Molecular Weight Polypeptides Research Articles

Antioxidant polypeptides derived from pigeon pea (Cajanus cajan (L) Mill sp.) by enzymatic hydrolysis

Pigeon pea (Cajanus cajan (L) Mill sp.) seeds are rich sources of protein in the legume family and their consumption has been associated with the prevention of noncommunicated diseases, which is attributable to their content of bioactive components. Antioxidant protein hydrolysates were produced from pigeon pea protein isolate (PPI) by enzymatic hydrolysis using pancreatin and flavourzyme. The hydrolysates were analyzed for their physicochemical, molecular weight, amino acid composition, and in vitro antioxidant activities. The molecular weights of polypeptides in the hydrolysates were 8, 20, 25 and 48 kDa, which were determined after pancreatin or flavourzyme hydrolysis of the protein isolate for 4 h. Pancreatin-hydrolyzed pigeon pea protein (PPHP) contained high hydrophobic amino acids, especially isoleucine, leucine and valine, which were related to the high content of aromatic amino acids. The hydrolysates obtained from flavourzyme hydrolysis of pigeon pea proteins (PPHF) presented significantly higher capacities to scavenge ABTS˙+ and reduce Fe3 + better than that of PPI, while the PPI exhibited strong DPPH scavenging (98.4 mg trolox equivalent antioxidant capacity). The results indicated that the partial hydrolysis for PPI provided medium to high molecular weight of peptides. Therefore, PPHF could be a promising source of bioactive peptides and a potential ingredient for the formulation of functional foods against oxidative stress

Investigation of the Effectiveness of Photo Deprotection of Polypeptides in Solution and within the Core of Miniemulsion-Derived Nanoparticles.

Homopolymerization of ortho-nitrobenzyl (oNB)-protected l-cysteine and l-glutamic acid was systematically studied in different solvents and at different monomer to initiator ratios, revealing the best reaction control in dimethylformamide (DMF) across a range of degrees of polymerization. In the subsequent ultraviolet (UV)-cleavage studies, it was found that quantitative deprotection upon UV exposure at 365 nm was not achievable for either of the homopolypeptides as confirmed by 1H NMR and UV/visible (UV/vis) analyses. While the poly(oNB-l-cysteine) deprotected more readily with no effect of the polypeptide molecular weight, lower molecular weight poly(oNB-l-glutamate) reached maximum deprotection faster than high molecular weight samples. This was further confirmed by the pH changes of the solution. When incorporated into the core of miniemulsion-derived nanoparticles, both oNB-protected copolypeptides were successfully deprotected as evident from a color change and a pH change in the case of poly(oNB-l-glutamate). However, the removal of the deprotection byproduct nitrosobenzaldehyde proved unsuccessful, which indicates a diffusion barrier caused by the nanoparticle's surfactant. The study provides insights and guidelines for the UV deprotection of polypeptides and demonstrates the ability to selectively UV-deprotect polypeptides in the confined space of a nanoparticle dispersion.

Plum blossom low molecular weight polypeptide protects HaCaT cells against UVB-induced oxidative damage in vitro and underlying mechanism.

Increasing amounts of ultraviolet radiation occur as ozone depletion causes the earth's ozone layer to be destroyed, making antioxidant efficacy a research hotspot. Previous studies on plum blossom have mostly focused on Volatile Oils, Flavonoids, Phenylpropanoids, and other compounds, whereas few studies have focused on low molecular weight polypeptide (LMWP) of plum blossom. This research provides a reference for the deep processing and utilization of plum blossom. (a) Plum blossom low molecular weight polypeptides protect HaCaT cells against UVB-induced oxidative damage in vitro and the underlying mechanism. (b) Improve the theoretical basis for the intense processing and utilization of plum blossom. The safe concentration of LMWP and the survival rate of HaCaT cells were determined using the CCK-8 experiment. The fluorescence intensity of reactive oxygen species (ROS) was identified using the dichlorofluorescin diacetate (DCFH-DA) method; Superoxide dismutase (SOD) and malondialdehyde (MDA) concentrations were measured in ruptured cells; Western blot analysis was used to examine the expression levels of three proteins: nuclear factor E2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), and benzoquinone oxidoreductase 1 (NQO-1). It was noted that a certain concentration of LMWP could promote cell proliferation. In oxidatively damaged HaCaT cells, SOD levels and survival rates were markedly reduced, but ROS and MDA levels were elevated. However, after treatment with LMWP, the survival rate of the cells and SOD levels were markedly increased, and the levels of ROS and MDA were markedly decreased. As shown by Western blotting, the model group exhibited lower levels of Nrf2, HO-1, and NQO-1 expression than the control group, whereas LMWP-treated cells had significantly higher levels of Nrf2, HO-1, and NQO-1 expression than their model-treated counterparts. LMMP can effectively protect HaCaT cells against oxidative damage in vitro induced by UVB, and the underlying mechanism is linked to the activation of the transcription factor Nrf2.

