Hydrolyzed Form Research Articles

Attractiveness, longevity, and release rates of multilure wafers for trapping males of the oriental fruit fly and melon fly (Diptera: Tephritidae).

Invasive fruit flies (Diptera: Tephritidae) pose a serious threat to the production and export of many commercially important fruits and vegetables. Detection of the agricultural pests Bactrocera dorsalis (Hendel) and Zeugodacus cucurbitae (Coquillett) relies heavily on traps baited with male-specific attractants. For B. dorsalis, traps are typically baited with liquid methyl eugenol (ME), and for Z. cucurbitae, traps are baited with liquid cue-lure (CL). Operating large-scale trapping networks is costly, consequently, there is much interest in identifying ways to maintain network sensitivity while reducing costs. One cost-cutting approach is the possibility of combining different male lures in the same dispenser, thus reducing the number of traps requiring servicing. The chief objective of this study was to compare captures of B. dorsalis and Z. cucurbitae males in Jackson traps baited with polymeric wafers impregnated with both ME and raspberry ketone (RK, a hydrolyzed form of CL) versus traps baited with liquid ME or CL freshly applied to cotton wicks. Captures were measured when the ME/RK wafers had been weathered for 12, 18, or 24wk. Captures of B. dorsalis and Z. cucurbitae males were similar between fresh lure and weathered wafers over all trapping periods, with a single exception apparently due to the lessened potency of the associated killing agent. The residual amount and release rate of ME and RK from the wafers were also measured to examine possible relationships between wafer chemistry and trap catch. The possible implications of the present results to area-wide trapping programs are discussed.

Study of reactive dyes and their hydrolyzed forms in a real trichromatic dyeing process by capillary electrophoresis with UV detection.

Detecting the concentration of reactive dyes and their hydrolyzed products is essential for controlling the dyeing process and is an important guide for upgrading and improving textile dyeing technology. In this study, capillary electrophoresis (CE) with UV detection was for the first time applied in a real trichromatic dyeing process to provide qualitative and quantitative determination of reactive dyes and their hydrolyzed forms. Here, three original reactive dyes (SES-Cl-red-195, SES-Cl-yellow-145, and SES-Cl-blue-194), their vinyl sulfone forms (VS-Cl-red-195, VS-Cl-yellow-145, and VS-Cl-blue-194), and complete hydrolyzed forms (HES-OH-red-195, HES-OH-yellow-145, and HES-OH-blue-194) could be baseline separated in our developed BGE comprised of 10.0 mol/L Na2B4O7, 15% (V/V) ACN at pH 8.50 that adjusted by 0.50 mol/L H3BO3. The LODs (S/N = 3) of nine analytes ranged from 0.3 to 1.3 mg/L, and high sensitivities were achieved with UV detection. The RSDs of peak area and migration time were in the ranges of 1.4-3.8% and 0.39-1.29%, which indicated the CE methods were reliable for studying different dye forms in complex dye baths, and for evaluating dyeing process quality. Thus, the percentage of dye-uptake in single and trichromatic combination dyes was calculated based on the concentration of the original and their vinyl sulfone and hydrolyzed forms, and the result was consistent with the traditional UV-Vis method.

Natural and synthetic plagioclases: Surface charge characterization and sorption of trivalent lanthanides (Eu) and actinides (Am, Cm)

The environmental fate of radiotoxic actinides may be controlled by their interactions with feldspars. Here, the sorption of trivalent minor actinides (Am, Cm) and their rare earth analog Eu onto synthetic pure Ca-feldspar (anorthite) and natural plagioclases of different Ca contents is investigated, covering ranges of [M3+] (52 nM–10 μM), solid-liquid ratios (1–3 g/L), pH (3–9), and ionic strengths (0.01–0.1 M NaCl) under both ambient and CO2-free conditions. As a first step to understand the uptake behavior of the heavy metals, the hitherto unknown surface charge and (de-)protonation reaction of Ca-feldspars is characterized. The zeta potential shows an unusual increase and charge reversal between pH 4 and 7 , which becomes more pronounced with increasing amounts of Ca in the crystal lattice and is likely connected to adsorption and/or surface precipitation of dissolved Al3+. Streaming potential measurements yield (de)protonation constants for anorthite surface sites of log K- = −6.94 ± 0.38 and log K+ = +6.84 ± 0.38. Batch sorption data shows strong immobilization of M3+ by plagioclases at mildly acidic and basic pH. Time-resolved laser fluorescence spectroscopy using Cm indicates the formation of an inner-sphere complex and its two hydrolyzed forms. The complex reactivity of dissolved Al3+ at the plagioclase-water interface severely complicated the development of a surface complexation model, emphasizing the need for additional research in this area. Our study highlights the importance of molecular-level studies to understand surface reactions and uncover unknown processes, which may have significant impact on the transport of (radiotoxic) contaminants in the geosphere.

