Use of the black soldier fly Hermetia illucens L. (Diptera: Stratiomyidae) as an alternative source of chitin and chitosan for the production of biopolymeric films in agro-food applications

Chitin and chitosan are natural polymer of great technological and economic interest, finding several applications in many different fields. Chitin is a structural component of the exoskeleton of arthropods and the fungal cell wall, while chitosan is its main deacetylated derivative. Currently, chitin is industrially extracted from fishery waste, mainly crustacean shells. The debate on the sustainability of this resource and the constant increase in market demand for chitin and chitosan have driven the search for alternative sources. In this context, insects are gaining great interest. In recent decades, large-scale insect breeding facilities for feed production and organic waste disposal have arisen all over the world. These farms generate large amounts of insect waste biomass (i.e., exuviae left over from moulting processes and dead insects) rich in chitin that could be exploited as a source for the extraction of this polymer. The aim of this work was to investigate different insect biomasses (larvae, pupal exuviae and adults) generated from the farming of the dipteran Hermetia illucens (the most widely bred species in Europe) as sources of chitin and chitosan. Chitosan was produced with the purpose of being used for the production of coatings for the preservation of fresh fruits. From the three different sources of H. illucens, chitin with characteristics and purity similar to that commercially available from crustaceans was extracted. The highest yield (23%) was obtained from pupal exuviae. From the analysis of the composition of the material obtained after each step of the chitin extraction process, it was possible to calculate the efficiency of the extraction methods applied, which were suitable for removing components extraneous to chitin from the raw insect sample. The chitosan obtained from the deacetylation of chitin had some different characteristics than commercial chitosan, particularly a very low viscosity and molecular weight. This, together with the presence of impurities found in one sample, suggests the need to modify the deacetylation process or some parameters of the chitin extraction method. Chitosan produced from larvae, pupal exuviae and adults of H. illucens was used to produce coating solutions that were applied to cherry tomatoes, strawberries, apricots and nectarines. The preservative effect of the insect-derived chitosan coating was evaluated by investigating changes occurred in the weight, pH, titratable acidity and total soluble solids content of fruits during the storage period. Preliminary promising results were obtained from this investigation: chitosan from H. illucens had similar or, in some cases, better effects than commercial chitosan; often no different effects were observed in coated fruits than in uncoated fruits, but coating with chitosan had better effects than coating with only solvent solution (a non-optimal formulation of the solvent is hypothesised); chitosan obtained by homogeneous deacetylation always had worse effects than heterogeneous chitosan; it was observed that bleaching treatment applied to chitin may negatively affect the performance of the resulting chitosan. Furthermore, the chitosan coating was particularly effective in reducing and delaying spontaneous mould growth on the fruit during storage. This work has therefore highlighted the potential of H. illucens as a source of chitin and chitosan to be used in the agri-food sector as an alternative packaging. The results obtained are encouraging, although further studies are needed to fully optimise the extraction processes of these polymers in order to obtain the best characteristics for the desired applications

Manusia Sebagai Khalifatullah : Kajian Filosofis dalam Perspektif al-Qur`an

The article aims to reveal humans as khalifatullah: a philosophical study from the perspective of the Koran. This is important to do to provide a reference for how humans can think and act based on the tasks attached to them. This research is library research with a philosophical approach. The results of the research show that philosophically the Qur'an examines humans including discussing the purpose of life, position and duties of humans. Everything is related to human ontological thinking. Therefore, it is always inseparable from the Islamic perspective regarding the purpose of his life to worship, his position as a regulator and conservator of the earth, with his duties and functions as a servant of Allah, and as Allah's representative, substitute and successor to the species that preceded him, inheriting the earth as a form of Allah's trust that must be fulfilled. keep. So humans are leaders of themselves, their families and society, and based on this trust, humans are held accountable for the mandates they have received. The implication of the research is that narrative understanding brings synergistic philosophical understanding to the Muslim person so that he becomes a perfect Muslim. This research is expected to contribute to the philosophy of Islamic education

