Research Publications (Applied Sciences)

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12th International Conference on Sustainable Waste Management
(2022-12-02) Nibedita, Nath; Subhendu, Chakraborthy; Narsimha, Golla; Adam, Jamila Khatoon; Krishna, Suresh Babu Naidu
Today, nanotechnology generates a significant amount of interest among researchers as a result of the vast array of applications it provides for addressing various aspects of the eco-system. Additionally, it enables researchers to traverse the boundaries of a more specialised area of study than an already well-established one. It is an interdisciplinary field of study that focuses on the production and manipulation of nanoscale materials via scaling down the particle size scale from micrometres to nanometers (1–100 nm). They provide excellent options in the fields of health, industry, and medicine as they present a new vision for the treatment of medical conditions thanks to the fact that the particle size may be reduced, which gives them a distinct prospective characteristic. Researchers continue to be interested in finding new uses for metal nanoparticles (NPs) as the field of nanotechnology advances since these particles display distinctive properties. The public is interested in several different types of metal nanoparticles, including silver NPs. Synthesized silver nanoparticles (AgNPs) can be used in a wide variety of contexts, such as spectrally selective coatings for the absorption of solar energy, as intercalation material for electrical batteries, as optical receptors, as catalysts in chemical processes, and so on. Antibacterial and antifungal properties are only two of the biological uses of silver nanoparticles that have been the subject of much research. AgNPs are known to be cytotoxic to both normal and cancer cells in mammals, and the modalities of interactions of AgNPs have been examined in a variety of prokaryotic and eukaryotic systems. AgNPs are known to be cytotoxic to both normal and cancer cells in humans. The cytotoxic effects of silver ions have been seen and documented in a variety of cell lines. Silver nanoparticles have become important research topics due to the numerous applications they have in the fields of industry, agriculture, and biomedicine, as well as their excellent anti-bacterial, anti-fungal, anti-oxidant, anti-inflammatory, anti-viral, anti-coagulant, and photo-catalytic properties due to their chemical stability and good biocompatibility. The most important focus of this review is on recent advancements and trends in the field of AgNPs for use in biomedical applications. Keywords: Antimicrobial, silver nanoparticles, synthesis, biomedical applications, nanotechnology
Acceptance of a ready-to-use supplementary food by stable HIV-treated and HIV and tuberculosis (co-infected)-treated patients
(NISC (Pty) Ltd and Taylor & Francis, 2014) Pillay, K.; Siwela, M.; Feldman, F.J.; Amonsou, Eric Oscar; Mabaso, B.P.
Objectives: The objective of the study was to determine consumer acceptance and perceptions of a ready-to-use supplementary food (RUSF) by subjects treated for human immunodeficiency virus (HIV) and HIV and tuberculosis (co-infected subjects). Design: A cross-sectional study was conducted. Subjects: One hundred and thirty-nine stable HIV-treated and HIV and tuberculosis (co-infected)-treated patients participated in the study. Sixty-eight healthy subjects served as the control group. Setting: The setting was Northdale Hospital and Grey’s Hospital in Pietermaritzburg, KwaZulu-Natal. Outcome measures: Acceptance of the RUSF was assessed using a five-point facial hedonic scale by stable HIV-treated and HIV and tuberculosis (co-infected)-treated patients (n = 139) from Northdale Hospital and Grey’s Hospital in Pietermaritzburg, KwaZulu-Natal. Perceptions of the RUSF were determined through focus group discussions in which HIV-treated and HIV and tuberculosis (co-infected)-treated patients (n = 43) participated. Results: The overall acceptance of the RUSF was significantly associated with the health status of the subjects (p-value < 0.05). Overall, the product was liked by more than 90% of the HIV-treated and HIV and tuberculosis (co-infected)-treated individuals compared to 85% of the control group. More than 90% of the HIV-treated and HIV and tuberculosis (co-infected)-treated individuals liked the taste, compared to 87% of the control group. The colour and mouth feel were rated to be “good” by more than 80% of the HIV-treated and HIV and tuberculosis (co-infected)-treated group, compared to approximately 70% of the healthy group. Focus group discussions revealed that the subjects perceived the mouth feel of the RUSF to be “rough”, and that as a health supplement, the RUSF should be provided free of charge, or at a reasonable cost, at public health centres. Conclusion: The RUSF was found to be highly acceptable to stable HIV-treated and HIV and tuberculosis (co-infected)-treated subjects, although concern was raised about the mouth feel.
