Role of Synbiotics (Prebiotics and Probiotics) as Dietary Supplements in Type 2 Diabetes Mellitus Induced Health Complications.

Diabetes is a metabolic disorder whose prevalence has become a worrying condition in recent decades. Chronic diabetes can result in serious health conditions such as impaired kidney function, stroke, blindness, and myocardial infarction. Despite a variety of currently available treatments, cases of diabetes and its complications are on the rise. This review article provides a comprehensive account of the ameliorative effect of prebiotics and probiotics individually or in combination i.e. synbiotics on health complications induced by Type 2 Diabetes Mellitus (T2DM). Recent advances in the field underscore encouraging outcomes suggesting the consumption of synbiotics leads to favorable changes in the gut microbiota. These changes result in the production of bioactive metabolites such as short-chain fatty acids (crucial for lowering blood sugar levels), reducing inflammation, preventing insulin resistance, and encouraging the release of glucagon-like peptide-1 in the host. Notably, novel strategies supplementing synbiotics to support gut microbiota are gaining attraction as pivotal interventions in mitigating T2DM-induced health complications. Thus, by nurturing a symbiotic relationship between prebiotics and probiotics i.e. synbiotics, these interventions hold promise in reshaping the microbial landscape of the gut thereby offering a multifaceted approach to managing T2DM and its associated morbidities. Supporting the potential of synbiotics underscores a paradigm shift toward holistic and targeted interventions in diabetes management, offering prospects for improved outcomes and enhanced quality of life for affected individuals. Nevertheless, more research needs to be done to better understand the single and multispecies pre/pro and synbiotics in the prevention and management of T2DM-induced health complications.

Impact of Dietary Probiotics on the Immune and Reproductive Physiology of Pubertal Male Japanese Quail (Coturnix coturnix japonica) Administered at the Onset of Pre-Puberty.

Fertility in males is dependent on the proper production of sperms involving the synchronization of numerous factors like oxidative stress, inflammatory processes, and hormonal regulation. Inflammation associated with oxidative stress is also known to impair sperm function. Nutritional factors like probiotics and prebiotics have the potential benefits to modulate these factors which may enhance male fertility. In the present study, immature male Japanese quail at the beginning of 3rd week were administered with Lactobacillus rhamnosus (L), Bifidobacterium longum (B), and mannan-oligosaccharides (M) through dietary supplementation in individual groups as well as in combinations like LB and MLB. Markers of oxidative stress including SOD and catalase were examined by native PAGE; inflammatory biomarkers (IL-1ß, IL-10, and NFκB), apoptotic markers (caspase 3 and caspase 7), steroidal hormones, and their receptors estrogen receptor alpha (ERα) and beta (ERß) were assessed in testis. The study reveals that dietary supplementation of 1% L, B, and M in combination significantly and positively increases the overall growth of immature male quail specifically testicular weight and gonadosomatic index (GSI). Furthermore, significant improvement in testicular cell size; increased steroidal hormones like testosterone, FSH, and LH levels; increase in SOD, catalase enzymes; decrease in apoptotic factors Caspase 3, Caspase 7 and immune system strength observed indicated by a decrease in expression of IL-1ß, NFκB; and increase of IL-10 in testis when LBM was used in combination. These variations are attributed to the increase in testicular estrogen receptors alpha and beta, facilitated by the neuroendocrine gonadal axis, ultimately leading to improved male fertility. It can be concluded that the dietary supplementation in combination with L, B, and M enhances male fertility in immature quail by increased expression of estrogen receptors via gut microbiota modulation. It also sheds light on the potential use of these nutritional factors in avian species as therapeutic interventions to overcome low fertility problems in quail thereby benefitting the poultry industry.

Withaferin-A attenuates diabetes mellitus induced male reproductive dysfunction mediated by ERα in brain and testes of Swiss albino mice.

