You have discovered the problem with using non-composted bamboo leaves, rutin and orientin are compounds found in bamboo leaves.
These two compounds have synergistic inhibition effects on many nutrient compounds found in soils, the effect is that these nutrients are no longer available for uptake by any plants.
The result of this nutrient binding is allopathic to plants other than bamboo, which renders the soil uninhabitable by other species.
To use Bamboo leaves as mulch in gardens, you first need to hot
compost them so the rutin and orientin are neutralized.
Loquat leaves (Eriobotyra japonica Lindl) do not contain any disruptive compounds but their health benefits are such that they are better put to use in herbal teas.
The extracts of Loquat leaves have also been shown to help cure and even prevent breast cancers. They can also help in treatment of liver disorders.
To use Loquat leaves as mulch I would simply distribute them over the area I was wanting to mulch.