Improved Generation, Physicochemical Characteristics, and Food Application Studies of a Red Colorant Obtained from Oxidative Coupling of Chlorogenic Acid and Tryptophan.

Due to a widespread consumer reluctance toward synthetic food dyes, the interest in natural compounds from plants has increased. This study aimed to optimize the oxidation process between chlorogenic acid (CQA) and tryptophan (Trp) using sodium periodate (NaIO4) to obtain a red-colored pigment. The impact of temperature and different ratios of Trp to NaIO4 on the reaction progress was investigated. After the best conditions for the reaction were established, three pH values were tested. The reaction time could be reduced from 72 to 24 h with a yield of 46 ± 2% w/w based on the quantity of CQA. After the first purification step of the product by size exclusion chromatography, the pigment obtained was characterized for its solubility, and its hydrolyzed form was used for investigations into the stability at different pH values, storage under light and in the dark (period of 28 days), in the presence of reducing agents, and for heat resistance. Finally, several food matrices were successfully colored with the natural pigment in amounts from 0.005 to 0.01% (w/w). In conclusion, the present study provides new insights into the feasible production and comprehensive characterization of a red pigment derived from oxidative coupling of CQA and Trp, as well as its application in food systems.

Electromediated Oxidation of Hydrolysed Bacterial Cellulose

The state-of-the-art method to isolate cellulose nanofibres employs a 2,2,6,6-Tetramethylpiperidinyloxyl (TEMPO)/NaBr/NaClO system, where the primary alcohols on the surface of cellulose microfibrils are oxidised. However, the large consumption of hypochlorite in this system makes it problematic for industrial implementation. Previously, electrochemical oxidation with a TEMPO catalyst has been reported for the preparation of cellulose nanofibres. Here, we present a study on the electromediated oxidation of bacterial cellulose (BC), the purest form of cellulose. BC has been used in a hydrolysed form, enabling the electromediated preparation of cellulose nanocrystals (CNCs), which is generally deemed even more costly than the preparation of cellulose nanofibres.In this work, the electromediated oxidation and cyclic voltammetry were performed in an electrochemical cell, which featured three electrodes: A Hg|Hg2SO4|K2SO4 reference electrode, a titanium net counter electrode, and a carbon foam working electrode, offering a high surface area. A static potential of 0.5 V was applied during the chronoamperometry and explored oxidation times were 3, 5, 9, 12 and 24 h.Using a TEMPO catalyst, the electromediated oxidation was applied to hydrolysed and non-hydrolysed BC fibres in a pH 10 buffer. The C6 primary hydroxyls of BC were successfully converted to sodium carboxylate groups. By the application of the TEMPO electro-mediated oxidation to hydrolysed BC for 9 h, high carboxylate and aldehyde concentrations of 1.4 and 0.3 mmol/g, respectively, were formed in the oxidized fibre. The carboxylate and aldehyde content was determined by a conductometric titration method. Surface morphologies after oxidation were investigated, showing alteration of the microfibril morphology for BC and the production of cellulose nanocrystals for hydrolysed BC. Hence, we present an effective and environmentally friendly route, which is particularly suitable for the preparation of cellulose nanocrystals.

Standardization of food allergen ladders for optimal effectiveness and patient safety.

The use of extensively heated (EH) milk and egg products, and dietary advancement therapies such as milk and egg ladders is increasingly common for the management of milk and egg allergies. Although the majority of patients with milk and egg allergies will outgrow their allergies, the ability to tolerate extensively hydrolyzed forms of these allergens is an early indicator of developing long-term tolerance. The denaturation of conformational epitopes during the heating process reduces the allergenicity of these proteins, which makes patients who are EH tolerant more likely to tolerate progressively more of these proteins.