Diabetes mellitus (DM) is a chronic metabolic disease, characterized by persistent hyperglycemia resulting from diminished insulin secretion or insulin resistance. The present study evaluated the ameliorative effects of Withaferin-A (WA) on DM-induced reproductive dysfunction in mice. For the same, mice were intraperitoneally injected with Streptozotocin (STZ), (40 mg/kg/day) for 5 consecutive days to induce DM. Mice were then treated with WA (8 mg/kg/day) in normal and diabetic conditions (STZ + WA). Next, blood glucose levels, oral glucose tolerance, intraperitoneal insulin tolerance, oxidative stress and reproductive parameters were estimated. For reproductive performance, immunofluorescent localization of gonadotropin-releasing hormone (GnRH-I) and estrogen receptor alpha (ERα) in the preoptic area and paraventricular nucleus region of hypothalamus and ERα in testes was performed. STZ-induced diabetes triggered reproductive dysfunctions as mediated by low GnRH-I and ERα in the brain and ERα in the testes along with declined testosterone and estradiol levels. Treatment with WA significantly reduced the blood glucose levels and enhanced glucose clearance accompanied by reduced oxidative stress in the brain, pancreas and testes as indicated by the low levels of H2O2 and MDA in diabetic mice treated with WA (STZ + WA). This study reports, for the first time, that WA can efficiently ameliorate DM-induced reproductive dysfunctions by enhancing endogenous testosterone, estrogen and increased GnRH-I and ERα in the brain and ERα in the testes of DM-induced male mice.

Synthesis and characterization of keratinase laden green synthesized silver nanoparticles for valorization of feather keratin.

This study focuses on the efficient and cost-effective synthesis of silver nanoparticles (AgNPs) using plant extracts, which have versatile and non-toxic applications. The research objectives include synthesizing AgNPs from readily available plant extracts, optimizing their production and multi scale characterization, along with exploring their use for enzyme immobilization and mitigation of poultry feather waste. Among the plant extracts tested, the flower extract of Hibiscus rosa-sinensis (HF) showed the most potential for AgNP synthesis. The synthesis of HF-mediated AgNPs was optimized using response surface methodology (RSM) for efficient and environment friendly production. Additionally, the keratinase enzyme obtained from Bacillus sp. NCIM 5802 was covalently linked to AgNPs, forming a keratinase nanocomplex (KNC) whose biochemical properties were evaluated. The KNC demonstrated optimal activity at pH 10.0 and 60 °C and it displayed remarkable stability in the presence of various inhibitors, metal ions, surfactants, and detergents. Spectroscopic techniques such as FTIR, UV-visible, and X-ray diffraction (XRD) analysis were employed to investigate the formation of biogenic HF-AgNPs and KNC, confirming the presence of capping and stabilizing agents. The morphological characteristics of the synthesized AgNPs and KNC were determined using transmission electron microscopy (TEM) and particle size analysis. The study highlighted the antimicrobial, dye scavenging, and antioxidant properties of biogenic AgNPs and KNC, demonstrating their potential for various applications. Overall, this research showcases the effectiveness of plant extract-driven green synthesis of AgNPs and the successful development of keratinase-laden nanocomplexes, opening possibilities for their use in immobilizing industrial and commercial enzymes.

Parametrically optimized feather degradation by Bacillus velezensis NCIM 5802 and delineation of keratin hydrolysis by multi-scale analysis for poultry waste management.

Enormous amounts of keratinaceous waste make a significant and unexploited protein reserve that can be utilized through bioconversion into high-value products using microbial keratinases. This study was intended to assess the keratinase production from a newly isolated B. velezensis NCIM 5802 that can proficiently hydrolyze chicken feathers. Incubation parameters used to produce keratinase enzyme were optimized through the Response Surface Methodology (RSM) with chicken feathers as substrate. Optimization elevated the keratinase production and feather degradation by 4.92-folds (109.7 U/mL) and 2.5 folds (95.8%), respectively. Time-course profile revealed a direct correlation among bacterial growth, feather degradation, keratinase production and amino acid generation. Biochemical properties of the keratinase were evaluated, where it showed optimal activity at 60 °C and pH 10.0. The keratinase was inhibited by EDTA and PMSF, indicating it to be a serine-metalloprotease. Zymography revealed the presence of four distinct keratinases (Mr ~ 100, 62.5, 36.5 and 25 kDa) indicating its multiple forms. NMR and mass spectroscopic studies confirmed the presence of 18 free amino acids in the feather hydrolysates. Changes in feather keratin brought about by the keratinase action were studied by X-ray diffraction (XRD) and spectroscopic (FTIR, Raman) analyses, which showed a decrease in the total crystallinity index (TCI) (1.00-0.63) and confirmed the degradation of its crystalline domain. Scanning electron microscopy (SEM) revealed the sequential structural changes occurring in the feather keratin during degradation. Present study explored the use of keratinolytic potential of the newly isolated B. velezensis NCIM 5802 in chicken feather degradation and also, unraveled the underlying keratin hydrolysis mechanism through various analyses.

