Valorization of food processing wastes and by-products for bioplastic production

The global plastic production is reaching new altitudes every year. Growing production of petroleum-based plastics has incurred in disposal issues raising the concerns of plastic pollution and impact to the environment. These issues have encouraged innovation and research activities in the field of bioplastics, offering alternatives for conventional plastics. In recent years, global bioplastic production has also witnessed tremendous growth and expansion. Some of the main drivers of this growth are innovative biopolymers such as Polylactic acid (PLA) and Polyhydroxyalkanoates (PHAs). However, industrial expenses to produce bioplastics are much higher when compared to petroleum-derived plastics (e.g. industrial PHA production is estimated to be 5–10 times more expensive than petroleum-derived polymers). In this regard, globally many researchers have investigated for more environmentally friendly and cost-effective alternatives to produce plastics. One potential option to pursue would be to explore agri-food wastes and by-products for bioplastic production. This would not only reduce the volume of wastes and by-products, but also production costs incurred. This review paper provides an overview of bioplastics, including production methods and possibilities of industrial food waste valorization for bioplastic production.     

Use of heat treatment for the development of protein-based bioplastics

The production of bioplastics from renewable and biodegradable sources could be a great potential option for the substitution of conventional plastics. In this way, raw materials and processing method have been investigated to improve their competitiveness in the actual market. However, the extra treatment that bioplastics must undergo to improve their properties are expensive, making them unfeasible. In this sense, a heat treatment in a conventional oven seems to be a potential low-cost option. This work aimed to evaluate the incorporation of a heat treatment at 50 °C in the process of protein-based bioplastic. For this, two proteins with different applications, absorption in hygiene (soy protein isolate) and food packaging (pea protein isolate), were selected to evaluate the versatility of this tentative post-treatment. In addition, two different mold temperatures (70 and 130 °C) and different exposure times of heat treatment (0, 4 and 24 h) were studied to evaluate the effect of them in the bioplastics properties and to select the most optimal processing method for each protein. In this context, mechanical properties and water uptake capacity were evaluated to study the influence of this post-treatment on them. The results showed that the processing conditions and the heat post-treatment could modulate the final properties of protein-based bioplastics, being potential materials to replace conventional plastics.     

Hydroxyapatite recovery from fish byproducts for biomedical applications

The solid waste that is generated during industrial fish processing causes environmental deterioration after it is discarded. However, these aquatic materials are a source of valuable compounds such as hydroxyapatite (HAp). HAp is a calcium phosphate with physicochemical and biological properties that are similar to those of native human bone. HAp has been used in biomedical material development because it is biocompatible and does not cause adverse effects. It has been combined with many other chemical compounds to improve their mechanical, structural, and bioactive properties and has noteworthy application benefits in the food supplement, drug delivery, cosmetology, odontology, and bone implant fields. In this review, recent research related to the isolation of HAp and the development of materials with health benefits due to its bioactive properties are discussed. Moreover, the HAp derived from industrial fish processing adds value to the byproduct and reduces the environmental risks caused by aquatic waste disposal in landfills.     

Challenges and opportunities of utilizing municipal solid waste as alternative building materials for sustainable development goals: A review

Strict environmental concern, depletion, and price hike of building construction materials are driving scientific studies for the search of alternative materials for building construction. To this end sustainable building materials could be a fruitful solution. This review aims to discern the environmental efficacy of solid waste management (SWM) and its relationship with four stimuli i.e., economic structure, regulatory structure, science, and time. The study also highlights the investigation of governance network to figure out the regulatory structure and governance of waste management. Extensive details on solid waste with their sources, recycling potential and their current utilization for substantial development are outlined. A throughout of the production process, properties, advantages, disadvantages, and the global economy of building material developed through recycling of solid waste are discussed. This article also deals with the sustainability, social, and environmental impact of green building materials. The study identifies the future direction for the effective utilization of solid waste for developing building materials. Further, the scope of the present also focusses on the concept of circular economy for developing construction materials through recycling of solid waste, which provides an easy reference for solid waste processing towards sustainability.     