Sorghum proteins: Effect of extraction pH on physicochemical properties and emulsion formation

Extraction methods suitable for food applications should be studied to obtain new plant protein isolates. This study aimed to evaluate the effect of pH (8.0, 10.0, and 12.0) and temperature (20 and 40 °C) during alkaline extraction on the yield and functional and physicochemical characteristics of sorghum protein isolates and to test their ability to stabilize emulsions. The best extraction yield (58.52 %) was at pH 12.0 and 40 °C. The obtained isolates had protein concentration superior to 4-fold as compared to the raw material. Electrophoresis showed mainly prolamins, with some globulin, glutelin, and higher molecular weight polypeptides (>250 kDa). Sorghum protein isolate obtained at pH 12.0 had improved solubility (64.77 %) compared to the isolates obtained at pH 8.0 (14.50 %) and pH 10.0 (17.68 %). Emulsions with 70 % (w/w) of oil showed no phase separation during storage, and those produced with the isolate obtained at pH 12.0 were more stable, with smaller droplet sizes after the 7-day storage (25.17–44.77 μm), lower creaming index, higher emulsion stability index (ESI), and less flocculation. The study demonstrated the functional ability of sorghum protein isolates obtained by alkaline extraction to form concentrated oil-in-water emulsions, avoiding using organic solvents.

Effect of Molecular Weight on the Structural and Emulsifying Characteristics of Bovine Bone Protein Hydrolysate.

The emulsifying capacity of bovine bone protein extracted using high-pressure hot water (HBBP) has been determined to be good. Nevertheless, given that HBBP is a blend of peptides with a broad range of molecular weights, the distinction in emulsifying capacity between polypeptide components with high and low molecular weights is unclear. Therefore, in this study, HBBP was separated into three molecular weight components of 10-30 kDa (HBBP 1), 5-10 kDa (HBBP 2), and <5 kDa (HBBP 3) via ultrafiltration, and the differences in their structures and emulsifying properties were investigated. The polypeptide with the highest molecular weight displayed the lowest endogenous fluorescence intensity, the least solubility in an aqueous solution, and the highest surface hydrophobicity index. Analysis using laser confocal Raman spectroscopy showed that with an increase in polypeptide molecular weight, the α-helix and β-sheet contents in the secondary structure of the polypeptide molecule increased significantly. Particle size, rheological characteristics, and laser confocal microscopy were used to characterize the emulsion made from peptides of various molecular weights. High-molecular-weight peptides were able to provide a more robust spatial repulsion and thicker interfacial coating in the emulsion, which would make the emulsion more stable. The above results showed that the high-molecular-weight polypeptide in HBBP effectively improved the emulsion stability when forming an emulsion. This study increased the rate at which bovine bone was utilized and provided a theoretical foundation for the use of bovine bone protein as an emulsifier in the food sector.

Detection of IgG Anti-Giardia duodenalis Antibodies in Sera by Indirect Immunofluorescence and Western Blotting Assays.