Molecular insight into Aspergillus oryzae ß-mannanase interacting with mannotriose revealed by molecular dynamic simulation study.

Fungal ß-mannanases hydrolyze ß-1, 4-glycosidic bonds of mannans and find application in the generation of mannose and prebiotic mannooligosaccharides (MOS). Previously, a MOS generating ß-mannanase from Aspergillus oryzae MTCC 1846 (ßManAo) was characterized and its structural and functional properties were unraveled through homology modeling and molecular dynamics in this study. The ßManAo model was validated with 92.9% and 6.5% of the residues found to be distributed in the most favorable and allowed regions of the Ramachandran plot. Glu244 was found to play a key role in the interaction with mannotriose, indicating conserved amino acids for the catalytic reaction. A detailed metadynamic analysis of the principal components revealed the presence of an α8-helix in the C-terminus which was very flexible in nature and energy landscapes suggested high conformation sub-states and the complex dynamic behavior of the protein. The binding of the M3 substrate stabilized the ß-mannanase and resulted in a reduction in the intermediate conformational sub-states evident from the free energy landscapes. The active site of the ß-mannanase is mostly hydrophilic in nature which is accordance with our results, where the major contribution in the binding energy of the substrate with the active site is from electrostatic interactions. Define Secondary Structure of Proteins (DSSP) analysis revealed a major transition of the protein from helix to ß-turn for binding with the mannotriose. The molecular dynamics of the ßManAo-mannotriose model, and the role and interactions of catalytic residues with ligand were also described. The substrate binding pocket of ßManAo was found to be highly dynamic and showed large, concerted movements. The outcomes of the present study can be exploited in further understanding the structural properties and functional dynamics of ßManAo.

Recent Developments in Industrial Mycozymes: A Current Appraisal.

Fungi, being natural decomposers, are the most potent, ubiquitous and versatile sources of industrial enzymes. About 60% of market share of industrial enzymes is sourced from filamentous fungi and yeasts. Mycozymes (myco-fungus; zymes-enzymes) are playing a pivotal role in several industrial applications and a number of potential applications are in the offing. The field of mycozyme production, while maintaining the old traditional methods, has also witnessed a sea change due to advents in recombinant DNA technology, optimisation protocols, fermentation technology and systems biology. Consolidated bioprocessing of abundant lignocellulosic biomass and complex polysaccharides is being explored at an unprecedented pace and a number of mycozymes of diverse fungal origins are being explored using suitable platforms. The present review attempts to revisit the current status of various mycozymes, screening and production strategies and applications thereof.

Purification of Aspergillus tamarii mycelial fructosyltransferase (m-FTase), optimized FOS production, and evaluation of its anticancer potential.

In the present study, generation of prebiotic fructooligosaccharides (FOS) using Aspergillus tamarii FTase was optimized by applying response surface methodology. Optimal FOS (251 g L-1 ) was generated at 28.4°C, pH 7.0 and 50% (w/v) sucrose leading to 1.97-fold yield enhancement. The m-FTase was purified using ultrafiltration followed by HiTrap Q HP anion exchange chromatography resulting in 2.15-fold purified FTase with 12.76 U mg-1 specific activity. Purified FTase (75 kDa) had Km and Vmax values of 1049.717 mM and 2.094 µmol min-1  mg-1 , respectively. FOS incorporation led to upregulation of caspase 3, caspase 9, and Bax genes suggesting mitochondrial apoptosis activation in cancer cells. The study describes characteristics of purified FTase from A. tamarii, production optimization of FOS and unravels the role of FOS in anticancer activity against HT-29 cells. PRACTICAL APPLICATION: This study provides detailed insights of kinetic and thermodynamic characteristics of purified FTase, a prebiotic FOS-generating enzyme. Moreover, the role of the apoptotic genes involved in anticancer activity, and the prebiotic potential of FOS is also investigated. These findings are important in the context of FOS applications, and the optimized production strategies make it useful for industrial application.