Characterisation of aqueous waste produced during the clandestine production of amphetamine following the Leuckart route utilising solid‐phase extraction gas chromatography–mass spectrometry and capillary electrophoresis with contactless conductivity detection

Chemical waste from the clandestine production of amphetamine is of forensic and environmental importance due to its illegal nature which often leads to dumping into the environment. In this study, 27 aqueous amphetamine waste samples from controlled Leuckart reactions performed in Germany, the Netherlands, and Poland were characterised to increase knowledge about the chemical composition and physicochemical characteristics of such waste. Aqueous waste samples from different reaction steps were analysed to determine characteristic patterns which could be used for classification. Conductivity, pH, density, ionic load, and organic compounds were determined using different analytical methods. Conductivity values ranged from 1 to over 200 mS/cm, pH values from 0 to 14, and densities from 1.0 to 1.3 g/cm³. A capillary electrophoresis method with contactless conductivity detection (CE–C⁴D) was developed and validated to quantify chloride, sulphate, formate, ammonium, and sodium ions which were the most abundant ions in the investigated waste samples. A solid‐phase extraction sample preparation was used prior to gas chromatography–mass spectrometry analysis to determine the organic compounds. Using the characterisation data of the known samples, it was possible to assign 16 seized clandestine waste samples from an amphetamine production to the corresponding synthesis step. The data also allowed us to draw conclusions about the synthesis procedure and used chemicals. The presented data and methods could support forensic investigations by showing the probative value of synthesis waste when investigating the illegal production of amphetamine. It can also act as starting point to develop new approaches to tackle the problem of clandestine waste dumping.     

Tunable Boc modification of lignin and its impact on microbial degradation rate

A new type of modified lignin, lignin-p-Boc, was obtained through reaction with di-tert-butyl dicarbonate (Boc₂O) in aqueous media catalyzed by 4-dimethylaminopyridine (DMAP). Boc modification occurred regardless of type of lignin, was tunable, and proceeded well in recovering lignin at high purity from sodium lignosulfonate (a common byproduct from pulping industry; lignin content: 60%). Lignin-p-BOC was demonstrated as a potential reactive filler in green plastic and as a potential crosslinker in design of bioresorbable composite polymeric implants. Furthermore, the effect of the modification on breakdown rate of alkali lignin by microbes was investigated, and results showed that the modification substantially decreases the breakdown rate. The tunable Boc modification process was designed via a system thinking, including availability of raw lignin, economical/green modification, potentiality of drop-in-change to current thermoplastic processing, modification impact on microbial degradability/disposed environment at the end of use life; hence the holistic consideration makes this alternative method for upgrade of technical lignins very practical for future industrial application. Via “in-situ” forming “easily breakable covalent bonds” with existing thermopolymers inside, Lignin-p-BOCs are also promising to play an important role as both excellent binders via “random match” and reductants in transforming linear plastic waste into circular plastics.     

Nontarget screening of production waste samples from Leuckart amphetamine synthesis using liquid chromatography - high-resolution mass spectrometry as a complementary method to GC-MS impurity profiling

