Article

Physical changes of chitin and chitosan in canine gastrointestinal tract

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

Physical changes of chitin and chitosan were evaluated in canine gastrointestinal tract. Chitin and chitosan were packed into nylon bags (3×1 cm2, 45 μm mesh) and administered orally, and then the bags were recovered from the feces. Chitosan bags were also inserted surgically into the jejunum and colon. The changes in the weight of the bags were evaluated. Chitosan was decreased to <10% of its original weight and had formed a film, while chitin did not undergo any change in shape or weight. The loss of chitosan was about 40% and the weight loss of chitosan was observed in the colon routes. The weight loss of chitosan in the colon was observed in the presence of colonic contents. An in vitro study was also performed to investigate the physical change of chitosan after treatment with artificial gastric and intestine juices. The in vitro study showed that chitosan became a gel in artificial gastric juice and its weight decreased by 15%, but there were no such physical changes when it was placed in artificial intestinal juice. The present study showed that chitin did not undergo any changes in weight and shape in the gastrointestinal tract, whereas chitosan did. In addition, chitosan was found to be affected in the stomach and large intestine, but not in the small intestine.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... Although dogs originate from wolves that have diets low in invertebrates , their genome also contains chitinase protein-coding genes (Bussink et al., 2007) and chitinolytic activity has been found in extracts of the gastric mucosa of dogs (Cornelius et al., 1975) suggesting gene expression and secretion of chitinase. Degradation of chitin from squid pen in the gastrointestinal tract of dogs, however, was low (Okamoto et al., 2001), indicating a low digestive efficiency of chitinase for this specific source. In addition, microbial chitinolytic activity in the dogs was low, which may categorize chitin a nonfermentable fiber. ...
... Although dogs originate from wolves that have diets low in invertebrates , their genome also contains chitinase protein-coding genes (Bussink et al., 2007) and chitinolytic activity has been found in extracts of the gastric mucosa of dogs (Cornelius et al., 1975) suggesting gene expression and secretion of chitinase. Degradation of chitin from squid pen in the gastrointestinal tract of dogs, however, was low (Okamoto et al., 2001), indicating a low digestive efficiency of chitinase for this specific source. In addition, microbial chitinolytic activity in the dogs was low, which may make chitin a non-fermentable fiber. ...
... The BSF and YMW larvae contain approximately 5.4 and 2.8% chitin of DM (Finke, 2013). When applying the fractions of N from chitin of total N for these larvae from that study and assuming a 0% digestibility of chitin (Okamoto et al., 2001), the in vitro digestibility of chitin-corrected N would be 92.7% for BSF larvae and 95.6% for YMW larvae. These estimates are in close agreement with the average AA digestibility values of respectively 91.5 and 96.1% in the present study. ...
Article
Insects are considered as a sustainable protein source for future pet foods. Here we aimed to evaluate the protein quality of larvae of the black soldier fly (Hermetia illucens, BSF), housefly (Musca domestica, HF) and yellow mealworm (Tenebrio molitor, YMW) and to evaluate the fermentation characteristics of their indigestible fractions. Clean freeze-dried larvae were subjected to in vitro simulated canine gastric and small intestinal digestion. Undigested insect residues, shrimp chitin and fructooligosaccharides (positive control, FOS) were incubated for 48 h with inoculum with fresh feces from three dogs simulating large intestinal fermentation. The AA profiles differed among the larvae with proteins from BSF and YMW larvae containing more Val and less Met and Lys than HF larvae. The in vitro N digestibility of the HF (93.3%) and YMW (92.5%) was higher than BSF larvae (87.7%). The BSF larvae also had lower in vitro digestibility values for essential AA (92.4%) and non-essential AA (90.5%) compared to the larvae of the HF (96.6 and 96.5%) and YMW (96.9 and 95.3%). Gas production for FOS increased rapidly during the first 6 h. Low and similar amounts of gas were found for HF larvae and chitin whereas gas production slowly increased over 30 h and was slightly higher at 48 h for BSF than for chitin. Gas production for YMW increased considerably between 6 and 20 h. At 48 h, gas produced for undigested residues was comparable to shrimp chitin and lower than FOS (P < 0.001). Incubation with insect residues resulted in more N-acetylglucosamine than with shrimp chitin (P < 0.05), suggesting higher microbial degradation of insect chitin. Fecal microbiota from one dog appeared to be better able to ferment the undigested residue of YMW as gas production increased considerably between 6 and 20 h of incubation and was higher than for the microbiota from the other two dogs. The associated metabolite profile indicated that acetate, propionate and butyrate were the main fermentation products. Furthermore, formate was produced in relatively high amounts. It is concluded that the protein quality, based on the amino acid profile and digestibility, of selected insect larvae was high with the undigested insect fractions being at least partly fermented by the dog fecal microbiota. As the microbiota from one dog was better capable of fermenting the undigested residue of YMW larvae, it is of interest to further study the selective growth of intestinal microbiota in dogs fed insect-based food.
... Chitin was degraded in the rumen of sheep (Yoshino et al., 1990), while chitosan remained intact. Chitosan was found to be degraded in the stomach and large intestine of dogs (Okamoto et al., 2001) but not in the small intestine. ...
... reported significantly higher ADG in an antibiotic (chlortetracycline)-added diet than non-antibiotics and chitosan-added diets from 0-21 d in weanling pigs, and the effect was due to higher feed intake in the positive control group than in the other groups. Reports of in vitro studies showed that chitosans became a gel in artificial gastric juice but there were no such physical changes when placed in artificial intestinal juice (Okamoto et al., 2001). Chickens fed a commercial broiler diet containing 20% dried whey and 2 or 0.5% chitin had significantly improved weight gain compared to controls (Zikasis et al., 1982), and the feed efficiency ratio shifted from 2.5 to 2.38 due to incorporation of chitin in the feed. ...
Article
Full-text available
A total of 126 crossbred weanling pigs (average body weight of 6.3??.3 kg) were used to investigate the effect of chito-oligosaccharide (COS) on growth performance, nutrient digestibility, pH of gastro-intestinal tract (GI), intestinal and fecal microflora of young piglets. Pigs were allocated to three dietary treatments based on body weight and gender in a single factorial arrangement. Treatments were control (No COS), T1 (0.2% COS during starter (6-13 kg) and 0.1% COS during grower (13-30 kg) phases, and T2 (0.4% COS during starter (6-13 kg) and 0.3% COS during grower (13-30 kg) phases, respectively. Each treatment had 3 replicates and 14 pigs were raised in each pen. COS is a low molecular weight water-soluble chitosan that can be obtained from chitin of the crab shell after deacetylation with concentrated sodium hydroxide at high temperature and then further decomposition by chitosanase enzyme in the presence of ascorbic acid. For the starter and grower periods, there were no significant differences (p>0.05) in average daily gain (ADG) and feed to gain ratio among treatments. However, during the overall period (6-30 kg), T2 showed better (p
... The inspiration for the test came from Pavlov's conditioning experiments with dogs in which gastric secretions were redirected into a test tube [1] . Validation of in vitro test methods used to simulate digestion in animals has been established by many researchers [2][3][4][5] . ...
... Figure 1 shows cut cubes in marked sample trays. Artificial gastric or intestinal juice was prepared according to Okamoto et al. [2] and equilibrated at 38.6 o C, the internal body temperature of a dog. A 4 x 2 x 5 x 2 factorial designed was used with the 4 different chew products, 2 sizes (1.0 cm, 0.5 cm cubes), 5 time periods (1, 2, 4, 8, 12 hrs) and 2 types of juices (gastric or intestinal). ...
Article
Full-text available
Four pet chew treats from four different manufacturers were tested for digestibility using invitro tests in artificial gastric (stomach) and intestinal juices. In vitro tests were selected to determinethe digestibility of dog chews for humane reasons and were conducted under conditions that weredesigned to simulate the digestive system of dogs. The purpose of the tests was to rapidly andinexpensively determines the rate of degradation of a dog chew in the canine digestive tract to assessproduct safety for dogs. Dog chew pet treats that are swallowed whole, or in part, should degraderapidly in the canine digestive system to prevent potentially dangerous blockage. Tests were conductedon one cm and one-half cm cubes of dog chew products. Results of the tests clearly indicated that oneproduct outperformed all others in short-term (under 4 hrs) digestive tests. The Bone-A-Mint WheatFree formula degraded more rapidly than all other products in tests simulating canine gastric andintestinal juices. Tests conducted in this study will form the basis of an in vitro procedure that can beused as an industry standard to asses the safety of pet chew treats.
