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In order to investigate the anti-aging effects of Lycium ruthenicum Murr. granules (HGQ) and potential underlying mechanism of actions, Caenorhabditis elegans was exploited as model organisms. The anti-aging capacity of HGQ was determined by lifespan and lipofuscin fluorescence assays in wild-type C. elegans N2. Calorie restriction pathway was detected by pharyngeal pumping rate assay and lifespan examination in sir-2.1 mutant nematodes. The antioxidant activity of HGQ was investigated by determining reactive oxygen species (ROS) level, paraquat-stress survival rate, malondialdehyde (MDA) content as well as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities. We observed that HGQ exerted little effect on the growth of wild-type N2 nematodes at concentration < 0.6 mg/ml, and 0.05 mg/ml of the HGQ significantly prolonged the lifespan and reduced the lipofuscin level in N2 nematodes. However, the HGQ failed to influence the pharyngeal pumping rate in N2 nematodes or to affect the lifespan of sir-2.1 mutant nematode VC199, indicating the anti-aging effect of HGQ is independent of calorie restriction pathway. Further experiments showed that the HGQ decreased ROS and MDA contents and increased the survival rate and SOD (not CAT or GPx) activities in paraquat-stressed N2 nematodes. Our results suggest that HGQ can effectively delay the senescence of C. elegans, and this effect may be related with its significant antioxidant activity. [ABSTRACT FROM AUTHOR]

The current work presents energy efficient hot air drying by controlling the relative humidity (RH) including step-down and continuous dehumidification of RH as to specify material based on Weibull and Bi-Di models. The drying characteristics of yam slices of different thickness (6, 1 2 ,18 mm) and longan were investigated using two RH control strategies. Results showed th a t continuous decrease of RH was energy efficient for longan, while the stepdown strategy was more energy efficient for 12 or 18 mm thick yam slices drying. In terms of drying kinetics, the step-down control strategy of RH is more energy efficient for those materials whose drying rate as well as sample's temperature curves display three distinct stages and sample thickness is relative large. In terms of β and Bi values in Weibull and Bi-Di models respectively, it is observed th a t the step-down control strategy of RH drying method is more efficient when the β value exceeds 1 and the Bi value was more than 0.1. The current investigation provided an assessment method for the convective hot air drying method by controlling RH to improve drying efficient and save energy consumption. [ABSTRACT FROM AUTHOR]