Recent insights into the extraction, characterization, and bioactivities of chitin and chitosan from insects.

BACKGROUND: Insects are a living resource used for human nutrition, medicine, and industry. Several potential sources of proteins, peptides, and biopolymers, such as silk, chitin, and chitosan are utilized in industry and for biotechnology applications. Chitosan is an amino-polysaccharide derivative of chitin that consists of linear amino polysaccharides with d-glucosamine and N-acetyl-d-glucosamine units. Currently, the chief commercial sources of chitin and chitosan are crustacean shells that accumulate as a major waste product from the marine food industry. Existing chitin resources have some natural challenges, including insufficient supplies, seasonal availability, and environmental pollution. As an alternative, insects could be utilized as unconventional but feasible sources of chitin and chitosan. SCOPE AND APPROACH: This review focuses on the recent sources of insect chitin and chitosan, particularly from the Lepidoptera, Coleoptera, Orthoptera, Hymenoptera, Diptera, Hemiptera, Dictyoptera, and Odonata orders. In addition, the extraction methods and physicochemical characteristics are discussed. Insect chitin and chitosan have numerous biological activities and could be used for food, biomedical, and industrial applications. KEY FINDINGS AND CONCLUSIONS: Recently, the invasive and harmful effects of insect species causing severe damage in agricultural crops has led to great economic losses globally. These dangerous species serve as potential sources of chitin and are underutilized worldwide. The conclusion of the present study provides better insight into the conversion of insect waste-derived chitin into value-added products as an alternative chitin source to address food security related challenges.

Trends in the extraction, purification, characterisation and biological activities of polysaccharides from tropical and sub-tropical fruits - A comprehensive review.

Tropical and sub-tropical fruits are tremendous sources of polysaccharides (PSs), which are of great interest in the human welfare system as natural medicines, food and cosmetics. This review paper aims to highlight the recent trends in extraction (conventional and non-conventional), purification and analytic techniques of fruit polysaccharides (FPSs). The chemical structure and biological activities, such as immunomodulatory, anti-cancer, anti-oxidant, anti-inflammatory, anti-viral, anti-coagulant and anti-diabetic effects, of PSs extracted from 53 various fruits were compared and discussed. With this wide coverage, a total of 172 scientific articles were reviewed and discussed. This comprehensive survey from previous studies suggests that the FPSs are non-toxic and highly biocompatible. In addition, this review highlights that FPSs might be excellent functional foods as well as effective therapeutic drugs. Finally, the future research advances of FPSs are also described. The content of this review will promote human wellness-based food product development in the future.

Purified Essential Oil from Ocimum sanctum Linn. Triggers the Apoptotic Mechanism in Human Breast Cancer Cells.

BACKGROUND: Essential oil of Ocimum sanctum Linn. exhibited various pharmacological activities including antifungal and antimicrobial activities. In this study, we analyzed the anticancer and apoptosis mechanisms of Ocimum sanctum essential oil (OSEO). OBJECTIVE: To trigger the apoptosis mechanism in human breast cancer cells using OSEO. MATERIALS AND METHODS: OSEO was extracted using hydrodistillation of the leaves. Cell proliferation was determined using different concentrations of OSEO. Apoptosis studies were carried out in human breast cancer cells using propidium iodide (PI) and Hoechst staining. RESULTS: We found that OSEO inhibited proliferation (IC50 = 170 µg/ml) of Michigan cancer foundation-7 (MCF-7) cells in a dose-dependent manner. The OSEO also induced apoptosis as evidenced by the increasing number of PI-stained apoptotic nucleic of MCF-7 cells. Flow cytometry analysis revealed that treatment with OSEO (50-500 µg/ml) increased the apoptotic cells population (16-84%) dose dependently compared to the control. OSEO has the ability to up-regulate the apoptotic genes p53 and Bid and as well as elevates the ratio of Bax/Bcl-2. CONCLUSION: Our findings indicate that OSEO has the ability as proapoptotic inducer and it could be developed as an anticancer agent. SUMMARY: OSEO inhibited proliferation of MCF-7 cells with an IC50 of 170 µg/mLOSEO at 500 µg/mL increased the population of apoptotic cells by 84%OSEO up-regulated the expression of apoptotic genes and as well increased the Bax/Bcl2 ratio. Abbreviations used: BAX: BAX BCL2-associated X protein; BCL2: B-cell CLL/lymphoma 2; BID: BH3 Interacting domain death agonist; OSEO: Ocimum sanctum essential oil; DMSO: Dimethyl sulfoxide; DMEM: Dulbecco's modified Eagle medium; MCF-7: Michigan cancer foundation-7; RT-PCR: Real Time Polymerase Chain Reaction.

Phyto-synthesis of silver nanoparticles using Alternanthera tenella leaf extract: an effective inhibitor for the migration of human breast adenocarcinoma (MCF-7) cells.