... Samples with a lower molecular weight and lower degree of deacetylation were found to be more susceptible substrates. On the other hand, chitosan was shown not to be affected by the environment of the small intestine [16]. ...
Article
Chitosan is a partially deacetylated polymer obtained from the alkaline deacetylation of chitin which is a glucose-based unbranched polysaccharide widely distributed in nature as the principal component of exoskeletons of crustaceans and insects as well as of cell walls of some bacteria and fungi. Chitosan exhibits a variety of physicochemical and biological properties resulting in numerous applications in fields such as waste and water treatment, agriculture, fabric and textiles, cosmetics, nutritional enhancement, and food processing. In addition to its lack of toxicity and allergenicity, and its biocompatibility, biodegradability and bioactivity make it a very attractive substance for diverse applications as a biomaterial in pharmaceutical and medical fields, where it has been used for systemic and local delivery of drugs and vaccines. It also has bioactive properties in its own right. This paper reviews current veterinary applications for chitosan including wound healing, bone regeneration, analgesic and antimicrobial effects. It also discusses the potential application of chitosan to drug and vaccine delivery in veterinary species. Given the restrictions imposed by financial and animal restraint considerations, especially in farming applications, the veterinary drug delivery areas most likely to benefit from chitosan are the delivery of chemotherapeutics such as antibiotics, antiparasitics, anaesthetics, painkillers and growth promotants to mucosal epithelium for absorption for local or systemic activity, and the delivery of immunomodulatory agents to the mucosal associated lymphoid tissue for induction or modulation of local immune responses. The properties of chitosan expected to enhance these functions are discussed, and the future research directions in this field are indicated.
... This is considered a main cause of the distension and in creased weight of the large intestine with its contents f De Groot, 1987;Leegwater et al., 1974;Walker, 1978). The individual chem ical units of the test substance, namely chitin and beta-glucan, are poorty digestible polysaccharides which have been shown to be fermented to SCFA by intestinal micr000ra (Casterline et al., 1997;Dongowski et al., 2002;Hirano et al., 1990;Longe et al., 1982;Okamoto et al., 2001). Caecal enlargement in response to the ingestion of poorly digestibte carbohydrates is generally con sidered of no toxicological concern UECFA, 1974; World Health Organization, 1987). ...
Article
Chitin-glucan is an insoluble biopolymer, composed of chitin and beta-(1,3)-D-glucan, that is a component of the fungal cell wall. This study was conducted to assess the safety of chitin-glucan from the mycelium of Aspergillus niger (Artinia brand) for use as dietary supplement and food ingredient. Chitin-glucan was fed to Wistar rats (20/sex/group) at dietary levels of 0, 1, 5 and 10% for 13 weeks. Clinical and neurobehavioural observations, growth, feed and water consumption, ophthalmoscopy, haematology, clinical chemistry, urinalysis, organ weights, necropsy and histopathological examination revealed no adverse effects of chitin-glucan. Rats fed chitin-glucan at 10% consumed more feed than controls, probably due to lower energy density of their diet. Water intake was increased slightly at all dose levels. These changes were not toxicologically significant. Full and empty caecum weights were increased in mid-dose males and high-dose males and females. This caecal enlargement was a physiological response to the consumption of a high amount of poorly digestible carbohydrate and considered of no toxicological concern. In conclusion, feeding chitin-glucan at dietary levels up to 10% for 13 weeks was tolerated without any signs of toxicity. This level corresponded to 6.6 and 7.0 g chitin-glucan/kg body weight/day in male and female rats, respectively.
... It is therefore not absorbed from the intestine in significant amounts. Limited digestion of chitosan by enzymes produced by bacteria in the intestine may occur (Okamoto et al., 2001; Zhang and Neau, 2002). Results of toxicity tests in rodents have shown that chitosan is relatively harmless following oral administration. ...
... Recently, chitosan has shown promise as a carrier in colon targeting, results suggesting that conjugation with a variety of substrates via its amine might be one of the important properties of chitosan for its successful use in colon targeting. However, Okamoto et al. 34 reported that chitosan was unable to prevent destruction due to its high biodegradability in the acidic media and thus rapidly dissolved in the gastric cavity; hence, it was unable to protect its drug load during passage through the stomach and small intestine. To guide the design of chitosan formulations for colon targeting, some chemical or other modifications on chitosan are necessary to suppress its high degradability. ...
Article
This paper investigates the design of novel polyelectrolyte complex (PEC) coacervates of chitosan (Ch) with gum Odina (GO) as potential candidates for colon targeting. Potentiometric titration experiments established that 1:1 charge stoichiometry occurred at a Ch/GO weight ratio of 1:5. The coacervate formed at pH 4.5 displayed the highest storage modulus (G′) values. FTIR, XPS, WAXS, TGA, and DSC results suggested the strong ionic (NH3 +···COO−) bond formation between these two biopolymers. Through in vitro viability tests, the pH-induced PECs were shown to be nontoxic. In vitro biodegradation rates of their microspheres revealed insolubility in simulated gastric fluid and simulated intestinal fluid and degradation by cellassociated portions of rat cecal and colonic enzymes rather than the extracellular portions. The microsphere of pH 3.0 showed the highest degradation, and LVSEM micrographs revealed notably high amount of macropores in cell-associated enzymes, in contrast to extracellular enzymes.
... Recently, chitosan has shown promise as a carrier in colon targeting, results suggesting that conjugation with a variety of substrates via its amine might be one of the important properties of chitosan for its successful use in colon targeting. However, Okamoto et al. 34 reported that chitosan was unable to prevent destruction due to its high biodegradability in the acidic media and thus rapidly dissolved in the gastric cavity; hence, it was unable to protect its drug load during passage through the stomach and small intestine. To guide the design of chitosan formulations for colon targeting, some chemical or other modifications on chitosan are necessary to suppress its high degradability. ...
Data
This paper investigates the design of novel polyelectrolyte complex (PEC) coacervates of chitosan (Ch) with gum Odina (GO) as potential candidates for colon targeting. Potentiometric titration experiments established that 1:1 charge stoichiometry occurred at a Ch/GO weight ratio of 1:5. The coacervate formed at pH 4.5 displayed the highest storage modulus (G′) values. FTIR, XPS, WAXS, TGA, and DSC results suggested the strong ionic (NH 3 + ···COO −) bond formation between these two biopolymers. Through in vitro viability tests, the pH-induced PECs were shown to be nontoxic. In vitro biodegradation rates of their microspheres revealed insolubility in simulated gastric fluid and simulated intestinal fluid and degradation by cell-associated portions of rat cecal and colonic enzymes rather than the extracellular portions. The microsphere of pH 3.0 showed the highest degradation, and LVSEM micrographs revealed notably high amount of macropores in cell-associated enzymes, in contrast to extracellular enzymes.
... It is a deacetylated to varying degrees form of chitin, widespread in nature component of exoskeleton of shrimps, crabs and insects (Koide, 1998;Singla and Chawla, 2001). Unlike chitin, COS is soluble in acidic solutions (Shahidi et al., 1999), and it is partially digested in the gastrointestinal tract of monogastric animals (Hirano et al., 1990;Okamoto et al., 2001). Chitosan is commercially manufactured from chitin, in the process of deacetylation, by treating chitin with a strong solution of sodium hydroxide at an elevated temperature (Singla and Chawla, 2001). ...