Advances in synthesis of biodiesel via enzyme catalysis : Novel and sustainable approaches
(Elsevier, 2015-01) Singh, Bhaskar; Mutanda, Taurai; Permaul, Kugen; Bux, Faizal; Guldhe, Abhishek
Biodiesel, a renewable fuel has a great potential in fulﬁlling an ever-increasing transport fuel demand. The enzymatic conversion process of feedstock oil to biodiesel is greener when compared to the conventional approach of chemical conversion due to mild reaction conditions and less wastewater generation. Lipases obtained from various microbial sources have been widely applied as catalysts for the conversion of oil to biodiesel. Biodiesel and glycerol obtained by enzymatic conversion have shown a higher purity as compared to that obtained by other conversion techniques. Enzymatic conversion of oil to biodiesel is less energy intensive because of milder reaction conditions and fewer puriﬁcation steps involved in processing. Lipases, due to their catalytic efﬁciency and speciﬁcity, have emerged as a great tool for converting a wide range of feedstock oils to biodiesel. This manuscript presents an overview of the use of enzymatic conversion for making biodiesel production sustainable and environmentally-friendly. The constraints of enzymatic conversion are the high cost of the enzyme and its inhibition by alcohol and glycerol. The possible solutions to overcome these constraints are discussed. Recent advances to develop an effective process for enzymatic conversion of feedstock oils into biodiesel are critically evaluated. Prospective and challenges in scaling up of this technology are also discussed.
Antimicrobial activity of plant phenols from Chlorophora excelsa and Virgilia oroboides
(Academic Journals, 2013-04-24) Padayachee, Thiriloshani; Odhav, Bharti
The anti-bacterial and anti-fungal activity of four aqueous plant extracts (1 x 104 µg/ml) of 2,3'4,5'-tetra hydroxy-4'-geranylstilbene (chlorophorin) and 3',4, 5' - trihydroxy - 4' - geranylstilbene (Iroko) from the tree Chlorophora excelsa and (6aR,11aR)-3-hydroxy-8,9-methylenedioxypterocarpan (Maackiain) and 7-hydroxy-4'-methoxyisoflavone (formononetin) from Virgilia oroboides were evaluated by the seeded agar overlay well diffusion method. The test organisms and bioautography used included: Bacillus coagulans, Streptococcus pneumoniae, Klebsiella pneumoniae, Escherichia coli, Mycobacteria tuberculosis, Aspergillus flavus and Fusarium verticilloides. Vancomycin, the drug of choice for these organisms was used as the control at 30 µg/ml. The extracts showed that chlorophorin at 1.95 µg/ml and Iroko at 3.125 and 6.25 µg/ml respectively were active in inhibiting the growth of S. pneumoniae and B. coagulans and not active against K. pneumoniae and E. coli. Maackiain; formononetin and formononetin acetate showed little activity against S. pneumonia, B. coagulans, K. pneumoniae and E. coli. None of the extracts showed activity against M. tuberculosis. Maackiain, formononetin, chlorophorin and Iroko inhibited F. vertiicilloides, maackiain being the most active compound. Formononetin, chlorophorin and Iroko inhibited A. flavus. A. flavus was most sensitive to chlorophorin and Iroko. The bioautography method confirmed these results and was attributed to the phenolic nature of the compounds.