Serological assays are alternative laboratory tools for the diagnosis of parasitic infections. The aim of this work was to evaluate the performance of the indirect fluorescent antibody test (IFAT) and Western blotting (WB) for the detection of IgG anti-Giardia antibodies in human sera. Sera from individuals infected with Giardia duodenalis, other parasites or non-parasitized were selected for serological assays. Ninety-seven sera were tested by IFAT at 1:20 and 1:40 dilutions and of these, 40 samples were also analyzed by WB. The sensitivity and specificity of the IFAT was 97% and 46.9% at 1:20 sera dilution, and 39.4% and 59.4% at 1:40 sera dilution. The low molecular weight polypeptides fractions of 25kDa, 27-31kDa and 45-55kDa were the most frequently identified by the sera of individuals infected with G. duodenalis, along with low cross-reactivity, presenting an individual sensitivity of 42.8%, 50.0% and 57.1%, and specificity of 83.3%, 83.3% and 91.7%, respectively. The highest overall sensitivity of WB (85.7%) was based on the immunoreactivity of sera with at least one of those proteins. The concordance between the detection of G. duodenalis in feces by microscopy and the WB results was considered substantial (Kappa = 0.61). Constant exposure to Giardia infection throughout a lifetime can maintain high levels of specific antibodies in serum, even without active infection. Moreover, proteins found in intestinal amoebas may hinder the serological diagnosis of giardiasis in endemic areas due to cross-reactivity, which can be partially solved using Giardia low molecular weight proteins.

A combination of Sephadexes for the milk whey protein fractions isolation

Whey proteins perform important biological functions. They can also be a source of numerous natural bioactive peptides that have a positive effect on various physiological systems of the body. For research and usage of this phenomenon, the question of these proteins isolating with saving of their structure and biological functions is relevant. Considering the significant difference in molecular weights, gel filtration is a promising method. The purpose of the study was the fractionation of milk whey proteins using gel filtration with a combination of different dextran gels. We used in the work milk whey proteins after isoelectric precipitation of casein and isolation of low molecular weight peptides by gel filtration on Sephadex G-25. The first gel filtration of the whey protein preparation was performed on a column with Sephadex G-150. For further fractionation were used three sectors from the first two chromatographic peaks obtained by gel filtration on Sephadex G-150. The first peak contains high molecular fractions of proteins eluting with a volume close to the free volume of the chromatographic column. The second asymmetric peak consists mainly of β-lactoglobulin and α-lactalbumin mixture. The third peak includes low molecular weight polypeptides and peptides that are not fixed in a polyacrylamide gel. The combined chromatographic fractions of three sectors from the first two chromatographic peaks were re-fractionated on a G-100 column. Electrophoretic analysis of chromatographic fractions after repeated chromatography of milk whey proteins confirmed the feasibility of choosing a certain sequence of sephadex. At the same time, the yield of β-lactoglobulin fraction increases by 12 ± 1 %, and α-lactalbumin by 9 ± 1 % compared to the results obtained by repeated gel filtration on one Sephadex (G-100). The degree of purification of β-lactoglobulin and α-lactalbumin, according to the densitometry, was 93 ± 5 % and 77 ± 4 %, respectively.

Anti-cancer Potential of Pleurotus Mushroom: Detailed Insight on the Potential Bioactive Molecules, In vitro-In vivo Studies, and Formulation

Abstract: Early mushrooms were categorized under functional food/ nutritional food. However, later on, an increasing number of scientific studies strongly support their role in disease prevention and suppression or remission of a diseased state. Mycotherapy of cancer, a new promising field, can deal with anti-cancerogenic agents derived from mushrooms. Rich in nutritive value, undemanding cultivation conditions, and with an army of health-promoting bioactive molecules, collectively makes Pleurotus mushroom ideal for a researcher to investigate the anticancer potential. The present review is a literature survey on electronic search by two database search engines: Science direct and Pub med on anticancer potential of Pleurotus species until 2021. This data profiling will fast track information regarding the in vitro and in vivo anticancer activity of different types of Pleurotus species, along with identifying the bioactivemolecules responsible for anticancer potential with their underlying mechanism of action. Resultant findings from the electronic search revealed that till 2021, nearly 13 species of Pleurotus mushroom have been studied as anticancer potential. The biomarkers responsible for activity are mostly higher molecular weight molecules, comprising polysaccharides, polypeptides, proteins, lectins, and enzymes. The lower molecular weight molecules like terpenoids, sterols, and phenolic compounds are less explored and untapped. The main underlying mechanism for the anticancer activity of Pleurotus mushrooms is the induction of the mitochondria intrinsic pathway. For anticancer, Pleurotus mushrooms are widely formulated as metal nanoparticles. Altogether, with this detailed insight may impart the researcher a path to be addressed, thus driving mass attention to identify novel,effective, and safer anticancer potential biomarker.