Neodymium sorption on the Na-form of Transcarpathian clinoptilolite

The sorption properties of Na-modified Ukrainian Transcarpathian clinoptilolite towards neodymium aqueous solutions under dynamic conditions have been investigated. The sorption capacity of the Na-from of Transcarpathian clinoptilolite towards Nd(III) significantly depends on the concentration of neodymium salt, the pH of the solution, and the heat treatment temperature of the sorbent. Nd(III) is most efficiently sorbed from slightly alkaline solutions (pH 8.5), mainly by adsorption of neutral hydrolyzed forms of Nd(OH)3 on the surface of Na-clinoptilolite samples preheated at 75 °C. During the passage of an Nd(III) solution with a concentration of 1 μg mL−1 through the sorbent at a rate of 3 mL min−1 under optimal conditions, the sorption capacity of Na-clinoptilolite is 7.2 mg g−1, which is in 4 and 2.3 times higher than that of natural and acid-modified forms of this zeolite. It is shown that under the experimental conditions with an increase in the flow rate, the thickness of the stationary surface layer decreases, which leads to a decrease in the sorption capacity of Na-clinoptilolite. The best Nd(III) desorbents are solutions of mineral acids and acidified solutions of alkali metal salts (except NaCl), which provide 93–98 % extraction of lanthanide from the zeolite matrix. The method for neodymium trace amounts preconcentration from aqueous solutions in a solid-phase extraction mode with a further determination of this rare earth element by a spectrophotometric method was developed. The detection limit of this method is 0.75 ng mL−1 and the linearity was evaluated in the range of 2.5–500 ng mL−1.

Potato Peel Waste as an Economic Feedstock for PHA Production by Bacillus circulans.

Polymers of hydroxy alkanoates (PHA), also known as biodegradable, biocompatible plastic, are potential alternatives to petrochemical-based plastics. PHA is synthesized by microbes in their cytoplasm in the form of inclusion bodies in stress conditions such as nitrogen, oxygen, and phosphorus with excessive amounts of carbon. Sugar extracted from potato peel in the form of hydrolysate was employed as a carbon source for PHA production after acidic hydrolysis. The acid hydrolysis conditions are optimized for dilute acid concentrations and temperatures. The highest sugar-yielding condition (2% 15min at 121 ℃) was used for submerged fermentation for PHA production by Bacillus circulans MTCC 8167. Fourier transform infrared spectroscopy, nuclear magnetic resonance, and differential scanning calorimetry were used for polymer characterization. Gas chromatography coupled with mass spectrometry confirmed the monomers such as hexadecenoic acid 3-hydroxy, methyl esters, pentadecanoic acid 14 methyl esters, and tetradecanoic acid 12- methyl esters. Crotonic acid assay was used for quantification of PHA and it was found highest (0.232 ± 0.04g/L) at 37°C and 36h of incubation. Hence, potato peel waste could be a potential feedstock for waste to valuable production.

Investigation of changes in the viscosity properties of acrylamide (co)polymer and their hydrolyzed forms depending on the conditions of their preparation

Investigation of changes in the viscosity properties of acrylamide (co)polymer and their hydrolyzed forms depending on the conditions of their preparation

Strategy of In Situ Electrochemical Regulation for Highly Enhanced Nonenzymatic Sensing of Carbaryl.

Specific and sensitive sensing of most pesticide residues relies on enzymes such as acetylcholinesterase and advanced materials, which need to be loaded on the surface of working electrodes, leading to instability, uneven surface, tedious process, and high cost. Meanwhile, employing certain potential or current in electrolyte solution could also modify the surface in situ and overcome these drawbacks. However, this method is only regarded as electrochemical activation widely applied in the pretreatment of electrodes. In this paper, by means of regulating the electrochemical technique and its parameters, we prepared a proper sensing interface and derivatized the carbaryl (a carbamate pesticide) hydrolyzed form (1-naphthol) to enhance sensing by 100 times within several minutes. After regulation I by chronopotentiometry with 0.2 mA for 20 s or chronoamperometry with 2 V for 10 s, abundant oxygen-containing groups form and the ordered carbon structure is destroyed. Sweeping from -0.5 to 0.9 V through cyclic voltammetry for only one segment, following regulation II, the composition of oxygen-containing groups changes and the disordered structure is alleviated. Finally, on the constructed sensing interface, test by regulation III through differential pulse voltammetry from 0.8 to -0.4 V, resulting in derivatization of 1-naphthol during 0.8-0 V, followed by electroreduction of the derivative at around -0.17 V. Compared with the electro-oxidation peak at 0.5 V in previous reports, it is essential to improve specificity, even toward several other carbamate pesticides with similar structures. Hence, the in situ electrochemical regulation strategy has demonstrated great potential for effective sensing of electroactive molecules.

Evaluation of In Vitro Distribution and Plasma Protein Binding of Selected Antiviral Drugs (Favipiravir, Molnupiravir and Imatinib) against SARS-CoV-2.