Erratum: Lipase-catalyzed regioselective acylation of resorcin[4]arenes (Journal of Molecular Catalysis B: Enzymatic (2002) 16 (24-247) PII: S1381117701000686)

10Immobilized lipase from Mucor miehei (RML) catalyzed the regioselective acylation of the C-2 side-chain of the C-alkyl resorcin[4]arene tetra-alcohol 1 in the 1,2-alternate form in organic solvents using vinyl acetate as acylating reagent. The influence of reaction parameters and solvent choice were also studied. Docking simulations allowed the determination of the binding geometry of 1, revealing the importance of Trp88 residue in stabilizing the Michaelis–Menten complex between enzyme and substrate.reservedmixedBotta, Bruno; Zappia, Giovanni; Tafi, Andrea; Botta, Maurizio; Manetti, Fabrizio; Cernia, Enrico; Milana, Giuliana; Palocci, Cleofe; Soro, Simonetta; Delle Monache, GiulianoBotta, Bruno; Zappia, Giovanni; Tafi, Andrea; Botta, Maurizio; Manetti, Fabrizio; Cernia, Enrico; Milana, Giuliana; Palocci, Cleofe; Soro, Simonetta; Delle Monache, Giulian

Analisi e ottimizzazione di una antenna compatta di tipo T-Bar a cavita' per la banda VHF/UHF

La tesi tratta una prima analisi di varie categorie di antenne in banda VHF/UHF (monopole like, eleven feed, cavity backed e t-bar and sleeve dipole). In particolare, essendo poco trattate, si è posto l'accento sul tipo T-Bar a cavità, di cui si è fatta una trattazione prima analitica e poi volta all'ottimizzazione della struttura stessa in vari step successivi. Alla fine è stata raggiunta una struttura tale da aver aumentato la banda percentuale della stessa, rispetto a quelle attualmente in commercio, di circa il 30%, diminuendo anche le dimensioni complessive

Current state of chitin purification and chitosan production from insects

Chitin, and especially its deacetylated variant chitosan, has many applications, e.g. as carrier material for pharmaceutical drugs or as a flocculant in wastewater treatment. Despite its versatility and accessibility, chitin, the second most abundant polysaccharide on Earth, has so far been commercially extracted only from crustaceans and to a minor extent from fungi. Insects are a viable alternative source of chitin, but they have not been exploited in the past due to limited availability. Today however, for the sustainable production of animal feed, insect farming is being developed substantially. The availability of large quantities of insect biomass and chitin-rich side products such as exuviae and exoskeletons has been increasing. This review provides an overview of recently published studies of chitin extraction from insects, its subsequent conversion into chitosan and the primary analytical methods used to characterize insect-based chitin and chitosan. We have discovered a large number of research articles published over the past 20 years, confirming the increased attention being received by chitin and chitosan production from insects. Despite numerous publications, we identified several knowledge gaps, such as a lack of data concerning chitin purification degree and chitosan yield. Furthermore, analytical methods used to obtain physicochemical characteristics, structural information and chemical composition meet basic qualitative requirements but do not satisfy the need for a more quantitative evaluation. Despite the current shortcomings that need to be overcome, this review presents encouraging data on the use of insects as an alternative source of chitin and chitosan in the future. © 2020 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI)

