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Comparing the Effects of Collagen Hydrolysate and Dairy Protein on Recovery from Eccentric Exercise: A Double Blind, Placebo-Controlled Study.
(MDPI (Basel, Switzerland), 2024-12-20) Barclay R; Coad J; Schraders K; Barnes MJ; Driss T
Background: Consuming collagen hydrolysate (CH) may improve symptoms of exercise-induced muscle damage (EIMD); however, its acute effects have not been compared to dairy protein (DP), the most commonly consumed form of protein supplement. Therefore, this study compared the effects of CH and DP on recovery from EIMD. Methods: Thirty-three males consumed either CH (n = 11) or DP (n = 11), containing 25 g of protein, or an isoenergetic placebo (n = 11) immediately post-exercise and once daily for three days. Indices of EIMD were measured before and 30 min and 24, 48, and 72 h after 30 min of downhill running on a −15% slope at 80% of VO2max speed. Results: Downhill running induced significant EIMD, with time effects (all p < 0.001) for the delayed onset of muscle soreness (visual analogue scale), countermovement jump height, isometric midthigh pull force, maximal voluntary isometric contraction force, running economy, and biomarkers of muscle damage (creatine kinase) and inflammation (interleukin-6, high-sensitivity C-reactive protein). However, no group or interaction effects (all p > 0.05) were observed for any of the outcome measures. Conclusions: These findings suggest that the post-exercise consumption of CH or DP does not improve indices of EIMD during the acute recovery period in recreationally active males.
Pilot study on the effects of preservatives on corneal collagen parameters measured by small angle X-ray scattering analysis
(BioMed Central Ltd, 2021-12) Kelly SJ; duPlessis L; Soley J; Noble F; Wells HC; Kelly PJ
OBJECTIVE: Small angle X-ray scattering (SAXS) analysis is a sensitive way of determining the ultrastructure of collagen in tissues. Little is known about how parameters measured by SAXS are affected by preservatives commonly used to prevent autolysis. We determined the effects of formalin, glutaraldehyde, Triton X and saline on measurements of fibril diameter, fibril diameter distribution, and D-spacing of corneal collagen using SAXS analysis. RESULTS: Compared to sections of sheep and cats' corneas stored frozen as controls, those preserved in 5% glutaraldehyde and 10% formalin had significantly larger mean collagen fibril diameters, increased fibril diameter distribution and decreased D-spacing. Sections of corneas preserved in Triton X had significantly increased collagen fibril diameters and decreased fibril diameter distribution. Those preserved in 0.9% saline had significantly increased mean collagen fibril diameters and decreased diameter distributions. Subjectively, the corneas preserved in 5% glutaraldehyde and 10% formalin maintained their transparency but those in Triton X and 0.9% saline became opaque. Subjective morphological assessment of transmission electron microscope images of corneas supported the SAXS data. Workers using SAXS analysis to characterize collagen should be alerted to changes that can be introduced by common preservatives in which their samples may have been stored.