Insights into the growth parameters, mineral composition, protein and UHPLC–QTOF–LC/MS‐based non‐targeted metabolomic fingerprints of wheatgrass as a function of photoperiod and temperature

SummaryWheatgrass juice powder (WJP) obtained from four Indian wheat varieties grown under different photoperiod and temperature conditions were examined for growth parameters, chlorophyll content, mineral composition, protein and metabolomic profile. The percentage yield and total chlorophyll content of WJP varied from 2.5% to 9.12% and 1.08 to 4.76 mg g−1, respectively. The WJP obtained from PBW‐752 showed the highest yield and total chlorophyll content. The mineral composition (Na, K, Ca and Mg) of WJP also showed variation with different photoperiod and temperature conditions. The electrophoretic pattern of total soluble proteins of WJP showed variability in the accumulation of high and low molecular weight polypeptides against different photoperiod and temperature conditions. The comprehensive metabolites profile of WJP was analysed by UHPLC–QTOF–liquid chromatography/mass spectrometry. Based on the retention times and m/z values, 1012 feature peaks in positive ionisation mode were detected. The metabolomic profile of WJP revealed 180 different classes of primary and secondary metabolites.

The Study of Type I Collagen by Immunoblotting in Samples of Bone-Plastic Biomaterials

The type I collagen was studied in samples of two types of osteoplastic materials produced in the Biotech Research Institute of the Samara State Medical University using immunoblotting. The demineralized samples used in the work were compact bone powder and crushed material of human cancellous bone tissue. Collagen and its polypeptides were separated in a 5% polyacrylamide gel with 3.6 M urea according to the method of Hayashi and Nagai (1979). The advantage of the method is the separation under these conditions of type I and III collagen, as well as the α1(I) and α2(I) chains of type I collagen. Immunoblotting was carried out by diffusion method according to the method of Towbin et al. (1979) using nitrocellulose membranes (Santa Cruz, USA). Primary goat polyclonal antibodies to denatured collagen, 1:500 dilution (Millipore) were used. Peroxidase-conjugated secondary antibodies (mouse vs. goat), 1:80000 dilution (Sigma) were used also. It has been established that the bulk of the compact bone protein is localized between the α1- and α2-fractions of collagen. In samples of cancellous bone tissue, a molecular reduction of the protein is noted. Protein macromolecules with a gradually decreasing molecular weight and low molecular weight polypeptides migrating in the gel with a wide front up to the indicator line are detected. Due to the low specificity of osteoblast integrins in regenerating bone tissue, collagen polypeptides, as well as protein molecules retained in implants, can act as inducers of synthetic processes occurring in osteoblast nuclei. Protein fragmentation products in the implant can act as signaling molecules that trigger cascades of enzymatic reactions and intracellular signaling pathways.

Oligonol ameliorates liver function and brain function in the 5 × FAD mouse model: transcriptional and cellular analysis.

Alzheimer's disease (AD) is a common neurodegenerative disease worldwide and is accompanied by memory deficits, personality changes, anxiety, depression, and social difficulties. For treatment of AD, many researchers have attempted to find medicinal resources with high effectiveness and without side effects. Oligonol is a low molecular weight polypeptide derived from lychee fruit extract. We investigated the effects of oligonol in 5 × FAD transgenic AD mice, which developed severe amyloid pathology, through behavioral tests (Barnes maze, marble burying, and nestle shredding) and molecular experiments. Oligonol treatment attenuated blood glucose levels and increased the antioxidant response in the livers of 5 × FAD mice. Moreover, the behavioral score data showed improvements in anxiety, depressive behavior, and cognitive impairment following a 2-month course of orally administered oligonol. Oligonol treatment not only altered the circulating levels of cytokines and adipokines in 5 × FAD mice, but also significantly enhanced the mRNA and protein levels of antioxidant enzymes and synaptic plasticity in the brain cortex and hippocampus. Therefore, we highlight the therapeutic potential of oligonol to attenuate neuropsychiatric problems and improve memory deficits in the early stage of AD.

