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51.
Feijoa sellowiana leaves and fruits have been investigated as a source of diverse bioactive metabolites. Extract and eight metabolites isolated from F. sellowiana leaves were evaluated for their enzymatic inhibitory activity against α-glucosidase, amylase, tyrosinase, acetylcholinestrerase and butyrylcholinesterase both in vitro and in silico. Feijoa leaves’ extract showed strong antioxidant activity and variable levels of inhibitions against target enzymes with a strong anti-tyrosinase activity (115.85 mg Kojic acid equivalent/g). Additionally, α-tocopherol emerged as a potent inhibitor of AChE and BChE (5.40 & 10.38 mmol galantamine equivalent/g, respectively). Which was further investigated through molecular docking and found to develop key enzymatic interactions in AChE and BChE active sites. Also, primetin showed good anti BChE (11.70 mmol galantamine equivalent/g) and anti-tyrosinase inhibition (90.06 mmol Kojic acid equivalent/g) which was also investigated by molecular docking studies.

Highlights

  • Isolation of eight bioactive constituents from Feijoa sellowiana leaves.
  • In vitro assays using different enzymatic drug targets were investigated.
  • In silico study was performed to define compound interactions with target proteins.
  • Feijoa leaf is an excellent source of anti-AChE and antityrosinase bioactives.
  相似文献   
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This study investigated the fate of enhanced biological phosphorus removal (EBPR) and changes in microbial speciation in a sequencing batch reactor (SBR) fed with aspartate and glutamate. It involved SBR operation for 288 days, batch tests for observation of metabolic functions together with microscopic and phylogenetic analyses. Polyphosphate accumulating organisms (PAOs) were observed in abundance with complete removal of phosphorus. Fluorescence in situ hybridization (FISH) combined with 4′,6-dia-midino-2-phenylindole (DAPI) staining confirmed the accumulation of polyphosphate by Rhodocyclus-related and Actinobacterial PAOs. Aspartate seemed to favor the competitive growth of Rhodocyclus-related PAOs since EBPR population used the common biochemical pathways followed by Rhodocyclus-related PAOs in the aspartate fed batch tests. In the glutamate fed batch reactors, however, Actinobacterial PAOs appeared to be competitively selected which explains the lower levels of PHA generation. Even though operational conditions did not change, effective EBPR could not be maintained during the latter part of the study.  相似文献   
54.
The aim of the present study was to quantify selected phenolic compounds, determine antioxidant activity and enzyme inhibitory effects of the aerial parts of Alkanna trichophylla Hub.-Mor. (A. trichophylla) and Convolvulus galaticus Rost.ex Choisy (C. galaticus) extracts prepared by homogenizer-assisted extraction (HAE), maceration (MAC) and infusion techniques. This is the first time such study has been designed to validate the phytochemical composition and bioactivity of these plants. Multivariate analysis was conducted on collected data. Rutin and caffeoylquinic acid derivatives were the most significant compounds in A. trichophylla and C. galaticus, respectively. The highest antioxidant activity of A. trichophylla was mostly exhibited by HAE/methanolic extracts as determined by DPPH, ABTS, FRAP (51.39, 112.70 and 145.73 mg TE/g, respectively) and phosphomolybdenum (2.05 mmol TE/g) assays. However, significant antioxidant activities varied within the extracts of C. galaticus. HAE/methanolic extract of A. trichophylla significantly depressed AChE (2.70 mg GALAE/g), BChE (5.53 mg GALAE/g) and tyrosinase (26.34 mg KAE/g) activities and that of C. galaticus inhibited AChE (2.04 mg GALAE/g), tyrosinase (31.25 mg KAE/g) and α-amylase (0.53 mmol ACAE/g) activities significantly. We concluded that HAE was the most efficient extraction technique as high yield of compounds and promising bioactivities were recorded from extracts prepared. Multivariate analysis showed that types of solvents influenced recovery of compounds and biological activities. This research study can be used as one methodological starting point for further investigation on these plants as all results are clearly promising and open the door to further research challenges such as cytotoxicity evaluation, molecular docking analysis, and more screening of pharmacological actions.  相似文献   
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The leaf anatomy of 22 Alpinia species from the Malay Peninsular was investigated. Results show that a combination of characters such as outlines of midribs, petioles, leaf margins and their relative sizes in transverse sections as well as the presence of hypodermal fibres in the lamina, midribs and petioles can be used in the identification of species. All four species of subsection Allughas possess similar characters such as the presence of abaxial and adaxial fibres in the midrib and petioles and the absence of hypodermis in the lamina while the reverse is true for all species of subsection Catimbium. Alpinia conchigera and A. galanga appear to be closely related while A. oxymitra is distinct from all the species studied.  相似文献   