The established approaches of suspect and nontarget screening (NTS) using liquid chromatography–high-resolution mass spectrometry (LC-HRMS) are usually applied in the field of environmental and bioanalytical analysis. Herein, these approaches were employed on a forensic-toxicological application by analyzing different production waste samples from controlled amphetamine synthesis via Leuckart route to evaluate the suitability of this methodology for identification of route-specific organic substances in such waste samples. For analysis, two complementary LC techniques were used to cover a broad polarity spectrum. After data processing and peak picking using the enviMass software and further manual data restriction, 17 features were tentatively identified as suspects, three of which were subsequently identified with reference substances. All suspects had been previously identified in studies, in which gas chromatography–mass spectrometry (GC-MS) was successfully applied for synthesis marker assessment in waste and amphetamine samples. Remaining features with high signal intensity and assigned sum formula were selected for the attempt of structure elucidation. Seven potential synthesis markers were tentatively identified, which were not yet reported, except the sum formula of one compound, and which were partly also detected in real case waste samples afterward. The innovative application of the NTS approach using LC-HRMS for the analysis of aqueous amphetamine synthesis waste samples showed its suitability as extension to GC-MS analysis as it was possible to successfully identify seven new potential marker compounds, which are specific either for the conversion of the pre-precursors α-phenylacetoacetonitrile and α-phenylacetoacetamide to benzyl methyl ketone or for the subsequent Leuckart synthesis route after their conversion.     

Impact of food processing on the safety assessment for proteins introduced into biotechnology-derived soybean and corn crops

The food safety assessment of new agricultural crop varieties developed through biotechnology includes evaluation of the proteins introduced to impart desired traits. Safety assessments can include dietary risk assessments similar to those performed for chemicals intentionally, or inadvertently added to foods. For chemicals, it is assumed they are not degraded during processing of the crop into food fractions. For introduced proteins, the situation can be different. Proteins are highly dependent on physical forces in their environment to maintain appropriate three-dimensional structure that supports functional activity. Food crops such as corn and soy are not consumed raw but are extensively processed into various food fractions. During processing, proteins in corn and soy are subjected to harsh environmental conditions that drastically change the physical forces leading to denaturation and loss of protein function. These conditions include thermal processing, changes in pH, reducing agents, mechanical shearing etc. Studies have shown that processing of introduced proteins such as enzymes that impart herbicide tolerance or proteins that control insect pests leads to a complete loss of functional activity. Thus, dietary exposure to functionally active proteins in processed food products can be negligible and below levels of any safety concerns.     

Extraction of stearate salts from plastic materials used in pharmaceutical applications

Plastic materials are widely used in medical items such as solution containers, infusion sets, transfer tubing, devices, processing equipment and systems, filters, and the like. Components in medical items can leach out of such items when they are contacted by a therapeutic product or product-related solution. Stearic acid and stearate salts are commonly present in medical and food packaging, either as plastic additives, processing aids, or contaminants, and their leaching from plastics is well documented. With a pK(a) in the range of 5.1 to 5.6 and limited aqueous solubility (log P(o/w) greater than 8), the leaching of stearic acid (and its related metal salts) into pharmaceutical products is expected to be strongly dependent on the product's pH and polarity. In order to establish and understand the leaching behavior of stearate-containing materials, three compounds (stearic acid, calcium stearate, and zinc stearate) and four polymeric materials containing these compounds were contacted with aqueous buffers in the pH range of 2.5 to 11. The leached levels of calcium, zinc, stearate, palmitate, and total organic carbon (TOC) were measured in the resulting solutions and are reported. For materials containing only stearic acid or salts themselves, the extraction of these entities is pH-dependent. At low pH, the cation counter-ions of the stearate salts are extracted from the plastic materials by a process that can loosely be termed ion exchange. At intermediate pH, little or no extraction of the stearates occurs. At high pH, the stearates are extracted from the materials to a very limited extent due to the solubility of the acid and/or salts in the extraction medium.     

