Volume 9, Issue 7

Owing to the increasing global pollution due to the use of conventional plastic materials, biodegradable films and sheets have been given prominent importance owing to their efficiency in replacing traditional plastic materials. In the recent times, due to globalization and industrialization, the minimization of the use of synthetic petroleum-based materials has been in practice by the global community, and increase in the use of natural materials like biomass waste in place of traditional materials promoting the green and sustainable technology development. Such production of alternative biomaterials development from the lignocellulosic fiber-reinforced composite films and laminates has been seriously investigated by engineers, technologists, and materialists owing to their sustainability, renewability, low toxicity, and abundantly available. Banana is one among the largely consumed tropical crop globally which is due to the quantity of cultivation and the availability of calorific values in the fruit. It is also a fruit which is potentially rich in starch content with more than 65 % of starch. This banana starch can be considered as a potential material for the manufacturing of coating material, edible sheet, food preservation and packaging owing to its innocuous, less cost, and biodegradability. The application of banana starch is dictated by the functional, structural and physicochemical properties of the developed material. But an unmodified native banana starch may not be characterized with all the necessary properties for any customized application. In order to widen the application band of the banana starch, it has to be modified by using enzymes, chemical, and physical methods. This review comprehensively deals with the extraction and synthesis of banana starch from various sources, their modification, properties of the banana starch and its characterization. Some aspects regarding the hybridization of the banana starch with nanoparticles has also been given.

Araucaria Araucana starch is a raw material with proven potential in obtaining biodegradable polymers. Plasticization improves the flexibility characteristics of starch-based films, however, they still tend to have low tensile strength and high hydrophilicity. The addition of nanocellulose is a technique to improve these characteristics. In this paper, the effects of adding different sources and concentrations of nanocellulose (NC) on the properties of thermoplastic Araucaria Araucana films are addressed. One can highlight, the main effects are the increase of tensile strength and transparency of the films along with the reduction of water vapor permeability and water solubility. Further studies involving the reinforcement of Araucaria Araucana starch and nanocellulose should be conducted to overcome the lack of information.

Gluconic acid is one of the most important natural acids which are moderately generated from glucose via a straightforward oxidation reaction process. Through the use of microorganisms like Gluconobacter (bacteria) and fungi, the reaction is facilitated through various enzymes such enzyme glucose oxidase and glucose dehydrogenase. The typical widespread, fermentation procedure is characterized by the use of Aspergillus niger (fungi). The primary gluconic acid derivatives, such as sodium gluconate, are widely used in the agricultural and food industries. Gluconic acid has several uses in the pharmaceutical, food, beverage, textile, cement, metal chelating agent, leather, and dairy sectors. Commercial production of gluconic acid made by fungi is well-established. Therefore, fermentation procedures and effective microorganisms are employed to produce gluconic acid with a higher yield and higher quality. These processes are also more economical and effectively convert inexpensive substrates into carbon sources. Production of gluconic acid has been reported with corn starch, grapes must, banana must, egg shells, and potato pulp using both solid state and submerged fermentation. This article provides a thorough analytical analysis for the gluconic acid production through microbial fermentation and its uses in agriculture and food. Additionally, this contemporary paper thoroughly examines the literature from recent years on the growth of gluconic acid production for the global market.

Sustainable packaging development with lower environmental impact is urgent due to the petroleum-based plastic accumulation. Thereby, nanocellulose arouses the interest of several industrial sectors as renewable sources material and its mechanical properties for packaging manufacture. Biopolymers such as starch have been an alternative in packaging preparation, although its low mechanical and water resistance represents a challenge for its application. An alternative to improve these starch characteristics is nanocellulose incorporation. Thus, this chapter proposes obtaining nanocellulose from renewable sources, and its environmental advantage to replace plastics. Furthermore, types of nanocellulose, methods for obtaining, and the main physicochemical characteristics of nanocellulose are discussed since this polymer versatility allows its application in several industrial sectors, especially in packaging development. Finally, this review presents the incorporation nanocellulose-based nanocomposites in matrices, aiming to obtain formulations containing active agents to improve mechanical strength and water resistance and packaged product quality.

The use of case-based learning and team-based learning may help increase students’ self-concept in chemistry. The purpose of this study was to fill this gap by finding out the effects of case-based learning, team-based learning and regular teaching methods on secondary school students’ self-concept in chemistry in Maara Sub-County, Kenya. The study employed a 3 × 2 × 2 pre-test, post-test quasi-experimental factorial design. The study targeted 18,611 students in 52 secondary schools. Purposive sampling was used to choose three co-educational secondary schools with similar characteristics in Maara Sub-County. A total of 106 form two chemistry students were selected for the study using simple random sampling method. The experimental groups were taught using case-based learning and team-based learning while the control group was taught by regular teaching methods. The three groups were compared two-by-two to find out groups in which the differences in self-concept in chemistry would occur. Student’s self-concept questionnaire was administered to the students in the three groups. The validity of the instrument was ascertained by experts from Egerton University. Pilot testing was done in Meru South Sub-County in schools with similar characteristics. Reliability of the instruments estimated using Cronbach’s alpha coefficient was 0.81. Descriptive and inferential statistics were used for data analysis at α = 0.05. The mean differences in self-concept in the post-test were statistically significant among the three groups. The results of this study may offer valuable knowledge to policy makers as well as chemistry teachers so as to give greater attention to chemistry self-concept among students. The study findings fill a knowledge gap of effectiveness of methods of teaching chemistry.

