The Trend of Bacterial Nanocellulose Research Published in the Science Citation Index Expanded From 2005 to 2020: A Bibliometric Analysis.

To gain insight into the trend of bacterial nanocellulose research, a bibliometric analysis was performed using the Science Citation Index Expanded database from 2005 to 2020. The study concentrated on the publication's performance in terms of annual outputs and citations, mainstream journals, categories of the Web of Sciences, leading countries, prominent institutions, and trends in research. Current research priorities and future trends were analyzed after summarizing the most commonly used keywords extracted from words in the paper title analysis, authors' keyword analysis, and KeyWords Plus. The findings revealed that the annual output in the form of scholarly articles on bacterial nanocellulose research steadily increased during the first quartile of the study period, followed by a very rapid increase in the last five-years of the study. Increasing mechanical strength would remain the main future focus of bacterial nanocellulose research to create its scope in different field of applications.

Transformation of jervine by Cunninghamella elegans ATCC 9245.

Preparative-scale fermentation of the known C-nor-D-homosteroidal jerveratrum alkaloid jervine with Cunninghamella elegans (ATCC 9245) has resulted in the isolation of (-)-jervinone as the major metabolite. In addition, C. elegans ATCC 9245 was able to epimerize C-3 of jervine, producing 3-epi-jervine. This epimerization reaction was similar to that reported for tomatidine, the known spirosolane-type Solanum alkaloid. The structure elucidation of both metabolites was based primarily on 1D- and 2D-NMR analyses.

Cytotoxic triterpenes from Cleome africana.

Eighteen dammarane-type triterpenes were obtained from the whole plant of Cleome africana by means of cytotoxic bioassay-directed fractionation. Twelve of them were novel compounds whose structures were elucidated by various spectroscopic methods.

(+)-Sparteine N-16-oxide, a lupin alkaloid from Lygos raetam var. sarcocarpa.

A new lupin alkaloid, (+)-sparteine N-16-oxide was isolated from Lygos raetam var. sarcocarpa, together with five known alkaloids: (+)-aphylline, (+)-17 oxosparteine, (-)-5,6-dehydrolupanine, (-)-N-formyl cytisine and (+)-ammodenderine. The structure of the new alkaloid including absolute configuration was determined by spectroscopic methods and chemical transformation.

Comparative chemical and biological studies of the alkaloidal content of Lygos species and varieties growing in Egypt.

Quinolizidine and dipiperidyl alkaloids profiles have been determined for various plant organs of Lygos raetam Forssk. L. raetam var. sarcocarpa and L. raetam var. bovei, using TLC, GC, GC-MS and HPLC techniques. Sixteen quinolizidine and dipiperidyl alkaloids were identified including baptofoline alkaloid which have not previously been reported in the genus Lygos. Biological evaluulation including hypoglycemic effect, anti-inflammatory activity, and some pharmacological studies of the different extracts as well as some of the isolated alkaloids were also performed. N-methylcytisine was proved to have a significant hypoglycemic effect on the induced diabetic mice and anti-inflammatory effect against the induced odema as well as a sedation effect on locomotor activity enhanced by methamphetamine.

Pregnane glycosides from Caralluma retrospiciens.

Two pregnane ester glycosides were isolated and identified from the alcohol extract of the aerial parts of Caralluma retrospiciens. Their structures were established as 12 beta-benzoyloxy-20-isovaleroyloxy-8 beta,14 beta-dihydroxypregnane-3-O -[beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl -(1-->4)-beta-D-(3-O-methyl-6-deoxy)-galactopyranoside] (caretroside A) and the bioside 12 beta-benzoyloxy-8 beta,14 beta-dihydroxypregn-20-one-3-O-[beta -D-oleandropyranosyl-(1-->4)-beta-D-cymaropyranoside]. They were characterized through physical and chemical methods in addition to standard spectroscopic techniques especially 2D NMR (COSY, HMQC and HMBC). This is the first report of the isolation of these compounds from a natural source.

Anthraquinones from the polar fractions of Galium sinaicum.