Commercially scalable fish collagen processing : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, Palmerston North, New Zealand
(Massey University, 2023) Gonapinuwala, Suchima Tharangi
Fish collagen has a potential for high-value applications in the biomedical industry due to its excellent biocompatibility, biodegradability and low antigenicity properties. It is also a viable alternative for mammalian collagen due to its high availability, having no risk of disease transmission or religious barriers and the low cost of raw material. However, its utilisation is limited due to the non-availability of industrial-scale processing methods. Maintaining the native triple-helical structure in collagen molecules and the native D-banding pattern in the collagen fibrils are the requisites for biomedical collagen, therefore the existing industrial fish collagen extraction methods for food or cosmetic applications cannot be used. Unlike mammalian-origin collagen, fish-origin collagen differs due to fish species differences, and it is not practical to develop by trial and error, collagen extraction methods for every individual fish species of interest. Therefore, this study was carried out to interpret how the fish skin structure and composition relate to the physico-chemical processes that occur during collagen extraction, to develop a biomedical collagen extraction method based on this understanding, and to present guidelines to use this method for other fish species at industrial-scale. This collagen extraction process was developed through three main steps: pretreatment, extraction, and fibrillogenesis, and important determinants at each step, in relation to the fish skin structure and composition were identified. The focus of the pretreatment step is to remove non-collagenous proteins and fats, and the swelling of the skin in the pretreatment medium was also found to be a critical aspect in this tissue due to the structure of fish skin. The focus of the extraction step is to solubilise collagen molecules into the extraction medium in its native triple-helical conformation. Using a hydrochloric acid medium at an initial pH of 2 was found to be important in preserving the native triple-helical structure of collagen molecules. In addition, four processing objectives were presented based on the underpinning knowledge, to apply this method to any fish species of interest: (i) an upper limit of pH 4 for the extraction solution; (ii) maximum swelling; (iii) a manageable viscosity of the extraction solution; and (iv) as few undissolved pieces of skin as possible. A second extraction was introduced as a pigment removal step to improve the purity and colour of collagen while still preserving the collagen native structure. The ultimate focus of the whole collagen extraction process is the formation of collagen fibrils with the native D-banding pattern, which is achieved in the fibrillogenesis step. An initial collagen concentration of 0.30% in 0.01 M hydrochloric acid solution, adding 0.1 M Sodium hydroxide until pH 9.3 with gentle mixing, and keeping undisturbed for 24 h at 4°C are recommended as processing conditions to obtain collagen fibrils with native D-banding pattern. The initial collagen concentration is critical for molecular availability and the mixing speed is critical for molecular mobility during fibrillogenesis. With this understanding of the behaviour of fish skin during the extraction process, and the knowledge on how it can be applied to any fish species of interest, the future processing of biomedical collagen from fish skin at the industrial level will be possible.
Novel collagen-based wafers as a drug delivery method for local analgesia in deer antlers : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Sciences at Massey University, Manawatu, New Zealand
(Massey University, 2021) Sahebjam, Farzin
Introduction This study provided a practical and novel solution for post-operative pain mitigation and wound management after velvet antler removal in red deer (Cervus elaphus). Currently, there are no topical methods to mitigate pain for an extended period of time in deer following surgical removal of antlers. The current methods licensed in New Zealand provide only peri-operative analgesia with short-term effects and raise animal welfare concerns about whether animals are still in pain when the effect has worn off, especially in the deer industry in which a large number of animals are being managed. Materials and methods In vitro study: In vitro drug release test (IVDRT) was conducted using the Franz diffusion cell to assess the drug release rates of lidocaine and bupivacaine in two different phases of the pilot and main studies. The pilot in vitro study contained 9 treatment groups and 3 control groups (n=3), which were classified based on collagen extraction technique, whether modified with zinc oxide-polyvinylpyrrolidone (ZnO-PVP) nanoparticles and the difference in the order of adding local anaesthetics and ZnO-PVP nanoparticles. The main in vitro study was comprised of 4 treatment groups of 5%, 10%, and 25% ZnO-PVP nanoparticles (n=6) proportional to dry collagen weight and a control group. In both pilot and main in vitro studies, the samples were taken every 15 minutes in the first hour and every 2 hours up to 12 hours. LC-MS and HPLC were used for the quantification of the samples in the pilot and main in vitro studies, respectively. MNT validation study: Forty male deer (stags) were assigned for the MNT validation study on three alternative days. A handheld algometer (Wagner FPX50) was used for mechanical nociceptive threshold (MNT) assessment of four antler sites (cranial, medial, caudal, lateral) in both right and left antlers. Animal body weight (kg) and antler length (cm) were recorded to investigate the correlation with MNT. The MNT readings from three days were compared with each other. In addition, the MNT reading from all four antler sites and the right and left antlers were compared with each other. In vivo study: Eighteen stags sorted into three groups of 6 animals in each (2 treatment groups and 1 control group) for the pilot in vivo study, and forty yearling age stags assorted into four groups of 10 animals (three treatments and one control), were used in the main in vivo study. All animals had both antlers removed after administration of local anaesthesia. The control group in both pilot and main in vivo studies received a ring block of 4% articaine hydrochloride only, whilst the treatment groups received modified (with ZnO-PVP) or non-modified collagen composite wafers to the wound sites. The modified collagen composite wafers had 50% ZnO-PVP for the pilot in vivo study and had 0%, 5% or 25% ZnO-PVP proportional to dry collagen weight for the main in vivo study. A handheld algometer (Wagner FPX50), was used for mechanical nociceptive threshold (MNT) assessment at different time points (0, 4, 24, 72 hrs, 7 days and 14 days). Thermal imaging with a forward-looking infrared (FLIR) camera was performed for the detection of temperature differences between the groups. Digital photography of the wounds was performed for further quantitative wound healing analysis. Pharmacokinetic study: Blood samples were drawn from deer after the application of collagen composite wafers at time points t0, t1, t2, t4, t6, t8, t12, and t24 hours for the pilot study and at time points t0, t1, t2, t4, t6, t8, and t24 hours for the main in vivo study. The plasma was iv analysed with LC-MS to calculate pharmacokinetic parameters with the non-compartmental method such as Cmax, Tmax, AUC, AUMC, half-life, the volume of distribution and clearance. Statistical analysis: Higuchi model was mainly incorporated to calculate drug release rates for the in vitro studies. For in vivo studies, the statistical analyses were performed with a linear model for repeated measurements that accounted for the fixed effects of day, antler, location within antler or antler sites, antler length and weight of deer as covariates, and the random effect of animals. Results IVDRT did not show any statistically significant difference between the treatment groups; however, the treatment groups had significantly slower release compared to the control group in the pilot in vitro study. IVDRT in the main in vitro study showed the slowest release rate in the treatment group with 25% ZnO-PVP compared to the other groups for both lidocaine and bupivacaine. The control group had the most rapid drug release rates compared to the treatment groups, particularly for lidocaine. Furthermore, lidocaine showed a considerably slower release compared to bupivacaine when zinc oxide nanoparticles were incorporated, and the results significantly differed. MNT validation results showed that antler length (cm) and animal body weight (kg) are directly and positively correlated with the baseline MNT readings. The MNT readings from four sites of antlers, including cranial, medial, caudal and lateral aspects, did not have any significant difference from each other. In addition, the MNT readings from the right and left antlers did not show any significant difference from each other. In vivo results in the pilot study showed a lack of collagen composite wafer adherence for the non-modified wafers (PT2) and 50% adherence for the modified wafers (PT1) in the pilot study. As a result of the main in vivo study, 90%, 70%, and 45% were in group 25%NP (T1), 5%NP (T2), and 0%NP (T3) to the wounds, respectively. A significant difference was observed in the recovery rates of PT1 compared to the control group (P<0.0001) for the pilot study. For the main in vivo study, all three treatment groups also showed a significant difference compared to each other: T1 vs. T2 (P<0.01), T1 vs. T3 (P<0.05), and T2 vs. T3 (P<0.0001). In addition, the treatment groups showed a significantly slower recovery rate from analgesia compared to the control group (P<0.0001 for all). All the treatment groups in the main study demonstrated analgesia beyond 6 hrs and up to 10 hrs. The pharmacokinetics study showed significantly smaller Cmax for T1 and T2 compared to T3 only for bupivacaine. Tmax showed significantly smaller values for T1 compared to T2 for only bupivacaine. Both AUC (0-24), AUC (0-∞), and AUMC (0-∞) showed smaller values for T1 and T2 compared to T3. Conclusion The physically modified collagen composite wafer with zinc oxide-PVP nanoparticles, containing a short-acting (lidocaine) and a long-acting (bupivacaine) local anaesthetic, is a novel method to sustain drug delivery of local anaesthetics after the surgical removal of velvet antlers. Our suggested treatment can deliver analgesia to the wounded antler for up to 10 hours and is a safe and convenient method to use by farmers in the deer industry. Furthermore, the collagen wafer is very adhesive to the wound and can help facilitate wound healing of deer antlers.