Heterologous expression and molecular modelling of L-asparaginase from Bacillus subtilis ETMC-2.

Bacterial L-asparaginase is the key therapeutic enzyme in cancer therapy and is also witnessing demand as a food processing aid. In this study, L-asparaginase of newly isolated Bacillus subtilis ETMC-2 was cloned and over-expressed in Escherichia coli as an active soluble protein using ligation independent cloning strategy. The molecular mass was estimated to be 40 kDa and was optimally active at 50 °C. Zymography revealed that the enzyme was active in homo-tetramer state (~160 KDa). The encoded protein after BLASTp analysis on NCBI showed 99.73% similarity with L-ASNase that of Bacillus sp. Physico-chemical properties were predicted using Protparam leading to categorization of the enzyme as a stable protein with an instability index (II) of 19.02. The calculated aliphatic index (85.44) indicated the high thermal stability of the protein with GRAVY value of -0.317. Protein-Ligand docking revealed that the residues Thr89, Thr121, and Asp122 were fundamental in protein-ligand complexation. After homology modelling, model validation was performed using Ramachandran plot, VERIFY3D, and RMSD. The paper describes cloning, heterologous expression, catalytic characteristics and physico-chemical properties of the type II B. subtilis L-ASNase.

Hemicellulose-Derived Oligosaccharides: Emerging Prebiotics in Disease Alleviation.

The gut microbiota in the human body is an important component that plays a pivotal role in the ability of the host to prevent diseases and recover from these diseases. If the human microbiome changes for any reason, it affects the overall functioning of the host. Healthy and vigorous gut microbiota require dietary fiber supplementation. Recently, oligosaccharides have been found to play a significant role in the modulation of microbiota. Several such oligosaccharides, i.e., xylooligosaccharides (XOS), mannooligosaccharides (MOS), and arabino-xylooligosaccharides (AXOS), are derived from hemicellulosic macromolecules such as xylan, mannan, and arabino-xylan, respectively. These oligosaccharides serve as substrates for the probiotic production of health-promoting substances (short-chain fatty acids, branched chain amino acids etc.), which confer a variety of health benefits, including the prevention of some dreaded diseases. Among hemicellulose-derived oligosaccharides (HDOs), XOS have been largely explored, whereas, studies on MOS and AXOS are currently underway. HDOs, upon ingestion, help reduce morbidities by lowering populations of harmful or pathogenic bacteria. The ATP-binding cassette (ABC) transporters are mainly utilized for the uptake of oligosaccharides in probiotics. Butyrate generated by the selective fermentation of oligosaccharides, along with other short-chain fatty acids, reduces gut inflammation. Overall, oligosaccharides derived from hemicelluloses show a similar potential as conventional prebiotics and can be supplemented as functional foods. This review summarizes the role of HDOs in the alleviation of autoimmune diseases (inflammatory bowel disease, Crohn's disease), diabetes, urinary tract infection, cardiovascular diseases, and antimicrobial resistance (AMR) through the modulation of the gut microbiota. The mechanism of oligosaccharide utilization and disease mitigation is also explained.

Production, properties, and applications of fructosyltransferase: a current appraisal.