There are a number of uncertainties regarding plasma protein binding and blood distribution of the active drugs favipiravir (FAVI), molnupiravir (MOLNU) and imatinib (IMA), which were recently proposed as therapeutics for the treatment of COVID-19 disease. Therefore, proton dissociation processes, solubility, lipophilicity, and serum protein binding of these three substances were investigated in detail. The drugs display various degrees of lipophilicity at gastric (pH 2.0) and blood pH (pH 7.4). The determined pKa values explain well the changes in lipophilic character of the respective compounds. The serum protein binding was studied by membrane ultrafiltration, frontal analysis capillary electrophoresis, steady-state fluorometry, and fluorescence anisotropy techniques. The studies revealed that the ester bond in MOLNU is hydrolyzed by protein constituents of blood serum. Molnupiravir and its hydrolyzed form do not bind considerably to blood proteins. Likewise, FAVI does not bind to human serum albumin (HSA) and α1-acid glycoprotein (AGP) and shows relatively weak binding to the protein fraction of whole blood serum. Imatinib binds to AGP with high affinity (logK' = 5.8-6.0), while its binding to HSA is much weaker (logK' ≤ 4.0). The computed constants were used to model the distribution of IMA in blood plasma under physiological and 'acute-phase' conditions as well.

Effect of Storage Time and Bacterial Strain on the Quality of Probiotic Goat's Milk Using Different Types and Doses of Collagens.

Recently, increasing attention has been focused on developing new products based on goat’s milk. Consumers positively perceive fermented goat’s milk products as health-promoting due to their nutritional value, digestibility, and potential source of probiotics. This study aimed to evaluate the possibility of using different doses of collagen and collagen hydrolysate in the production of probiotic goat’s milk fermented by four monocultures: Lacticaseibacillus casei 431® Lactobacillus acidophilus LA- 5®, Lacticaseibacillus paracasei LP26, and Lacticaseibicillus rhamnosus Lr- 32®. A total of 20 experimental groups were prepared, including control groups (without additives), and due to the added probiotic (Lacticaseibacillus casei, Lactobacillus acidophilus, Lacticaseibacillus paracasei, and Lacticaseibacillus rhamnosus), various collagen doses (1.5% and 3.0%) and collagen types (hydrolysate and bovine collagen). Physicochemical, organoleptic, and microbiological characteristics were evaluated after 1 and 21 days of cold storage. The applied additives increased the acidity of the milk even before fermentation. However, milk with bovine collagen and hydrolysate had a higher pH value after fermentation than control milk. The study showed higher than 8 log cfu g−1 viability of probiotic bacteria in goat’s milk products during storage due to the proper pH, high buffering capacity, and rich nutrient content of goat’s milk. The best survival rate was shown for the L. casei strain after 21 days in milk with collagen protein hydrolysate. Moreover, collagen in milk fermented by L. rhamnosus decreased syneresis compared to its control counterpart. The addition of collagen, especially the hydrolysate, increased the gel hardness of the fermented milk. The collagen additives used in the milk, both in the form of hydrolysate and bovine collagen, caused a darkening of the color of the milk and increased the intensity of the milky-creamy and sweet taste.

Hydrolysis, Microstructural Profiling and Utilization of Cyamopsis tetragonoloba in Yoghurt

The present study investigates the hydrolysis, microstructural profiling and utilization of guar gum (Cyamopsis tetragonoloba) as a prebiotic in a yoghurt. Guar galactomannans (GG) was purified and partially depolymerized using an acid, alkali and enzyme to improve its characteristics and increase its utilization. The prebiotic potential of hydrolyzed guar gum was determined using Basel and supplemented media. Crude guar galactomannans (CGG), purified guar galactomannans (PGG), base hydrolyzed guar galactomannans (BHGG), acid hydrolyzed guar galactomannans (AHGG) and enzymatic hydrolyzed guar galactomannans (EHGG) were analyzed using scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Yoghurt was prepared with a starter culture and incorporating guar gum, its hydrolyzed forms (0.1, 0.5 and 1%) and Bifidobacterium bifidum. The results showed that PHGG significantly improved the viability of B. bifidum. SEM revealed a significant change in the surface morphology of guar gum after acidic and enzymatic hydrolysis. Enzymatic hydrolysis developed a well-defined framework within guar gum molecules. The XRD pattern of CGG, PGG and AHGG presented an amorphous structure and showed low overall crystallinity while EHGG and BHGG resulted in slightly increased crystallinity regions. FTIR spectral analysis suggested that, after hydrolysis, there was no major transformation of functional groups. The addition of the probiotic and prebiotic significantly improved the physiochemical properties of the developed yoghurt. The firmness, cohesiveness, adhesiveness and syneresis were increased while consistency and viscosity were decreased during storage. In sum, a partial hydrolysis of guar gum could be achieved using inexpensive methods with commercial significance.

