The aim of the present study was to investigate the potential role of an ethanolic extract of the entire plant of Cynodon dactylon in lowering the plasma lipid parameters in rats fed a high cholesterol diet. Wistar albino rats were randomly divided into four groups of six and for 45 days were administered either: 0.5 ml water (negative controls); 30 mg cholesterol (hypercholesterolemic animals); C dactylon extract at 400 mg/kg body weight (positive control); or the same doses of both cholesterol and the extract (test animals). The effects of C dactylon on the lipid profile were assessed by measuring the plasma concentrations of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), and very low-density lipoprotein cholesterol (VLDL-c). Administration of cholesterol showed significant elevation (p < 0.001) of TC, LDL-c, VLDL-c, and TG concentrations, and of the TC:HDL-c ratio (p < 0.05). Concurrent administration of C dactylon extract caused a significant decrease (p < 0.001) in the concentrations of serum TC, LDL, HDL, VLDL TGs when compared with cholesterol fed control rats.

Biomass from various sources such as cow dung is a significant source of renewable energy (as biogas) in many regions globally, especially in India, Africa, Brazil, and China. However, biogas production from biomass such as cattle dung is a slow, inefficient biochemical process, and the specific biogas produced per kg of biomass is relatively small. The improvement of specific biogas production efficiency using various dilution ratios (and, hence, total solids [TS]) is investigated in this work. A wide range of feed dilution (FD) ratios of cow dung: water (CD: W) was tested in batch biogas digesters with total solids ranging from 1% to 12.5% and FD ratio ranging from 2:1 to 1:20. To further verify the results from the above batch experiments, semi-batch experiments representative of field-scale biodigesters were conducted. Semi-batch reactors have a steady-state process, unlike batch reactors, which have an unsteady state process. Our results suggested that specific biogas production (mL/g VS) increased continuously when the total solids decreased from 12.5% to 1% (or when dilution increased). Our experiments also indicate that the commonly used 1:1 feed dilution ratio (TS ~ 10% for cow dung) does not produce the maximum specific biogas production. The possible reason for this could be that anaerobic digestion at higher total solids is rate limited due to substrate inhibition, mass transfer limitations, and viscous mixing problems that arise at higher total solids concentration. Hence, a higher feed dilution ratio between 1:2 and 1:4 (TS between 4 and 6.7%) is recommended for a more efficient biomass utilization of cowdung. Empirical relationships were also developed for variation of specific biogas yield with the total solids content of the cow dung slurry. Graphic abstract

In table 8, Sl. No. 7, the value of "Dilution ratio" should be "1:1.5-1:2" and not "1.5-1:2" as in the original publication of the article.Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.