Chitin deacetylases have been identified in several fungi and insects. They catalyse the hydrolysis of N-acetamido bonds of chitin, converting it to chitosan. Chitosans, which are produced by a harsh thermochemical procedure, have several applications in areas such as biomedicine, food ingredients, cosmetics and pharmaceuticals.

Systematic literature searches were conducted to identify all randomized clinical trials (RCTs), systematic reviews, and metaanalyses of dietary supplements for body weight reduction. Data sources were Medline, Embase, Amed, Cinahl, and the Cochrane Library. The search terms used were dietary supplements, food supplements, herbal products, phytotherapy, overweight, obesity, weight loss, slimming, and derivatives of these. Each database was searched from its inception until March 2003.

Chitin, poly-B-(1→4)-N-acetyl-D-glucosamine, is a cellulose-like biopolymer distributed widely in nature, especially in marine invertebrates, insects, fungi, and yeasts. Chitin and its deacetylated form, chitosan, have attracted significant interest in a broad range of applied scientific areas, including the biomedical, food, and chemical industries.

Foods are processed for a variety of reasons: to render them edible if they are not; to permit storage; to alter texture and flavor; and to destroy microorganisms, undesirable enzymes, and other toxins (1–4). Processing methods include heating (baking, cooking, frying, microwaving), freezing, aging, and exposure to acidic and basic conditions. Although processing of foods can improve nutrition, food microbiology, quality, and safety, these processing alternatives can occasionally lead to the formation of toxic compounds.

There are various model systems of host–parasite interactions that have contributed to our knowledge of signaling. This minireview will focus on disease resistance features, present and generated in the interactions between pea and Fusarium solani. Initially, both pea seedling and pea endocarp tissue systems were developed for studying the induction of the antifungal phytoalexin pisatin (17).

Four chitosan samples with different molecular weight M_w and the degree of deacetylation DD (HCS 7.60 · 10⁵ and 85.5%, MCS 3.27 · 10⁴ and 85.2%, COS 0.99 · 10³ and 85.7%, WSC 3.91 · 10⁴ and 52.6%) were prepared, and labeled by fluorescein isothiocyanate. These labeled samples were used to investigate the absorption and distribution in mice after oral administration.

Chitooligosaccharides (COS), with a polymerization degree of 2-8, were prepared by the enzymic hydrolysis of chitosan. The anti-angiogenic activity of COS in subcutaneous xenografts in mice has been studied for the first time. As nitric oxide (NO) plays a critical role in angiogenesis, we investigated the relationship between COS and the NO-mediated migration of endothelial cells. The results demonstrated that COS could suppress tumor angiogenesis and exhibit antioxidant activity by increasing the SOD activity in Kunming mice that were implanted with human breast cancer cells, dose-dependently.

Chitooligosaccharides (COS) was obtained from chitosan by depolymerization with enzyme and analyzed by HPLC and TOF-MS, and the results indicated that the polymerization degree of COS was 2–18. In order to explore the anti-angiogenic activities of COS, the effect of COS on chicken chorioallantoic membrane (CAM) angiogenesis and on proliferation, migration and tube formation of human umbilical vein endothelial cells (HUVECs) induced by human hepatoma carcinoma cells (HCC) culture fluid was measured.

N-Acetylchitooligosaccharide (N-acetyl-COs) was prepared by N-acetylation of chitooligosaccharide (COs). In vitro study using human umbilical vein endothelial cells (HUVECs) revealed that both N-acetyl-COs and COs inhibited the proliferation of HUVECs by inducing apoptosis.

In order to prevent the browning of the chitooligomer product prepared from enzymatic hydrolysis, the chitooligomers were reduced by potassium borohydride. The chemical structures and physical properties of the reduced chitooligomers were characterized by magnetic resonance spectra, X-ray diffraction, UV-spectrophotometry, thermogravimetric analysis, differential thermal analysis.

In this paper, we aimed to study the role of mannose receptor (MR) in oligochitosan induced RAW264.7 (a murine macrophage cell line) activation. Oligochitosan, which has 3–10 saccharide (N-acetyl-glucosamine or glucosamine) residues, was prepared by enzymatic hydrolysis of chitosan using cellulase.