Three novel antioxidant peptides isolated from C-phycocyanin against H2O2-induced oxidative stress in zebrafish via Nrf2 signaling pathway

BackgroundC-phycocyanin (C-PC), a phycobiliprotein from Spirulina platensis, has been confirmed to be an effective antioxidant. Duing to the large molecular weight protein, C-PC is hardly absorbed in the human gut and easy coagulates into lumps. In light of this, highly pure, easy absorption, and small molecular weight polypeptides has won the attention in the recent past. However, there are few studies on the C-PC bioactive peptides. Thus, the objective of this study was find natural multifunctional antioxidant peptides from C-PC and demonstrate their mechanisms.MethodIn this study, novel antioxidant peptides from pancreatin hydrolysate of C-PC were isolated and purified by using a multi-bioassay-guided method. The DPPH and ABTS radical scavenging in vitro and antioxidant zebrafish model in vivo were used to evaluate the antioxidant activities. Furthermore, the underlying molecular mechanisms of these peptides were investigated by measuring the level of ROS, MDA, SOD, CAT and gene expression in Nrf2 signaling pathway.ResultsTotal three novel active peptides, MHLWAAK (Met-His-Leu-Trp-Ala-Ala-Lys), MAQAAEYYR (Met-Ala-Gln-Ala-Ala-Glu-Tyr-Tyr-Arg), and MDYYFEER (Met-ASP-Tyr-Tyr-Phe-Glu-Glu-Arg) were isolated and purified from pancreatin hydrolysate of C-PC. These synthesized peptides displayed high DPPH and ABTS radical scavenging ability. In addition, in a zebrafish model, the three peptides significantly protected zebrafish embryos from H2O2-induced oxidative injury without toxicity by inhibiting ROS generation, preventing MDA formation, and upregulating the activities of SOD and CAT. Further experiments showed that these peptides could significantly regulated oxidative stress via activating the Nrf2 signaling pathway.ConclusionThis study indicates that the antioxidant peptides from C-PC could serve as powerful antioxidants for preventing and treating various diseases associated with oxidative stress.

Effects of Phytochelatin-like Gene on the Resistance and Enrichment of Cd2+ in Tobacco.

Phytochelatins (PCs) are class III metallothioneins in plants. They are low molecular-weight polypeptides rich in cysteine residues which can bind to metal ions and affect the physiological metabolism in plants. Unlike other types of metallothioneins, PCs are not the product of gene coding but are synthesized by phytochelatin synthase (PCS) based on glutathione (GSH). The chemical formula of phytochelatin is a mixture of (γ-Glu-Cys)n-Gly (n = 2-11) and is influenced by many factors during synthesis. Phytochelatin-like (PCL) is a gene-encoded peptide (Met-(α-Glu-Cys)11-Gly) designed by our laboratory whose amino acid sequence mimics that of a natural phytochelatin. This study investigated how PCL expression in transgenic plants affects resistance to Cd and Cd accumulation. Under Cd2+ stress, transgenic plants were proven to perform significantly better than the wild-type (WT), regarding morphological traits and antioxidant abilities, but accumulated Cd to higher levels, notably in the roots. Fluorescence microscopy showed that PCL localized in the cytoplasm and nucleus.

Interfacial Properties of Pea Protein Hydrolysate: The Effect of Ionic Strength

The effect of a tryptic hydrolysis as well as the effect of ionic strength (0–0.4 M NaCl) was investigated on the oil/water interfacial properties of soluble pea protein hydrolysate (SPPH) at neutral pH and room temperature (20 ± 0.01 °C). SEC-MALS and SDS-Page analysis showed that tryptic hydrolysis created a lower molecular weight polypeptide mixture, whereas FTIR analysis and DSC thermograms demonstrated a more disordered and flexible structure. The bulk properties of SPPH were studied in terms of hydrodynamic diameter and turbidity, where higher particle size (+ ~13 nm) and turbidity were observed at 0.4 M NaCl. Regarding the interfacial properties, the surface activity of SPPH improved by increasing ionic strength, with maximum interfacial pressure (14.28 mN/m) at 0.4 M NaCl. Nevertheless, the addition of NaCl negatively affected the elasticity and strength of the interfacial film, where the sample without salt exhibited the highest dilatational and shear storage modulus in all the frequencies considered.