In this study, phyto-synthesis of silver nanoparticles (AgNPs) was achieved using an aqueous leaf extract of Alternanthera tenella. The phytochemical screening results revealed that flavonoids are responsible for the AgNPs formation. The AgNPs were characterised using UV-visible spectrophotometer, field emission scanning microscopy/energy dispersive X-ray, transmission electron microscopy, fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction. The average size of the nanoparticles was found to be ≈48 nm. The EDX results show that strong signals were observed for the silver atoms. The strong band appearing at 1601-1595 cm(-1) correspond to C-C stretching vibration from dienes in FT-IR spectrum indicating the formation of AgNPs. Human breast adenocarcinoma (MCF-7) cells treated with various concentrations of AgNPs showed a dose-dependent increase in cell inhibition. The IC50 value of the AgNPs was calculated to be 42.5 µg mL(-1). The AgNPs showed a significant reduction in the migration of MCF-7 cells.

Synthesis of flexirubin-mediated silver nanoparticles using Chryseobacterium artocarpi CECT 8497 and investigation of its anticancer activity.

In this work, the synthesis of silver nanoparticles from a pigment produced by a recently-discovered bacterium, Chryseobacterium artocarpi CECT 8497, was achieved, followed by an investigation of its anticancer properties. The bacterial pigment was identified as flexirubin following NMR ((1)H NMR and (13)C NMR), UV-Vis, and LC-MS analysis. An aqueous silver nitrate solution was treated with isolated flexirubin to produce silver nanoparticles. The synthesised silver nanoparticles were subsequently characterised by UV-Vis spectroscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), X-Ray Diffraction (XRD), and Fourier Transform Infrared (FTIR) Spectroscopy methodologies. Furthermore, the anticancer effects of synthesised silver nanoparticles in a human breast cancer cell line (MCF-7) were evaluated. The tests showed significant cytotoxicity activity of the silver nanoparticles in the cultured cells, with an IC50 value of 36µgmL(-1). This study demonstrates that silver nanoparticles, synthesised from flexirubin from C. artocarpi CECT 8497, may have potential as a novel chemotherapeutic agent.

Antimetastatic and anti-inflammatory potentials of essential oil from edible Ocimum sanctum leaves.

Antimetastatic and anti-inflammatory activities of Ocimum sanctum essential oil (OSEO) have been assessed in this study. OSEO at the concentration of 250 µg/mL and above showed a significant ((*) P < 0.05) decrease in the number of migrated cancer cells. In addition, OSEO at concentration of 250 µg/mL and above suppressed MMP-9 activity in lipopolysaccharide (LPS) induced inflammatory cells. A dose-dependent downregulation of MMP-9 expression was observed with the treatment of OSEO compared to the control. Our findings indicate that OSEO has both antimetastatic and anti-inflammatory potentials, advocating further investigation for clinical applications in the treatment of inflammation associated cancer.

Protection of cadmium chloride induced DNA damage by Lamiaceae plants.

OBJECTIVE: To analyze the total phenolic content, DNA protecting and radical scavenging activity of ethanolic leaf extracts of three Lamiaceae plants, i.e. Anisomelos malabarica (A. malabarica), Leucas aspera (L. aspera) and Ocimum basilicum (O. basilicum). METHODS: The total polyphenols and flavonoids were analyzed in the ethanolic leaf extracts of the lamiaceae plants. To determine the DNA protecting activity, various concentrations of the plant extracts were prepared and treated on cultured HepG2 human lung cancer cells. The pretreated cells were exposed to H2O2 to induce DNA damage through oxidative stress. Comet assay was done and the tail length of individual comets was measured. Nitric oxide and superoxide anion scavenging activities of lamiaceae plants were analyzed. RESULTS: Among the three plant extracts, the highest amount of total phenolic content was found in O. basilicum (189.33 mg/g), whereas A. malabarica showed high levels of flavonoids (10.66 mg/g). O. basilicum also showed high levels of DNA protecting (85%) and radical scavenging activity. CONCLUSIONS: The results of this study shows that bioactive phenols present in lamiaceae plants may prevent carcinogenesis through scavenging free radicals and inhibiting DNA damage.

Evaluation of DNA damage in jewellery workers occupationally exposed to nitric oxide.

Nitric oxide is a metastable radical, reacts with oxygen to produce toxic nitrogen oxides (N(2)O(3), ONOO(-)) which damage DNA. Occupational exposure to nitric oxide leads to increased frequency of chromosomal aberrations in humans. In the present study the DNA damage among the jewellery workers occupationally exposed to nitric oxide was analyzed using buccal cell comet assay. The result of this study shows increased levels of DNA damage among jewellery workers. The habit of cigarette smoking among the jewellery workers has a synergistic effect on inducing DNA damage.