Perirenal adipose tissues as a human elastin source, and optimize the extraction process.

Elastin is very rarely repaired extracellular matrix (ECM) in physiological condition. The commercial human elastin for exogenous medical treatment is very expensive, and has a potential for disease transmission. Animal-origin elastin is relatively low price, but has concerns for xenogeneic immune responses. Considering cost and safety, we focused on the perirenal adipose tissue, donated from healthy young people via donor nephrectomy. Until now, all of the perirenal adipose tissues are discarded as a medical waste after kidney transplantation. In the present study, we applied perirenal adipose tissues as the source of human elastin, and optimized the extraction process to get high purified and quantified elastin. Through pre-processing step, the delipidated and decellularized ECM was prepared. Next, with four different elastin extraction process (acidic solvents, neutral salt, organic solvents or hot alkali method), elastin was extracted, and the concentration of amino acid between each product was compared, and bright-field/electron microscopy, Fourier transform infrared (FT-IR) spectroscopy and cytotoxicity analysis were also performed. As controls, bovine neck ligament-derived and human skin-derived elastin were used. Among the elastin extraction methods, the hot alkali insoluble product showed (1) relatively high positive area of Verhoeff's and low Masson's trichrome stain, (2) 64.24% purity, 159.29mg/g quantity, and ∼6.37% yield in amino acid analysis, (3) β-sheet second structure, and (4) thin fiber composed mesh-like sheet structure in SEM image. These values were higher than those of the commercial human skin elastin. When comparing hydrolyzed forms, α-elastin from hot alkali insoluble product showed enhanced cell proliferation and maintained cell properties compared to the κ-elastin. Therefore, we confirmed that the perirenal adipose tissue is an ideal source of human elastin with safety assurance, and the hot alkali process combined with pre-process seems to be the optimal method for elastin extraction with high purity and quantity.

Reduced Dehydroepiandrosterone-Sulfate Levels in the Mid-Luteal Subphase of the Menstrual Cycle: Implications to Women's Health Research.

The regulation of DHEA-sulfate by steroid sulfotransferase (SULT) and steryl-sulfatase (STS) enzymes is a vital process for the downstream formation of many steroid hormones. DHEA-sulfate is the most abundant steroid hormone in the human body; thus, DHEA-sulfate and its hydrolyzed form, DHEA, continue to be evaluated in numerous studies, given their importance to human health. Yet, a basic question of relevance to the reproductive-age female population—whether the two steroid hormones vary across the menstrual cycle—has not been addressed. We applied a validated, multi-step protocol, involving realignment and imputation of study data to early follicular, mid-late follicular, periovulatory, and early, mid-, and late luteal subphases of the menstrual cycle, and analyzed DHEA-sulfate and DHEA serum concentrations using ultraperformance liquid chromatography tandem mass spectrometry. DHEA-sulfate levels started to decrease in the early luteal, significantly dropped in the mid-luteal, and returned to basal levels by the late luteal subphase. DHEA, however, did not vary across the menstrual cycle. The present study deep-mapped trajectories of DHEA and DHEA-sulfate across the entire menstrual cycle, demonstrating a significant decrease in DHEA-sulfate in the mid-luteal subphase. These findings are relevant to the active area of research examining associations between DHEA-sulfate levels and various disease states.

Fish processing waste: a novel source of non‐conventional functional proteins

SummaryFish waste has now become one of the serious problems worldwide, and its disposal without proper management could result in serious environmental pollution and nutrient loss. These wastes contain several biological and nutritional compounds, if recovered has a lot of promise. With the recent technological developments, many bioactive and functional compounds can be recovered from these wastes. The vast quantity of bioactive chemicals found in seafood processing by‐products has prompted the development of valorisation strategies for their extraction. The future of fish processing waste for reuse and bioconversion is bright with the right mindset and achieve progress in the future. Proteins have advanced significantly in recent years, piquing the interest of many academics around the world. Therefore, fish proteins can be extracted from the fish waste and can be further utilised for human and animal purposes in form of protein isolate, hydrolysate, gelatin, collagen, silage and fish meal.