Insights into flavor and key influencing factors of Maillard reaction products: A recent update.

During food processing, especially heating, the flavor and color of food change to a great extent due to Maillard reaction (MR). MR is a natural process for improving the flavor in various model systems and food products. Maillard reaction Products (MRPs) serve as ideal materials for the production of diverse flavors, which ultimately improve the flavor or reduce the odor of raw materials. Due to the complexity of the reaction, MR is affected by various factors, such as protein source, hydrolysis conditions, polypeptide molecular weight, temperature, and pH. In the recent years, much emphasis is given on conditional MR that could be used in producing of flavor-enhancing peptides and other compounds to increase the consumer preference and acceptability of processed foods. Recent reviews have highlighted the effects of MR on the functional and biological properties, without elaborating the flavor compounds obtained by the MR. In this review, we have mainly introduced the Maillard reaction-derived flavors (MF), the main substances producing MF, and detection methods. Subsequently, the main factors influencing MF, from the selection of materials (sugar sources, protein sources, enzymatic hydrolysis methods, molecular weights of peptides) to the reaction conditions (temperature, pH), are also described. In addition, the existing adverse effects of MR on the biological properties of protein are also pointed out.

Metabolism Reactivation in Erythrocytes Cryopreserved with Polyethylene Glycol: Protein State and Reactive Oxygen Species Production

Production of reactive oxygen species (ROS) and protein state of membrane-cytoskeleton complex (MCC) in the erythrocytes, subjected to freeze-thawing with polyethylene glycol (PEG) and subsequently transferred into physiological conditions in vitro after cryoprotective agent removal were examined. Results of SDS-PAGE with β-mercaptoethanol showed a decrease in spectrin content in the MCC profile of cryopreserved erythrocytes. The using of diamide revealed an increase in the accessibility of –SH groups of spectrin for the reagent and an enhanced level of high molecular weight polypeptide complexes relative to the control. A decrease in the content of protein band 8 (peroxiredoxin) in the MCC of cryopreserved erythrocytes revealed by SDS-PAGE with β-mercaptoethanol is apparently associated with a change in its localization caused by an increased ROS production at the previous stages of cryopreservation. At the same time, the absence of significant changes in the ROS production relative to the control upon the metabolism reactivation in erythrocytes indicated the ability of cryopreserved cells to control the oxidative processes during short-term incubation.

Total and chloroplast proteins of the leaves of cultivated, population and wild sunflower varieties cultivated under thermic stress

Sunflower (Helianthus annus L) cultivation is affected by periods of severe drought that affect the growth and yield of sunflower crops. Wild sunflower species have brought many agronomically important traits to cultivated sunflower by quickly allowing them to undergo biotic and abiotic changes in their environment. Plants have developed several mechanisms that would enable them to tolerate high temperatures related to thermotolerance at the biochemical and metabolic levels. The present study aimed to highlight the variability of total and chloroplast proteins extracted from the wild and populations of sunflower leaves grown under different thermal stresses. The total proteins extracted from controlled and thermic stress leaves, characterized by SDS page were similar except polypeptides of molecular weight (MW) 42 kDa, 35 kDa, 31 kDa and 13.5 kDa which showed variability of sunflower varieties studied. Under thermic stress, the MW of chloroplast proteins was similar in the H petiolaris fallax and H praecox runyonni varieties. The protein markers of wild sunflower species revealed in response to thermal stresses contribute to the improvement of sunflowers in the face of environmental challenges.