Assessment of the effects of dietary fibre and animal-derived fermentable substrates on the gastrointestinal microbiome and associated faecal parameters of the domestic cat (Felis catus) : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science at Massey University, Palmerston North, New Zealand
(Massey University, 2021) Butowski, Christina Frances
Globally, commercial diets high in animal protein and fat are becoming increasingly popular for pets. However, there is little research assessing the impacts of such diets in domestic cats. Dietary fibre and animal-derived fermentable substrates (ADFS) are of interest because of their role in gastrointestinal health. A series of in vivo and in vitro studies were conducted to determine the effects of ADFS on the food-host-microbiome interaction in the domestic cat. Initially, the impact of dietary fibre inclusion in a high protein raw meat diet on the faecal microbiome was determined (Chapter Two). Observations from this study suggested that a high protein raw meat diet was highly digestible and influenced the frequency of defecation in the domestic cat. As part of this study, I also assessed two methodologies. Firstly, the point at which the faecal microbiome should be sampled after diet adaption (Chapter Three) and secondly, the suitability of a rectal swab sample (Chapter Four) in determining the composition of the faecal microbiome. I ascertained that the faecal microbiome of the cat could ferment dietary fibre (inulin and cellulose). Furthermore, relative stability of the microbiome was reached after day 5. However, rectal swab samples did not replicate the taxonomic complexity of the faecal microbiome. Based on results from Chapter Two, I assessed the fermentative capacity of a range of ADFS compared to dietary fibre in vitro (Chapter Five). I found that hydrolysed collagen produced the greatest concentrations of butyrate in this system. Therefore, in the final study, I assessed the impacts of hydrolysed collagen inclusion in a high protein raw meat diet on the faecal metagenome (Chapter Six). Additionally, I assessed tryptophan metabolites as they include a key neurotransmitter, serotonin, which has local effects on the colon and may explain the differences in defecation frequency observed. I found that the hydrolysed collagen was fermented by the gastrointestinal microbiome of the domestic cat and could have the potential to replace dietary fibre in the diet of the domestic cat. From this, future research could verify the potential of ADFS in replacing dietary fibre in domestic cats. In addition, further work is required in determining the functional potential of the microbiome of the domestic cat to fully understand the impact of diet on the host-microbiome interactions.
Unravelling the molecular contributions to collagen higher order structure : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Biochemistry at Massey University, Manawatu, New Zealand
(Massey University, 2019) Visser, Danielle Renee
Abnormal levels of cross-linking in fibrillar collagen strands have been shown to cause a number of human and animal diseases. Cross-linking is a vital step in fibrillogenesis and contributes greatly to the structural integrity of collagenous tissues. Conversely, defects in cross-link formation can significantly alter fibrillar organisation and lead to pathogenesis. Because collagen cross-links form on collagen-specific hydroxylated lysine residues, an understanding of the link between hydroxylysine and cross-link concentrations is needed to determine whether the level of hydroxylysine, the stereochemistry of these hydroxylysine residues, or other post-translational modifications such as glycosylation affect the level of cross-linking in tissue. While some research has been done to elucidate the connection between the two in different tissue types from the same animal, little has been undertaken to relate hydroxylation and glycosylation of lysine and hydroxylysine to the concentration and types of cross-links in different species. Furthermore, no research has been done to compare the relative distribution of diastereomers of hydroxylysine even within the same species. In order to make a valid comparison, collagen needs to be purified from skin to a high degree and separated into different collagen types and sub- structures as much as possible. To achieve this, the extraction and purification of collagen from the skins of four different mammalian species displaying different skin tensile strengths has been optimised. Different extraction methods were used to prevent the loss of specific features of the collagens that were characterised that may otherwise be lost. Amino acid analysis revealed that while the ratios of the two hydroxylysine diastereomers differed between different animals and extraction methods, the differences were not significant. Mass spectral analysis of cross-links showed that goat skin differed from the other three animals in its cross-link profile. Amino acid analysis combined with mass spectral analysis revealed that on average 70% of proline residues were hydroxylated, a figure much higher than previously thought. Mass spectral analysis also revealed that there are some differences between the glycosylation pattern of different animals, and the ratios of the different types of collagen which are extracted from each animal. While these findings need to be confirmed, they challenge some long held beliefs about the collagen molecule and provide a firm foundation for future work.