Antimycobacterial, docking and molecular dynamic studies of pentacyclic triterpenes from Buddleja saligna leaves
(Taylor and Fancis Online, 2017) Singh, Alveera; Venugopala, Katharigatta Narayanaswamy; Khedr, Mohammed A.; Pillay, Mellendran; Nwaeze, Kenneth U.; Coovadia, Yacoob; Shode, Francis; Odhav, Bharti
Buddleja saligna (family Buddlejaceae) is a medicinal plant endemic to South Africa. Two isomeric pentacyclic triterpenes, oleanolic acid and ursolic acid, were isolated from the leaves of B. saligna using silica gel column chromatography. Compounds oleanolic acid and ursolic acid were subjected to derivatization with acetic anhydride in the presence of pyridine to obtain oleanolic acid-3-acetate and ursolic acid-3-acetate, respectively. The structures of these compounds were fully characterized by detailed nuclear magnetic resonance (NMR) investigations, which included 1H and 13C NMR. Molecular docking studies predicted the free binding energy of the four triterpenes inside the steroid binding pocket of Mycobacterium tuberculosis fadA5 thiolase compared to a reported inhibitor. Thus, their ability to inhibit the growth of M. tuberculosis was predicted and was confirmed to possess significant antimycobacterial activity when tested against Mycobacterium smegmatis, M. tuberculosis H37Rv (ATCC 25177), clinical isolates of multi-drug-resistant M. tuberculosis (MDR-TB) and extensively drug-resistant M. tuberculosis (XDR-TB) using the Micro Alamar Blue Assay. Ursolic acid was isolated from this plant for the first time.
Apoptosis in the human laryngeal carcinoma (HEp-2) cell line by Bulbine natalensis and B. Frutescens fractions
(IJBPR, 2012) Singh, Rishan; Reddy, Lalini
Many plants that belong to the genus Bulbine have compounds in their roots and leaves which are considered important for traditional treatments. The stems and roots of Bulbine species are believed to contain anticancer compounds such as anthraquinones, including chrysophanol and knipholone. However, in general, people utilise plants of the Bulbine genus for the treatment of rashes, itches, wounds, burns, cracked lips and cracked skin. This study assessed the effect of aqueous and organic fractions of Bulbine natalensis and Bulbine frutescens on the human laryngeal carcinoma cell line (HEp-2) for apoptosis. The MTT assay was used to determine the cytotoxicity of the fractions administered and to select fractions for analysis of bax and caspase-3 gene expression, which are induced during programmed cell death type 1, known as apoptosis. All of the B. natalensis fractions induced expression of caspase-3, while the tested B. frutescens aqueous root fractions failed to induce expression of caspase-3. The variation in bax gene expression indicated that HEp-2 cell death was due to apoptosis and other unknown forms of cell death that may or may not activate caspase-3 gene expression.
Azide-alkyne cycloaddition en route to 1H-1,2,3-triazole-tethered 7-chloroquinoline-isatin chimeras : synthesis and antimalarial evaluation
(Elsevier, 2013-04) Raj, Raghu; Singh, Pardeep; Singh, Parvesh; Gut, Jiri; Rosenthal, Philip J.; Kumar, Vipan
We describe the synthesis and antimalarial activities of 1H-1,2,3-triazole tethered 7-chloroquinoline-isatin hybrids. Activity against cultured parasites was dependent on the C-5 substituent of the isatin ring as well as the alkyl chain length between the isatin and 7-chloroquinoline moieties. Compound 8h, with an optimum alkyl chain length (n = 3) and a chloro substituent at the C-5 position of the isatin ring, displayed the best activity among the test compounds, with IC50 value of 1.21 μM against cultured W2-strain Plasmodium falciparum.