BACKGROUND: Fructosyltransferases (FTases) are drawing increasing attention due to their application in prebiotic fructooligosaccharide (FOS) generation. FTases have been reported to occur in a variety of microorganisms but are predominantly found in filamentous fungi. These are employed at the industrial scale for generating FOS which make the key ingredient in functional food supplements and nutraceuticals due to their bifidogenic and various other health-promoting properties. SCOPE AND APPROACH: This review is aimed to discuss recent developments made in the area of FTase production, characterization, and application in order to present a comprehensive account of their present status to the reader. Structural features, catalytic mechanisms, and FTase improvement strategies have also been discussed in order to provide insight into these aspects. KEY FINDINGS AND CONCLUSIONS: Although FTases occur in several plants and microorganisms, fungal FTases are being exploited commercially for industrial-scale FOS generation. Several fungal FTases have been characterized and heterologously expressed. However, considerable scope exists for improved production and application of FTases for cost-effective production of prebiotic FOS.HIGHLIGHTSFructosyltrasferase (FTase) is a key enzyme in fructo-oligosaccharide (FOS) generationDevelopments in the production, properties, and functional aspects of FTasesMolecular modification and immobilization strategies for improved FOS generationFructosyltransferases are innovation hotspots in the food and nutraceutical industries.

Exo-inulinase production from Aspergillus fumigatus NFCCI 2426: purification, characterization, and immobilization for continuous fructose production.

Aspergillus fumigatus was found to produce thermostable exo-inulinase (EC 3.8.1.80; 38 U/ml) on inulin-rich infusions. Exo-inulinase (14.6 U/mg) was immobilized on glutaraldehyde activated Ca-alginate beads for continuous generation of fructose by hydrolyzing sucrose, chicory, and dandelion substrates. Immobilization of enzyme was confirmed by microscopic and spectroscopic techniques. The exo-inulinase was purified using ion-exchange (1.30-folds) and size-exclusion chromatography (2.71-folds). The purified exo-inulinase showed 64 kDa band on gel and was optimally active at 60 °C and pH 6.0. Kinetic constants, Km and Vmax of purified exo-inulinase, were 5.88 mM and 1.66 µM/min, respectively, and its relative activity was found to be enhanced (125.8%) in the presence of calcium ion. Immobilized preparation was utilized for continuous generation of fructose from chicory juice (26 to 70%) and dandelion root extracts (16 to 24%) by recycling upto five cycles, respectively. In comparison to other sweeteners, such as sucrose, fructose is considered as a healthy alternative. The present study demonstrated the use of immobilized exo-inulinase in continuous generation of fructose from some underutilized plant sources that can be used in food industry. PRACTICAL APPLICATION: Thermostable exo-inulinase produced by A. fumigatus was immobilized on calcium alginate matrix and was employed for continuous hydrolysis of chicory juice and dandelion root extract for generation of fructose syrup.

Production of mannooligosaccharides from various mannans and evaluation of their prebiotic potential.

Aspergillus quadrilineatus endo-ß-mannanase effectively degraded konjac glucomannan (66.09% w/v), copra meal (38.99% w/v) and locust bean galactomannan (20.94% w/v). High performance liquid chromatography (HPLC) analysis of KG hydrolysate indicated its mannooligosaccharides (MOS) content (656.38 mg/g) with high amounts of DP 5 oligosaccharide. Multi-scale characterization of mannan hydrolysate was done using FTIR and 13C NMR which revealed α and ß form of galactose or glucose in MOS, respectively. CM and LBG hydrolysates (1 mg/mL) have shown cytotoxic effect and reduced cell viability of Caco-2 cells by 45% and 62%, respectively. MOS DP (1-4) derived from LBG supported better Lactobacilli biofilm formation as compared to KG hydrolysate containing high DP MOS (5-7). Lactobacilli effectively fermented MOS to generate acetate and propionate as main short chain fatty acids. Lactobacilli produced leucine, isoleucine and valine as branched chain amino acids when grown on LBG hydrolysate.

Deciphering effectual binding potential of xylo-substrates towards xylose isomerase and xylokinase through molecular docking and molecular dynamic simulation.

