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Chemosphere ◽  
2022 ◽  
Vol 287 ◽  
pp. 132373
Author(s):  
Hessamaddin Sohrabi ◽  
Mir Reza Majidi ◽  
Karim Asadpour-Zeynali ◽  
Alireza Khataee ◽  
Ahad Mokhtarzadeh

2021 ◽  
Vol 10 (36) ◽  
pp. 263-264
Author(s):  
Peter Christian Endler ◽  
Christian Reich ◽  
Wolfgang Matzer ◽  
Thomas Reischl ◽  
Anna Maria Hartmann ◽  
...  

Control experiments were performed at different seasons of the year as a follow-up to pilot experiments [1] where a homeopathic high dilution of gibberellic acid had influenced growth in a wheat bio assay (7 days). Grains of winter wheat (Triticum aestivum, Capo variety) were observed under the influence of extremely diluted gibberellic acid (10-30) prepared by stepwise dilution and agitation according to a protocol derived from homeopathy (“G30x”). Analogously prepared water was used for control (“W30x”). Following up on 5 pilot experiments (4 in autumn 2007, 1 in spring 2008), 10 experiments were performed (5 in autumn 2008 or 2009 and 5 in winter 2009 or 2010) with a total of 9 experiments in autumn season (5 researchers, about 9,000 grains), and 6 in winter/spring (4 researchers, about 6,000 grains). Germination rates after 7 days were slightly higher for the autumn experiments (96.1%) than for the winter/spring experiments (94.8%) (p > 0,05), with a non significant trend of more seedlings having germinated in the verum group in the autumn experiments (p > 0,05). All of the 9 autumn experiments (i.e. pilot as well as repetition experiments) showed less stalk growth in the verum group (statistically significant with p < 0.01 in 4, with p < 0.05 in 3 cases, trend in 2 cases). Mean stalk lengths (mm) were 46.97 + 20.50 for the verum group and 50.66 + 19.77 for control (mean + S.D.) at grain level (N = 4,440 per group) and + 3.87 and + 3.38 (+ S.D.) respectively at dish level (217 cohorts of 20 or 25 grains per treatment group). In other words, verum stalk length (92.72%) was 7.28% smaller than control stalk length (100%). The effect size (D means : S.D.), calculated on the basis of dishes, was high (d = 1.02). In contrast, no reliable effect was found in experiments performed in winter/spring (less stalk growth in the verum group in one case, no difference in 2 cases, and more growth in 3 cases). Overall verum stalk length (103.64%) was slightly greater than control stalk length (100%). The effect size, however, was small (d = 0.45). The new data are in line with the 2007 findings, i.e. confirm that gibberellic acid 30x does influence stalk growth.


Author(s):  
Waltraud Scherer-Pongratz ◽  
Peter Christian Endler

Objective: Performing a study on a wheat growth bio assay with a homeopathic dilution of gibberellic acid at different seasons of the year. Methods: Grains of winter wheat (Triticum aestivum, Capo variety) were observed under the influence of extremely diluted gibberellic acid (10-30, 30x). Analogously prepared water was used for control. 15 experiments were performed, 9 in autumn season (5 researchers, 4,440 grains per group), and 6 in winter / spring (4 researchers, with 3,140 grains per group). Results: All 9 autumn experiments showed less stalk growth in the verum group (p > 0.01 in 4 cases, p > 0.05 in 3, trend in 2 cases). Mean stalk lengths (mm) were 46.97 + 20.50 for verum and 50.66 + 19.77 for control at grain level (N = 4,440 per group) and + 3.87 and + 3.38 respectively at dish level (217 cohorts of 20 or 25 grains per treatment group). Verum stalk length (92.72%) was 7.28% smaller than control stalk length (100%). In contrast, no reliable effect was found in experiments performed in winter / spring (less stalk growth in 1 case, no difference in 1, more growth in 3 cases). Overall verum stalk length (103.64%) was 3.64% slightly greater than control stalk length (100%). Data were found to be homogeneous within the control groups as well as within the verum groups. Conclusion: Results suggest that especially in the experiments performed in autumn, there was an influence of gibberellic acid 30x on wheat seedling development. The effect size is small when calculation is done on the basis of grains (d = 0.18) but high when done on the basis of dishes (d = 1.02). In contrast, no reliable effect was found in experiments performed in winter / spring. Further experiments should thus be performed in the autumn season.


2021 ◽  
Vol 10 (36) ◽  
pp. 196-197
Author(s):  
Gerhard Lingg ◽  
Peter Christian Endler

Experiments on amphibian metamorphosis can vary considerably in duration. The authors had set themselves the task of defining a generally applicable pooling method for metamorphosis experiments [1]. Normalization with respect to time was done on the assumption that differences in speed of metamorphosis attributable to treatment would override differences in duration between experiments. The problem of artificial differences in variability when comparing and pooling data from several experiments was approached by normalization with respect to time based on the development of both the test and the control animals. The range from 0% to 100% over which the fraction of four-legged animals progresses in the course of an experiment is divided into 10%-intervals and mapped onto a corresponding relative scale. Each measurement is then assigned to the point on the 10%-scale to which it is closest. In this way each reference point is assigned a value giving the number or percentage of four-legged animals at that point. These values are aggregated over all experiments within the test- and control-group. The results of experiments performed over the course of two decades (1990 - 2010) on highland Rana temporaria treated with a homeopathically prepared high dilution of thyroxine (“30x”) are presented in full detail based on this normalization method[1]. It was found that differences between treatment groups thus calculated were in line with those obtained with other pooling methods [2]. Thyroxine 30x does slow down metamorphosis in inert highland amphibians. This was observed by 5 researchers in 20 sub-experiments, and it seems to be the most reliable bio-assay found in amphibian research on homeopathy so far2. When experiments were performed with highland animals pretreated by hyperstimulation with molecular thyroxine, slowing down of metamorphosis was again observed (by 3 of 4 researchers) in most of 10 sub-experiments.


Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 969
Author(s):  
Francesca Capetti ◽  
Massimo Tacchini ◽  
Arianna Marengo ◽  
Cecilia Cagliero ◽  
Carlo Bicchi ◽  
...  

Excessive melanin production causes serious dermatological conditions as well as minor aesthetic problems (i.e., freckles and solar lentigo). The downregulation of tyrosinase is a widespread approach for the treatment of such disorders, and plant extracts have often proven to be valuable sources of tyrosinase inhibitors. Citral (a mixture of neral and geranial) is an important fragrance ingredient that has shown anti-tyrosinase potential. It is highly concentrated in the essential oils (EOs) of Cymbopogon schoenanthus (L.) Spreng., Litsea cubeba (Lour.) Pers., Melissa officinalis L., and Verbena officinalis L. However, only L. cubeba EO has been investigated for use as a potential skin-whitening agent. This work evaluates the in vitro tyrosinase inhibitory activity of these EOs and studies, using bio-assay oriented fractionation, whether their differing chemical compositions influence the overall EO inhibitory activities via possible synergistic, additive, and/or competitive interactions between EOs components. The inhibitory activity of C. schoenanthus EO and that of M. officinalis EOs, with negligible (+)-citronellal amounts, were in-line with their citral content. On the other hand, L. cubeba and V. officinalis EOs inhibited tyrosinase to considerably greater extents as they contained β-myrcene, which contributed to the overall EO activities. Similar observations were made for M. officinalis EO, which bears high (+)-citronellal content which increased citral activity.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 582
Author(s):  
Julius Sundermann ◽  
Steffen Sydow ◽  
Laura Burmeister ◽  
Andrea Hoffmann ◽  
Henning Menzel ◽  
...  

Chitosan nanogel-coated polycaprolactone (PCL) fiber mat-based implant prototypes with tailored release of bone morphogenic protein 2 (BMP-2) are a promising approach to achieve implant-mediated bone regeneration. In order to ensure reliable in vitro release results, the robustness of a commercially available ELISA for E. coli-derived BMP-2 and the parallel determination of BMP-2 recovery using a quantitative biological activity assay were investigated within a common release setup, with special reference to solubility and matrix effects. Without bovine serum albumin and Tween 20 as solubilizing additives to release media buffed at physiological pH, BMP‑2 recoveries after release were notably reduced. In contrast, the addition of chitosan to release samples caused an excessive recovery. A possible explanation for these effects is the reversible aggregation tendency of BMP-2, which might be influenced by an interaction with chitosan. The interfering effects highlighted in this study are of great importance for bio-assay-based BMP-2 quantification, especially in the context of pharmaceutical release experiments.


2021 ◽  
Vol 11 ◽  
Author(s):  
Le Nguyen Tuong Vi ◽  
Nguyen Ngoc Tuan ◽  
Quach Tong Hung ◽  
Pham Thi Nhat Trinh ◽  
Tong Thanh Danh ◽  
...  

Background: In recent years, the study of the structure and biological activity of medicinal plants has a particularly important to search for diabetes medicine. Ruellia tuberosa is used to treat various diseases such as diabetes by inhibiting the activity of α-glucosidase. Objective: In this study, experiment was designed to isolated isolate and identified identify α-glucosidase inhibitory extracts and compounds from Ruellia tuberosa L. through bio-assay guided isolation. Method: Dry powder of Ruellia tuberosa L. was extracted with 70% ethanol, then liquid-liquid partition with n-hexane, ethyl acetate and butanol, respectively. The extracts were evaluated with α-glucosidase inhibition. The potential extracts were isolated and identified compounds. The effects of these compounds on the α-glucosidase inhibitory were evaluated. Results: The a-glucosidase inhibitory activities showed that the n-hexane, ethyl acetate and the butanol extract had the α-glucosidase inhibition with an IC50 of 46.2 0.9, 6.6 2.9 and 8.9  μg/mL, respectively. From the n-hexane and ethyl acetate extracts, the structures of four compounds were elucidated by NMR spectroscopic method, including lupeol (1), syringaresinol (2), apigenin (3), verbascoside (4). The a-glucosidase inhibitory activities showed that all isolated compounds were more active than the positive control - acarbose with an IC50 of 37.5  0.4; 19.5  0.2; 20.1  0.3; 69.3  0.2 µg/mL, respectively. Conclusion: The ethyl acetate extract showed strong activity about 19 times more than positive control - acarbose. The compound syringaresinol (2) was the most powerful α-glucosidase inhibitor. Therefore, Ruellia tuberosa L. contains many compounds that can inhibit α-glucosidase activity.


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