Use of small angle x-ray scattering in investigations of leather and the cornea : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Engineering at Massey University, Manawatū, New Zealand
(Massey University, 2018) Kelly, S. J. R.
Collagen is the most abundant protein in the body and the major structural component of skin and the cornea, where it provides strength and is an important physical and chemical barrier against the environment. The biological function of collagen lies predominantly in its mechanical properties where its structural arrangement greatly influences the tissue characteristics. Understanding collagen structure, its properties and how these are affected by processing, is essential for the manufacture of skin products with superior function and when considering collagen in abnormal corneal tissue. Leather is derived from skins of various animals, providing aesthetically pleasing products that are strong and hard wearing because of their collagen structure. Collagen is comprised of fibrils which have been studied here in leather produced from skins of ovine (sheep), bovine (cattle) and cervine (deer) origins. Small angle X-ray scattering (SAXS) was used to evaluate the collagen fibril structure and alignment in leather, processed normally and by stretch-tanning, along with tear and bend testing. The average collagen fibril direction at standard sampling points in all species was perpendicular to the backbone, with the average fibril orientation relative to the backbone being 44° in cervine, 66° in bovine and 79° in ovine. The orientation index (OI) suggests the relative alignment of the fibrils, where 1 is perfectly aligned and 0 is randomly aligned. The OI was lowest in cervine (0.24), suggesting a more mesh-like arrangement, increasing in bovine (0.38) and highest in ovine (0.44) where fibrils lay more parallel to one another. There was considerable and unpredictable variability in collagen arrangements in each species but a significant difference in tear strength with ovine leather (21 N/mm) being weakest, and cervine leather (53 N/mm) stronger than bovine leather (43 N/mm), making ovine leather not suitable for high value applications like footwear. Previous correlations between leather strength and fibril alignment suggest greater alignment led to greater strength. When fibrils were aligned artificially by stretch-tanning, the OI in ovine leather increased from 0.48 to 0.79 as did the strength from 27 to 43 N/mm, making it comparable to bovine leather strength. Measurements of the bend modulus of stretch-tanned ovine leather, which was stiffer than the non-stretch tanned leather (15 vs. 34 kPa), when conditioned under increasing relative humidity environments, during which water was incorporated into leather’s collagen structure, resulted in a 66% reduction in stiffness. Examination of clinically normal sheep corneas were used to determine effects of common preservatives on collagen structures using SAXS. Compared to the control, frozen cornea, there was a significant increase in the fibril diameter and D-spacing of collagen in corneas stored for 5 days in all the preservatives studied (5% glutaraldehyde, 10% formalin, Triton X and phosphate buffered saline). Corneas from cats with corneal opacities (Florida spots) that were studied using histology, transmission electron microscopy (TEM) and SAXS showed that there was less collagen in the stroma of the lesions. Here collagen fibrils had larger and more variable diameters (32 nm vs. the normal 27 nm), and a greater relative alignment (OI) compared to normal corneas (0.43 vs. 0.29, respectively). These changes explain the opacity of the lesions as corneal transparency depends on regular small fibril diameters which are aligned orthogonally. The above studies have demonstrated the usefulness of SAXS in characterizing collagen in natural, pathological, and mechanically and chemically altered collagen-based samples.