Nanocellulose is a product of cellulose, a sustainable and plentiful resource. It’s distinctive nanoscale structure makes it a versatile, green and interesting material for a variety of applications. This article describes in detail the biosources of nanocellulose, the types and characteristics of nanocellulose, and the techniques used to produce nanocellulose fibers. The mechanical properties and morphologies of nanocellulose fibers are addressed in depth, along with their prospective applications in sectors, including paper packaging, building materials, composites, biomedicine, energy storage and filtration. In addition, the current state of nanocellulose research, including the opportunities in the field, as well as the future prospects of nanocellulose as a viable and sustainable material for a vast array of applications, are discussed.

As the fight against SARS-CoV-2 remains undefeated despite available vaccines, continuous efforts to curtail this deadly and highly spreading virus remain a world priority. In this research, we have investigated the antiviral properties of the phytochemicals from Annona muricata (Sour Sop) as potential inhibitors of SARS-CoV-2 main protease (M pro ) and Spike Receptor Protein. Pharmacokinetic analyses such as in-silico ADME, drug-likeness, PASS prediction, oral-bioavailability and bioactivity were carried out to screen the phytochemicals, 9 out of the 131 ligands satisfied the screening. A molecular docking approach was used to obtain the binding energies of the 9 ligands, and the result showed that Roseoside (−7.50 kcal/mol) and Coreximine (−7.0 kcal/mol) displayed the best docking score and have predicted to have stable interactions with SARS-CoV-2 main protease and Spike Glycoprotein. Data from this study could be further explored in developing multi-target drugs against SARS-CoV-2.

Ovarian cancer is a crucial gynaecological unmet medical disease with a high mortality rate. According to recent research, the phosphoinositol 3 kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathways are hyper-activated in the majority of ovarian cancer patients, necessitating the use of inhibitors. Over the years, phytochemicals have been used as alternative sources of therapeutic agents due to their reported biological activities and limited side effects. Curcuma longa (Tumeric), a reported ayurvedic medicine has also been noted for its anti-cancer properties. Thus, 155 phytochemicals from this plant and 2 reference drugs were evaluated for their inhibitory prowess against P13K/AKT receptor using a computer-aided drug design approach. The binding scores and inhibiting efficiencies were obtained via virtual screening. Molinspiration Chemoinformatics and SwissADME tools were used to investigate the drug-likeness properties and oral bioavailability of the compounds selected, while the ADMET SAR-2 website was used to conduct the Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) analysis. Other analyses performed on the selected compounds include bioactivity, activity spectra for substances (PASS) prediction, binding mode, and molecular interaction. The results revealed that Hopenone 1 (−8.8 kcal mol −1 ) and Epriprocurcumenol (−7.8 kcal mol −1 ) are potent inhibitors of the P13K receptor, while Epiprocurcumenol (−9.0 kcal mol −1 ), Procurcuminol (−8.6 kcal mol −1 ) and Curlone (−8.3 kcal mol −1 ) are potential inhibitors of AKT receptor. In comparison to Topotecan and Melphalan, they have better binding affinities, oral bioavailability, drug-likeness characteristics, ADMET properties, bioactivities, PASS properties, binding mechanism, and also interact well with the active site of the target receptor. As a result, this preliminary investigation suggests that these chemicals should be studied further for the design of novel ovarian cancer therapeutics.

While most commodity plastics were not designed to easily depolymerize, some common plastics can be broken down into their parent monomers in the presence of heat, pressure, catalysts, and/or solvent. Here, we provide a high-level overview of the depolymerization technologies that have been studied and/or scaled as promising monomer-loop recycling processes for selective plastic waste streams. Namely, commodity plastics that are considered unzippable/depolymerizable include polyethylene terephthalate, polyamides, polymethyl methacrylate, and polystyrene. Monomer-loop recycling technologies are one of several pathways toward a circular economy for plastics.

Background: The vulnerabilities and risks of women injecting drug users (WIDUs) are different compared to their male counterparts. In light of scant literature in this area, we carried out this qualitative study with the aim to explore the lived experiences of WIDUs in the North of Mauritius. Its objectives were (1) To get an insight into the risks taken during the injection practices of WIDUs and (2) To obtain an in-depth understanding of the gender-specific vulnerability of the sexual behaviours of WIDUs. Methods: A qualitative phenomenological approach was used for the research work. Study participants were recruited from a specific needle exchange site, by purposive sampling until saturation of data was reached. In-depth interviews conducted were transcribed for thematic analysis. Ethical clearance was obtained from the relevant authorities. Findings: The principal theme which emerged from the data collected was “Drug Injection Scenario”, with the following sub-themes: settings for drug injection; pre-injection rituals; third party assistance; sharing and recycling of injecting materials. The second theme which came out was “Sex Work and Drug Use Interplay” with either sex work preceding drug injection or drug injection preceding sex work. Finally, the third theme was “Sexual Behaviours Screenplay” with casual encounters and unprotected sex. Conclusions: This study filled the gap with respect to the absence of qualitative studies among WIDUs in Mauritius. It revealed their risky drug injecting practices and sexual behaviours. Their psychological and physical dependence on drug injection contributed to their stay within this vulnerable circle. Their inability to access adequate support hinders them from coming out of the clutches of their risky drug injection and sexual practices. For resilience of the society, there is need to address the needs of this vulnerable group of women.