Synthesis and biological evaluation of coumarin-thiazole hybrids as selective carbonic anhydrase IX and XII inhibitors.

A series of coumarin-linked thiazoles (6a-p) was synthesized and the synthesized compounds were evaluated against human carbonic anhydrases (hCAs) IX and XII, which have been implicated in cancer. All the compounds exhibited selective inhibition of both isoforms. The designed compounds inhibited hCA IX in a moderate nanomolar to submicromolar range. The hCA XII was inhibited in a low to moderate nanomolar range. Compound 6o exhibited the best inhibition of hCA XII with a Ki value of 91.1 nM. The hydrolyzed form of compound 6o also exhibited favorable interactions as well as good docking scores with both the isoforms. Hence, this compound can be taken as a template for the design of selective and potent hCA XII inhibitors.

Exploring the prebiotic potential of xanthan gum and its modified forms for the production of synbiotic yogurt

Crude xanthan gum was hydrolyzed using acid (HCl), base (NaOH), and enzyme (cellulase). Synbiotic yogurt was developed with the addition of xanthan gum and its hydrolyzed forms (0.1, 0.5, and 1% [w/v]) as prebiotic along with probiotics (Bifidobacterium longum BB536). Fat, protein, lactose, total solid contents, pH, and viscosity decreased, whereas syneresis and acidity were increased during the storage period of 28 days. The addition of hydrolyzed xanthan gum as prebiotic proved to be the best for enhancing the viability of yogurt culture and probiotics maintaining the viable count of the B. longum BB536 above 6 Log CFU/g during storage with maximum count of 7.898 Log CFU/g in yogurt containing 1% of enzyme hydrolyzed xanthan gum (EHXG). The addition of EHXG beyond this limit disturbed the final texture of yogurt due to phase separation. Hence, hydrolyzed xanthan gum can be the best candidates as prebiotics to be added in yogurt. Practical applications The finding of the present study is beneficiary from the industrial point of view in order to develop the versatile dairy products having valuable influence on human health that provide healthy gut functions with a balance between good and bad bacteria. The use of prebiotics from microbial sources (xanthan gum) will serve as a sustainable, fast, and cheaper source and can be obtained even from waste. The study will have a good economic impact when executed in the form of commercial synbiotic food products.

Effect of Collagen Types, Bacterial Strains and Storage Duration on the Quality of Probiotic Fermented Sheep's Milk.

Collagen has become popular in dietary supplements, beverages and sports nutrition products. Therefore, the aim of this study was to evaluate the possibility of using various doses of collagen and collagen hydrolysate to produce probiotic sheep’s milk fermented with Lactobacillus acidophilus, Lacticaseibacillus casei, Lacticaseibacillus paracasei and Lacticaseibacillus rhamnosus. The effects of storage time, type and dose of collagen, and different probiotic bacteria on the physicochemical, organoleptic and microbiological properties of fermented sheep’s milk at 1 and 21 days of refrigerated storage were investigated. The addition of collagen to sheep’s milk increased the pH value after fermentation and reduced the lactic acid contents of fermented milk compared to control samples. After fermentation, the number of probiotic bacteria cells was higher than 8 log cfu g−1. In sheep’s milk fermented by L. acidophilus and L. casei, good survival of bacteria during storage was observed, and there was no effect of collagen dose on the growth and survival of both strains. The addition of collagen, both in the form of hydrolysate and bovine collagen, resulted in darkening of the color of the milk and increased the sweet taste intensity of the fermented sheep’s milk. However, the addition of hydrolysate was effective in reducing syneresis in each milk sample compared to its control counterpart.

Evaluation of methane production from liquid hot water pretreated Paspalum atratum and Brachiaria ruziziensis as alternative energy substrates

Atratum and ruzi grasses have illustrated high potential for methane production through anaerobic digestion. To enhance the utilization of these grasses for the production of renewable biogas, liquid hot water pretreatment was applied to break down various lignocellulose matter, in particular, hemicellulose. After pretreatment under optimal conditions (200 °C for 15 min), more than 90% of hemicellulose was removed and solubilized in the form of a clear hydrolysate. Xylose was the primary sugar in the hydrolysate, appearing in several forms, and acting as the major substrate for methane production. Total xylose yields for the atratum and ruzi grasses were 58 and 74 mg/g TS respectively. The pretreated atratum and ruzi substrates were evaluated for methane production resulting in an increased methane yield of at least 14%, and more than 70% biodegradability. This work demonstrates the potential for atratum and ruzi grasses to be used as a viable alternative to other energy crops such as Napier grass.