Xylooligosaccharides (XOS) such as xylobiose and xylotriose are prebiotics with important functions and relevance and the study of interaction mechanism between these substrate and their respective enzymes has scope and applications. Thus, the present study aimed to decipher the interaction mechanisms of xylose isomerase (XylA) and xylokinase (XylB) towards their xylo-substrates namely xylobiose and xylotriose by computational modeling and molecular dynamic simulation studies. The three-dimensional structures of XylA and XylB, not available in their native forms, were predicted, energy minimized and validated by various computational biology tools and software. The binding mechanisms of xylobiose and xylotriose towards XylA and XylB were modeled by molecular docking and the stability of the docked complexes was confirmed by molecular dynamic (MD) simulation. The current study suggested that the theoretical models of XylA and XylB possessed good stereo-chemical validity, structural stabilities and minimum energy conformers. The molecular docking studied showed that xylotriose showed better binding interactions to XylA than xylobiose and xylobiose showed better binding interaction to XylB than xylotriose with ideal root mean square deviation (RMS), minimum binding energy (kcal/mol), hydrogen bonding and weak interactions. The MD simulation confirmed the stabilities of the docked complexes predicted by docking studies. The study suggested that interactions between the probiotics and prebiotics and provides the novel insights in exploring synbiotics as functional foods towards their futuristic applications. [Formula: see text]HighlightsThis study deciphers the interactions of xylosubstrates to XylA and XylB.The XylA and XylB possessed ideal structural stability and stereochemistryXylotriose and Xylobiose showed significant interactionsThe interactions of Xylotriose-XylA and Xylobiose-XylB were found stable in MD studies.Communicated by Ramaswamy H. Sarma.

Prebiotic mannooligosaccharides: Synthesis, characterization and bioactive properties.

Functional oligosaccharides are non-digestible food ingredients that confer numerous health benefits. Among these, mannooligosaccharides (MOS) are emerging prebiotics that have characteristic potential bio-active properties. Microbial mannanases can be used to break down mannan rich agro-residues to yield MOS. Various applications of MOS as health promoting functional food ingredient may open up newer opportunities in food and feed industry. Enzymatic hydrolysis is the widely preferred method over chemical hydrolysis for MOS production. Presently, commercial MOS is being derived from yeast cell wall mannan and is widely used as prebiotic in feed supplements for poultry and aquaculture. Apart from stimulating the growth of probiotic microflora, MOS impart anticancer and immunomodulatory effects by inducing different gene markers in colon cells. This review summarizes recent developments and future prospects of enzymatic synthesis of MOS from various mannans, their structural characteristics and their potential health benefits.

Production and characterization of keratinase by Ochrobactrum intermedium for feather keratin utilization.

A newly isolated bacterium producing 55.5 U/mL keratinase on feather meal minimal medium was identified as Ochrobactrum intermedium. Optimization of process parameters by one-variable-at-a-time (OVAT) approach (substrate concentration 0.5% w/v, inoculum size 5% w/v, pH 7.0, 200 rpm for 96 h at 40 °C) resulted in 2.1-fold increase in keratinase secretion (117 U/mL). Keratinase was optimally active at pH 9.0 and 40 °C and was stable at pH 9.0 and 60 °C for 120 min. Calcium ions enhanced keratinase activity (158%) significantly, while it was strongly inhibited by both PMSF and EDTA, indicating it to be a metallo-serine protease. Keratinase degraded native chicken feathers efficiently resulting in 97.9% weight loss along with release of 745.5 µg/mL soluble proteins and 4196.69 µg/mL amino acids. Feather hydrolysate generated by NKIS 1 exhibited significant anti-oxidant and free-radical scavenging activity (90.46%). The present study revealed that O. intermedium NKIS 1 has potential applications in the biodegradation of chicken feathers and the value-addition of poultry waste.

Characterization of biogenically synthesized silver nanoparticles for therapeutic applications and enzyme nanocomplex generation.