Article
Full-text available
Chitosan is a nontoxic polyglucosamine, widespread in nature, which is deacetylated to varying degrees form of chitin, a component of exoskeleton of shrimps, crabs, and insects. Since chitosan contains reactive functional groups, i.e., amino acids and hydroxyl groups, it is characterised by antimicrobial, anti-inflammatory, antioxidative, antitumor, immunostimulatory, and hypocholesterolaemic properties when fed as dietary additive for farm animals. This article reviews and discusses the results of studies on the effects of dietary chitosan and its oligosaccharide derivatives on performance and metabolic response in poultry and pigs, i.e. hematological, biochemical, and immunological blood characteristics, microbiological profile of intestines, intestinal morphology, and digestibility of nutrients, as well as on the quality of meat and eggs. The results of most of the experiments presented in this review indicate that chitosan used as a feed additive for poultry and pigs has some beneficial, biological effects, including immunomodulatory, antioxidative, antimicrobial, and hypocholesterolaemic properties. These properties of chitosan, unlike many other kinds of feed additives, were often reflected in improved growth performance (body weight gain and/or feed conversion ratio) of young animals, i.e. broiler chickens and weaned pigs.
... The importance of chitin and chitosan has grown partly because they represent a renewable and biodegradable source of materials, and partly because of the recent increased understanding of their functionality in various applications (Paterson and Kennedy, 1990). The uses of chitin, chitosan and its derivatives in various industrial sectors are presented in Table 2. 1 (Muzarrelli, 1983;Watanabe et al., 1992;Komazawa et al., 1993;Tokura et al., 1995;Hjerde et al., 1997;Okamoto et al., 1997Okamoto et al., , 2001Okamoto et al., , 2002Okamoto et al., , 2003Hagiwaraa et al., 1999;Ravi kumar, 2000;Tsigos et al., 2000;Khanal et al., 2001Khanal et al., , 2002Chow and Khor, 2002;Tsai et al., 2002;Miyatake et al., 2003;Muzzarelli and Muzzarelli, 2003;Synowiecki and Al-Khateeb, 2003;Sashiwa and Aiba, 2004;Senel and McClure, 2004;Han et al., 2005;Shahidi and Abuzaytoun, 2005;Juneja et al., 2006;Struszczyk, 2006;Burkhanova et al., 2007;Muzzarelli et al., 2007;Prashanth and Tharanathan, 2007;Shahidi, 2007). ...
Article
350 words maximum) Most prawns are prepared as frozen or canned meat and the remaining waste is used as a feed supplement or directly disposed on to the land, which affects the environment. Fresh prawn bio-waste contains protein, astaxanthin, flavor compounds and chitin. The use of chitin in various applications is limited due to its water insolubility. In this research, a new method is developed to prepare water-soluble colloidal chitin (WSCC) from prawn waste. WSCC having the percentage of degree of deacetylation same with that of chitin follows non-newtonian shear thinning behaviour. The characteristic study showed that the breakage of polymer chains during processing thus reduced the molecular weight and bulk density of WSCC. Therefore, functional properties of WSCC can be controlled by optimizing the processing conditions. Astaxanthin complex has attracted considerable interest in relation to its health benefits because of its powerful antioxidant activity. Traditional extraction of astaxanthin complex from prawn waste using organic solvents requires post-purification steps, creates solvent disposal problem and degrades the pigment. This research develops an efficient way of recovering astaxanthin complex from prawn waste that eliminates the problems associated with solvent extraction methods and offers possible recyclability of the solvents used.
... Chitosan is metabolized in the colon, a property that has been used to produce colon targeted formulations (26). Although evidence suggests that chitosan metabolism is likely to mainly take place in the colon, the concentration at acyclovir's absorption site may also have been decreased by enzymatic degradation in stomach (pepsin) and/or duodenum/ ileum (pancreatic enzymes) (27)(28)(29)(30)(31)(32). In addition, the presence of mucus may represent an unfavorable microenvironment and have hampered the access of chitosan to the mucosa to exert its permeability enhancing effect (33,34). ...
Article
Full-text available
The effects of chitosan hydrochloride on the oral absorption of acyclovir in humans were studied to confirm the absorption enhancing effects reported for in vitro and rat studies, respectively. A controlled, open-label, randomized, 3-phase study was conducted in 12 healthy human volunteers. Zovirax 200 mg dispersible tablets co-administered with doses of 400 and 1000 mg chitosan HCl were compared with Zovirax only. The expected increased absorption of acyclovir was not observed. On the contrary, mean area under the plasma concentration-time curve (AUC0-12 h) and maximal plasma concentration (Cmax) decreased following concomitant chitosan intake (1402 versus 1017 and 982.0 ng∙h/ml and 373 versus 208 and 235 ng/ml, respectively). In addition, Tmax increased significantly in presence of 1000 mg of chitosan from 1 to 2 h. The results of this study in human volunteers did not confirm an absorption enhancing effect of chitosan. Reference values were comparable to literature data, whereas addition of chitosan resulted in significant opposite effects on Cmax, Tmax and AUC. Additional studies are needed to investigate the cause of the discrepancy. The observed variability and complex potential interactions may complicate the use of chitosan HCl in oral pharmaceutical formulations.
... It is a deacetylated to varying degrees form of chitin, widespread in nature component of the exoskeleton of shrimps, crabs, and insects [3,4]. Different from chitin, chitosan is soluble in acidic solutions [5,6], and it is moderately digested in the gastrointestinal tract of mono-gastric animals [7,8]. Chitosan is commercially obtained from chitin through the deacetylation process, in this process chitin is treated with a strong solution of sodium hydroxide at a higher temperature [4]. ...
Article
Full-text available
The slow progress in the development of the subsector, particularly of alternative feed sources such as agro-industrial byproducts and unconventional feed resources, has deepened the gap in the availability of and accessibility to animal feed. Production of animal feed is highly resource demanding. Recently, it has been shown that increasing climate change, land degradation, and the recurrence of droughts have worsened the feed gap. In the backdrop of these challenges, there has been attention to food-not-feed components, which have great potential to substitute human-edible components in livestock feeding. Chitosan, a non-toxic polyglucosamine, is widely distributed in nature and used as a feed additive. Chitosan is obtained from the de-acetylation process of the chitin and is mostly present in shrimp, crabs, and insect exoskeletons, and has antimicrobial and antiinflammatory, anti-oxidative, antitumor, and immune-stimulatory hypo-cholesterolemic properties. This review article discusses the results of recent studies focusing on the effects of chitosan and chitin on the performance of dairy cows, beef steers, sheep, and goats. In addition, the effects of chitosan and chitin on feed intake, feed digestibility, rumen fermentation, and microbiota are also discussed. Available evidence suggests that chitosan and chitin used as a feed additive for ruminants including dairy cows, beef steers, sheep, goats, and yaks have useful biological effects, including immune-modulatory, antimicrobial, and other important properties. These properties of chitosan and chitin are different from the other feed additives and have a positive impact on production performance, feed digestibility, rumen fermentation, and bacterial population in dairy cows, beef steers, sheep, goats, and yaks. There is promising evidence that chitosan and chitin can be used as additives in livestock feed and that well-designed feeding interventions focusing on these compounds in ruminants are highly encouraged.
... Chitin is biocompatible and non-toxic for use in a variety of human applications [8]. By passing through the GI tract, chitin did not change in weight and shape whereas some of the polysaccharides such as chitosan and starch did [9]. In nature, chitin is considered as an insoluble component of many chitin-polymer biocomposites which increases hydrogen bonds between adjacent chains of polymers leading to greater strength [7]. ...
Article
Incorporation of nanofibers of chitin (NC), lignocellulose (NLC) and bacterial cellulose (BNC) in pectin was studied to improve prebiotic activity and gastrointestinal resistance of the pectin-nanofibers biocomposites for protection of probiotics under simulated gastrointestinal conditions. The biocomposites were prepared using various compositions of pectin and nanofibers, which were designed using D-optimal mixture method. The incorporation of the nanofibers in pectin led to a slow degradation of the pectin-nanofibers biocomposites in contrast to their rapid swelling. AFM analysis indicated the homogenous distribution of interconnected nanofibers network structure in the pectin-nanofibers biocomposite. FTIR spectra demonstrated fabrication of the biocomposites based on the inter- and intra-molecular hydrogen bonding and ionic interaction of pectin-Ca²⁺. XRD patterns revealed the amorphous structures of the biocomposites as compared to the crystalline structures of the nanofibers. Among the compositions, the optimal compositions were as follows: 60% pectin + 40% NC, 50% pectin + 50% NLC and 60% pectin + 40% BNC, where the prebiotic score, probiotic survival under simulated gastric and intestinal conditions were optimum. The optimal biocomposite pectin-NC exhibited the highest survival of the entrapped probiotic bacteria under simulated gastric (97.7%) and intestinal (95.8%) conditions when compared with the corresponding to free cells (76.2 and 73.4%).