Biocatalytic and biological activities of cassia occidentalis mediated silver nanoparticles
(College of Graduate Studies, Walailak University, 2022-01-01) Singh, Shashika; Mohanlall, Viresh
Silver nanoparticles (AgNPs) were synthesized using the leaf extracts from Cassia occidentalis. The reactions were marked by a distinct colour change and the formation of AgNPs was monitored by measuring the UV-Vis spectra. The morphology and crystalline phase of the metal nanoparticles were determined using Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray analysis (EDX) and Fourier-Transform-Infrared Spectroscopy (FTIR). The biocatalytic activity of the AgNPs against nitrifying compounds was determined using 4-nitrophenol and 4-nitroalanine. The biological screening involved analyzing the AgNPs effectiveness against gram-negative and gram-positive bacteria (Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Bacillus cereus and Enterococcus faecalis). The AgNPs displayed minimal inhibition at low concentrations ranging from 25 to 50 μg/mL. The toxicity of the AgNPs was tested using the brine shrimp assay and was observed as non-toxic with a nearly zero mortality rate. The AgNPs exhibited an antioxidant potential of 70.90 % inhibition at 1000 µg/mL. C. occidentalis is noted as a potential bioresource for synthesizing AgNPs with applications as antibacterial, antioxidant and biocatalytic agents. HIGHLIGHTS The addition of Ag nanoparticles to C. occidentalis plant extracts resulted in the formation of AgNPs-C. occidentalis complexes The AgNPs-C. occidentalis complexes were characterized using Transmission Electron Microscopy, Scanning Electron Microscopy with EDX, UV-Vis spectrophotometry and IR spectroscopy These AgNPs-C. occidentalis complexes were very stable and showed antibacterial activity against a range of tested gram-positive and gram-negative bacteria at low doses, thus proving to be good antimicrobial agents The AgNPs-C. occidentalis complexes showed higher scavenging activity than leaf extracts of C. occidentalis. The AgNPs have increased catalytic ability for the reduction of 4-nitrophenol and 4-nitroalanine after a 30 min time interval GRAPHICAL ABSTRACT
Biodegradation of glycerol using bacterial isolates from soil under aerobic conditions
(Taylor and Francis, 2014) Raghunandan, Kerisha; Mchunu, Siphesihle; Kumar, Ashwani; Kumar, Kuttanpillai Santhosh; Govender, Algasan; Permaul, Kugen; Singh, Suren
Glycerol, a non-biodegradable by-product during biodiesel production is a major concern to the emerging biodiesel industry. Many microbes in natural environments have the ability to utilize glycerol as a sole carbon and energy source. The focus of this study was to screen for microorganisms from soil, capable of glycerol utilization and its conversion to value added products such as ethanol and 1,3-propanediol (1,3-PDO). Twelve bacterial isolates were screened for glycerol utilization ability in shake flask fermentations using M9 media supplemented with analytical grade glycerol (30 g/L) at various pH values (6, 7 and 8) and temperatures (30◦C, 35◦Cand 40◦C). Among these, six bacterial isolates (SM1, SM3, SM4, SM5, SM7 and SM8) with high glycerol degradation efficiency (>80%) were selected for further analysis. Highest level of 1,3-PDO production (15 g/L) was observed with isolate SM7 at pH 7 and 30◦C, while superior ethanol production (14 g/L) was achieved by isolate SM9 at pH 8 and 35◦C, at a glycerol concentration of 30 g/L. The selected strains were further evaluated for their bioconversion efficiency at elevated glycerol concentrations (50–110 g/L). Maximum 1,3-PDO production (46 g/L and 35 g/L) was achieved at a glycerol concentration of 70 g/L by isolates SM4 and SM7 respectively, with high glycerol degradation efficiency (>90). Three isolates (SM4, SM5 and SM7) also showed greater glycerol tolerance (up to 110 g/L). The isolates SM4 and SM7 were identified as Klebsiella pneumoniae and SM5 as Enterobacter aerogenes by 16S rDNA analysis. These novel isolates with greater glycerol tolerance could be used for the biodegradation of glycerol waste generated from the biodiesel industry into value-added commercial products.
