Prolongevity effects of an oregano and cranberry extract are diet dependent in the Mexican fruit fly (Anastrepha ludens)

Abstract

Botanicals have numerous health benefits. Here, we used the Mexican fruit fly to screen 14 compounds and botanicals for their prolongevity effects and found an oregano and cranberry mixture (OC) improved survival. We then evaluated prolongevity effects of OC within the context of diet composition. Individual flies were fed 0%, 1%, or 2% OC in one of the three diets containing sugar and yeast extract (SY) at a ratio of 3:1, 9:1, or 24:1. We found that prolongevity effects of OC depended upon dose, gender, and diet composition. The greatest increase in longevity was observed in females fed the SY24:1 diet with 2% OC compared to the non-supplemented diet. OC did not reduce egg laying and, hence, did not compromise fecundity under any dietary condition tested here. This study reveals the prolongevity effects of OC and supports the emerging view that benefits of botanicals on aging depend on diet composition and gender.

Figure 1.

Life-span curves of mexflies fed the standard 9:1 sugar and yeast extract diet in population cages. Concentrations of oregano and cranberry (OC) mixture in the food as percentages and the life expectancy of flies in days from each treatment are depicted in graphs. Each life-span curve was generated by pooling data from two replicates performed with two population cages for each treatment and four replicates for the control.

Figure 2.

Life-span curves of female and male mexflies individually fed the standard 9:1 sugar and yeast extract diet supplemented with 0%, 1%, or 2% oregano and cranberry (OC) mixture. Concentrations of OC in the food as percentages and mean life span of flies in days from each treatment are depicted in graphs.

Figure 3.

Life-span curves of female and male mexflies individually fed a 3:1 sugar and yeast extract (SY) diet (A and B) or a 24:1 diet (C and D) supplemented with 0%, 1%, and 2% oregano and cranberry (OC) mixture. SY ratios, concentrations of OC in the food as percentages, and mean life span of flies in days from each treatment are depicted in graphs.

Figure 4.

Life-span response surfaces showing the effects of diet composition and oregano and cranberry (OC) mixture concentrations in the diet on mean (A and B) and maximum (C and D) life span of females and males. x-axis represents OC concentration and y-axis represents the ratio of dietary yeast in the food. The life span in days is color coded and superimposed on the graphs.

Figure 5.

The effect of dietary composition and oregano and cranberry (OC) mixture on fecundity. (A) Lifetime egg laying per fertile female in relation to diet and OC concentration. (B) Life event history depicting the relationship among life span, egg laying, and OC supplementation. The sugar and yeast ratio and OC concentration are shown in each panel. x-axis represents life span in days and y-axis represents the identity of individual flies ranked according to longevity. The length of a green bar reflects the life span of one fly. The number of daily egg laying is color coded and superimposed on the life-span data.