Streptomyces hygroscopicus K2509利用离子交换废水制备培养基发酵生产井冈霉素A

本文筛选出一株对离子交换废水耐受性能较好的井冈霉素A发酵菌株Streptomyces hygroscopicus K2509。通过测定总糖、还原糖、发酵液电容、井冈霉素A产量等发酵参数，用摇瓶试验对比了S. hygroscopicus K2509和出发菌株S. hygroscopicus K18的差异，用15L罐试验验证了两菌株在离子交换废水配制培养基中的代谢特性。在摇瓶实验中，S. hygroscopicus K2509井冈霉素A产量低于出发菌株，但其表现出较好的离子交换废水耐受能力；在15L发酵罐实验中，S. hygroscopicus K18和K2509井冈霉素A产量分别为18.9和20.2g/L，产率分别为0.45和0.31g/L·h。新筛选菌株可在离子交换废水配制培养基中实现井冈霉素A正常发酵，可有效利用井冈霉素A提取工序所产生的废水，降低产品成本。     

Potential health impact of environmental micro- and nanoplastics pollution

Micro- and nanoplastics are generated from plastics and have negative impacts on the environment due to their high level of fragmentation. They can originate from various sources such as fragments, fibers and foams. The large proportion of the waste and resistance to degradation means micro- and nanoplastics have become a serious global environmental problem, but there are few studies on their potential toxicity for human health. In this review, we discussed routes of exposure and the potential effects of micro- and nanoplastics to human health. Human beings could mainly be exposed to micro- and nanoplastics orally and by inhalation. The possible toxic effects of plastic particles are due to the potential toxicity of plastics themselves, and their combined toxicity with leachable additives and adsorbed contaminants. The potential risks for human health focused on their gastrointestinal toxicity and liver toxicity. The toxic mechanisms could involve oxidative stress, inflammatory reactions and metabolism disorders. More studies are needed to carry out and explore the potential toxicological mechanisms of micro- and nanoplastics and evaluate the combined toxicity of their adsorbed contaminants.     

Strategies for electrochemical detection in immunochemistry

In this review, the current status of research in electrochemical immunosensors is considered. We primarily focus on label-free and enzyme-labeled immunosensors, and the analytical capabilities of these devices are discussed. Moreover, the use of magnetic beads as new materials for immunosensors coupled with electrochemical sensing is also described, together with the application of new molecules such as aptamers as specific biorecognition elements. Examples of the applicability of these devices in solving various analytical problems in clinical, environmental and food fields are reported. Finally, the prospects for the further development of immunosensor technologies are shown.     

Antibiotics threats on vegetables and the perils of low income nations practices

Loose control on antibiotics usage, improper waste disposal, the use of reclaimed water in crop production, and other poor practices can enhance the antibiotic contamination of soil, water and the environment. These then threaten food safety and human health. Highly susceptible crops such as vegetables easily accumulate antibiotics and can be a viable route for the spread of antibiotics resistant bacteria and the induction of antibiotics resistant genes. This paper discusses common usages and negative impacts of antibiotics, and the extent of their contamination in various environmental components viz-a-viz their impact on vegetables. Peculiar challenges and practices related to low income nations (LINs) as well as their consequential effects are also discussed. Areas of future research that needs attention in LINs are succinctly presented. This review therefore will serve as tool to increase the awareness of consumers, food producers, environmentalists and policy makers on the impact of antibiotics and inadequate practices on vegetable production.     

Ethyl lactate as a potential green solvent to extract hydrophilic (polar) and lipophilic (non-polar) phytonutrients simultaneously from fruit and vegetable by-products

Phytonutrients extracted from natural resources are receiving much attention among researchers due to their highly antioxidative characteristics which prevent several degenerative diseases including cardiovascular diseases and cancers. These nutraceutical compounds can be used in food, pharmaceutical and cosmetic products as natural antioxidants, preservatives, colourants and functional foods. Huge volume of food wastes are generated from the processing industry and these low-value food residues are rich in various phytonutrients worth recovering. This approach of valorisation reduces the generation of food wastes and is cost-effective considering the cheap feedstock, reduced waste management expenses and high market value of extracted compounds. In light of the health and safety risks posed by commonly used organic extraction solvents derived from the petrochemical industry, there is a need to recover the phytonutrients using green, sustainable and efficient solvents that are safe for human consumption. This work discusses ethyl lactate as a safe, green, efficient and potentially cheap solvent to recover phytonutrients from fruit and vegetable by-products. Ethyl lactate is compared with other organic solvents commonly used from the aspects of safety, environmental impacts and efficiency. Current challenges when employing ethyl lactate are also discussed.     