... A quitina não é digerível por cães, mas a quitosana sim (Okamoto et al., 2001). Insetos são fonte de quitina, alguns gêneros de grilo podem apresentar 4,3 a 7,1% da MS das fibras na forma de quitina e 2,4 a 5,7% (peso seco) em quitosana (IBITOYE et al., 2018). ...
Chapter
Full-text available
Insetos constituem parte da alimentação natural de várias espécies de animais, como aves, suínos, peixes, cães e gatos, e são uma boa fonte de proteínas, gorduras, vitaminas, fibras e minerais para os animais. Dada a crescente demanda mundial por proteína animal e a veemente busca por recursos alimentares sustentáveis e que substituam parcial ou integralmente os ingredientes convencionalmente utilizados na nutrição animal, algumas espécies de insetos alimentícios têm se destacado. De modo geral, insetos se reproduzem e crescem com facilidade em cativeiro, podem se alimentar de resíduos orgânicos, têm baixa demanda por água e energia quando comparados a outras espécies de animais, e não exigem terras agricultáveis em sua produção. Os insetos podem ser fornecidos vivos, inteiros desidratados ou em forma de farinha, dependendo do nível tecnológico da produção e dos objetivos do fornecimento na alimentação animal. Nos últimos anos, diversos estudos científicos têm demonstrado o imenso potencial do uso de insetos e seus produtos na alimentação animal. Desse modo, a entomocultura, ou seja, a produção de insetos em cativeiro, tem se firmado como uma nova cultura zootécnica, atraindo a atenção de acadêmicos e empreendedores ao redor do mundo. Nesse capítulo será discutida a importância dos insetos como fonte de alimento sustentável, as principais espécies de insetos alimentícios utilizadas, os efeitos da inclusão de insetos na alimentação de animais não-ruminantes, bem como o panorama regulatório mundial dessa nova e disruptiva fonte de alimentação animal.
... Furthermore, cellulose as an important biopolymer and the most abundant renewable resource has been studied for protection of probiotics against gastrointestinal conditions by incorpor-ated in a pectin matrix. Lignocellulose mainly including cellulose, hemicellulose and lignin can be assessed as a prebiotic for encapsulation of probiotics [14][15][16]. Polysacch-aride nanofibers due to their nano-scale diameters reinforce the structure and compact the surface of entrapment matrices, thus promoting the residence time for probiotic cells in harsh conditions such as low pH juices and gastrointestinal conditions. In our previous research, pectin-non-starch nanofibers were investigated as new entrapment matrices [17] but combination of the nanofibers was not studied to enhance the survival of probiotics under gastro-intestinal conditions and low pH juices. ...
Article
Full-text available
Background and Objective: Increasing survivability of probiotics in low pH juices and in gastrointestinal conditions is important for probiotic food industry. Nanofibers can reinforce the structure of entrapment matrices protecting probiotics in harsh conditions. This study investigated pectin-based bionanocomposites improved with nanochitin, nanolignocellulose and bacterial nanocellulose to introduce a prebiotic gastrointestinal-resistant matrix for enhancing the survival of Bacillus coagulans as a probiotic. Material and Methods: The bionanocomposites with various compositions were designed using mixture design method. These were fabricated based on cross-linking of calcium ions with pectin for entrapment of Bacillus coagulans. The survivability of probiotic was evaluated at 4 o C or 25 o C over a 5-week storage in peach juice and under simulated gastrointestinal conditions. Results and Conclusion: The prebiotic score of the pectin-nanochitin-nanolignocellulose (50:25:25% w w-1) was determined as 1.36. The survivability of Bacillus coagulans entrapped within the pectin-nanochitin-nanolignocellulose matrix was ~65% under gastrointestinal treatment. The surface structure of the matrix was relatively smooth coherent, compact and wrinkled due to the three-dimensional arrangement of the nanofibers of chitin and lignocellulose incorporated within pectin. The highest survivability of the entrapped bacteria was ~68% compared to the survivability of the free cell (~53%) at the end of 5-week storage period. After 21 day storage in the juice, the survivability of the entrapped bacteria treated under sequential digestion was ~58% as compared to that of the free cell (~43%). The present findings proposed a promising prebiotic matrix to protect probiotics in low pH fruit juice and the gastrointestinal tract.
... So far, chitosan has been investigated for colonic drug delivery with animal models only, but due to the different microflora in animals, extrapolation into humans is uncertain (Edwards and Parrett, 1999). Dogs (Okamoto et al., 2001), rabbits, hens and sheep (Hirano et al., 1990) have shown varied digestive capabilities. Rat caecal matter is commonly used to assess chitosan-based colonic delivery systems , 1999a,b 2002Orienti et al., 2002;Zhang et al., 2002;Chourasia and Jain, 2004) and although the rat colonic microflora is similar to that in man, it is not identical (Donaldson, 1968) and there are differences between the digestion of polysaccharides in vivo in rats, and in vitro or in vivo studies in man (Edwards and Eastwood, 1995;Daniels et al., 1997). ...
Thesis
The colon has a unique immunological environment which makes it an interesting target for vaccine delivery. In addition, it has a near neutral pH and low proteolytic activity (favourable for antigen delivery). Before colonic immunisation was attempted in the laboratory using rodent models, these latter were characterised in terms of lymphoid tissue, gastrointestinal pH and gastrointestinal water content. There were more lymphoid follicles per centimetre in the colon of mice and rats than in the small intestine. The mean intestinal pH was lower in rodents than that in man, being less than pH 5.2 in the mouse and less than pH 6.6 in the rat. The mouse and rat had less than 1ml and 8ml of water respectively in the gastrointestinal tract. Immunisation studies were carried out in mice using ovalbumin as a model antigen (encapsulated in sustained release PLGA nanoparticles). The hypothesis was that delivering a vaccine to the colon would give different responses to orally administered antigen (antigen expected to be taken up by the small intestine) due to different immunological environments. Intramuscular and rectal deliveries were investigated as controls. Generally colonic administration gave levels of mucosal antibody (measured by IgA in faecal material) which were higher than those produced by oral or intramuscular delivery, and produced high levels of antibody on the vaginal mucosa. Following booster doses, colonic delivery also produced high levels of IgG in the serum which were similar to intramuscular levels. Subsequently, ways of delivering vaccines to the colon by oral administration were investigated. Amylose, which is degraded by colonic microbial enzymes, did not form microparticles except after exposure to high temperatures and was therefore unsuitable. Chitosan did form microparticles, and its digestion by human colonic bacteria was tested to determine its applicability for colon-specific targeting. Addition of the crosslinking agent tripolyphosphate to chitosan inhibited pancreatic (porcine) digestion but not human faecal digestion, and also reduced swelling which suggests its potential for colon-specific dosage forms in man. However, microparticles prepared from chitosan and tripolyphosphate were unable to control the release of a model drug (prednisolone) in low pH (stomach) conditions. Consequently, the exploitation of the changes in pH along the gastrointestinal tract was investigated for colonic targeting. Polymers were chosen which could be tested in rodents but the principle extrapolated to man. Hydroxypropylmethylcellulose phthalate polymers (dissolution threshold of pH 5 or 5.5) were identified as having potential for testing colonic-specific targeting of vaccines in the mouse. Vaccine nanoparticles, as used for immunisation, were successfully entrapped within the pH-responsive microparticles, and these nanoparticles can be released when pH 5 or 5.5 is reached. Further work is required to establish the in vivo release site of these microparticles, before orally administered colon-specific vaccination can be successfully tested.