Biogenic metallic nanoparticles as enzyme mimicking agents
(Frontiers Media SA, 2023-03) Ngcongco, Khanyisile; Krishna, Suresh Babu Naidu; Pillay, Karen
The use of biological systems such as plants, bacteria, and fungi for the synthesis of nanomaterials has emerged to fill the gap in the development of sustainable methods that are non-toxic, pollution-free, environmentally friendly, and economical for synthesizing nanomaterials with potential in biomedicine, biotechnology, environmental science, and engineering. Current research focuses on understanding the characteristics of biogenic nanoparticles as these will form the basis for the biosynthesis of nanoparticles with multiple functions due to the physicochemical properties they possess. This review briefly describes the intrinsic enzymatic mimetic activity of biogenic metallic nanoparticles, the cytotoxic effects of nanoparticles due to their physicochemical properties and the use of capping agents, molecules acting as reducing and stability agents and which aid to alleviate toxicity. The review also summarizes recent green synthetic strategies for metallic nanoparticles.
Biosynthesis and characterization methods of copper nanoparticles and their applications in the agricultural sector
(Elsevier, 2022-01-15) Reddy, Bhagavanth; Mangatayaru, Girija K.; D, Madhusudan Reddy; Krishna, Suresh Babu Naidu; Golla, Narasimha; Kamel A, Abd-Elsalam
This book provides information on the design and application of ecologically safe formulations, for protecting cultivated crops against insects and pathogen-causing diseases, plant science, antimicrobial applications and agroecosystem ...
Biosynthesis of palladium nanoparticles by using Moringa oleifera ﬂower extract and their catalytic and biological properties
(Elsevier, 2016) Anand, Krishnan; Tiloke, Charlette; Phulukdaree, Alisa; Ranjan, B.; Chuturgoon, Anil A.; Singh, S.; Gengan, Robert Moonsamy
The biosynthesis of nanostructured biopalladium nanoparticles (PdNPs) from an aqueous solution of crystalline palladium acetate is reported. For the synthesised PdNPs in solution, an agroforest biomass waste petal of Moringa oleifera derived bis-phthalate was used as natural reducing and biocapping agents. Continuous absorp-tion in the UV region and subsequent brown colour change conﬁrmed the formation of PdNPs. A strong surface plasmon peak for PdNPs occurred at 460 nm. PdNPs were characterized by SEM with EDX, FTIR, TEM and DLS. The chemical composition of the aqueous extract was determined by GC–MS coupled with FTIR and 1NMR. The cat-alytic degradation effect by PdNPs on industrial organic toxic efﬂuents p-nitrophenol (PNP) and methylene blue dye was monitored by UV Spectroscopy. On the other hand PdNPs catalysed the base mediated suzuki coupling reaction for biphenyl synthesis, in water. Moreover, PdNPs were found to be reusable catalysts. Toxicity studies of PdNPs showed that the death of brine shrimp to be b50%. Therefore, PdNPs displayed potential for further anti-cancer studies via tumour cell lines. The in vitro cytotoxicity evaluation of the extract capped nanoparticles was carried out using human lung carcinoma cells (A549) and peripheral lymphocytes normal cells by MTT cell via-bility assay. Also, PdNPs showed antibacterial activity against Enterococcus faecalis among the different tested strains, including Bacillus cereus, Staphylococcus aureus, Esherichia coli and Candida albicans, Candida utilis.
A brief review of secondary plant metabolites as anticancer agents
(COJ Reviews & Research, 2020-05-18) Mohanlall, Viresh; Naicker, Leeann
Plants have provided a source of medicine from the beginning of human history and are the core of modern medicine. Moreover, plant-based drug discovery has led to the development of various anticancer drugs (such as vincristine, vinblastine, etoposide, paclitaxel, camptothecin, topotecan and irinotecan). The use of botanical, photochemical, biological and molecular techniques have facilitated the discovery of novel secondary metabolites from native and indigenous plants that can inhibit the human topoisomerase II enzyme (target for anticancer drugs) and kill cancer cells. Therefore, the aim of this review was to further investigate the anticancer activity of secondary metabolites from native and indigenous plants and determine the classes of compounds that contributed towards its activity.