The characterisation of key processes in sous vide meat cooking : a thesis presented in partial fulfilment of the requirements for the degree of Masters in Engineering at Massey University, Manawatu, New Zealand
(Massey University, 2018) Fareh, Aden
Sous vide (French for “under vacuum”) is a method of cooking under precisely controlled conditions, which employs the principles of long-time-low temperature treatment. Better control over texture, flavour, and doneness are a few of the numerous advantages that sous vide enjoys over traditional methods of cooking. However, the requirement of a long time makes the sous vide process often uneconomical at industrial scale, particularly when applied to tougher cuts of meat, briskets for example. To improve the economics of the process, it is essential to better characterise the sous vide process, specifically understanding the cook-loss, how different conditions affect the extent of collagen dissolution and tenderisation will enable products with better sensory to be produced. The aim of the current work was, therefore, to characterise the key processes in order to facilitate the optimisation of sous vide cooking. Samples of beef semitendinosus (‘eye of round’) were cut into blocks of approximately 60x60x100 mm and were cooked at 50—60 °C (in increments of 2 °C), 70, 80, and 90 °C for five time-points: 1.5—73.5, 1.5—49.5, 1.5—25.5, and 1.5—9.5 hours, respectively. Cook loss (CL), Warner—Bratzler shear force (WBSF), total collagen in raw samples (TC), cook-loss-heat-soluble collagen (CLDC), and percent dissolved collagen within the cooked meat (%CMDC) were all measured (a new method was developed for determining %CMDC as no existing methods were found). Kinetic models were developed for the rate of CL and the CLDC as a function of temperature. A rapid cook-loss (which was attributed to the denaturation of myofibrillar proteins) followed by slow phase was observed for all temperatures. The higher temperatures (70—90 °C) showed a similar equilibrium cook-loss of approximately 42%. The cook-loss of the lower temperatures did not, however, equilibrate but showed an increasing trend with increasing temperature. The WBSF measurements showed a sharp increase (from the raw measurements) then sharp decline, followed by a slow decline phase. The TC was found to be 35 mg-collagen/g-meat. The CLDC increased with both time and temperature – the highest measured value was 3.15 mg-collagen/ml-cook-loss (80 °C, 25.5 hours). This value is very low compared to the TC and therefore CLDC is not an accurate measure of the dissolved collagen within the meat. The %CMDC increased with increasing temperature and to a lesser extent the time – the maximum %CMDC was 80% (90 °C, 9.5 hours). A two reaction, non-isothermal, first order (with fitted kinetic parameters) system was found to satisfactorily model both the CL and CLDC. Although the mechanism of meat tenderisation is complex, the dissolution of collagen, the denaturation of myofibrillar proteins, and the level of cook-loss appear to be the key factors influencing the tenderness of the resulting meat. The developed conceptual model integrates the key factors and shows how these undergo changes as the temperature is increased, but further research is required to elucidate these and to develop tools to rapidly identify processing conditions for different meat cuts and products.
Effect of slaughter age between 5 and 14 months on the quality of sheep meat with specific focus on collagen concentration and solubility : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Science in Animal Science at Massey University, Manawatu, New Zealand
(Massey University, 2017) Mashele, Grace Arbogast
In New Zealand, pasture-raised lamb is considered the highest quality sheep meat product while hogget is a downgraded product considered to be of poorer quality. The objectives of this study were to investigate the difference in meat quality between sheep slaughtered at 5, 8 and 14 months-of-age. This study also aimed to develop an assay to measure collagen concentration and solubility and to compare shear force to collagen concentration and solubility for meat from sheep slaughtered at 5, 8 and 14 months. Sixty Romney crossbreed rams born in the spring of 2015 were allocated to one of three slaughter age groups: 5-group (n=20), 8-months group (n=20) and 14-months group (n=20). The ram lambs were grazed together on perennial ryegrass-based pasture. At slaughter, the loin (Longissimus lumborum) from the left side of the carcass was excised, chilled for 24 hours and then frozen. Shear force, pH, colour, driploss, myofibrillar fragmentation index, sarcomere length, soluble collagen, insoluble collagen and total collagen were measured on the loin. Longissimus lumborum muscle from the 5-months group was darker (P=0.045) with higher pH (P<0.001) than 8 and 14-months groups. Longissimus lumborum muscle from the 14-months group was redder (P<0.001), yellower (P<0.001) with higher intramuscular fat (0.003), shorter sarcomere length (P<0.001), lower collagen concentration (P=0.020) and lower soluble collagen in percentage (P=0.007) and in g/100g fresh weight (P=0.008) than 5 and 8-months groups. The peak shear force was lower at 14 months, intermediate at 5 months and greater at 8 months (P<0.001). Longissimus lumborum muscle from the 8-months group had greater drip loss (P<0.01) than 5-months group and 14-months group. The results suggest that slaughtering sheep at 14 months could have benefits on eating quality due to an increase in intramuscular fat.