... As a food, crickets contain all essential amino acids (Belluco et al., 2013), as well as minerals, vitamins, fatty acids (Rumpold & Schlüter, 2013), and fiber in the forms of chitin (4.3-7.1% of dry weight) and chitosan (2.4-5.8% of dry weight) (Ibitoye et al., 2018). Chitin is not digestible by dogs, but chitosan is (Okamoto et al., 2001), and to our knowledge its effects on the canine microbiome have not been studied. ...
Article
Full-text available
The gut microbiome plays an important role in the health of dogs. Both beneficial microbes and overall diversity can be modulated by diet. Fermentable sources of fiber in particular often increase the abundance of beneficial microbes. Banded crickets ( Gryllodes sigillatus ) contain the fermentable polysaccharides chitin and chitosan. In addition, crickets are an environmentally sustainable protein source. Considering crickets as a potential source of both novel protein and novel fiber for dogs, four diets ranging from 0% to 24% cricket content were fed to determine their effects on healthy dogs’ ( n = 32) gut microbiomes. Fecal samples were collected serially at 0, 14, and 29 days, and processed using high-throughput sequencing of 16S rRNA gene PCR amplicons. Microbiomes were generally very similar across all diets at both the phylum and genus level, and alpha and beta diversities did not differ between the various diets at 29 days. A total of 12 ASVs (amplicon sequence variants) from nine genera significantly changed in abundance following the addition of cricket, often in a dose-response fashion with increasing amounts of cricket. A net increase was observed in Catenibacterium , Lachnospiraceae [ Ruminococcus ], and Faecalitalea , whereas Bacteroides , Faecalibacterium , Lachnospiracaeae NK4A136 group and others decreased in abundance. Similar changes in Catenibacterium and Bacteroides have been associated with gut health benefits in other studies. However, the total magnitude of all changes was small and only a few specific taxa changed in abundance. Overall, we found that diets containing cricket supported the same level of gut microbiome diversity as a standard healthy balanced diet. These results support crickets as a potential healthy, novel food ingredient for dogs.
Article
Interest in use of the polysaccharide chitosan as a pharmaceutical excipient by different dose routes and for a number of applications is not new but it still does not appear to be present in any marketed drugs. Including a novel excipient in a new drug formulation requires a number of safety considerations. Review of the published literature showed that chitosan has low oral toxicity and local tolerance potential supporting use in non-parenteral formulations. Prior human oral exposure has occurred through use of chitosan dietary supplements and food additive, medical device and cosmetic applications. Although systemic exposure to parent chitosan may be limited (due to digestion in the gastrointestinal tract), any that is absorbed will likely undergo enzyme degradation to naturally occurring glucosamine, and N-acetylglucosamine, its copolymers, which are excreted or used in the amino sugar pool. Chitosan has local biological activity in the form of haemostatic action and, together with its ability to activate macrophages and cause cytokine stimulation (which has resulted in interest in medical device and wound healing applications), may result in a more careful assessment of its safety as a parenteral excipient.
Article
The lipid lowering activity of chitosan associated with Aloe vera L. or hydrosoluble chitosan with Brassica olearaceae L. has been studied in rats. In this study, rats were submitted to different treatments with hydrosoluble chitosan alone (4% diet), hydrosoluble chitosan associated with Aloe vera L. or hydrosoluble chitosan with Brassica olearaceae L. (1:4, 4% diet) for 35 days, to identify the formula with the highest hypolipaemic potential. The results showed that all treatments reduced blood lipid levels but that hydrosoluble chitosan associated with Brassica olearaceae L. proved most efficient, because it decreased the levels of total cholesterol, LDL-cholesterol, VLDL-cholesterol and triglycerides in blood serum. The overall results suggest that the hydrosoluble chitosan/Brassica olearaceae L. association is a therapeutic alternative for hyperlipidaemia, and in this way may contribute to the prevention of atherogenic processes.
Article
Three well-formed film combinations of chitosan, in the beta form and cellulose acetate biopolymer, having different proportions, have been synthesized and characterized by X-ray diffraction and infrared spectroscopy. The film having a 1.0/0.50 proportion presented 6.87 mmol of nitrogen atoms per gram of synthesized hybrid, with the highest affinity for adsorbing copper from aqueous solutions at 298+/-1K. The isotherm obtained in this adsorption showed a saturation plateau that corresponds to 1.92 mmol of copper per gram of hybrid. The energetic effects caused by copper ion interaction were determined through calorimetric titration at the solid-liquid interface in aqueous solution and gave a net thermal effect that enabled the calculation of the exothermic enthalpic values and the equilibrium constant. The complete thermodynamic data showed that the system is favored by exothermic enthalpies, negative Gibbs free energies and positive entropies.
Article
Thin films were prepared by the method of evaporation of aqueous solutions of chitosan or its mixtures with poloxamer 407, gelatin, or polyvinyl alcohol. Films of varying thickness were cross-linked with phosphate ions. They contained micronized folic acid in a concentration of 9.1% or 3.2%. Prolonged several hours' liberation of folic acid into isotonic phosphate buffer at pH 5.5, 6.0, and 6.5 was examined. In the initial stage, the mechanism of liberation was governed by diffusion of the dissolved fraction, at higher pH values a higher rate of dissolution of the substance played its role. In some composites, sorption of folic acid to chitosan in an extent dependent on the composition of composites and current acidity of the medium was demonstrated.
Article
Full-text available
The adsorption capacity of alpha-chitosan and its modified form with succinic anhydride was compared with the traditional adsorbent active carbon by using the dye methylene blue, employed in the textile industry. The isotherms for both biopolymers were classified as SSA systems in the Giles model, more specifically in L class and subgroup 3. The dye concentration in the supernatant in the adsorption assay was determined through electronic spectroscopy. By calorimetric titration thermodynamic data of the interaction between methyene blue and the chemically modified chitosan at the solid/liquid interface were obtained. The enthalpy of the dye/chitosan interaction gave 2.47 ? 0.02 kJ mol-1 with an equilibrium constant of 7350 ? 10 and for the carbon/dye interaction this constant gave 5951 ? 8. The spontaneity of these adsorptions are reflected by the free Gibbs energies of -22.1 ? 0.4 and -21.5 ? 0.2 kJ mol-1, respectively, found for these systems. This new adsorbent derived from a natural polysaccharide is as efficient as activated carbon. However 97% of the bonded dye can be eluted by sodium chloride solution, while this same operation elutes only 42% from carbon. Chitosan is efficient in dye removal with the additional advantage of being cheap, non-toxic, biocompatible and biodegradable.
Article
Full-text available
The present study evaluated the effects of chitosan nanoparticles (ChNPs) as a feed additive during the 1-42 days of age on growth performance, blood serum parameters, carcass traits, intestinal bacteria, digestive enzymes, and fat digestibility. Two hundred and forty of Japanese quail one day old were randomly distributed in four groups and fed a basal diet for 42 days. Groups 1, 2, 3, and 4 were fed 0.0 mg/kg diet (control group), 200 mg ordinary chitosan (OCh)/kg diet, 50 mg ChNP /kg diet and 200 mg ChNP /kg diet, respectively. The highest (P<0.05) final weight and weight gain were recorded in the group 4. Feed intake and mortality ratio were not affected significantly by ChNP supplementation. The best feed conversion ratio was recorded by the groups 2 and 4. Blood serum parameters were within the normal range; however, serum total triglyceride and malondialdehyde were increased significantly in the control group. The highest values for total lactobacillus and enterococcus count in the intestine were observed in the chitosan nanoparticles and chitosan groups. The coliforms count was significantly higher (P<0.05) in the control group and group 3 than in the other groups. Carcass weights in the groups 2 and 4 were significantly heavier (P<0.05) than in the other groups. However, abdominal fat weight was higher (P<0.05) in the control group than in the other groups. The lipase activity was decreased significantly (P<0.05) in the groups 2 and 4 compared to the control group. These results concluded that addition of chitosan nanoparticles had a positive effect on productive performance of Japanese quail.