Cervical cytology as a diagnostic tool for female genital schistosomiasis : correlation to cervical atypia and Schistosoma polymerase chain reaction
(Cytopathology Foundation Inc with Wolters Kluwer, 2016-04-20) Pillay, Pavitra; van Lieshout, Lisette; Taylor, Myra; Sebitloane, Motshedisi; Zulu, Siphosenkosi Gift; Kleppa, Elisabeth; Roald, Borghild; Kjetland, Eyrun Floerecke
Background: Female genital schistosomiasis (FGS) is a tissue reaction to lodged ova of Schistosoma haematobium in the genital mucosa. Lesions can make the mucosa friable and prone to bleeding and discharge. Women with FGS may have an increased risk of HIV acquisition, and FGS may act as a cofactor in the development of cervical cancer. Objectives: To explore cytology as a method for diagnosing FGS and to discuss the diagnostic challenges in low-resource rural areas. The correlation between FGS and squamous cell atypia (SCA) is also explored and discussed. Cytology results are compared to Schistosoma polymerase chain reaction (PCR) in vaginal lavage and urine and in urine microscopy. Materials and Methods: In a clinical study, 394 women aged between 16 and 23 years from rural high schools in KwaZulu-Natal, South Africa, underwent structured interviews and the following laboratory tests: Cytology Papanicolaou (Pap) smears for S. haematobium ova and cervical SCA, real-time PCR for Schistosoma-specific DNA in vaginal lavage and urine samples, and urine microscopy for the presence of S. haematobium ova. Results: In Pap smears, S. haematobium ova were detected in 8/394 (2.0%). SCA was found in 107/394 (27.1%), seven of these had high-grade squamous intraepithelial lesion (HSIL). Schistosoma specific DNA was detected in 38/394 (9.6%) of vaginal lavages and in 91/394 (23.0%) of urines. Ova were found microscopically in 78/394 (19.7%) of urines. Conclusion: Schistosoma PCR on lavage was a better way to diagnose FGS compared to cytology. There was a significant association between S. haematobium ova in Pap smears and the other diagnostic methods. In low-resource Schistosoma-endemic areas, it is important that cytology screeners are aware of diagnostic challenges in the identification of schistosomiasis in addition to the cytological diagnosis of SCA. Importantly, in this study, three of eight urines were negative but showed Schistosoma ova in their Pap smear, and one of them was also negative for Schistosoma DNA in urine. In this study, SCA was not significantly associated with schistosomiasis. HSIL detected in this young population might need future consideration.
Chemical composition of essential oil from the seed Arils of Strelitzia nicolai Regel & Koern from South Africa
(Taylor and Francis, 2015-02-23) Chalannavar, Raju K.; Venugopala, Katharigatta Narayanaswamy; Baijnath, Himansu; Odhav, Bharti
The essential oil components of arils from seeds of Strelitzia nicolai were investigated by GC and GC-MS. The oil yields of dried arils obtained by hydrodistillation were 0.86 %. Twenty-five compounds representing 94.2 % of the S. nicolai aril oil were identified. The main chemical constituents belongs to alcohols (1.24 %), amides (3.14 %), amine (31.75 %), aromatic compounds (4.86 %), esters (0.65 %), ethers (28.18 %), hydrocarbons (5.13 %) and ketones (19.30 %).