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Rhoifolin (apigenin-7-O-β-neohesperidoside) belongs to the class of flavonoids and was reported to exhibit anti-inflammatory, cytotoxic, antidiabetic, hepatoprotective, and cardioprotective activities. The current study presents the in-vitro evaluation of the antioxidative effects of rhoifolin by many assays, namely DPPH, CUPRAC, ABTS, phosphomolybdenum, and FRAP. Enzyme inhibitory potential was also evaluated for acetylcholinesterase (AChE), butyrylcholinesterase (BChE), tyrosinase, amylase, and glucosidase enzymes. While results revealed weak antioxidant activities for rhoifolin, the compound demonstrated some promising enzyme inhibitory effects against BChE (4.03 mg GALAE/g) and tyrosinase (7.44 mg KAE/g) but was not active on AChE. Regarding anti-diabetic enzymes, the compound was active on amylase but did not show any inhibition effect on glucosidase. In-silico molecular docking study was performed for rhoifolin on the active site of NADPH oxidase, BChE, and amylase enzymes to verify the observed enzyme inhibitory effect. Good binding affinities were observed for rhoifolin on all the docked enzymes, revealing numerous hydrogen bonds, carbon-hydrogen, van der Waals interactions. This is the first study to evaluate the enzyme inhibition potential of rhoifolin. We concluded that the increase in the degree of glycosylation might decrease the antioxidant abilities of flavonoids and that rhoifolin had moderate enzyme inhibition abilities to be investigated in future studies.  相似文献   
58.
Seasonal landings and survey data from the Turkish shrimp beam trawl fishery were analyzed. A total of 32 valid hauls from twelve boats were analyzed 17 in autumn, 12 in spring and three in winter. The estimated by-catch to shrimp ratios exhibited a seasonal pattern, with autumn having the highest ratio. In total, the by-catch consisted of 57 species belonging to six groups of marine fauna, including Osteichthyes (25 species), Chondrichthyes (three species), Crustacea (six species), Mollusca (11 species), Cephalopoda (five species) and Echinodermata (seven species). The Osteichthyes form the most abundant (52.6%) by-catch group, followed by Crustacea > Chondrichthyes > Echinodermata > Cephalopoda > and Mollusca. Whiting, Merlangius merlangus euxinus and hake, Merluccius merluccius dominated in the commercially utilized part of the by-catch, while swimming crab, Leocarcinus depurator and gobies, Gobius bucchichi, G. niger dominated the discarded part of catches. The mean catch per unit effort (CPUE) obtained from all hauls was 5.91 ± 0.62 kg h−1. There were no statistically significant differences among mean CPUE values per season (P   >   0.05).  相似文献   
59.
The traditional view of skeletal homeostasis as a primarily endocrine activity has been expanded in recent years following the identification of direct neural pathways controlling bone homeostasis via central relays. Powerful control over both anabolic and catabolic activities have been isolated to neurons of the hypothalamus, enabling large changes in bone mass to be achieved by minute changes in the levels of these central neural signals. Initiated by studies of leptin and expanding rapidly, the breadth and complexity of this regulatory axis to bone is sure to increase. Critically though, the translation of these findings into therapeutic interventions is likely to present a greater challenge. However, the contribution to our understanding that these initial studies are making indicates an exciting potential to help to alleviate the growing challenge presented by musculoskeletal disease.  相似文献   
60.
The aim of the present work is to develop nanoemulsions (NEs), nanosized emulsions, manufactured for improving the delivery of active pharmaceutical ingredients. In particular, nanoemulsions composed of Neem seed oil, contain rich bioactive components, and Tween 20 as nonionic surfactant were prepared. A mean droplet size ranging from 10 to 100?nm was obtained by modulating the oil/surfactant ratio. Physicochemical characterisation was carried out evaluating size, ζ-potential, microviscosity, polarity and turbidity of the external shell and morphology, along with stability in simulated cerebrospinal fluid (CSF), activity of Neem oil alone and in NEs, HEp-2 cell interaction and cytotoxicity studies. This study confirms the formation of NEs by Tween 20 and Neem oil at different weight ratios with small and homogenous dimensions. The antioxidant activity of Neem oil alone and in NEs was comparable, whereas its cytotoxicity was strongly reduced when loaded in NEs after interaction with HEp-2 cells.  相似文献   
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