Article
For the applications of polyelectrolyte complex (PEC) of chitosan and sodium cellulose sulfate (NaCS) as the controlled release drug carrier, the biodegradation characteristics of chitosan, NaCS and chitosan/NaCS PEC films were investigated with pepsin, trypsin, lipase, α-amylase, and cellulase. The results showed that pepsin, amylase, trypsin and lipase have the appreciable hydrolytic activity to chitosan, but cannot degrade NaCS. However, cellulase showed high cellulosic activity and low chitosanolytic activity. For the hydrolysis of chitosan/NaCS films, the degradation rates were greatly influenced by the molecular weights of chitosan and NaCS. In vitro tests showed that different formulations caused diverse disintegration time of the films through the gastrointestinal tract. The results indicated the PEC based on chitosan and NaCS showed good potential for the gastrointestinal delivery systems.
Chapter
IntroductionDietary Fiber IntakeTypes of Dietary FiberStructure and sourcesInfluence of Dietary Fiber on the Upper Gastrointestinal TractInfluence of Dietary Fiber on the Lower Gastrointestinal TractEffect of Dietary Fiber on Colonic DiseasesConclusions References
The prophylactic effect of crustacean chitosan (CC) against malarial infection was examined in BALB/c mice. CC dissolved in 0.5% acetic acid at different concentrations was given either intraperitoneally (i.p.) or orally from day 0 to day 5. Mice which received 0.5% acetic acid were used as the negative control whereas mice treated with chloroquine diphosphate were served as the positive control. All mice were infected with parasitized red blood cells on day 4. Our results showed that CC treatment, either administered intraperitoneally or orally, possessed prophylactic effects on blood induced infection of P. berghei. All CC-treated mice exhibited longer life-span when compared to control mice received only vehicle. However, CC treatment intraperitoneally gave stronger protection where a dosage at 250 mg/kg showed significant parasite suppression as well as longer survival time of the infected mice. CC treatment through i.p. route also caused significantly higher neutrophil counts in the peripheral blood. We suggest that the activation of neutrophils in peripheral blood through prophylactic activity of CC may play a crucial role in the antimalarial activity of the host.
Article
Cellulose has been discovered as a smart material, which is termed as electro-active paper (EAPap). EAPap actuator revealed large displacement upon low actuation voltage and low electrical power consumption. However, the performance of the actuator was reduced as the actuation time increased. To investigate the performance degradation of the actuator, field emission scanning electron microscope (FESEM) images were taken on the surfaces of gold electrode of the actuator, and energy dispersive spectroscopy (EDS) was performed on them. Nanoparticles and nanoholes were observed on the surfaces of gold electrode after actuation, which might be strongly associated with the degradation of the actuator performance. The compositions of nanoparticles were gold and sodium. The degradation rate of the actuator performance and the number of nanoparticles at a low actuation frequency (2 Hz) were larger than those of a higher frequency (5 Hz). As the actuation voltage increased, the actuator performance degraded rapidly.
Preprint
Full-text available
The gut microbiome plays an important role in the health of dogs. Both beneficial microbes and overall diversity can be modulated by diet. Fermentable sources of fiber in particular often increase the abundance of beneficial microbes. House crickets ( Acheta domesticus ) contain the fermentable polysaccharides chitin and chitosan. In addition, crickets are an environmentally sustainable protein source. Considering crickets as a potential source of both novel protein and novel fiber for dogs, 4 diets ranging from 0% to 24% cricket content were fed to determine their effects on healthy dogs’ (n = 32) gut microbiomes. Fecal samples were collected serially at 0, 14, and 29 days, and processed using high-throughput sequencing of 16S rRNA gene PCR amplicons. Microbiomes were generally very similar across all diets at both the phylum and genus level, and alpha and beta diversities did not differ between the various diets at 29 days. A total of 12 ASVs (amplicon sequence variants) from nine genera significantly changed in abundance following the addition of cricket, often in a dose-response fashion with increasing amounts of cricket. A net increase was observed in Catenibacterium , Lachnospiraceae [ Ruminococcus ], and Faecalitalea , whereas Bacteroides , Faecalibacterium , Lachnospiracaeae NK4A136 group and others decreased in abundance. The changes in Catenibacterium and Bacteroides are predicted to be beneficial to gut health. However, the total magnitude of all changes was small and only a few specific taxa changed in abundance. Overall, we found that diets containing cricket supported the same level of gut microbiome diversity as a standard healthy balanced diet. These results support crickets as a potential healthy, novel food ingredient for dogs.
Article
DNA-chitosan bilayer membranes were designed and prepared as a biomedical adhesive for therapeutic application. Various DNA-chitosan bilayer membranes were prepared by applying chitosan solution (2.0 mg cm-2) on UV-irradiated DNA membranes (0.2–0.5 mg cm-2). Tensile strengths of the DNA-chitosan bilayer membranes were approximately 4.0 N similar to that of chitosan alone membrane 2.0 mg cm-2. These results indicate that the bilayer membranes have enough tensile strength as a surgical tape. When the surface of the DNA-chitosan membranes was analyzed using a scanning electron microscope (SEM), fiber-like structure was observed on the DNA-side of the DNA-chitosan membranes, prepared from more than 0.3 mg cm-2 of UV-irradiated DNA membranes. In contrast, the chitosan-side of the DNA-chitosan membranes showed a smooth surface similar to that of the chitosan alone membrane. These results indicated that a DNA-chitosan bilayer membrane was successfully prepared using UV-irradiated DNA membranes (0.3–0.5 mg cm-2) and chitosan (2.0 mg cm-2). Next, we observed bonding strength of the membranes to rabbit peritoneum. The bonding strength of the chitosan-side was similar to that of fibrin glue. On the other hand, DNA side of bilayer membrane did not adhere to the peritoneum. The DNA-chitosan membrane is bi-functional and has a potential to serve as a bi-functional bio-adhesive.
Conference Paper
The suitability of chitosan (non-crosslinked and crosslinked by glutaraldehyde) for colonic drug delivery was assessed by incubation of chitosan films in human faecal slurry and assessment of the film’s disappearance with time. It was found that non-crosslinked chitosan, was digested by colonic bacteria, but crosslinked chitosan was not.
Article
Full-text available
The suitability of chitosan (non-crosslinked and crosslinked by glutaraldehyde) for colonic drug delivery was assessed by incubation of chitosan films in human faecal slurry and assessment of the film's disappearance with time. It was found that non-crosslinked chitosan, was digested by colonic bacteria, but crosslinked chitosan was not. Introduction: Polysaccharides, such as amylose, guar gum, pectin and chitosan (Basit, 2005) are increasingly being investigated for the delivery of drugs to the colon. An essential feature of these potential drug delivery systems is non-degradation by small intestinal digestive enzymes, but digestion by the enzymes produced by the colonic microflora. Thus, they should prevent drug release in the small intestine, and allow drug release in the colon. Chitosan is being investigated as it is biodegradable, biocompatible and has low oral toxicity. There are several investigations into the suitability of chitosan for colonic delivery (Tozaki et al., 1997; Zambito et al., 2005) but all investigations to date have used rat caecal contents to assess the colonic release. This may not be directly comparable to human colonic contents or faecal material. Work has shown that chitosan is degraded to different extents in different species, such as dogs (Okamoto et al., 2001), rabbits, hens and sheep (Hirano et al., 1990). Hence, it cannot be assumed that chitosan is sufficiently digested by human colonic microflora. Before investigating the potential of chitosan as a colonic delivery system, it is essential to assess whether the human colonic microflora is capable of digesting the material. The process of microfloral digestion is one of fermentation, in which the anaerobic bacteria break down substrates to produce energy. Chitosan, a weak base (pKa 6.2-7.0), is a [(1,4) 2 amino-2-deoxy-beta-d-glucan], whose structure is shown in Figure 1. It is obtained by the alkaline deacetylation of chitin, which is the second most abundant polysaccharide in nature, after cellulose. It is found in the exoskeletons of crustaceans and insects which are not substantial components of the human diet. Human colonic bacteria may not therefore normally produce enzymes capable of digesting chitin and chitosan. The latter is structurally similar to cellulose, which has been shown not to be fermented in the human colon.