The chemical composition of leaf essential oils of Psidium guajava L. (white and pink fruit forms) from South Africa
(Taylor and Francis, 2015-02-23) Chalannavar, Raju K.; Venugopala, Katharigatta Narayanaswamy; Baijnath, Himansu; Odhav, Bharti
The leaf oils of Psidium guajava (white fruit) and Psidium guajava (pink fruit) collected in KwaZulu-Natal province of South Africa has been examined by Gas chromatography-Mass spectrometry (GC-MS), and the apparent concentrations were determined by gas chromatography with a flame ionization detector. A total of twenty compounds of 88.9 % from white fruit and forty eight compounds representing 97.5 % from pink fruit of the oils were identified. P. guajava (white fruit) produced oil that was much richer in hydrocarbons (38.8 %), sesquiterpenes hydrocarbons (24.0 %), oxygenated sesquiterpenes (19.1 %) and alcohol (6.8 %). The major constituents of the essential oil were caryophyllene oxide (14.0 %), caryophyllene (13.9 %), 1H-cycloprop[e]azulene (11.6 %), adamantane (9.4 %), 3,7,11-trimethyl-1,6,10-dodecatrien-3-ol (6.8 %), α-cubebene (6.7 %), 1,2,3,4-tetrahydronaphthalene (3.9 %), β-humulene (3.5 %), 1,2,4a,5,6,8a-hexahydronaphthalene (3.2 %) and α-caryophyllene (3.0 %). The leaf oil of P. guajava (pink fruit) contained a mixture of hydrocarbons (30.5 %), sesquiterpene hydrocarbons (25.4 %), alcohol (24.4 %) and oxygenated sesquiterpenes (15.0 %). The major constituents of the essential oil were caryophyllene oxide (13.0 %), tetracyclo[6.3.2.0(2,5).0(1,8)]tridecan-9-ol (12.9 %), caryophyllene (9.5 %), 3,7,11-trimethyl-1,6,10-dodecatrien-3-ol (9.5 %), 1H-cycloprop[e]azulene (8.1 %), Z-3-hexadecen-7-yne (4.6 %) and eudesma-4(14),11-diene (4.1 %). High concentration of caryophyllene oxide and caryophyllene in both the oils suggests its usefulness as natural preservatives in the food industry. The terpenic and ester compounds could contribute to the unique flavor of P. guajava leaves.
Cheminformatics identification and validation of dipeptidyl peptidase-IV modulators from Shikimate pathway-derived phenolic acids towards interventive type-2 diabetes therapy
(MDPI AG, 2022-10) Balogun, Fatai Oladunni; Naidoo, Kaylene; Aribisala, Jamiu Olaseni; Pillay, Charlene; Sabiu, Saheed
Recently, dipeptidyl peptidase-IV (DPP-IV) has become an effective target in the management of type-2 diabetes mellitus (T2D). The study aimed to determine the efficacy of shikimate pathway-derived phenolic acids as potential DPP-IV modulators in the management of T2D. The study explored in silico (molecular docking and dynamics simulations) and in vitro (DPP-IV inhibitory and kinetics assays) approaches. Molecular docking findings revealed chlorogenic acid (CA) among the examined 22 phenolic acids with the highest negative binding energy (-9.0 kcal/mol) showing a greater affinity for DPP-IV relative to the standard, Diprotin A (-6.6 kcal/mol). The result was corroborated by MD simulation where it had a higher affinity (-27.58 kcal/mol) forming a more stable complex with DPP-IV than Diprotin A (-12.68 kcal/mol). These findings were consistent with in vitro investigation where it uncompetitively inhibited DPP-IV having a lower IC₅₀ (0.3 mg/mL) compared to Diprotin A (0.5 mg/mL). While CA showed promising results as a DPP-IV inhibitor, the findings from the study highlighted the significance of medicinal plants particularly shikimate-derived phenolic compounds as potential alternatives to synthetic drugs in the effective management of T2DM. Further studies, such as derivatisation for enhanced activity and in vivo evaluation are suggested to realize its full potential in T2D therapy.
