oral pressure ranges. Human subjects were then recruited to use the variable tube geometries to produce oral pressures, which were quantified with commercial manometers. RESULTS: Nomograms for airflow resistances and oral pressures are plotted as a function of tube length, tube diameter, and water insertion depth. CONCLUSIONS: It is shown that tube diameters in the range of 2.5-3.0 mm with tube lengths of 10-40 cm produce oral pressures in the range of 10-40 cm H2O. Insertion of the distal end into water adds a pressure in the amount of the depth of insertion. Maximum power transfer with different tube geometries is discussed.

17.
HardwareX ; 12: e00366, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36263160

ABSTRACT

The goal of this work was to develop prototypes of open-hardware vitrification devices for sperm cryopreservation that can be integrated with existing straw platforms. The open-hardware Vitrification Device for French Straws (VD-FS) is low-cost, customizable, 3-D printable, standardized, and allows long-term sample storage and identification. The feasibility was shown for vitrifying and storing samples with multiple configurations. The results can be improved by design alternation and evaluation of various vitrification solutions. This is the first complete open-hardware vitrification device that can be integrated with existing French-straw storage systems, providing a foundation for future community-level modifications and improvements.

18.
J Colloid Interface Sci ; 628(Pt A): 1-9, 2022 Dec 15.
Article in English | MEDLINE | ID: mdl-35908426

ABSTRACT

Benefiting from excellent mechanical properties, large surface area, rich hydroxyl groups, good sustainability, etc., nanocellulose is highly promising for various applications. However, intense chemical treatment and long-term processing are usually required to fabricate nanocellulose. Herein, a new synthesis method of nanocellulose is developed by using ultraviolet light irradiation-assisted delignification and subsequent sonification. This method is more cost-effective, time-saving, and environmentally benign compared to most of previously reported synthesis methods of nanocellulose. The obtained nanocellulose contains a small amount of lignin, which is unfavorable for high-temperature stability and optimal transparency. However, a small amount of lignin is beneficial to mechanical properties and in-water stability. With this nanocellulose, flexible MnO2 cathode film and hydrogel electrolyte are constructed and a quasi-solid-state zinc-ion battery is assembled. The battery exhibits 233.3 mAh g-1 after 1000 cycles at 1 A g-1 and 20 ℃. And more than half of that capacity can be maintained at -20 ℃. The battery also possesses great rate capability and good endurance to external forces. This work provides new insights into the synthesis and application of nanocellulose.


Subject(s)
Ultraviolet Rays , Zinc , Hydrogels , Lignin , Manganese Compounds , Oxides , Water
19.
Materials (Basel) ; 15(3)2022 Jan 25.
Article in English | MEDLINE | ID: mdl-35160869

ABSTRACT

A large amount of biomass straw waste is generated every year in the world, which can cause serious environmental pollution and resource waste if disposed of improperly. At present, biomass-derived porous carbon materials prepared from biomass waste as a carbon source have garnered attention due to their renewability, huge reserves, low cost, and environmental benevolence. In this work, high-performance carbon materials were prepared via a one-step carbonization-activation method and ball milling, with waste tobacco straw as precursor and nano-ZnO as template and activator. The specific surface area and porous structure of biomass-derived carbon could be controlled by carbonization temperature, which is closely related to the electrochemical performances of the carbon material. It was found that, when the carbonization temperature was 800 °C, the biochar possesses maximum specific surface area (1293.2 m2·g-1) and exhibits high capacitance of 220.7 F·g-1, at 1 A·g-1 current density in a three-electrode configuration with 6 M KOH aqueous solution. The capacitance retention maintained about 94.83% at 5 A·g-1 after 3000 cycles. This work proves the porous biochar derived from tobacco straws has a great potential prospect in the field of supercapacitors.

20.
Bioresour Technol ; 346: 126617, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34954358

ABSTRACT

The chemical compositions of lignin, hemicellulose and cellulose are so far unascertained to various lignocellulose in respect to effect of cellulose enzymatic hydrolysis. The novel and environment-friendly gluconic acid (GA) pretreatment technology showed impressive results on the enzymatic hydrolysis of cellulose in various agricultural straws. However, only few of the main reasons or critical issues pertaining to this reaction are known. Therefore, the novel GA pretreatment was carried out to remove hemicellulose from the three representative waste straws under different conditions. Next, for the enzymatic hydrolysis of the residual cellulose fraction in the pretreated straws, some mathematical correlations have been investigated between enzyme accessibility, hemicellulose removal rate, and cellulose crystallinity index. Both linear and nonlinear models were compared using five-parameter logic curve, four-parameter logic curve, and Deming regression. Hemicellulose removal was logically ascribed to be the trigger for cellulose saccharification efficiency during GA pretreatment of these waste straws.


Subject(s)
Cellulose , Lignin , Agriculture , Gluconates , Hydrolysis
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