Chapter
The development of drug delivery systems always goes hand in hand with the advancement of material science. The novel synthetic or natural functional materials provide opportunities to design optimal drug delivery systems. Among these, chitosan and its derivatives exhibit excellent application future because of its prominent characteristics. In this chapter, research progress of chitosan and its derivatives for drug delivery, from structure to properties, from properties to its application were overviewed. The physicochemical properties, biological properties, biodegradability, safety evaluation and structure modification of chitosan were introduced. Furthermore, applications of chitosan and its derivatives in drug delivery including as the carrier of nanoparticles and microparticles, as coating material, as matrix of hydrogels, films and sustained release tablets, as stabilizers, as absorption enhancers, were discussed. Finally, the applications of chitosan and its derivatives in different administration routes, and their advantages for gene, protein and vaccine delivery, were reviewed. The numerous successful studies on exploitation and application of chitosan and its derivatives showed promising application future of these materials in drug delivery.
Chapter
Chitin is the main constituent of crustacean exoskeletons. Traditional chemical processes for its recovery create a disposal problem, due to the large amounts of toxic waste produced. This chapter reviews the current methods of obtaining chitin, chitosan, and chitooligosaccharides and describes alternatives, such as the use of proteolytic enzymes, fermentation with selected microorganisms, ultrasonication and microwave treatment, and the use of ionic liquids. Methods for obtaining chitosan based on alkaline or enzymatic deacetylation of chitin and strategies for increasing its solubility in water, such as hydrolysis of the glycosidic bonds in chitosan-releasing chitooligosaccharides or the formation of different types of chitosan derivative, are also given. Chitosan's biological activities, such as antioxidant, hypocholesterolemic, antimicrobial, antihypertensive, prebiotic, and ion-binding activities, are presented, as are its potential applications in food, medicine, pharmacy, agriculture, and cosmetics.
Article
This study provides experimental evidence to determine if cooked (heat-treated at 180 °C) or uncooked bones solubilise in vitro at different rates and if cooking alters the bone's physical properties. In vitro testing of the solubilisation and mechanical properties of cooked and uncooked porcine ribs was performed after incubating the bones in artificial gastric juice. The resistance of the bone to penetration by a pin used to simulate tooth-penetration was measured using a tensometer. Results demonstrated that cooked bone was significantly more soluble in artificial gastric juice and required significantly less energy for breakage by pin penetration than uncooked bone.This study showed that in vitro, cooked bone is digested faster and requires less energy for pin penetration.
Article
Chitosan salts are being investigated as materials for bacterially triggered colonic drug delivery, via the oral route, based on the assumption that they will be degraded by the enzymes produced by the human colonic bacteria. The actual susceptibility of chitosan to these enzymes is, however, unclear. The digestion of chitosan films (noncrosslinked, and crosslinked with glutaraldehyde or tripolyphosphate) by human colonic bacteria (using human faecal material) was therefore investigated, and in addition, their digestion by pancreatic enzymes (of porcine origin) was assessed. Noncrosslinked chitosan films were digested by both pancreatic and colonic enzymes within 4 h, while glutaraldehyde crosslinked chitosan films were resistant to both enzyme systems. In contrast, tripolyphosphate crosslinked chitosan films resisted pancreatic digestion, but were susceptible to faecal digestion over the same 4 h time period. As expected, lowering crosslinker concentration and increasing incubation time (to 18 h) allowed greater digestion. The difference between the crosslinkers is attributed to the mechanism of crosslinking, and the associated degree of film swelling in an aqueous environment. Swelling studies in acidic conditions suggest that only glutaraldehyde or higher concentrations of tripolyphosphate would be able to prevent film dissolution in gastric conditions.
Article
Full-text available
A series of experiments with male rats clearly demonstrated the hypocholesterolemic activity of dietary chitosan. On feeding a high cholesterol diet for 20 days, addition of 2 to 5% chitosan resulted in a significant reduction, by 25 to 30%, of plasma cholesterol without influencing food intake and growth. The concentration of liver cholesterol and triglyceride also decreased significantly. Plasma, but not liver cholesterol-lowering effect, was roughly comparable with that of cholestyramine. Chitosan at the 10% level further reduced plasma cholesterol, but depressed growth. Also, finer chitosan particles tended to restrain growth even at the 2% level. In rats fed a cholesterol-free diet containing 0.5% chitosan for 81 days, the concentration of serum cholesterol was the same with that of the corresponding control, but relatively more cholesterol existed as high-density lipiproteins and less as very low-density lipoproteins. Dietary chitosan increased fecal excretion of cholesterol, both exogenous and endogenous, while that of bile acids remained unchanged. There was no constipation or diarrhea. A proper supplementation of chitosan to the diet seemed to be effective in lowering plasma cholesterol.
Article
Full-text available
Various acetylated chitosan derivatives and mixtures of chitin and chitosan, covering the range of the degree of deacetylation (DDA) from 0-100% were analyzed by 1H-NMR spectroscopy and infrared spectroscopy. The use of the 1070 cm-1 or 1030 cm-1 absorption band as an internal standard in the determination of DDA from the absorbance of the amide I bands at 1655 cm-1 and 1630 cm-1 or the amide II band at 1560 cm-1 was studied. There is a good correlation between the results from IR spectroscopy and those from 1H-NMR spectroscopy.
Article
The present study is the first to report the hypocholesterolemic effect of chitosan on humans. When 3–6 g/day of chitosan was given in the diet to 8 healthy males, total serum cholesterol significantly decreased, and when the ingestion was stopped, the value increased to the level before ingestion. Serum HDL-cholesterol was increased significantly by the ingestion of chitosan. The excreted amounts of primary bile acids, cholic acid and chenodeoxycholic acid, into the feces was significantly increased by the ingestion of chitosan, and the amount of cholic acid excretion decreased significantly after the ingestion was stopped. These facts suggest that chitosan combined bile acids in the digestive tract, and that the combined product was excreted into the feces. This, in turn, deceased the resorption of bile acids, so that the cholesterol poool in the body was decreased and the level of serum chrolesterol consequently decreased.
Article
Chitosan was tested for use as an ingredient for domestic animal feeds. (1) No abnormal symptom was observed with hens and broilers by feeding <1.4 g of chitosan/kg of body weight per day for up to 239 days, and with rabbits by feeding <0.8 g of chitosan/kg of body weight per day for up to 239 days. (2) Both chitin and chitosan were digested 35-83% by rabbits and 88-98% by hens and broilers. (3) An increase in the serum cholesterol, triacylglycerol, and free fatty acid values of these domestic animals fed cholesterol-additive diets was suppressed by feeding 1.2-1.4 g of chitosan/kg of body weight per day for hens and broilers and 0.7-0.8 g of chitosan/kg of body weight per day for rabbits, but not by feeding chitin. (4) Hen's appetite and egg-laying rate decreased by feeding an excessive amount of chitosan for a long term (3.6-4.2 g of chitosan/kg of body weight per day for 189 days) because of incomplete digestion of chitosan.
Article
In rabbits fed a 0.9% cholesterol-enriched (to 9 g kg−1) and 20 g kg−1 chitosan-supplemented diet, total faecal bile acid and sterol levels increased 1.2-1.4 times (cholic acid 5.0 times, and cholesterol 1.5 times) those in rabbits fed a cholesterol-enriched (to 9g kg−1) diet. The serum cholesterol and triacylgiycerol levels of high-serum-cholesterol rabbits were affected neither by feeding with a 20 g kg−1 chitosan-supplemented diet nor by intravenous injection with chitosan of low molecular weight (c3000) or chitosan oligosaccharides (300-1162) daily. These data indicate that chitosan plays a hypocholesterolaemic action only in the intestine.