PEMETAAN KERUSAKAN JALAN DI KABUPATEN PONOROGO MENGGUNAKAN ALGORITMA K-MEANS

Pemetaan adalah pengelompokkan suatu kumpulan wilayah yang berkaitan dengan beberapa letak geografis wilayah yang meliputi : dataran tinggi, pegunungan, .sumber.daya dan potensi penduduk yang berpengaruh terhadap sosial kultural, Jalan termasuk salah satu contohnya. Terdapat banyak masalah di jalan mulai dari kerusakan jalan hingga kemacetan. Kerusakan jalan sudah tidak bisa dipungkiri dan sulitnya mendapat informasi kerusakan jalan suatu daerah. Jika daerah tersebut memiliki kerusakan wargapun awam dalam hal melaporkan daerah ponorogo yang memang memiliki tingkat kerusakan jalan cukup besar. Pemetaan kerusakan jalan memberikan informasi sekaligus aspirasi bagi masyarakat sehingga menghasilkan informasi tingkat kerusakan jalan di wilayah ponorogo. Mengambil sample dari 3 kecamatan diwilayah ponorogo terdapat 8 kecamatan Cluster 1 (Kerusakan Ringan), Cluster 2 (Kerusakan Sedang), Cluster 3 (Kerusakan Berat). Masing masing dihitung menggunakan.metode.K-Means

Readability of basic science textbooks for junior secondary schools in Enugu state, Nigeria

Introduction: Textbooks are essential component of the educational system that were heavily utilized by teachers and learners. Basic Science textbook authors should review the language structure and terminologies to enhance the readability of Basic Science textbooks. Purpose: The study aimed at analyzing the adequacy in the readability level of the recommended Basic Science textbooks in use junior secondary schools Enugu State, Nigeria.   Methodology:  An evaluation research design was adopted for this study. The population consisted of all the 60 recommended Basic Science that were approved for teaching of Basic Science in Junior Secondary Schools in Enugu state, Nigeria. The sample size of this study comprised of 33 recommended Basic Science textbook. Purposive sampling technique was used to draw eleven (11) recommended Basic Science textbooks each from JSS1, JSS 2 and JSS 3. The readability of the textbook was determined using Flesch-Kincaid Readability Formula. The researchers subjected the instrument to content validation by three experts, with internal consistency reliability estimate of 0.92. Microsoft office word 2010 was used to assess the readability. The mean of the readability scores for each Basic science textbooks was determined and interpreted using the Flesh’s interpretation readability scores relative to Nigerian schools. Results: The findings of this study revealed that almost all the Basic Science textbooks are adequate and can easily be understood by the students.  Recommendations: The researchers recommended that the recommendation of Basic Science textbooks should not be based on the reputation of the publishers and the lobbying abilities but should be based on more objective criteria that relate to the textbook quality with the students as the principal focus.

Insect Chitin-Based Nanomaterials for Innovative Cosmetics and Cosmeceuticals. Cosmetics

Chitin and its derivatives are attracting great interest in cosmetic and cosmeceutical fields, thanks to their antioxidant and antimicrobial properties, as well as their biocompatibility and biodegradability. The classical source of chitin, crustacean waste, is no longer sustainable and fungi, a possible alternative, have not been exploited at an industrial scale yet. On the contrary, the breeding of bioconverting insects, especially of the Diptera Hermetia illucens, is becoming increasingly popular worldwide. Therefore, their exoskeletons, consisting of chitin as a major component, represent a waste stream of facilities that could be exploited for many applications. Insect chitin, indeed, suggests its application in the same fields as the crustacean biopolymer, because of its comparable commercial characteristics. This review reports several cosmetic and cosmeceutical applications based on chitin and its derivatives. In this context, chitin nanofibers and nanofibrils, produced from crustacean waste, have proved to be excellent cosmeceutical active compounds and carriers of active ingredients in personal care. Consequently, the insect-based chitin, its derivatives and their complexes with hyaluronic acid and lignin, as well as with other chitin-derived compounds, may be considered a new appropriate potential polymer to be used in cosmetic and cosmeceutical fields. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

N-(4-Bromo­phen­yl)-2-[(1-cyclo­hexyl­meth­yl-1H-1,2,4-triazol-3-yl)sulfanyl]­acetamide

The title compound, C17H21BrN4OS, was synthesized as a potential reverse transcriptase (RT) inhibitor of the human immunodeficiency virus type 1 (HIV-1). In the molecule, there is an N—H⋯S hydrogen bond making a five-membered ring. In the crystal, mol­ecules are connected into centrosymmetric dimers via pairs of N—H⋯N and weak C—H⋯N hydrogen bonds. The crystal structure also features C—H⋯O inter­actions