The new anthraquinones, 6,7-dimethoxy xanthopurpurin, 6-hydroxy-7-methoxy rubiadin, 5-hydroxy-6-hydroxymethyl anthragallol 1, 3-dimethyl ether, 7-carboxy anthragallol 1,3-dimethyl ether, anthragallol 1-methyl ether 3-O-beta-D-glucopyranoside, anthragallol 1-methyl ether 3-O-rutinoside, anthragallol 3-O-rutinoside and alizarin 1-methyl ether 2-O-primeveroside were isolated from the CH2Cl2 and n-BuOH extracts of Galium sinaicum roots and their structures were established by various spectroscopic techniques. In addition, two known anthraquinones were also isolated and fully characterized.

Flavonol glycosides from Nitraria retusa.

The new flavonol trioside, isorhamnetin 3-O-4Rham-galactosylrobinobioside and five known flavonol glycosides, isorhamnetin 3-robinobioside, isorhamnetin 3-rutinoside, isorhamnetin 3-galactoside, isorhamnetin 3-glucoside and free isorhamnetin were isolated from the leaves and young stems of Nitraria retusa and characterized by UV and NMR spectroscopy. Isorhamnetin 3-xylosylrobinobioside was also tentatively identified.

Time course and inhibition of stavaroside K, veratramine and cevine-induced hemolysis by other pregnane glycosides and Veratrum alkaloids.

Stavaroside K, veratramine and cevine induce hemolysis, whereas 7 other pregnane stavarosides and 8 Veratrum alkaloids are not hemolytic. On the other hand, erythrocytes pretreated or incubated with low concentrations of stavarosides D-F or with the 8 other Veratrum alkaloids were resistant to hemolysis induced by authentic saponin, stavaroside K, cevine or veratramine. Veratridine, zygadenine and angeloylzygadenine (the known Na-Channel-Gate toxins) revealed the most potent reduction of hemolytic activity.

Pregnane glycosides from Stapelia variegata.

Eleven new pregnane ester glycosides have been isolated from the aerial parts of Stapelia variegata. Eight of the recognized compounds were established to possess the same trioside moiety, viz. 3-O-[3-O-methyl-6-deoxy-beta-D-allopyranosyl-(1-4)-beta-D- cymaropyranosyl-(1-4)-beta-D-cymaropyranoside]. These compounds were identified as: stavaroside A: 12-O-beta-angeloyl-20-O-benzoyl sarcostin; stavaroside B: 12-O-beta-angeloyl-20-O-tigloyl sarcostin; stavaroside C: 11 alpha-acetoxy 2 beta-benzoxy-3 beta,8 beta, 14 beta-trihydroxy-pregn-5-ene-20-one; stavaroside D: 11 alpha-acetoxy- 12 beta-tigloxy-3 beta,8 beta,14 beta-trihydroxy-pregn-5-ene-20-one; stavaroside E: 12-O-beta-benzoyl sarcostin; stavaroside F: 11 alpha-acetoxy-12 beta-acetoxy-3 beta,8 beta,14 beta-trihydroxy-pregn-5- ene-20-one; stavaroside G: 12-O-beta,20-O-diacetyl sarcostin and stavaroside H: 3 beta, 8 beta, 11 alpha, 12 beta, 14 beta-pentahydroxy-pregn-5- ene-20-one. The other three compounds were shown to possess the same tetraside sugar moiety, viz. 3-O-[beta-D-glucopyranosyl- (1-4)-3-O-methyl-6-deoxy-beta-D-allopyranosyl-(1-4)-beta-D-cymaropyra nosyl- (1-4)-beta-D-cymaropyranoside]. These compounds were identified as: stavaroside I: 1 alpha, 12 beta-angeloxy and benzoxy-3 beta,8 beta,14 beta-trihydroxy- pregn-5-ene-20-one; stavaroside J: 11 alpha-acetoxy-12 beta-benzoxy-3 beta, 8 beta,14 beta-trihydroxy-pregn-5-ene-20-one and stavaroside K: 11 alpha-acetoxy-12 beta-tigloxy-3 beta,8 beta,14 beta-trihydroxy-pregn-5-ene- 20-one. The structural elucidation of the isolated compounds was aided significantly on the basis of the chemical and spectral evidence. The decisive assignments of the ester positions were based on the Inverse Detected-Heteronuclear Multiple Bond Connectivity (HMBC) experiments.