The structure and performance of collagen biomaterials : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Engineering, Massey University, Palmerston North, New Zealand
(Massey University, 2016) Wells, Hannah
Type I collagen materials are used in a wide range of industrial applications. Some examples include leather for shoes and upholstery, acellular dermal matrix (ADM) materials for surgical applications, and bovine pericardium for the fabrication of heart valve replacements. The structure of these materials is based on a matrix of collagen fibrils, largely responsible for the physical properties and strength of the materials. How the collagen fibrils themselves contribute to the overall bulk properties of these materials is not fully understood. The first part of this work investigates a collagen structure defect in leather, known as looseness. Looseness occurs in around 5-10% of bovine leather, and is a result of the collagen fibril layers separating during processing from raw kkin to leather. A greater understanding of why looseness develops in leather and a method of detecting looseness early in processing is needed to save tanners a significant amount on wasted processing time and costs. In addition, an environmentally safe method of disposing of defect and waste leather is sort after since the current method of disposing to landfill is causing environmental concern due to the possibility of chromium leaching from leather into the soil as it biodegrades. Synchrotron based small angle X-ray scattering (SAXS) revealed that loose leather has a more aligned and layered collagen fibril arrangement, meaning there is less fibril overlap, particularly in the grain-corium boundary region. This results in larger gaps in the internal structure of loose leather compared with tight. These gaps could be detected using ultrasonic imaging in partially processed pickle and wet-blue hides as well as leather. Incorporating an ultrasound system into the leather processing line could be a viable method for identifying hides deemed to develop looseness earlier in processing, and these could be diverted down a separate processing line or removed. Disposing of waste leather by first forming biochar prior to land fill proved to be an effective way of reducing chromium from leaching into the environment. XAS revealed that heating leather to temperatures above 600°C in the absence of oxygen formed a char where chromium was bound in the stable form of chromium carbide. The stability of this structure makes chromium less available to form the toxic hexavalent form in the environment and presents a possible alternative option for environmentally safe disposal of leather. The second part to this work looks at the correlation between collagen fibril structure in a range of biomaterials in relation to material strength. Leather, ADM and pericardium are three type I collagen based materials which rely on sufficient strength to carry out their industrial and medical applications. These three materials were studied to try and identify collagen fibril characteristics that relate to high material strength. SAXS on a range of leather samples from various species revealed that collagen fibril diameter had only a small influence over material strength in bovine leather, and no correlation to strength in leather from other species. Therefore it can be said that the influence of fibril orientation on leather strength takes precedence over that of fibril diameter. Fibril diameter, d-spacing and orientation were studied in pericardium using SAXS while simultaneously applying strain. It was revealed collagen materials undergo two distinct stages of deformation when strain is applied and incrementally increased. The first stage, at low strain, involves a re-orientation of fibrils to become more aligned. When strain is increased further, the fibrils themselves take up the strain, causing fibrils to stretch and decrease in diameter. The Poisson ratio of the collagen fibrils was calculated to be 2.1 ± 0.7. This high Poisson's ratio indicates the fibrils decrease in diameter at a faster rate than they elongate with strain, and as a result the volume of the fibrils decreases. This feature of collagen could help explain some of the unique behaviours and strength of collagen based materials and could be useful for optimizing industrial applications of collagen materials. ADM materials, derived from human, porcine and bovine skin was the third collagen material studied. SAXS revealed that each species of ADM material had a slightly different collagen fibril arrangement when viewing the samples perpendicular to the surface. Human ADM was highly isotropic in arrangement, porcine was largely anisotropic, and bovine was somewhere in between the two. Bovine has a more layered fibril arrangement edge on and was the strongest material, followed by human ADM, and porcine was significantly weaker. Bovine was also the most porous material of the three. The discovery of the variations in strength, porosity and fibril arrangement between the three types of ADM materials may help medical professionals select the most suitable material for specific surgical procedures and could lead to a greater number of successful surgeries taking place.

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