The present study describes green synthesis of silver nanoparticles (AgNPs) and inulin hydrolyzing enzyme nanocomplexes (ENC) using Azadirachta indica (Ai) and Punica granatum (Pg) leaf extracts. Surface topology and physico-chemical characteristics of AgNPs were studied using surface plasmon resonance (SPR), FTIR, SEM, AFM and EDX analyses. Particle size analysis using dynamic light scattering and AFM studies revealed that Ai-AgNPs (76.4 nm) were spherical in shape having central bigger nano-regime with smaller surroundings while Pg-AgNPs (72.1 nm) and ENCs (Inulinase-Pg-AgNPs ~ 145 nm) were spherical particles having smooth surfaces. Pg-AgNPs exhibited significant photocatalysis of a thiazine dye, methylene blue. Both Ai- and Pg-AgNPs showed selective antibacterial action by inhibiting pathogenic Bacillus cereus, while the probiotic Lactobacillus strains remained unaffected. Ai-AgNPs showed potential anti-biofilm effect (30% viability) on B. cereus biofilms. Pg-AgNPs showed anti-cancer effect against human colon cancer cell lines (Caco-2) resulting in 40% cell death in 48 h. Enzymes (inulinase, L-asparaginase and glucose oxidase) were successfully immobilized onto nanoparticles together with the biogenic synthesis of AgNPs and recyclability of the Inulinase-Pg-AgNPs complex was demonstrated. The study elaborates characteristics of green synthesized nanoparticles and their potential applications as anti-cancer, antibacterial and antioxidant nano drugs that could be used in food and nutraceutical industries. Enzyme immobilization on AgNPs without any toxic cross-linker opens up newer possibilites in enzyme-nanocomplex research.

Characteristics and bioactive properties of mannooligosaccharides derived from agro-waste mannans.

Mannooligosaccharides (MOS) were derived using Aspergillus oryzae ß-mannanase (ManAo) from different mannan-rich agro-wastes, palm kernel cake (PKC), guar gum and copra meal (CM). Guar gum (GG) released higher amount of MOS (56.31% w/w) from which purification of mannobiose (0.68 mg) and mannotriose (1.26 mg) was demonstrated using size-exclusion chromatography. FTIR analysis of mannan hydrolysates showed characteristic peaks in 1200-900 cm-1 region indicating the presence of MOS. 1H &13C NMR spectra showed presence of anomeric sugar forms of MOS in different mannan hydrolysates. MOS from locust bean gum and guar gum had both α- and ß-anomers while PKC and CM had only α-anomer. Growth promotional activities of different MOS were demonstrated using two probiotic Lactobacilli. Besides, enzymatically derived MOS also showed metal (Fe2+) chelating and anti-oxidant activities, wherein best anti-glycating agent was evaluated as MOS from PKC. PKC derived MOS showed highest cytotoxicity (74.19%) against human colon adenocarcinoma cell line (Caco-2). This study demonstrated the prebiotic potential of agro-waste derived MOS and possibility of their utilization as a functional food ingredient.

Investigation of the internal structure and dynamics of cellulose by 13C-NMR relaxometry and 2DPASS-MAS-NMR measurements.

Internal structure and dynamics of commercial and natural cellulose were studied by measuring chemical shift anisotropy (CSA) parameters, and spin-lattice relaxation rate (1/T1) at each and every chemically different carbon nuclear site. CSA parameters were measured by 13C two-dimensional phase adjusted spinning sideband (2DPASS) cross-polarization magic angle spinning (CP-MAS) NMR experiment. Site specific spin-lattice relaxation time was measured by Torchia-CP method. Anisotropy parameters of C4 and C6 regions are higher than C1 and C235 regions and asymmetry of C4 line is lower than any other carbon site. The higher values of CSA parameters of C4 and C6 nuclei arise due to the rotation of O4-C4, C1-O4, O5-C5-C6-O6 and C4-C5-C6-O6 bonds at torsion angles ψ, Φ, χ and χ' respectively and the influence of interchain and intrachain hydrogen bondings. Two distinct peaks are also observed for C4 and C6 resonance line position-one peak arises primarily due to the nuclei in amorphous region and another one arises due to the same nuclei resides in paracrystalline region. The spin-lattice relaxation time and the CSA parameters are different at these two distinct peak positions of C4 and C6 line. Molecular correlation time of each and every chemically different carbon site was calculated with the help of CSA parameters and spin-lattice relaxation time. The molecular correlation time of the amorphous region is one order of magnitude less than the crystalline region. The distinction between amorphous and paracrystalline regions of cellulose is more vividly portrayed by determining spin-lattice relaxation time, CSA parameters, and molecular correlation time at each and every chemically different carbon site. This type of study correlating the structure and dynamics of cellulose will illuminate the path of inventing biomimetic materials.