Grass Pea and Neurolathyrism: Farmers’ perception on its consumption and protective measure in North Shewa, Ethiopia

Neurolathyrism in Ethiopia is caused by food dependency on grass pea (Lathyrus sativus L.). In the study area, a large proportion of the farmers are growing grass pea since it can withstand harsh environments. Socio-economic factors (poverty; lack of money to buy other food legumes) and environmental problems (such as water logging and frost hazards) influence consumption of grass pea. Most of the respondents have the idea that some chemical contained in grass pea causes a health problem. Different processing and preparation methods are used to prepare grass pea into different food forms. The major processing methods include washing and soaking, as the farmers apply these methods mainly because they assume that the chemical that causes lathyrism, scientifically known as β-ODAP (β-N-oxalyl-l-α,β-diaminopropionic acid) is reduced through washing and soaking. The farmers adopt different strategies to avoid the problem of lathyrism such as avoiding consumption of grass pea in the form that they suspect to cause the problem, blending/mixing with other crops, applying different processing/detoxification methods. Since grass pea is consumed with a fear of lathyrism, future research should concentrate either on developing grass pea varieties with safe level of β-ODAP content or improving the traditional/indigenous processing methods.     

Influence of processing on trichothecene levels

Trichothecene mycotoxins frequently occur in cereal grains that are intended for food production. The process of converting grains into food and drinks for consumers has significant effects on the levels of toxins in the final food. Surveillance of retail food and drinks of cereal origin demonstrates that trichothecenes do survive the production processes employed. Trichothecenes are relatively heat stable chemicals, with high water solubility, properties that affect their processing fate. It is known that the extent of transmission into final food products is dependent on the pattern of Fusarium infection in the grains. For dry-milled products, the most highly contaminated fractions are those that contain the whole or the outer portions of the grain. For wet milling, the trichothecenes primarily transfer to the aqueous fractions, the most contaminated streams enter the animal food chain, although there is no evidence of significant trichothecenes transmission into animal products. However, anomalies remain in the understanding of the processing effects of several major cereal processes used in European food production (e.g. baking and brewing).     

2016年南充市某食品厂酱卤肉制品生产加工过程中致病菌结果与讨论

目的 收集南充市某熟肉制品厂生产加工过程中致病菌的污染信息,为国家食品风险监测评估中心制定卫生规范提供可靠数据.方法 2016年在南充市某食品厂采集原辅料、中间产品、成品、终成品、环境样品(熟区).根据《2016年熟肉制品(预包装)生产加工过程监测工作手册》中相关规定,结合国家现行标准方法进行.阳性菌株采用bioMerieux,Inc提供的革兰氏阳性和革兰氏阴性鉴定卡在VITEK2 compact全自动细菌生化鉴定仪进行鉴定.结果 在所采集的5类120份样品中,共分离出食源性致病菌19株,总检出率为15.8％.全年检出的沙门氏菌的血清型多样,包括肯塔基沙门氏菌、圣地亚歌沙门氏菌、塞罗沙门氏菌、山夫登堡沙门氏菌、瓦诺沙门氏菌和班吉沙门氏菌.结论 酱卤肉制品生产加工过程中,原辅料和环境中均存在多种致病菌,原辅料中携带的致病菌经过高温蒸煮之后能够被杀灭.但是在环境熟区中仍然检出了较多致病菌,这些致病菌很有可能在工人生产加工过程中被携带入产品,最终造成产品被污染.生产企业除了应该重视对产品的消毒灭菌外,还应该对环境中的致病菌提高警惕.为避免交叉污染,生产企业还应注意生产过程生熟区分开,盛装产品的设备等分开,为最终生产出合格的产品提供有力保障.