Article
The lipid binding capacity of chitosan (partially deacetylated chitin) was determinined with respect to micellar solutions of bile salts, dodecyl sulfate, natural ox bile and an artificial mixed microemulsion. The stoichiometry was determined following the separation of the solid phase by filtration or centrifugation. The major variables in the extent of binding were the pH and ionic strength, suggesting that the interactions are mainly of ionic nature. It is noteworthy that under optimal conditions chitosan could bind, i.e., coprecipitate, with 4–5 times of its weight with all the lipid aggregates tested. These results have a bearing on the nutritional and pharmacological applications of chitosan. The analyses of the components from the precipitates with microemulsion and ox bile show a significant selectivily of binding caused by hydrophobic interactions.
Article
The effect of chitin at the level of 5% in the diet on cholesterol absorption and metabolism was studied in Wistar rats fed on diet containing beef tallow (7%) and cholesterol (1%). When compared with pair-fed controls, rats fed on diet containing chitin had: (1) similar weight gain and feed efficiency, (2) lower apparent protein digestibility, (3) equivalent liver steatosis, (4) reduced levels of liver triglycerides and cholesterol, (5) similar levels of serum and fecal cholesterol, (6) higher excretion of triglycerides in feces.
Article
The effect of chitosan feeding (for 21 days) on intestinal bile acids was studied in male rats. Serum cholesterol levels in rats fed a commercial diet low in cholesterol were decreased by chitosan supplementation. Chitosan inhibited the transformation of cholesterol to coprostanol without causing a qualitative change in fecal excretion of these neutral sterols. Increased fiber consumption did not increase fecal excretion of bile acids, but caused a marked change in fecal bile acid composition. Lithocholic acid increased significantly, deoxycholic acid increased to a lesser extent, whereas hyodeoxycholic acid and the 6 beta-isomer and 5-epimeric 3 alpha-hydroxy-6-keto-cholanoic acid(s) decreased. The pH in the cecum and colon became elevated by chitosan feeding which affected the conversion of primary bile acids to secondary bile acids in the large intestine. In the cecum, chitosan feeding increased the concentration of alpha-,beta-, and omega-muricholic acids, and lithocholic acid. However, the levels of hyodeoxycholic acid and its 6 beta-isomer, of monohydroxy-monoketo-cholanoic acids, and of 3 alpha, 6 xi, 7 xi-trihydroxy-cholanoic acid decreased. The data suggest that chitosan feeding affects the metabolism of intestinal bile acids in rats.
Article
The relationship between hypocholesterolemic efficacy and average molecular weight of chitosan was studied in rats fed a cholesterol-enriched (0.5%) diet. Several chitosan preparations with a comparable degree of deacetylation but differing widely in average molecular weight, as demonstrated by viscosity, almost completely prevented the rise of serum cholesterol at the 5% dietary level. At the 2% level, chitosans with viscosities at both extremes exerted a comparable cholesterol-lowering action. The glucosamine oligomer composed mainly of three to five aminosugar residues was not effective. The results indicate that the hypocholesterolemic action of chitosans is independent of their molecular weight within the tested viscosity range.
Article
The effects of chitosan and cholestyramine on intestinal absorption of oleic acid and cholesterol were assessed in adult male rats with cannulae in the thoracic duct lymphatic channel. In acute studies, 50 mg of either cholestyramine or chitosan were included in the test emulsion for intragastric administration. Over a 24-h lymph collection period, cholestyramine caused a 47% depression of cholesterol absorption and a 32% interference with oleic acid absorption. Chitosan had a similar effect on the absorption of both lipids under these conditions (51 and 41% depression, respectively). Studies were also conducted in animals fed for 4 wk on defined diets containing 1 and 5% levels of the test materials. Absorption of lipids from the standard aqueous emulsion was tested in lymph duct cannulated rats which had been fasted overnight. In these animals, prefeeding either cholestyramine or chitosan at the 1% level caused an 18 to 28% reduction in absorption of both lipids with greater variability in the chitosan-fed group. When either test material was fed at the 5% level, absorption of cholesterol was reduced by 63 to 69% and absorption of oleic acid by 58 to 62%. Although these agents may act by different mechanisms, the data suggest that chitosan is as effective as cholestyramine in its acute effects on lipid absorption and that, with chronic feeding, both materials cause equivalent adaptive changes in intestinal transport of administered fatty acid and cholesterol.
Article
We investigated the mechanism for the inhibition of fat digestion by chitosan, and the synergistic effect of ascorbate. The important inhibition characteristics of fat digestion by chitosan from observations of the ileal contents were that it dissolved in the stomach and then changed to a gelled form, entrapping fat in the intestine. The synergistic effect of ascorbate (AsA) on the inhibition of fat digestion by chitosan is thought not to be acid-dependent but due to the specificity of AsA itself, according to the data resulting from using preparations supplemented with sodium ascorbate (AsN). The mechanism for the synergistic effect is considered to be 1) viscosity reduction in the stomach, which implies that chitosan mixed with a lipid is better than chitosan alone, 2) an increase in the oil-holding capacity of the chitosan gel, and 3) the chitosan-fat gel being more flexible and less likely to leak entrapped fat in the intestinal tract.
A study on the degradability of chitin and chitosan in the rumen of sheep given Italian ryegrass hay ad libitum
  • Y Yoshino
  • A Matsuhashi
  • S Minami
  • Y Okamoto
  • Y Shigemasa
  • R Oura
  • J Sekine
Yoshino, Y., Matsuhashi, A., Minami, S., Okamoto, Y., Shigemasa, Y., Oura, R., & Sekine, J. (1991). A study on the degradability of chitin and chitosan in the rumen of sheep given Italian ryegrass hay ad libitum. Journal of the Faculty of Agriculture, Tottori University, 27, 47±51.
Specification and characterization of chitin and chitosan
  • Tokura
Tokura, S., & Nishi, N. (1995). Speci®cation and characterization of chitin and chitosan. In Mat. B. Zaria, Wan Mohamed Wan Muda & Md. Paudi Abdullah, Chitin and chitosan (pp. 67±86). Malaysia: Penerbit Univer-siti Kebangsaan.
Mechanism for the inhibition of fat digestion by chitosan and for the synergistic effect of ascorbate Hypocho-lesterolemic effect of chitosan in adult males The binding of micellar lipids to chitosan Intestinal absorption of 14 C-chitosan in rats Evalua-tion of different absorbance ratios from
  • O Kanauchi
  • K Deuchi
  • Y Imasato
  • M Shizukuishi
  • E Kobayashi
  • ±790 Maezaki
  • Y Tsuji
  • K Nakagawa
  • Y Kawai
  • Y Akimoto
  • M Tsugita
  • T Takekawa
  • W Terada
  • A Hara
  • H Mitsuoka
  • ±1444 Nauss
  • J L Thompson
  • J L Nagyvary
  • J J Takeda
  • H Wada
  • M Yukawa
Kanauchi, O., Deuchi, K., Imasato, Y., Shizukuishi, M., & Kobayashi, E. (1995). Mechanism for the inhibition of fat digestion by chitosan and for the synergistic effect of ascorbate. Bioscience, Biotechnology and Biochemistry, 59, 786±790. Maezaki, Y., Tsuji, K., Nakagawa, Y., Kawai, Y., Akimoto, M., Tsugita, T., Takekawa, W., Terada, A., Hara, H., & Mitsuoka, T. (1993). Hypocho-lesterolemic effect of chitosan in adult males. Bioscience, Biotechnol-ogy and Biochemistry, 57, 1439±1444. Nauss, J. L., Thompson, J. L., & Nagyvary, J. J. (1983). The binding of micellar lipids to chitosan. Lipids, 18, 714±719. Nishimura, Y., Watanabe, Y., Hong, J. M., Takeda, H., Wada, M., & Yukawa, M. (1997). Intestinal absorption of 14 C-chitosan in rats. Chitin Chitosan Research, 3, 55±61. Shigemasa, Y., Matsuura, H., Sashiwa, H., & Saimoto, H. (1996). Evalua-tion of different absorbance ratios from infrared spectroscopy for analyzing the degree of deacetylation in chitin. International Journal of Biological Macromolecules, 18, 237±242.
Intestinal absorption of 14C-chitosan in rats
  • Nishimura
A study on the degradability of chitin and chitosan in the rumen of sheep given Italian ryegrass hay ad libitum
  • Yoshino