Coumarin containing hybrids and their pharmacological activities
(Phytochemistry & Organic Synthesis Laboratory, 2021-08-09) Kasumbwe, Kabange; Saheed, Sabiu; Makhanya, Talent R.; Venugopala, Katharigatta Narayanaswamy; Mohanlall, Viresh
Coumarin moiety is of great interest to both chemists and biologists as it is present in a wide variety of naturally occurring bioactive compounds. Studies have lent scientific credence to the biological activities of several coumarin derivatives. The broad spectrum of biological activities linked with coumarin includes antibacterial, antimycobacterial, antioxidant, anticancer, antifungal, anti-inflammatory, anticoagulant and antiviral properties. The electron releasing and withdrawing substituent of coumarin affects the pharmacological properties of its resulting derivatives. Thus, identifying key structural features within the coumarin family is vital to the design and development of new analogues with enhanced pharmacological activity due to the variability in the structural complexity of coumarin. This article presents an up-to-date synopsis on the synthesis of coumarin derivatives and their pharmacological properties.
Current strategies in targeted anticancer drug delivery systems to brain
(Elsevier, 2021) Bania, Ratnali; Borah, Pobitra; Deka, Satyendra; Dahabiyeh, Lina A.; Singh, Vinayak; Al-Shar’i, Nizar A.; Nair, Anroop B.; Goyal, Manoj; Venugopala, Katharigatta N.; Tekade, Rakesh Kumar; Deb, Pran Kishore; Dua, Kamal; Mehta, Meenu; de Jesus Andreoli Pinto, Terezinha; Pont, Lisa; Williams, Kylie; Rathbone, Michael
Advanced Drug Delivery Systems in the Management of Cancer discusses recent developments in nanomedicine and nano-based drug delivery systems used in the treatment of cancers affecting the blood, lungs, brain, and kidneys. The research presented in this book includes international collaborations in the area of novel drug delivery for the treatment of cancer. Cancer therapy remains one of the greatest challenges in modern medicine, as successful treatment requires the elimination of malignant cells that are closely related to normal cells within the body. Advanced drug delivery systems are carriers for a wide range of pharmacotherapies used in many applications, including cancer treatment. The use of such carrier systems in cancer treatment is growing rapidly as they help overcome the limitations associated with conventional drug delivery systems. Some of the conventional limitations that these advanced drug delivery systems help overcome include nonspecific targeting, systemic toxicity, poor oral bioavailability, reduced efficacy, and low therapeutic index. This book begins with a brief introduction to cancer biology. This is followed by an overview of the current landscape in pharmacotherapy for the cancer management. The need for advanced drug delivery systems in oncology and cancer treatment is established, and the systems that can be used for several specific cancers are discussed. Several chapters of the book are devoted to discussing the latest technologies and advances in nanotechnology. These include practical solutions on how to design a more effective nanocarrier for the drugs used in cancer therapeutics. Each chapter is written with the goal of informing readers about the latest advancements in drug delivery system technologies while reinforcing understanding through various detailed tables, figures, and illustrations. Advanced Drug Delivery Systems in the Management of Cancer is a valuable resource for anyone working in the fields of cancer biology and drug delivery, whether in academia, research, or industry. The book will be especially useful for researchers in drug formulation and drug delivery as well as for biological and translational researchers working in the field of cancer.
Densities and excess molar volume for the ternary systems (1-Butyl-3-methylimidazolium methyl sulphate + Nitromethane + Methanol or Ethanol or 1-Propanol) at T = (303.15 and 313.15) K
(SA Epublications, 2013) Bahadur, Indra; Deenadayalu, Nirmala
The densities of the ternary systems containing the ionic liquid 1-butyl-3-methylimidazolium methyl sulphate ([BMIM]+[MeSO4]–) were determined. The ternary systems studied were ([BMIM]+[MeSO4]– + nitromethane + methanol or ethanol or 1-propanol) at the temperatures (303.15 and 313.15) K. The ternary excess molar volumes were calculated from the experimental densities at each temperature, being negative for all mole fractions of the ionic liquid. The minimum ternary excess molar volumes increase with an increase in temperature for the systems ([BMIM]+[MeSO4]– + nitromethane + methanol or ethanol), and decrease for the system ([BMIM]+ [MeSO4]–+ nitromethane + 1-propanol). The results are interpreted in terms of the alcohol chain length and the intermolecular interactions.