TREATMENT OF HUMAN SKIN BURNS THROUGH USING TILAPIA SKIN

Burns are medical conditions that are the fifth major reason behind non-fatal and adult injuries due to compulsiveness and a lack of risk calculation ability. 1.2 In Pakistan, 2500 children suffer serious burns that necessitate medical attention each year, with 15,000 requiring hospitalizations. The WHO (World Health Organization) has revealed in the reports that child burn mortality is greater (seven times) in countries with low and middle-income backgrounds compared to those with high incomes. Polypeptides of varied molecular weights were discovered in MCPs. These MCPs come from Nile tilapia’s skin with the help of enzyme-aided hydrolysis, with polypeptides with a molecular weight smaller than 5kDa accounting for 99.1 percent of the total. The key molecular conformations within MCPs were casual coil, according to FTIR. The MCPs application was done in the quantity of 50g/ml. The treatment significantly affected scratch closure in an in vitro scratch assay. MCPs improve wound healing in child burn skin with a deep partial-thickness scald wound. As a result, it was concluded that the MCPs derived from Nile tilapia‘s skin have promising wound care effects and results.

Peptides and low molecular weight polypeptides of Azadirachta indica seeds as new weapons against cancer cells and superbugs

BackgroundIn Ayurvedic practice, neem is an immensely important medicinal plant that's been part of traditional medications dating back to ˂ 5000 years. Its botanical name being A. indica while it is known as Nimba in Sanskrit. Prior to written records, all the parts of neem were used to treat and cure various ailments, infections, fevers, etc. Such wide range of application has led to it being termed “the village pharmacy.” The current study reports for the first time extraction and biological activity evaluation of these AMPs and polypeptides derived from the seeds of A. indica. Materials and methodThe present study intends to be the first to evaluate the antimicrobial and antitumoral properties of peptides and polypeptides on cancer cell lines from the total protein extracted from neem plant seeds by means of cell and molecular biology approaches. Protein extraction and precipitation was performed applying our optimized/standardized protocols. The antimicrobial activity was assayed efficiently using PAG-ADA method. The anticancer property of the extracted protein was detected by MTT assay, while MALDI-TOF/TOF and FTIR were performed to characterize the structure of these AMPs and polypeptides. ResultsTwo standardized protein extraction procedures were employed and the protein obtained from these two procedures were 262.67 ± 6.12 and, 248.7 ± 9.49 mg/g of seeds, respectively. Our study reports two novel antimicrobial peptides, and four polypeptides extracted from the dried seeds of A. indica. Further, we confirmed the bactericidal activity of the peptides and polypeptides extracted from A. indica seeds using PAG-ADA techniques against six different human pathogens. Remarkably high zone of growth inhibition against MRSA (30.0 ± 1.52) mm was noted. On the other hand, the total protein extracted possessed excellent anticancer activity with low IC50 values of 33.46 ± 2.63 and 20.83 ± 1.60 μg/mL against HeLa cells and 6.94 ± 0.10 and 6.87 ± 0.90 μg/mL against BT549 cell lines at 24 and 48 h, respectively. ConclusionsAMPs and polypeptides extracted from seeds of the medicinal plant A. indica exhibited bactericidal activity against different bacterial pathogens. In addition, the extract possessed good anticancer activity against the cervical cancer and breast cancer cell lines. Therefore, these promising findings pave the way for identification of plant-based bioactives responsible for the anticancer and antimicrobial attributes.

Bifunctional Fluoroalcohol Catalysts Enabled Sustainable Synthesis of Poly(amino acid)s†

Main observation and conclusionA series of novel bifunctional single‐molecule hydrogen‐bonding organocatalysts based on fluorinated tertiary alcohol were synthesized to mediate the metal‐free polymerization of α‐amino acid N‐carboxyanhydride (NCA) monomer. Through the screening of catalysts, the polymerization catalyzed by the preferred bifunctional fluoroalcohol catalyst proceeded in a fast and controlled manner, affording high molecular weight polypeptide up to 35.2 × 104 Da with relatively narrow molecular weight distribution (Đ &lt; 1.20). A phenomenon of self‐accelerating effect of polymerization induced by α‐helical structure of polypeptides was observed, and a possible polymerization pathway has been discussed.